neuromuscular ultrasound for the evaluation of … · could detect changes in peripheral nerves and...

NEUROMUSCULAR ULTRASOUND FOR THE EVALUATION OF

AMYOTROPHIC LATERAL SCLEROSIS

By

MICHAEL S. CARTWRIGHT, M.D.

A Thesis Submitted to the Graduate Faculty of

WAKE FOREST UNIVERSITY GRADUATE SCHOOL OF ARTS AND SCIENCES

in Partial Fulfillment of the Requirements for the Degree of

MASTER OF SCIENCE

in the Clinical and Population Translational Science Program

May 21st, 2012

Winston-Salem, North Carolina

Approved by:

Francis O. Walker, M.D., Advisor

Examining Committee:

Paul J. Laurienti, M.D., Ph.D., Committee Chair

Carol E. Milligan, Ph.D.

Gregory W. Evans, M.A.

ii

TABLE OF CONTENTS

Page

LIST OF ABBREVIATIONS…………………………………………………….. iii

LIST OF TABLES AND FIGURES……………….……………………………... iv

NEUROMUSCULAR ULTRASOUND DEFINITIONS………………………… v

ABSTRACT……………………..………………………………………………..... vi

Chapters

I. INTRODUCTION……………………………………………………... 1

II. PERIPHERAL NERVE AND MUSCLE ULTRASOUND IN AMYOTROPHIC LATERAL SCLEROSIS………………………..

Published in Muscle & Nerve, September 2011

22

III. DISCUSSION……………………………………………………….…. 40

IV. CURRICULUM VITAE………………………………………………... 52

iii

LIST OF ABBREVIATIONS

ALS: amyotrophic lateral sclerosis

ALSFRS-R: revised ALS functional rating scale

EI: echo intensity

EMG: electromyography

FVC: forced vital capacity

MIP: maximal inspiratory pressure

MND: motor neuron disease

MUNE: motor unit number estimation

SMA: spinal muscular atrophy

SOD1: superoxide dismutase 1

TDP-43: TAR DNA-binding protein 43

iv

LIST OF TABLES AND FIGURE

TABLES Page 1.1

Current and Potential ALS Biomarkers……………………………

6

1.2 Neuromuscular Ultrasound Findings in Motor Neuron Disease.......

8

2.1 Participant Demographics………………………………………….. 31 2.2 ALS Participant Characteristics……………………………………. 31 2.3 Ultrasonographic Comparisons

Between ALS Patients and Controls……………………..…………

32 2.4 Correlation Between Ultrasonographic

Parameters and Other Variables…………………………………….

33 3.1 Neuromuscular Ultrasound Studies in ALS……………………….. 41 FIGURES 1.1

ALS Diagnostic Criteria……………………………………………..

4

2.1

Ultrasonography of the Median Nerve.……………………………..

28

2.2 Ultrasonography of the Sural Nerve……………………………….. 29 2.3 Ultrasonography of the Biceps Brachii

and Brachialis Muscle Complex……………….……………………

30 3.1 Improved Diagnostic Accuracy of ALS with EMG

and Ultrasound Detection of Fasciculations…………………………

44 3.2 Prospective Study Design for Complete Assessment

of ALS using Neuromuscular Ultrasound………………………….

48

v

NEUROMUSCULAR ULTRASOUND DEFINTIONS

Anechoic: An absence of returning echoes, resulting in an image that is black.

Echogenicity: The degree to which a structure reflects echoes back toward the transducer.

Increased echogenicity results in brighter images.

Echointensity: A quantitative assessment of echogenicity or brightness, typically

presented as a single mean value obtained using gray-scale analysis of a region of

interest.

Echotexture: The perceived texture of the image created after processing of the returning

echoes recorded by the transducer.

Gray-scale analysis: A quantitative technique used to assess black and white pictures,

such as ultrasound images, in which each pixel is assigned a value from 0 (black) to 255

(white) based on the shade of the gray in the pixel.

Hyperechoic: Increased echo signal, which results in a brighter image.

Hypoechoic: Decreased echo signal, which results in a darker image.

vi

ABSTRACT

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that causes

progressive loss of motor neurons, which results in weakness, respiratory compromise,

and typically death within 5 years of disease onset. The diagnosis is often delayed up to a

year from the time of onset because it is a clinical diagnosis and there are few tests

available to assist in the diagnostic evaluation. Neuromuscular ultrasound is an emerging

tool for the diagnosis of a variety of conditions, but it has not been studied extensively in

individuals with ALS. This study was designed to determine if neuromuscular ultrasound

could detect changes in peripheral nerves and muscles of individuals with ALS, which

could then be used to assist in diagnosis. Several neuromuscular ultrasound parameters

were compared between 20 individuals with ALS and 20 age and gender matched

controls. The cross-sectional area of the median nerve in the mid-arm was smaller in the

ALS group than controls (10.5 mm2 vs. 12.7 mm2, p = 0.0023), and the ALS group also

had a thinner biceps/brachialis muscle complex than controls (2.1 cm vs. 2.9 cm, p =

0.0007). These findings show that neuromuscular ultrasound can detect nerve and

muscle atrophy in ALS, so it should be further explored prospectively as a diagnostic tool

and possible disease biomarker.

1

CHAPTER I

INTRODUCTION

Amyotrophic lateral sclerosis (ALS), which is also known as Lou Gehrig’s disease in

the United States and Charcot’s or motor neuron disease (MND) in Europe, is a condition

in which motor neurons in the brain and spinal cord progressively die, which results in

limb weakness, dysarthria, dysphagia, dyspnea, and eventually respiratory compromise

and death.1 Onset can occur at any age after the second decade of life, but prevalence

escalates with increasing age and the peak age of onset is about 74 years old.2 The

incidence in the United States and Europe ranges between 1.5 and 2.7 cases per 100,000

per year, 2, 3 and the incidence may be lower amongst African, Asian, and Hispanic

ethnicities compared to whites.4 It occurs more often in men than women, and other

identified factors that slightly increase the risk of developing ALS include cigarette

smoking, United States military service, manual labor, athleticism, and trauma.2, 5-9 The

clinical presentation is variable, with asymmetric limb-onset weakness occurring in about

80% of cases, bulbar onset in nearly 20%, and diaphragmatic onset in fewer than 1%.10

Because both upper motor neurons (in the brain and spinal cord) and lower motor

neurons (starting in the spinal cord and extending outward) are lost, the pattern of clinical

manifestations is relatively unique and often involves progressive spasticity in addition to

atrophy and weakness.1 There is no cure for ALS, and the glutamate inhibitor riluzole,

which results in an increased life expectancy of just a few months, is the only approved

medical treatment.11, 12 Supportive care and interventions such as percutaneous

2

endoscopic gastrostomy feeding tubes and non-invasive ventilation have resulted in mild

increases in life expectancy for those with ALS, but the mean time of death is still 3-4

years from disease onset.13, 14

The etiology of ALS remains unknown. Approximately 90% of cases are sporadic

and 10% are familial, with the majority of inherited cases following an autosomal

dominant pattern. Until recently, the most commonly identified form of familial ALS

was caused by mutations in the superoxide dismutase 1 (SOD1) gene.15 While SOD1

mutations remain a cause in about 25% of familial ALS cases, very recent data indicate

that a hexanucleotide repeat expansion on chromosome 9p21 causes 46.0% of familial

ALS in a Finnish population. In addition, this gene is also linked to 21.1% of sporadic

ALS in the same population.16 While the complete pathophysiology of ALS remains

unknown, these recent genetic discoveries indicate that a large portion of ALS cases are

characterized by TAR DNA-binding protein (TDP-43) positive inclusions throughout the

nervous system.17 It has also been shown that mutations in the gene encoding the protein

ubiqulin 2 result in defects in the protein degradation pathway, which causes abnormal

protein aggregation and perhaps explains a common mechanism for familial and sporadic

ALS.18 Putting these recent genetic discoveries together has led to the intriguing theory

that perhaps ALS results from the accumulation of toxic RNA, which interferes with

normal cellular metabolism.16 Other implicated pathophysiologic mechanisms include

glutamate excitotoxicity, glial cell mediated processes, mitochondrial dysfunction,

growth factor deficiencies, and others.19

3

Diagnosing ALS

Despite advances in understanding the pathophysiology of ALS, there remains no

biochemical assay for the disease and establishing the diagnosis still requires a detailed

history and physical examination. For clinical and research purposes, diagnostic criteria

have been established through expert consensus, with the most commonly used criteria

being the revised El-Escorial clinical criteria and the Awaji electrodiagnostic criteria

(Figure 1.1).20, 21 These criteria are rooted in the basic premise that ALS causes death of

upper and lower motor neurons, which spreads to contiguous spinal segments. This

results in lower motor neuron findings of weakness, atrophy, fasciculations, and

denervation potentials seen with electromyography (EMG), and upper motor neuron

findings of spasticity, brisk reflexes, and the presence of normally absent pathologic

reflexes. Exclusion of other conditions that mimic ALS is also an important aspect of the

diagnostic process, and electrodiagnostic techniques (nerve conduction studies and EMG)

help confirm denervation and reinnervation and exclude sensory nerve involvement and

demyelination, which are uncommon in ALS.22 Taking all this information together, the

diagnosis of ALS is usually clear to clinicians experienced with the disease, but it can be

quite confusing to primary care physicians, non-neurologist specialists, and even

neurologists not accustomed to seeing individuals with ALS.23 This results in a mean

delay in diagnosis between 9 and 16 months, which can limit treatment options, decrease

enrollment in clinical trials, increase patient and family distress and anxiety, and perhaps

even close a window of time when motor neuron function is impaired but not irreversibly

damaged, as has been suggested by animal and human research.24-26

4

Figure 1.1. The revised El-Escorial and Awaji criteria are shown above. The Awaji criteria consider fasciculations to be evidence of lower motor neuron involvement and gives electrodiagnostic evidence of lower motor neuron dysfunction the same weight as clinical evidence.27 (LMN, lower motor neuron; UMN, upper motor neuron).

5

Development of other diagnostic tools is needed in ALS to help clinicians and

researchers diagnose the condition earlier and more accurately.25 Even clinicians with

extensive ALS experience encounter patients in which the diagnosis is not clear until

months have elapsed and the disease has progressed as expected, so new diagnostic tools

are actively being sought by those who treat and study this disease.

Surrogate Markers of Disease Progression in ALS

Several markers have been proposed for tracking disease progression in ALS and

some are used routinely in clinical care and treatment trials (Table 1.2).28 The revised

ALS Functional Rating Scale (ALSFRS-R) is a valid and reliable tool consisting of

questions pertaining to daily function.29 It has high construct validity and is used in

almost all clinical trials, although it may lack sensitivity for detecting progression that

does not result in changes in activities of daily living. Forced vital capacity (FVC),

maximal inspiratory pressure (MIP), and other measures of respiratory insufficiency are

also used routinely in clinical and research settings, but these surrogate markers of

disease progression also lack sensitivity, particularly in those who have not yet

experienced respiratory involvement.30 Finally, motor unit number estimation (MUNE)

is an electrodiagnostic technique that provides objective data of motor unit loss.31 It is

reliable and demonstrates rates of decline in ALS that compare favorably to other

biomarkers, but it is uncomfortable and its use has only been demonstrated in a small

subset of muscles. In addition, MUNE can be time consuming and is not used in routine

clinical practice.

6

Table 1.1. Current and potential biomarkers for diagnosis and tracking of disease progression in ALS.

Biomarker Used Routinely? ALS Functional Rating Scale29 Yes Forced Vital Capacity/Maximal Inspiratory Pressure30 Yes Electrodiagnostic Studies Motor unit number estimation31 Neurophysiological index32 Electrical impedance myography33 Phrenic nerve compound muscle action potential34

Yes No No No

Cerebrospinal fluid analyses TDP-4335 Tau protein36 S100beta37 sCD1437 Cystatin C38

No No No No No

Plasma analyses L-ferritin39 Monocyte chemoattractant 139 Granulocyte-macrophage colony stimulating factor39

No No No

Magnetic resonance image techniques Diffusion weighted image40 Diffusion tensor imaging40

No No

Other surrogate markers of disease progression have been developed for following

individuals with ALS (Table 1.2),32, 33, 37 but the ALSFRS, FVC, and MUNE are

employed most often, and a combination of these markers are typically used in clinical

trials as they have complementary characteristics.28 Ideally, future biomarkers for ALS

will be reliable, sensitive (even to pre-clinical changes), painless, quick, applicable to

different muscle groups that may be affected (and different sub-types of ALS), and

responsive to meaningful changes in disease progression. Such biomarkers will increase

the accuracy and decrease the length of clinical trials.40

7

Neuromuscular Ultrasound

Neuromuscular ultrasound involves the use of high-resolution ultrasound to image

peripheral nerves and muscles, which can assist in the diagnosis of a variety of

neuromuscular diseases.41 Its use was first described in the early 1980s in patients with

muscular dystrophy, but since then it has been used to improve diagnostic capabilities in

focal neuropathies, inherited neuropathies, inflammatory muscle diseases, and

autoimmune mediated neuropathies.42-46 In general, diseased muscle has increased

echogenicity and increased homogeneity of echotexture, and some diseases result in

muscle atrophy with others showing edema and hypervascularity.41 Diseased nerves

often enlarge, are hypoechoic, and may have increased vascularity.41 In addition to

providing information about muscle and nerve anatomy and pathophysiology,

neuromuscular ultrasound is also a promising technique because it is painless, does not

use radiation, is relatively inexpensive, is readily available, and often can be performed

rapidly.41 While it has been used to assess many conditions, neuromuscular ultrasound

has been studied only minimally in the evaluation of ALS.

Neuromuscular Ultrasound in ALS

There are several potential methods in which neuromuscular ultrasound could be used

to assess individuals with ALS, some which have been explored preliminarily and others

which have not. Muscle ultrasound has been evaluated in the motor neuron disease

spinal muscular atrophy (SMA) and in ALS, with typical echotexture findings listed in

8

Table 1.2.47-50 Muscle ultrasound has also been used to detect the presence of

fasciculations, with ultrasound

demonstrating higher sensitivity than both visual inspection and EMG.51 Three

longitudinal studies have examined muscle thickness, as measured by ultrasound, in

individuals with ALS, and all have demonstrated a small but statistically significant

decrease in muscle thickness over several months.52-54 Conversely, neuromuscular

ultrasound of peripheral nerves in those with motor neuron disease has not previously

been reported, and while autopsy studies have shown nerve root atrophy,55 there is a

surprising lack of any imaging studies confirming this finding in peripheral nerves in

vivo. Since peripheral nerve imaging has not previously been reported in ALS and

muscle imaging has only been preliminarily explored, this study was designed to explore

these two imaging targets further using high resolution neuromuscular ultrasound.

Study Design and Specific Aims

This project was designed as a pilot study to examine the use of neuromuscular

ultrasound as a potential tool for diagnosis and possibly as a surrogate marker of disease

Table 1.2 Neuromuscular Ultrasound Findings in Motor Neuron Disease

1. Increased muscle echogenicity 2. Increased muscle heterogeneity 3. Increased subcutaneous tissue thickness 4. Muscle atrophy 5. Increased subcutaneous tissue-to-muscle thickness ratio 6. Increased calf size 7. Long duration fasciculations

9

progression in those with ALS. Two questions were of specific interest. First, do

peripheral nerves carrying motor fibers change in size (either increase or decrease), as

measured with neuromuscular ultrasound, in individuals with ALS compared to controls?

Second, does neuromuscular ultrasound demonstrate muscle atrophy in those with ALS

compared to controls?

To address these questions, a prospective study with 20 individuals with ALS and 20

age and sex matched controls was designed. A specific effort was made to target and

enroll individuals with advanced weakness and atrophy of at least one upper extremity, so

this proof-of-concept pilot study would not be limited by the presence of subtle changes

in those early into the disease process. In all 40 individuals neuromuscular ultrasound

was performed to assess the following:

1. Cross-sectional area of the median nerve at the mid-point of the upper arm.

This site was chosen because it is a nerve that is commonly studied with

neuromuscular ultrasound, it carries motor fibers to many muscles in the distal

arm and hand, it is a site that is easy to visualize, and it is site at which the

nerve is not often compressed (as opposed to the wrist, where it is frequently

entrapped and causes carpal tunnel syndrome and nerve enlargement).

2. Cross-sectional area of the sural nerve 10 cm above the lateral malleolus.

This nerve was chosen because it is a pure sensory nerve that should not be

affected by the neurodegeneration that occurs in motor and mixed nerves in

ALS. It is also a nerve that is easily visualized with neuromuscular ultrasound

and is not frequently entrapped.

10

3. Thickness of the biceps brachii and brachialis muscle complex at the mid-

point of the upper arm.

It was hypothesized that there would be no difference in sural nerve area between the two

groups and there would be significant atrophy in the biceps/brachialis muscle complex in

patients with ALS. However, it was difficult to speculate whether the median nerve

would show an increase or decrease in size in ALS compared to controls. One line of

thought was that the nerve would increase in size because other neuropathic conditions,

such as entrapment, inflammatory neuropathies, and inherited neuropathies have all

demonstrated nerve enlargement as part of the disease process.44, 56, 57 This includes

processes that involve progressive axon death, such as CMT Type 2 and diabetic

polyneuropathy, although nerve enlargement is greater in demyelinating hereditary

polyneuropathies compared to axonal hereditary polyneuropathies.58, 59 Alternatively,

one might expect the median nerve to be smaller in those with ALS compared to controls,

since there is significant axon loss in ALS once distal atrophy is present,60 and autopsy

studies reveal thinning of nerve roots.55

These thoughts led to the development of the following Specific Aims:

Specific Aim 1. To determine if neuromuscular ultrasound measurement of the

median nerve in the upper arm can demonstrate measurable changes in nerve

cross-sectional area in 20 adults with ALS compared to 20 age and gender

matched controls.

11

Specific Aim 2. To determine if neuromuscular ultrasound measurement of the

biceps brachii/brachialis muscle complex can demonstrate measurable atrophy in

20 adults with ALS compared to 20 age and gender matched controls.

12

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diseases: a quantitative ultrasound study in 350 patients and review of the literature.

J Neurol Sci 1996; 143:46-56.

50. Arts IM, van Rooij FG, Overeem S, Pillen S, Janssen HM, Schelhaas HJ, Zwarts

MJ. Quantitative muscle ultrasonography in amyotrophic lateral sclerosis.

Ultrasound Med Biol 2008; 34:354-361.

51. Misawa S, Noto Y, Shibuya K, Isose S, Sekiguchi Y, Nasu S, Kuwabara S.

Ultrasonographic detection of fasciculations markedly increases diagnostic

sensitivity of ALS. Neurology 2011.

20

52. Arts IM, Overeem S, Pillen S, Schelhaas HJ, Zwarts MJ. Muscle ultrasonography to

predict survival in amyotrophic lateral sclerosis. J Neurol Neurosurg Psychiatry

2010.

53. Arts IM, Overeem S, Pillen S, Jurgen SH, Zwarts MJ. Muscle changes in

amyotrophic lateral sclerosis: A longitudinal ultrasonography study. Clin

Neurophysiol 2010.

54. Lee CD, Song Y, Peltier AC, Jarquin-Valdivia AA, Donofrio PD. Muscle

ultrasound quantifies the rate of reduction of muscle thickness in amyotrophic

lateral sclerosis. Muscle Nerve 2010; 42:814-819.

55. Konagaya M, Kato T, Sakai M, Kuru S, Matsuoka Y, Konagaya Y, Hashizume Y,

Tabira T. A clinical and pathological study of a Japanese case of Amyotrophic

Lateral Sclerosis/Parkinsonism-Dementia Complex with family history. J Neurol

2003; 250:164-170.

56. Wiesler ER, Chloros GD, Cartwright MS, Smith BP, Rushing J, Walker FO. The

use of diagnostic ultrasound in carpal tunnel syndrome. J Hand Surg [Am ] 2006;

31:726-732.

57. Zaidman CM, Al-Lozi M, Pestronk A. Peripheral nerve size in normals and patients

with polyneuropathy: an ultrasound study. Muscle Nerve 2009; 40:960-966.

58. Martinoli C, Schenone A, Bianchi S, Mandich P, Caponetto C, Abbruzzese M,

Derchi LE. Sonography of the median nerve in Charcot-Marie-Tooth disease. AJR

Am J Roentgenol 2002; 178:1553-1556.

21

59. Watanabe T, Ito H, Sekine A, Katano Y, Nishimura T, Kato Y, Takeda J, Seishima

M, Matsuoka T. Sonographic evaluation of the peripheral nerve in diabetic patients:

the relationship between nerve conduction studies, echo intensity, and cross-

sectional area. J Ultrasound Med 2010; 29:697-708.

60. Swash M, Ingram D. Preclinical and subclinical events in motor neuron disease. J

Neurol Neurosurg Psychiatry 1988; 51:165-168.

22

CHAPTER II

PERIPHERAL NERVE AND MUSCLE ULTRASOUND IN AMYOTROPHIC

LATERAL SCLEROSIS The following manuscript was published in the journal Muscle & Nerve September,

2011 and is reprinted with permission. Stylistic variations are due to requirements of the

journal. MS Cartwright performed the experiments, data analysis, and prepared the

manuscript. Drs. Walker and Caress acted in advisory and editorial capacities, and Ms.

Griffin assisted with statistical analyses.

23

Peripheral Nerve and Muscle Ultrasound in Amyotrophic Lateral Sclerosis Michael S. Cartwright, MD; Francis O. Walker, MD; Leah P. Griffin, MS; James B. Caress, MD

1. Department of Neurology, Wake Forest University School of Medicine, Winston-Salem, NC 27157

2. Division of Public Health Sciences, Department of Biostatistics, Wake Forest University School of Medicine, Winston-Salem, NC 27157

Disclosure: Drs. Cartwright, Caress, and Walker, and Ms. Griffin have nothing to disclose. Financial Support: Dr. Cartwright had a Clinical Research Training Grant from the Muscular Dystrophy Association and has funding from the NIH/NINDS (1K23NS062892) to study neuromuscular ultrasound. Running Title: Ultrasound in ALS Contact: Michael S. Cartwright, MD Department of Neurology Wake Forest University School of Medicine Main Floor Reynolds Tower Winston-Salem, NC 27157 Phone: 336-716-5177 Fax: 336-716-7794 Email: [email protected]

24

Abstract

Introduction: High-resolution ultrasound has been used to evaluate several

neuromuscular conditions, but it has only been used on a limited basis in ALS patients. It

has not been used to assess their peripheral nerves. This study was designed to use

neuromuscular ultrasound to investigate nerve cross-sectional area and muscle thickness

in ALS.

Methods: Twenty individuals with ALS and 20 matched controls underwent

neuromuscular ultrasound to measure the cross-sectional area of their median and sural

nerves and the thickness of their biceps/brachialis muscle complex.

Results: The cross-sectional area of the median nerve in the mid-arm was smaller in the

ALS group than controls (10.5mm2 vs. 12.7mm2, p=0.0023), but no difference was seen

in the sural nerve (4.5mm2 vs. 5.0mm2, p=0.1927). The ALS group also had thinner

biceps/brachialis than controls (2.1cm vs. 2.9cm, p=0.0007).

Discussion: Neuromuscular ultrasound demonstrates nerve and muscle atrophy in ALS

and should be further explored as a disease biomarker.

Key Words: Amyotrophic lateral sclerosis, ultrasound, median nerve, sural nerve, muscle

25

Introduction

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease for

which there is neither cure nor treatment to significantly slow the progressive weakness.

Multiple obstacles hinder the ability to study and effectively treat ALS, one of which is

the limited number of tests available to assist in the early diagnosis and monitoring of

disease progression. Diagnosis of ALS is not typically made until 9-10 months after the

onset of symptoms,1 and the diagnosis is based on history and clinical examination.

Excluding other causes of progressive weakness through the use of blood work, central

nervous system imaging, and electrodiagnostic studies helps support the diagnosis of

ALS.2 Monitoring disease progression can be done with manual strength testing,

assessment of forced vital capacity (FVC), the ALS functional rating scale (ALSFRS),

and motor unit number estimation (MUNE), but all of these techniques have limitations,

including lack of responsiveness, operator variability, and pain.3

Over the past decade, high-frequency diagnostic ultrasound of peripheral nerve and

muscle has emerged as a tool to assist in the evaluation of individuals with

neuromuscular conditions, and it has become known as neuromuscular ultrasound.4 This

technique has only been assessed on a limited basis in those with ALS, and the few

studies of neuromuscular ultrasound in ALS evaluated muscle and did not assess nerve

characteristics.5-8 In addition, there are surprisingly few studies of peripheral nerve

caliber and muscle thickness using other imaging modalities or macroscopic analysis at

autopsy in individuals with ALS.9 There exist reports of nerve root atrophy in ALS, but

the literature is sparse and does not examine nerve caliber in the limbs.10 Therefore, this

26

study was undertaken to use neuromuscular ultrasound to compare nerve caliber and

muscle thickness in individuals with ALS and age and gender matched controls.

In other systemic conditions affecting the peripheral nerves, such as diabetes,

multifocal motor neuropathy, Charcot-Marie Tooth disease, and chronic inflammatory

demyelinating polyneuropathy, neuromuscular ultrasound has demonstrated increased

nerve cross-sectional area.11-14 It was unknown if a similar finding would be detected in

ALS, or if nerve cross-sectional area would be reduced because of progressive axon loss.

We hypothesized that muscle ultrasound would demonstrate atrophy.

27

Materials and Methods

Participants

Prior to the collection of data, this study was approved by the Institutional Review

Board at Wake Forest University School of Medicine, and all participants provided

signed informed consent. Initially, 20 patients with “probable,” “laboratory-supported

probable,” or “definite” ALS based on Revised El Escorial Criteria were recruited.15

These participants were diagnosed with ALS by experienced ALS clinicians (MSC and

JBC), and each participant had extremity strength testing (performed by the diagnosing

physicians and graded on Medical Research Council scale), FVC (performed by a

respiratory therapist and recorded as “percent of predicted”), and ALSFRS (recorded as

the “global score”)16 on the same day the ultrasound was performed. The number of

months since the onset of symptoms, weight, height, and race were also recorded.

Once 20 participants with ALS were recruited and assessed, 20 age and gender

matched controls were recruited. The control group included friends and family of the

ALS participants and medical center employees. Controls were excluded if they reported

any symptoms referable to the nervous system. Controls underwent ultrasound and

strength testing, and their weight, height, and race were recorded.

Ultrasound

All 40 participants (20 with ALS and 20 controls) underwent neuromuscular

ultrasound, performed by the same physician (MSC). A Biosound MyLab 25 (Esaote

Group, Genoa, Italy) with an 18 MHz linear array transducer was used for each study.

The participants were in the supine or seated position, with the ultrasonographer facing

28

the patient, and all imaging was performed bilaterally. First, the mid-point of the arm

was identified at the half-way mark between the medial epicondyle and the axilla, and the

median nerve was imaged at this site (Figure 2.1A). This point was selected for study

because the median nerve is commonly assessed with neuromuscular ultrasound,

reference values are available for the median nerve at this site,17 and it is an uncommon

site of entrapment. The transducer was placed so that a cross-sectional view of the

median nerve was obtained. The cross-sectional area of the nerve was measured using the

trace function on the ultrasound device and tracing along the hyperechoic rim of the

nerve, erring just to the inside of the rim (Figure 2.1B). This was performed three times,

and all three measurements were then averaged to obtain a final median nerve cross-

sectional area measurement. The right and left median nerves were recorded separately,

and the two were averaged to obtain a mean median nerve cross-sectional area for each

participant.

Figure 2.1. Image A demonstrates the transducer position used to visualize the median nerve in the mid-arm and obtain the ultrasound image shown in panel B. The arrow points to the median nerve (outlined in white), and the arrowhead points to the adjacent brachial artery. The “H” is placed over the humerus.

29

Next, the sural nerve was assessed at 10 cm above the lateral malleolus (Figure 2.2A).

The transducer was again positioned to obtain a cross-sectional view of the nerve, and an

area measurement was obtained (Figure 2.2B). This was performed three times, and

mean values were recorded for each side. A total sural nerve mean cross-sectional area

was obtained by averaging both sides together. The sural nerve was selected because

there are reference values available and it is a pure sensory nerve that should not be

affected by ALS.18

Figure 2.2. Image A demonstrates the transducer position used to visualize the sural nerve and obtain the ultrasound image shown in panel B. The arrow points to the sural nerve (outlined in white), which is located between two superficial veins.

Finally, we returned to the mid-point of the arm to measure the thickness of the biceps

brachii and brachialis muscle complex. The transducer was placed over the anterior

portion of the mid-arm, with the elbow extended, to obtain a cross-sectional view of the

arm (Figure 2.3A). Using the straight line measuring function on the ultrasound device,

the thickness of the biceps/brachialis complex was measured from the most superficial

portion of the muscle to the hyperechoic reflection of the humerus (Figure 2.3B). Care

was taken to minimize pressure from the transducer on the muscle to avoid muscle

30

compression. This measurement was repeated twice to obtain a mean value for each side,

and the two sides were averaged in each participant to obtain an overall mean

biceps/brachialis thickness value.

Figure 2.3. Image A demonstrates the probe position used to visualize the biceps/brachialis muscle complex shown in panel B. The superficial extent of the muscle and the echogenic reflection from the humerus are marked with plus signs (+).

Statistical Analyses

Descriptive statistics include means and ranges for continuous measures and counts

and percentages for categorical measures. All statistical tests were two-sided, and

significance was determined at the 0.05 probability level. Comparisons between the ALS

and control groups were done with two-tailed t-tests for continuous variables and chi-

squared tests for categorical variables. Pearson product-moment correlation coefficients

were calculated to determine correlation between ultrasonographic parameters and

strength testing, FVC, ALSFRS, and months since disease onset.

31

Results

Twenty participants with ALS and 20 controls were included in this study. No

significant differences in age, gender, race, height, weight, or body mass index (BMI)

were noted between the two groups (Table 2.1). The 20 individuals with ALS had

symptoms for an average of 25.1 months prior to enrollment in this study, and their mean

FVC was 62.3% and the ALSFRS was 30.5 (Table 2.2).

Table 2.1 Demographics Variable Controls

n = 20 ALS Patients

n = 20 p-value

Mean Age (range) 58.1 (42 – 76) 58.4 (40 – 71) 0.9231 Gender (male) 10 (50%) 10 (50%) 1.0000 Race (Caucasian) 20 (100%) 19 (95%) 0.3112 Mean Height (range) 66.7 (61 – 75) 67.1 (61 – 71) 0.7140 Mean Weight (range) 171.6 (135 – 235) 162.3 (117 – 212) 0.2984 Mean BMI (range) 27.3 (20.9 – 39.5) 25.4 (19.3 – 33.8) 0.2090

Table 2.2 ALS Participant Characteristics Variable Mean (range) FVC (%) 62.3 (20 – 99)

ALSFRS 30.5 (12 – 48)

Months Since Onset 25.1 (6 – 60)

Significant differences were found when comparing median nerve cross-sectional area

and biceps/brachialis thickness between the two groups, and these differences were found

when using just the left arm and the total values for each individual (Table 2.3). The total

median nerve area was larger in controls (12.7 mm2 vs. 10.5 mm2, p = 0.0023), and the

total muscle thickness was greater in controls (2.9 cm vs. 2.1 cm, p = 0.0007). No

32

differences were noted when comparing the sural nerve cross-sectional area between the

two groups (Table 2.3).

Table 2.3 Ultrasonographic Comparisons between ALS Patients and Controls. Variable Controls

n = 20 Mean (range)

ALS Patients n = 20

Mean (range)

p-value

Left Median Area (mm2) 12.6 (9.5 – 15.0) 9.9 (7.0 – 15.0) 0.0004 Average Median Area (mm2) 12.7 (9.3 – 16.3) 10.5 (7.0 – 15.5) 0.0023 Left Sural Area (mm2) 5.0 (3.0 – 8.0) 4.5 (2.0 – 7.0) 0.1858 Average Sural Area (mm2) 5.0 (3.0 – 8.0) 4.5 (2.5 – 6.5) 0.1927 Left Muscle Thickness (cm) 3.0 (1.7 – 4.2) 2.0 (0.4 – 3.7) 0.0001 Average Muscle Thickness (cm) 2.9 (2.0 – 4.3) 2.1 (0.4 – 3.8) 0.0007

Statistically significant correlation was only seen when comparing the thickness of the

biceps/brachialis muscle complex to the MRC-graded strength testing of the biceps

muscle (r=0.5062, p=0.0228), although the correlation between the cross-sectional area

of the left median nerve and the strength of the abductor pollicis brevis (APB) muscle

approached statistical significance (r=0.4206, p=0.0648). No significant correlation was

seen when comparing the total median nerve cross-sectional area to the FVC, ALSFRS or

months since onset, or when comparing the total biceps/brachialis thickness to the FVC,

ALSFRS or months since onset (Table 2.4).

33

Table 2.4 Correlation Between Ultrasonographic Parameters and Other Variables Comparison Correlation

Coefficient p-value

Average Median Area vs. FVC -0.0075 0.9750 Average Median Area vs. ALSFRS 0.1280 0.5908 Left Median Area vs. Left APB strength 0.4206 0.0648 Muscle Thickness vs. Biceps Strength 0.5062 0.0228 Average Muscle Thickness vs. FVC 0.3721 0.1062 Average Muscle Thickness vs. ALSFRS 0.3325 0.1520 Average Median Area vs. Months since onset -0.3106 0.1825 Average Muscle Thickness vs Months since onset -0.0806 0.7356

Discussion

This study compared nerve cross-sectional area measurements in individuals with

ALS to age and gender matched controls. The 20 individuals in the control group

matched well with the ALS group, with no significant differences in the groups with

respect to age, gender, race, height, weight, or BMI. When the ultrasonographic cross-

sectional area of the median nerve was compared between the two groups, those with

ALS had significantly smaller median nerves than controls (12.7 mm2 in controls vs. 10.5

mm2 in ALS, p=0.0023), but no difference was noted in sural nerve cross-sectional area

between the groups. The cause of the median nerve difference is not definitely known,

but the most likely explanation is that progressive motor axon loss, which occurs in ALS,

results in mild atrophy of the nerve. Interestingly, a previous study to establish reference

values for median nerve cross-sectional area found an average area of 8.9 mm2 at the

mid-arm, which is much smaller than the median nerve area of controls in this study and

smaller than the area in those with ALS.17 At least some of this discrepancy may be

explained by age differences between the studies. The mean age in this study was 13

34

years older than in the study to establish reference values (mean age of 58 years in the

current study and 45 in the reference values study), and it has been shown that median

nerve area positively correlates with age.17 It is also possible that differences in

ultrasound devices, transducer frequency, or examiner technique could have contributed

to the differences in median nerve cross-sectional area between the two studies.

The other significant difference between the two groups occurred when the thickness

of the biceps/brachialis muscle complex was compared; the control group had thicker

muscles (2.9 cm vs. 2.1 cm, p=0.0007). A difference in muscle thickness between the

two groups was expected, because those with ALS demonstrate visible muscle atrophy.

It was unknown how large a difference would be detected by assessing just one muscle

group, because there is variability in the body region affected in individuals with ALS.

The difference noted in this study was statistically significant, and those with ALS had

biceps/brachialis thickness less than 75% that of controls. This difference would likely

be even more striking if muscle volume, rather than thickness, was measured.

One objective of this study was to determine if neuromuscular ultrasound revealed

peripheral nerve or muscle abnormalities obvious enough to assist in the diagnosis of

ALS. While statistically significant differences were seen in median nerve cross-

sectional area and biceps/brachialis muscle thickness between the ALS and control

groups, the absolute differences were either not unique to ALS or difficult to apply as

universal diagnostic criteria. For example, decreased muscle thickness can be seen in

other neuropathic and chronic myopathic conditions, and the affect of age, body habitus,

and other factors on nerve area prohibits the establishment of a single cut-off level for the

detection of median nerve atrophy in ALS. Despite these limitations and the inability to

35

establish universal diagnostic criteria, neuromuscular ultrasound can assist in the

diagnosis of ALS now that the typical findings are known. Neuromuscular ultrasound

findings consistent with ALS include normal to decreased nerve cross-sectional area (as

opposed to nerve enlargement described in demyelinating polyneuropathies12), muscle

atrophy (as opposed to muscle edema and swelling, which have been described in acute

inflammatory myopathies19), and the presence of fasciculations.5

The second objective was to initiate exploration of neuromuscular ultrasound as a

surrogate marker of disease progression in ALS. While this study did not have a

longitudinal component to directly address this issue, we showed that both median nerve

cross-sectional area and muscle thickness are decreased in those with ALS, indicating

they could be further explored as surrogate markers of disease progression. In addition,

thickness of the biceps/brachialis complex correlated with strength testing, which has

been used as a marker of disease progression. There is one recent study in which muscle

ultrasound was examined over 6 months as a potential marker of disease progression in

22 individuals with ALS, and the authors concluded there was too much variability in

their measures for it to serve as an effective marker of disease progression.8 However,

their study had limitations, including the use of two different ultrasound devices, not all

participants being assessed at all time points, repeated measures statistical analyses not

being performed, use of a composite ultrasound score from multiple different muscle

groups (not including a distal intrinsic hand or foot muscle), and a focus on the presence

of fasciculations. Conversely, another recent study of muscle ultrasound in spinal

muscular atrophy showed that calculating a ratio of echogenicity in subcutaneous tissue

compared to muscle could discriminate between degrees of disease severity, and the

36

authors concluded that muscle ultrasound could potentially serve as a marker of

progression in this motor neuron disease.20 Given the results in our study, as well as the

limitations in other studies, muscle ultrasound as a surrogate marker of disease

progression deserves further investigation, and nerve cross-sectional area could also be

studied in a longitudinal manner. The likely small changes in nerve cross-sectional area

over time would make it necessary to closely standardize the ultrasonographic

examination, and it may be helpful to study a larger nerve, such as the sciatic.

While some limitations occurred in our study, including small sample size, the

ultrasonographer not being blinded to participant group, no measures of muscle or nerve

echotexture, and a lack of longitudinal data collection, it did permit an initial

investigation into neuromuscular ultrasound measurements in ALS and demonstrated

nerve and muscle atrophy in ALS compared to controls. Future investigations using

neuromuscular ultrasound to evaluate individuals with ALS are warranted. These could

include longitudinal data, study of other muscles such as the diaphragm and distal

extremity muscles, muscle volume measurements, and quantitative assessments of nerve

and muscle echotexture.

37

Reference List

1. Kraemer M, Buerger M, Berlit P. Diagnostic problems and delay of diagnosis in

amyotrophic lateral sclerosis. Clin Neurol Neurosurg 2010; 112:103-105.

2. Shook SJ, Pioro EP. Racing against the clock: recognizing, differentiating,

diagnosing, and referring the amyotrophic lateral sclerosis patient. Ann Neurol

2009; 65 Suppl 1:S10-S16.

3. de Carvalho M, Costa J, Swash M. Clinical trials in ALS: a review of the role of

clinical and neurophysiological measurements. Amyotroph Lateral Scler Other


4. Walker FO, Cartwright MS, Wiesler ER, Caress J. Ultrasound of nerve and muscle.

Clin Neurophysiol 2004; 115:495-507.






2010.

7. Yoshioka Y, Ohwada A, Sekiya M, Takahashi F, Ueki J, Fukuchi Y.

Ultrasonographic evaluation of the diaphragm in patients with amyotrophic lateral

sclerosis. Respirology 2007; 12:304-307.

38



Neurophysiol 2010.

9. Hanyu N, Oguchi K, Yanagisawa N, Tsukagoshi H. Degeneration and regeneration

of ventral root motor fibers in amyotrophic lateral sclerosis. Morphometric studies

of cervical ventral roots. J Neurol Sci 1982; 55:99-115.

10. Wohlfart G, Swank R. Pathology of amyotrophic lateral sclerosis. Arch Neurol

Psychiat 1941; 46:783-799.

11. Watanabe T, Ito H, Sekine A, Katano Y, Nishimura T, Kato Y, Takeda J, Seishima

M, Matsuoka T. Sonographic evaluation of the peripheral nerve in diabetic patients:

the relationship between nerve conduction studies, echo intensity, and cross-

sectional area. J Ultrasound Med 2010; 29:697-708.





Diagnostic nerve ultrasound in Charcot-Marie-Tooth disease type 1B. Muscle

Nerve 2009; 40:98-102.



39

15. Brooks BR, Miller RG, Swash M, Munsat TL. El Escorial revisited: revised criteria

for the diagnosis of amyotrophic lateral sclerosis. Amyotroph Lateral Scler Other


16. Cedarbaum JM, Stambler N, Malta E, Fuller C, Hilt D, Thurmond B, Nakanishi A.

The ALSFRS-R: a revised ALS functional rating scale that incorporates

assessments of respiratory function. BDNF ALS Study Group (Phase III). J Neurol

Sci 1999; 169:13-21.

17. Cartwright MS, Shin HW, Passmore LV, Walker FO. Ultrasonographic Reference

Values for Assessing the Normal Median Nerve in Adults. J Neuroimaging 2008.

18. Cartwright MS, Passmore LV, Yoon JS, Brown ME, Caress JB, Walker FO. Cross-

sectional area reference values for nerve ultrasonography. Muscle Nerve 2008;

37:566-571.

19. Weber MA. Ultrasound in the inflammatory myopathies. Ann N Y Acad Sci 2009;

1154:159-170.

20. Wu JS, Darras BT, Rutkove SB. Assessing spinal muscular atrophy with

quantitative ultrasound. Neurology 2010; 75:526-531.

40

CHAPTER III

DISCUSSION

This is the seventh published study in which neuromuscular ultrasound was used

specifically to evaluate individuals with ALS (Table).1-7 Of the previous studies, five

used high-resolution ultrasound to evaluate peripheral muscle size, echotexture, and/or

fasciculations, one studied bulbar musculature and function, and one assessed diaphragm

characteristics. None of the previous studies assessed ultrasonographic characteristics of

peripheral nerves.

Muscle Ultrasound in ALS

In this study, the thickness of the biceps brachii and brachialis muscle complex was

measured by placing the ultrasound transducer at the anterior portion of the mid-arm to

obtain a cross-sectional view of the biceps/brachialis muscle complex. The thickness of

this complex was obtained using the measuring tool function on the ultrasound device,

and care was taken to avoid compressing the tissue as the image was obtained. Those

with ALS had a mean muscle thickness of 2.0 cm in the left arm and 2.1 cm when the left

and right arms were averaged, whereas the controls had a left arm thickness of 3.0 cm

and a left/right average thickness of 2.9 cm. In addition to being statistically significant

(p = 0.0007), the difference seen in muscle thickness between those with ALS and

controls was large enough to visualize without relying on overly sensitive measurement

techniques, as the muscle thickness in ALS patients was less than 75% the thickness seen

41

in controls. This was expected, as ALS causes visible atrophy, and four previous studies

have used ultrasound to demonstrate some degree of muscle atrophy in ALS.2, 4-6 The

current study showed a significant correlation between biceps/brachialis thickness and

biceps strength (0.5062, p = 0.0228), but no correlation between muscle thickness and

ALSFRS-R or FVC.

Table 3.1. Neuromuscular Ultrasound Studies in ALS

Year Author Was Extremity Muscle Atrophy Present?

Were Fasciculations Assessed?

Other Assessments

2011 Misawa S et al.7 Not studied Yes; US was more sensitive than exam and EMG

None

2011 Arts IM et al.5 Yes; muscle size declined over time

Yes Muscle EI increased over time

2011 Arts IM et al.6 Yes; muscle size declined over time

Yes Muscle EI increased over time

2010 Lee CD et al.4 Yes; muscle size declined over time

Yes Muscle EI without change

2010 Tamburrini et al.3 Not studied No Swallowing evaluated

2008 Arts IM et al.2 Yes Yes Muscle EI increased at baseline

2007 Yoshioka Y et al.1 Not studied No Diaphragm paralysis noted

42

None of the previous studies of muscle thickness used matched controls, but two did

assess the progression of atrophy over time.4, 6 Both studies with longitudinal

components showed that muscle thickness decreased significantly in those with ALS over

several months. For example, Lee et al. showed the biceps/brachialis complex decreased

in thickness by 0.66 mm per month in those with ALS (p = 0.0014), and this correlated

with a summed strength score, but not the ALSFRS.4 In the study by Arts et al. the

progressive atrophy did not correlate with a summed strength score nor the ALSFRS.6 In

addition to assessing the biceps/brachialis complex, these previous studies also assessed

the thickness of the sternocleidomastoid, wrist flexor, wrist extensor, quadriceps, and

tibialis anterior muscles.

After completing our study, we were encouraged by the ability to detect muscle

atrophy with neuromuscular ultrasound, but it was clear that several methodological

changes could be made to improve the sensitivity of ultrasonographic measures of muscle

thickness. First, inclusion of distal muscles in the hands and feet, which are often

affected early in ALS, would be beneficial. Second, extreme precision needs to be

exercised in marking and measuring the exact same site each time, and this could be

accomplished with a small, permanent skin marking to guide transducer placement in

subsequent visits. Third, ultrasound settings, including gain, time gain compensation,

depth, and focus need to be standardized and applied in the same manner for each muscle

studied. Finally, it may be more sensitive, and less prone to error based on transducer

position, if muscle area or even volume was calculated, instead of depth, as the depth can

be changed with subtle pressured applied to the transducer.

43

In this study the decision was made to not assess echotexture, but the four previous

studies did evaluate muscle echointensity using gray-scale analyses. In those studies, the

ultrasound images were downloaded and then assessed using software such as Adobe

Photoshop to obtain mean gray-scale numbers (termed echointensity), with a range of 0

(black) to 255 (white). Two studies, both by the same group, generated results that

suggested echointensity could be used to prognosticate and accurately follow ALS

patients over time,5, 6 but one study showed no trend in echointensity over 6 months.4

Our experience with echotexture analysis of muscle ultrasound images is that it is

variable, and it changes based upon factors such as transducer type, angle of insonation,

gain, and depth, and therefore it is a difficult technique for analyzing subtle changes over

time. Recent studies have confirmed this, and demonstrated that transducer selection can

significantly affect echotexture analyses.8 However, gray-scale analysis is a field that is

evolving, and future developments in image processing and analysis could improve the

reliability of muscle echotexture measurements.

The final use of muscle ultrasound in the assessment of those with ALS has been to

detect fasciculations. The first report of ultrasound for the detection of fasciculations was

in 1988, and it was demonstrated to be a sensitive technique as it allowed for scanning of

multiple muscles, painlessly and efficiently.9 Since then other studies have confirmed the

sensitivity of ultrasound for the detection fasciculations,2, 10 and very recent data from

Misawa et al. have demonstrated that the addition of ultrasound for the detection of

fasciculations greatly increases the sensitivity of the Awaji criteria for the diagnosis of

ALS (Figure 3.1).7 Taken together, these studies suggest that muscle ultrasound is

44

sensitive for the detection of fasciculations and that it greatly increases the diagnostic

sensitivity of the currently used diagnostic criteria.

Figure 3.1. This shows that the proportion of people in the “probable” and “definite” category by El Escorial (EE) criteria was 48% and this increased to 79% when the Awaji criteria, along with the use of EMG and ultrasound, was applied.7

Nerve Ultrasound in ALS

Unlike muscle ultrasound, nerve ultrasound has not been previously examined as a

diagnostic technique in individuals with ALS. In this current study, ultrasound was used

to examine the cross-sectional area of the median nerve in the mid-portion of the upper

45

arm. In 20 individuals with ALS, the mean cross-sectional area of the median nerve was

10.5 mm2, which was significantly smaller (p = 0.0023) than the 12.7 mm2 mean seen in

20 age and sex matched controls. In addition, no difference in cross-sectional area was

seen when the sural nerve was compared between these two groups (p = 0.1927). While

the median nerve in the upper arm was statistically significantly smaller in those with

ALS, the absolute difference in size between the two groups was not large and there was

overlap in the range of nerve sizes seen between the two groups. This indicates that

neuromuscular ultrasound as a tool to detect nerve atrophy is unlikely to be sensitive

enough to assist in the diagnosis of ALS. However, this finding is quite helpful because

other conditions that mimic ALS, such as multifocal motor neuropathy and chronic

inflammatory demyelinating polyneuropathy, are associated with increased cross-

sectional area of peripheral nerves.11, 12 It should also be noted that median nerve area

did not correlate with ALSFRS or FVC, but it did approach statistical significance in

correlating with strength of the abductor pollicis brevis muscle (0.4206, p = 0.0648).

Neuromuscular Ultrasound in the Diagnosis of ALS

Given the findings of the current study, as well as the results of the previous studies

listed in Table 3.1, neuromuscular ultrasound is a technique that can be considered to

improve diagnostic accuracy in the evaluation of individuals suspected to have ALS. If

used, based on the current state of knowledge, the highest yield parameters would be to

assess nerve cross-sectional area and muscle to detect fasciculations. Specifically,

neuromuscular ultrasound should first be used to assess the extremity in which weakness

46

initially occurred or is most pronounced. In this extremity, the major nerve branches

(median, ulnar, and radial in the arm and sciatic, tibial, and fibular in the leg) should be

scanned with the transducer positioned to obtain cross-sectional images. Several

measurements should be obtained along the length of each nerve, and if the upper

extremity is assessed the brachial plexus should be imaged as well, as it is often enlarged

in multifocal motor neuropathy and chronic inflammatory demyelinating

polyneuropathy.11, 13 Next, at least one distal and one proximal muscle should be

assessed in the extremity of interest for the presence of fasciculations. The transducer

should be oriented to obtain a cross-sectional view of a large segment of the muscle and

imaging of each region should last for at least 10 seconds. Finally, the other extremities,

as well as the genioglossus and thoracic paraspinal muscles, should be assessed in the

same manner, looking for the presence of fasciculations. It may be appropriate to

perform the ultrasonographic evaluation first, as it can then be used to guide the

electrodiagnostic study and perhaps limit the number of electrical stimulations from

nerve conduction studies and EMG needle sticks needed.

Future Directions

Further exploration of neuromuscular ultrasound for the diagnosis, prognosis, and

tracking of disease progression in ALS is needed, and a single large, prospective, multi-

site study could address several questions. One potential design would be to invite all

individuals referred to select ALS Center for possible ALS to undergo a neuromuscular

ultrasound evaluation (Figure 3.2). Close to 10% of those referred to ALS Centers are

47

ultimately diagnosed with an ALS mimic,14 so this design would enroll individuals with

ALS and those with conditions that mimic ALS. After the typical evaluation was

performed, including a thorough history, physical examination, and electrodiagnostic

evaluation, the participant would undergo a neuromuscular ultrasound examination by a

sonographer blinded to all clinical and electrodiagnostic information. The neuromuscular

ultrasound examination would be standardized and include peripheral nerve cross-

sectional areas at several sites in the weakest extremity; precise muscle size

measurements at distal and proximal sites in the arms and legs (area instead of depth,

when feasible); evaluation for fasciculations in the genioglossus, paraspinals, arms and

legs; and diaphragm thickness and excursion. Those with confirmed ALS would then be

followed every 3 months for the next 2 years with serial muscle size measurements of the

distal and proximal upper and lower extremity muscles. This design would allow for

comparison of all parameters between those with ALS and those with ALS mimics,

which is a design that would prevent the introduction of spectrum bias. Prospective data

collection and blinding of the ultrasonographer would also fulfill STARD criteria for the

complete and accurate reporting of tests of diagnostic accuracy.15 It would also allow

creation of statistical models to determine which neuromuscular ultrasound parameters

best predict prognosis. Finally, serial measurements of muscle size would permit

calculation of typical atrophy rates, which could then be used as surrogate markers of

disease progression. If this type of study was performed at approximately 10 ALS

Centers it could likely recruit at least 100 participants in a year,16 and a multi-site design

would allow for comparison of neuromuscular ultrasound techniques across sites, since

components of ultrasonographic examinations are operator dependent.

48

Figure 3.2. Study design to assess the diagnostic accuracy, prognostic ability, and usefulness as a surrogate marker of disease progression of neuromuscular ultrasound in individuals with ALS.

US

ALS confirmed through routine clinical examination

Diagnosed with ALS mimic

Individuals referred for possible ALS

2 year follow-up; muscle US every 3 months

Nerve area, muscle size, and presence of fasciculations compared

49

REFERENCES

1. Yoshioka Y, Ohwada A, Sekiya M, Takahashi F, Ueki J, Fukuchi Y.

Ultrasonographic evaluation of the diaphragm in patients with amyotrophic lateral

sclerosis. Respirology 2007; 12:304-307.




3. Tamburrini S, Solazzo A, Sagnelli A, Del VL, Reginelli A, Monsorro M, Grassi R.

Amyotrophic lateral sclerosis: sonographic evaluation of dysphagia. Radiol Med

2010; 115:784-793.

4. Lee CD, Song Y, Peltier AC, Jarquin-Valdivia AA, Donofrio PD. Muscle

ultrasound quantifies the rate of reduction of muscle thickness in amyotrophic

lateral sclerosis. Muscle Nerve 2010; 42:814-819.



2010.



Neurophysiol 2010.

50

7. Misawa S, Noto Y, Shibuya K, Isose S, Sekiguchi Y, Nasu S, Kuwabara S.

Ultrasonographic detection of fasciculations markedly increases diagnostic

sensitivity of ALS. Neurology 2011.

8. Hobson-Webb LD, Mhoon JT, Juel VC. Effect of transducer frequency on muscle

luminosity ratio. Muscle Nerve 2011; 44:612-613.

9. Reimers CD, Muller W, Schmidt-Achert M, Heldwein W, Pongratz DE.

[Sonographic detection of fasciculations]. Ultraschall Med 1988; 9:237-239.

10. Scheel AK, Toepfer M, Kunkel M, Finkenstaedt M, Reimers CD. Ultrasonographic

assessment of the prevalence of fasciculations in lesions of the peripheral nervous

system. J Neuroimaging 1997; 7:23-27.






13. Abrahams S, Goldstein LH, Simmons A, Brammer M, Williams SC, Giampietro V,

Leigh PN. Word retrieval in amyotrophic lateral sclerosis: a functional magnetic

resonance imaging study. Brain 2004; 127:1507-1517.

51

14. Traynor BJ, Codd MB, Corr B, Forde C, Frost E, Hardiman O. Amyotrophic lateral

sclerosis mimic syndromes: a population-based study. Arch Neurol 2000; 57:109-

113.

15. Bossuyt PM, Reitsma JB, Bruns DE, Gatsonis CA, Glasziou PP, Irwig LM, Moher

D, Rennie D, de Vet HC, Lijmer JG. The STARD statement for reporting studies of

diagnostic accuracy: explanation and elaboration. Ann Intern Med 2003; 138:W1-

12.

16. Al-Chalabi A, Shaw PJ, Young CA, Morrison KE, Murphy C, Thornhill M, Kelly J,

Steen IN, Leigh PN, Ukmnd-Licals OB. Protocol for a double-blind randomised

placebo-controlled trial of Lithium Carbonate in patients with Amyotrophic Lateral

Sclerosis (LiCALS) [EudraCT number: 2008-006891-31]. BMC Neurol 2011;

11:111.

52

CURRICULUM VITAE

NAME: Michael S. Cartwright CURRENT ACADEMIC TITLE: Assistant Professor ADDRESS:

Department of Neurology, Reynolds Tower Wake Forest School of Medicine Winston-Salem, NC 27157 Phone: 336-716-5177 Fax: 336-716-2810 Email: [email protected] EDUCATION: 1994-1998 Wake Forest University Bachelor of Science in Biology Summa Cum Laude

Phi Beta Kappa

1998-2002 Wake Forest School of Medicine Doctor of Medicine Alpha Omega Alpha

2006-Present Wake Forest School of Medicine Master of Science in Health Science Research POSTDOCTORAL TRAINING:

2002-2003 Internship in Internal Medicine Wake Forest University Baptist Medical Center

2003-2005 Residency in Neurology

Wake Forest University Baptist Medical Center

2005-2006 Chief Residency in Neurology Wake Forest University Baptist Medical Center

2006-2008 MDA Clinical Research Training Fellowship Focus in Neuromuscular Disease Wake Forest University Baptist Medical Center PROFESSIONAL LICENSURE: 2006-Present State of North Carolina

53

BOARD CERTIFICATION: 2007-Present Diplomat, American Board of Psychiatry and Neurology

2009-Present Diplomat, American Board of Electrodiagnostic Medicine (with recognition for scoring in top 10% on certification examination)

ACADEMIC APPOINTMENTS: 2006-2008 Instructor in Neurology Wake Forest School of Medicine 2008-Present Assistant Professor in Neurology Wake Forest School of Medicine 2010-Present Cross-appointment in Center for Worker Health Wake Forest School of Medicine 2011-Present Cross-appointment in Family Medicine, Sports Medicine Section Wake Forest School of Medicine EMPLOYMENT:

1993-2000 Tennis Instructor Rochester, MN Indoor and Outdoor Clubs

1996-1997 Teaching Assistant Aide

Wake Forest University

1996-1998 Academic Tutor Wake Forest University

PROFESSIONAL APPOINTMENTS AND ACTIVITIES: Ad hoc reviewer for:

• Prinses Beatrix Fonds, Funding Agency in the Netherlands • American Journal of Critical Care • Archives of Neurology • Archives of PMR • Atherosclerosis • BMC Medical Imaging • Clinical Neurology and Neurosurgery • Clinical Neurophysiology • Journal of Child Neurology • Journal of Neurology • Journal of the Peripheral Nervous System

54

• Journal of Postgraduate Medicine • PLoS One • Muscle and Nerve

INSTITUTIONAL SERVICE:

1999-2002 Academic tutor for first and second year medical students 2000-2002 Student Identification and Recruitment Committee 2001-2008 AOA Executive Committee 2004-2005 Graduate Medical Education Committee 2005-2006 Chief Resident Committee

2008-2009 Dean’s Advisory Committee 2005-Present Neurology Residency Advisory Committee 2006-Present Medical School Admissions Interviewer 2006-Present Standardized Patient Assessment evaluator for medical students 2007-Present Core Mentoring Faculty Member for medical students 2007-Present WFUHS Translational Science Institute member 2009-Present WFUHS Center for Worker Health member 2009-Present WFUHS Intramural Research Support Committee ad hoc member 2009-Present WFU Neuroscience Faculty Member 2010-Present Translation Science Institute Scholar 2010-Present WFU Admissions and Premedical Relations Committee Member 2011-Present WFU Faculty Development Advisory Committee 2011-Present P&T Subcommittee – Standardized Order Sets

PROFESSIONAL MEMBERSHIP AND SERVICE:

2004-Present American Academy of Neurology (AAN), Member

55

2004-Present American Association of Neuromuscular and Electrodiagnostic Medicine (AANEM), Member

2006-Present Huntington Study Group (HSG), Junior Investigator 2009-Present The Neuropathy Association, Member 2009-Present Western North Carolina Society for Neuroscience (WNCSN),

Executive Committee Clinical Councilor 2009-Present AANEM Neuromuscular Ultrasound Task Force 2010-Present AANEM Marketing Committee

HONORS AND AWARDS: Research

• 2009 AANEM President’s Research Initiative Award • 2002 G. Milton Shy AAN Clinical Research Award • 2002 Outstanding Scholarly Project Poster Teaching • Wake Forest Class of 2004 Resident Teaching Award

Scholarship • 2011 Best Doctors • 2011 Leading Physicians of the World • 2009 ABEM Top 10% Score on Certification Examination • 2007 ANA Junior Faculty Development Course Scholarship • 2002 WFSM Medical Alumni Association Excellence Award • 2002 WFSM Excellence in Neurology Student Award • 2002 AAN Annual Meeting Scholarship Recipient • 2001 Alpha Omega Alpha • 2000 WFSM Dewitt Cromer Cordell Scholarship • 1998 Phi Beta Kappa • 1996 WFU Carswell Scholarship • Dean’s List 1994-1998

PROFESSIONAL INTERESTS:

• Neuromuscular ultrasound • Polyneuropathy • Amyotrophic lateral sclerosis • Myasthenia gravis

56

Current Research

1. Cartwright MS, Chloros G, Wiesler ER, Walker FO. Nerve ultrasound in carpal tunnel syndrome: a review of the literature.

2. Milligan CE, Cartwright MS, Oppenheim R, Delbono O, Caress JB. Early

changes in the spinal cord and neuromuscular junction with ALS.

3. Strowd R, Cartwright MS, Kapoor S, Siddiqui M. Intracranial hemorrhage following DBS.

4. Mohen S, Cartwright MS, Siddiqui M. Musculoskeletal complaints in

Parkinson’s Disease.

5. Cartwright MS, Reynolds PS, Lefkowitz D, Wilmshurst P, Nightingale S, Bettermann K, Argoff P. Migraine and right-to-left shunts: An AAN Clinical Guideline.

GRANTS: Active

2006-present NIH/NINDS RO1 NS049640-01 (Cudkowicz) A Clinical Trial of Ceftriaxone in Subjects with Amyotrophic Lateral Sclerosis Role: Co-investigator (enroll patients) PI: Cudkowicz

2007-present ALS Association Electrical Impedance Myography in ALS Role: Co-investigator (perform studies) PI: Rutkove

2008-present NIOSH R01OH009251 Work-relate Injuries in Migrant Poultry Workers Role: Co-investigator (5% effort, perform diagnostic studies) PI: S Quandt

2008-present ALS Association

ALS Biomarker Study Role: Co-investigator (enroll patients) PI: Cudkowicz

57

2008-present NIH R21NS061084-01

CSF Indicators for Diagnosis and Disease Progression in ALS Role: Co-investigator (enroll patients)

PI: Milligan $275,000

2008-Present NINDS/NIH

1K23NS062892 Diagnostic Ultrasound for Focal Neuropathies Role: Principal Investigator (75% effort) $690,287

Completed

2006-2008 William E. Winter Clinical Research Training Fellowship Muscular Dystrophy Association Role: Principal Investigator (100% effort) $180,000

2007-2009 Translational Team Science Grant WFSM Translational Science Institute Amniotic Fluid Derived Stem Cell Therapy in a Canine Model of Duchenne Muscular Dystrophy Role: Co-investigator (performed studies) PI: MK Childers $125,000

2008-2010 Translational Team Science Grant WFSM Translational Science Institute Detection of Early Nervous System Changes in ALS Role: Co-investigator (enrolled patients, performed studies) PI: CE Milligan $125,000

2008-2010 NIH/NINDS

A clinical trial of lithium and riluzole in ALS Role: Co-investigator (enrolled patients) PI: Aggarwal

58

BIBLIOGRAPHY:

Peer Reviewed Journals (* indicates the article was the focus of an editorial)

1. Caress JB, Becker CE, Cartwright MS, and Walker FO. Ultrasound in the diagnosis of ulnar neuropathy at the elbow. J Clin Neuromuscular Dis 2003;4:161-162.

2. * Caress JB, Cartwright MS, Donofrio PD, Peacock JE Jr. The clinical

features of 16 cases of stroke associated with administration of IVIG. Neurology 2003;60:1822-1824.

3. Cartwright MS, Jeffery DR, Nuss GR, Donofrio PD. Statin associated

exacerbation of myasthenia gravis. Neurology 2004;63:2188.

4. Walker FO, Cartwright MS, Wiesler ER, Caress JB. Ultrasound of nerve and muscle. Clin Neurophys 2004;115:495-507.

5. Cartwright MS, Donofrio PD, Ybema KD, Walker FO. Detection of a

brachial artery pseudoaneurysm using ultrasonography and EMG. Neurology 2005;65:649.

6. Gordon E, Cartwright M, Avasarala J. Neurocysticercosis causing obstruction

of CSF flow. Arch Neurol 2005:62:1018.

7. Cartwright MS, Reynolds PS. Intracerebral hemorrhage associated with over-the-counter inhaled epinephrine. Cerebrovasc Dis 2005;19:415-6.

8. Cartwright MS, McCarthy SC, Roach ES. Hemimegalencephaly and tuberous

sclerosis complex. Neurology 2005;64:1634.

9. Cartwright MS, Reynolds PS, Rodriguez ZM, Breyer WA, Cruz JM. Lumbar puncture experience among medical school graduates: the need for formal procedural skills training. Med Educ 2005;39:436-437.

10. Cartwright MS, Hickling WH, Roach ES. Ischemic stroke in an adolescent

with arterial tortuosity syndrome. Neurology 2006;67:360-1. 11. Wiesler ER, Chloros GD, Cartwright MS, Smith BP, Rushing J, Walker FO.

The use of diagnostic ultrasound in carpal tunnel syndrome. J Hand Surg [Am] 2006;31:726-32.

12. Wiesler ER, Chloros GD, Cartwright MS, Shin HW, Walker FO. Ultrasound

in the diagnosis of ulnar neuropathy at the cubital tunnel. J Hand Surg [Am] 2006;31:1088-93.

59

13. Cartwright MS, Moore PS, Donofrio PD, Iskandar SS, Stratta RJ. Acute sensory neuropathy associated with rabbit anti-thymocyte globulin. Am J Transplant 2007;7:484-6.

14. Cartwright MS, Shin HW, Passmore LV, Walker FO. Ultrasonographic

findings of the normal ulnar nerve in adults. Arch Phys Med Rehabil 2007;88:394-6.

15. Jen JC, Klein A, Boltshauser E, Cartwright MS, Mamsa H, Baloh RW.

Prolonged hemiplegic episodes in children due to mutations in ATP1A2. J Neurol Neurosurg Psychiatry 2007;78:523-6.

16. Cartwright MS, Walker FO, Chloros GD, Wiesler ER, Campbell WW.

Diagnostic ultrasound for nerve transection. Muscle & Nerve 2007;35:796-9.

17. Cartwright MS, Jeffery DR, Lewis ZT, Koty PP, Stewart WT, Molnar I. Mitoxantrone for multiple sclerosis causing acute lymphoblastic leukemia. Neurology 2007;68:1630-1.

18. Yoon JS, Kim B, Kim SJ, Kim JM, Sim KH, Hong SJ, Walker FO, Cartwright

MS. Ultrasonographic measurements in cubital tunnel syndrome. Muscle & Nerve 2007;36:853-5.

19. Ginn SD, Cartwright MS, Chloros GD, Walker FO, Yoon JS, Wiesler ER.

Ultrasound in the diagnosis of a median neuropathy in the forearm. J Brachial Plex Periph Nerve Inj 2007;2:23.

20. Yoon JS, Kim BJ, Kim SJ, Kim JM, Hong SJ, Walker FO, Cartwright MS.

Ulnar nerve and cubital tunnel ultrasound in ulnar neuropathy at the elbow. Arch Phys Med Rehabil 2008;89(5):887-9.

21. * Cartwright MS, Passmore LV, Yoon JS, Brown ME, Caress JB, Walker FO.

Cross-sectional area reference values for nerve ultrasonography. Muscle & Nerve 2008;37(5):566-71.

22. Cartwright MS, Shin HW, Passmore LV, Walker FO. Ultrasonographic

reference values for assessing the normal median nerve in adults. J Neuroimaging 2009;19:47-51.

23. Yoon JS, Walker FO, Cartwright MS. Ultrasonographic swelling ratio in the

diagnosis of ulnar neuropathy at the elbow. Muscle & Nerve 2008;38:1231-5.

24. Cartwright MS, White D, Miller LM, Roach ES. Recurrent stroke in a child with incontinentia pigmenti. J Chil Neurol 2009;24:603-605.

60

25. Caress JB, Hobson-Webb LD, Passmore LV, Finkbiner A, Cartwright MS. Case-control study of thromboembolic events associated with IV immunoglobulin. J Neurol 2009;256:339-342.


Diagnostic nerve ultrasound in Charcot-Marie Tooth Type 1B. Muscle & Nerve 2009;40:98-102.

27. Chipman JN, Mott RT, Stanton CA, Cartwright MS. The Ultrasonographic

Tinel’s Sign. Muscle & Nerve 2009;40:1033-5.

28. White D, Rees CJ, Butler S, Cartwright MS. Positional dysphagia in Chiari malformation. ENT Journal 2010;89:318-9.

29. Yoon JS, Walker FO, Cartwright MS. Ulnar Neuropathy with Normal

Electrodiagnosis and Abnormal Nerve Ultrasound. Arch PM&R 2010; 91:318-20.

30. Kieburtz K, McDermott MP, Voss TS, The Dimebon in Subjects With

Huntington Disease (DIMOND) Investigators of the Huntington Study Group (Cartwright MS). A Randomized, Placebo-Controlled Trial of Latrepirdine in Huntington Disease. Arch Neurol 2010;67:154-160.

31. Strowd RE, Cartwright MS, Passmore LV, Ellis TL, Tatter SB, Siddiqui MS.

Weight change following deep brain stimulation for movement disorders. J Neurol 2010;257:1293-7.

32. Aggarwal SP, Zinman L, Simpson E, et al., the Northeast and Canadian

Amyotrophic Lateral Sclerosis consortia (Cartwright MS). Safety and efficacy of lithium in combination with riluzole for treatment of amyotrophic lateral sclerosis: a randomised, double-blind, placebo-controlled trial. Lancet Neurol 2010;9:481-8.

33. Strowd RE, Cartwright MS, Okun MS, Haq I, Siddiqui MS. Pseudobulbar

Affect: Prevalence and Quality of Life Impact in Movement Disorders. J Neurol 2010;257:1382-7.

34. * Cartwright MS, White DL, DeMar S, Wiesler ER, Sarlikiotis T, Chloros

GD, Yoon JS, Won SJ, Molnar JA, DeFranzo AJ, Walker FO. Median nerve changes following steroid injection for carpal tunnel syndrome. Muscle & Nerve 2011;44:25-9.

35. Cartwright MS, Yoon JS, Lee KH, Deal N, Walker FO. Diagnostic ultrasound for traumatic radial neuropathy. Am J Phy Med Rehabil 2010; in press.

61

36. Cartwright MS, Walker FO, Griffn LP, Caress JB. Peripheral nerve and muscle ultrasound in amyotrophic lateral sclerosis. Muscle & Nerve 2011: in press.

37. Chahal PS, Sohail W, Cartwright MS. Neuromuscular Ultrasound in the Diagnosis of Focal Neuropathies Superimposed on Polyneuropathy: A Case Report. Clin Neurophysiol 2011: in press.

38. Cartwright MS, Walker FO, Blocker JN, Schulz MR, Arcury TA, Grzywacz JG, Mora D, Chen H, Marín AJ, Quandt SA. The Prevalence of Carpal Tunnel Syndrome in Latino Poultry Processing Workers and Other Latino Manual Workers. J Occup Environ Med 2012: in press.

39. Mayans D, Cartwright MS, Walker FO. Neuromuscular ultrasonography: Quantifying muscle and nerve measurements. Phys Med Rehabil Clin N Am 2012; 23:133-48.

Non-peer Reviewed Manuscripts 1. Chloros GD, Cartwright MS, Walker FO, Wiesler ER. Sonography and

electrodiagnosis in carpal tunnel syndrome, an analysis of the literature. Eur J Radiol 2009;71:141-3.

2. Walker FO, Alter KE, Boon AJ, Cartwright MS, Flores VH, Hobson-Webb

LD, Hunt CH, Primack SJ, Shook SJ. Qualifications for Practitioners of Neuromuscular Ultrasound: A Position Statement of the AANEM Ultrasound Task Force. Muscle & Nerve 2010;42:442-443.

3. Norbury JW, Cartwright MS, Walker FO, et al. Ultrasonographic Evaluation

of Entrapment Neuropathies in the Upper Limb. Practical Neurology 2011;10:38-44

4. Walker FO, Cartwright MS. Neuromuscular ultrasound: emerging from the

twilight. Muscle & Nerve 2011: in press Books and Chapters 1. Neuromuscular Ultrasound. 1st Edition. Eds. FO Walker and MS Cartwright.

Podcasts 1. Neuromuscular ultrasound: part I. Neurology 2010 2. Neuromuscular ultrasound: part II. Neurology 2010

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Abstracts

1. Cartwright MS, Wiesler ER, Caress JB, Donofrio PD, and Walker FO. High-resolution ultrasound in the evaluation of carpal tunnel syndrome. Neurology 2002;58 Suppl 3:A67.

2. Cartwright MS, Reynolds PS, Rodriguez ZM, Breyer WA, and Cruz JM.

Lumbar puncture experience among medical school graduates. Neurology 2004;62 Suppl 5:A77.

3. Cartwright MS, Shin HW, Walker FO. Detailed ultrasonographic

characteristics of the normal median nerve in adults. Neurology 2006;66 Suppl 2:A83.

4. Cartwright MS, Chloros GD, Walker FO, Wiesler ER, Campbell WW.

Diagnostic ultrasound for nerve transaction. Ann Neurol 2006;60:636. 5. Cartwright MS, Chloros GD, Walker FO, Wiesler ER, Campbell WW.

Diagnostic ultrasound for nerve transaction. Neurology 2007;68:Suppl 1:A67. 6. Brown M, Cartwright MS, Caress JB. Diagnostic ultrasound in HMSN1B.

Neurology 2007;68:Suppl 1:A67. 7. Caress JB, Hobson-Webb L, Passmore L, Cartwright MS. A case control

study of thrombo-embolic events associated with IVIg administration. Neurology 2007;68:Suppl 1:A395.

8. Milligan CE, Oppenheim RW, Delbono O, Caress JB, Cartwright MS and the

WFUSM ALS Research Group. Early changes in motoneurons and neuromuscular junctions in the mutant SOD1 mouse model of ALS. 2008 Sporadic Neurodegeneration Program, pg. 67.

9. Milligan CE, Oppenheim RW, Delbono O, Caress JB, Cartwright MS and the

WFUSM ALS Research Group. Early changes in motoneurons and neuromuscular junctions in ALS. 2008 International Symposium on ALS.

10. Yoon JS, Walker FO, Cartwright MS. Ultrasonographic diagnostic value of

area ratio in ulnar neuropathy at the elbow. AANEM 2008 pg 127.

11. Yoon JS, Walker FO, Cartwright MS. Ultrasonography in four cases of ulnar neuropathy with negative conduction studies. AANEM 2008 pg 128.

12. Vishwajit S, Patel B, Herco M, Siddiqui M, Cartwright MS, Badlani G. The

incidence of voiding difficulty and constipation in patients with essential tremor and Parkinson’s disease. Neurourol Urodyn 2009;28:157-158.

63

13. Vishwajit S, Patel B, Herco M, Siddiqui M, Cartwright MS, Badlani G. The effect of deep brain stimulation on voiding dysfunction in Parkinson’s disease and essential tremor. Neurourol Urodyn 2009;28:140-141.

14. Yoshikawa M, Vinsant S, Mansfield C, Moreno RJ, Gifondorwa D, Pace L,

Messi LM, Leles B, Caress JB, Cartwright MS, Delbono O, Oppenheim R, and Milligan C. Identification of Changes in Muscle, Neuromuscular Junctions and Spinal Cord at Early Pre-symptomatic Stages in the Mutant SOD1 Mouse Model of ALS May Provide Novel Insight for Diagnosis and Treatment Development. Society for Neuroscience 2009.

15. Cartwright MS, Walker FO, Caress JB. Ultrasound in the Diagnosis of ALS.

AANEM 2009.

16. Cartwright MS, White DL,Yoon JS, Sarlikiotis T, Chloros GD, Wiesler ER, DeFranzo AJ, Molnar JA, Walker FO. Median nerve changes following steroid injection for carpal tunnel syndrome. AANEM 2009. President’s Initiative Award.

17. Cartwright MS, Walker FO, Caress JB. Ultrasound in the Diagnosis of ALS.

NEALS 2009.

18. Cartwright MS, Walker FO, Arcury TA, Blocker JN, Schulz MR, Quandt SA. Muscle intrusion into the tunnel in carpal tunnel syndrome. Muscle & Nerve 2010;42:630

19. Chukwueke UN, Cartwright MS, Griffin LP, Strowd R, Haq I, Ellis TL,

Abbott V, Herco M, Tatter SB, Siddiqui MS. Unilateral versus bilateral subthalamic stimulation in parkinson’s disease. Movement Disorders. 2011.

PRESENTATIONS:

International, National, and State-wide Presentations (* indicates symposium coordinator)

1. Neuromuscular ultrasound lecturer at the post-meeting symposium. American

Association of Neuromuscular and Electrodiagnostic Medicine Annual Meeting, October 2006, Washington DC.

2. Diagnostic ultrasound for nerve transection. Grand rounds lecture at

Vanderbilt University School of Medicine, October 2007, Nashville, TN.

3. * Neuromuscular ultrasound special interest group (SIG). SIG Coordinator at the American Association of Neuromuscular and Electrodiagnostic Medicine Annual Meeting, October 2007, Phoenix, AZ.

64


Association of Neuromuscular and Electrodiagnostic Medicine Annual Meeting, October 2007, Phoenix, AZ.

5. * Advances in neuromuscular ultrasound symposium. Symposium

Coordinator at the American Association of Neuromuscular and Electrodiagnostic Medicine Annual Meeting, September 2008, Providence, RI.


Association of Neuromuscular and Electrodiagnostic Medicine Annual Meeting, September 2008, Providence, RI.

7. Medical Management of ALS. Keri B. Still Conference on ALS, November

2008, Winston-Salem, NC.

8. * Advances in neuromuscular ultrasound symposium. Symposium Coordinator at the American Association of Neuromuscular and Electrodiagnostic Medicine Annual Meeting, October 2009, San Diego, CA.


Association of Neuromuscular and Electrodiagnostic Medicine Annual Meeting, October 2009, San Diego, CA.

10. Amyotrophic lateral sclerosis. Presentation at the 29th Annual Mountain

Medical Meeting, October 2009, Asheville, NC.

11. Evaluation of neuropathy. Presentation at the 29th Annual Mountain Medical Meeting, October 2009, Asheville, NC.

12. Assessment of Focal Neuropathy with Ultrasound. American Society of

Neuroimaging. January 2010, San Francisco, CA.

13. Evaluation of Peripheral Neuropathy. Presentation at the WFUSM Geriatrics Symposium. February 2010, Winston-Salem, NC.

14. Neuromuscular Ultrasound. Presentation at the North Carolina Neurological

Society Annual Meeting. February 2010, Charlotte, NC.

15. Assessing movement in focal nerve disease. Presentation at the American Association of Neuromuscular and Electrodiagnostic Medicine Annual Meeting, September 2011, San Francisco, CA.

16. Neuromuscular Ultrasound. 6th Annual AHEC Neuroscience Lecture Series,

November 2011, Winston-Salem, NC.

65

International, National, and State-wide Hands-on Workshops 1. Neuromuscular ultrasound instructor at the post-meeting symposium

workshop. American Association of Neuromuscular and Electrodiagnostic Medicine Annual Meeting, October 2004, Savannah, GA.

2. Neuromuscular ultrasound instructor at the post-meeting symposium

workshop. American Association of Neuromuscular and Electrodiagnostic Medicine Annual Meeting, October 2005, Monterey, CA.


workshop. American Association of Neuromuscular and Electrodiagnostic Medicine Annual Meeting, October 2006, Washington DC.


workshop. American Association of Neuromuscular and Electrodiagnostic Medicine Annual Meeting, October 2007, Phoenix, AZ.

5. Neuromuscular ultrasound workshop. Course instructor at the American

Association of Neuromuscular and Electrodiagnostic Medicine Annual Meeting, September 2008, Providence RI.


workshop. American Association of Neuromuscular and Electrodiagnostic Medicine Annual Meeting, September 2008, Providence, RI.

7. Neuromuscular ultrasound workshop. Course instructor at the American

Association of Neuromuscular and Electrodiagnostic Medicine Annual Meeting, October 2009, San Diego, CA.


workshop. American Association of Neuromuscular and Electrodiagnostic Medicine Annual Meeting, October 2009, San Diego, CA.

9. Assessment of Focal Neuropathy with Ultrasound Workshop. American

Society of Neuroimaging. January 2010, San Francisco, CA.

10. Neuromuscular Ultrasound Workshop. Presentation at the North Carolina Neurological Society Annual Meeting. February 2010, Charlotte, NC.

11. Neuromuscular ultrasound for EMG technicians workshop. American

Association of Neuromuscular and Electrodiagnostic Medicine Annual Meeting, September 2011, San Francisco, CA.

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12. Advanced neuromuscular ultrasound workshop. American Association of Neuromuscular and Electrodiagnostic Medicine Annual Meeting, September 2011, San Francisco, CA.

International, National, and State-wide Poster Presentations

1. High-resolution ultrasound in the evaluation of carpal tunnel syndrome.

Poster at the American Academy of Neurology Annual Meeting, April 2002, Denver, CO.

2. Experiences with high-resolution ultrasound in the evaluation of carpal tunnel

syndrome. G. Milton Shy Essay Award poster at the American Academy of Neurology Annual Meeting, April 2002, Denver, CO.

3. Lumbar puncture experience among medical school graduates. Poster at the

American Academy of Neurology Annual Meeting, April 2004, San Francisco, CA.

4. Ultrasonographic characteristics of the normal median nerve. Poster at the

American Academy of Neurology Annual Meeting, April 2006, San Diego, CA.

5. Diagnostic ultrasound for nerve transection. Poster at the American

Neurological Association Annual Meeting, October 2006, Chicago. 6. Diagnostic ultrasound for nerve transection. Poster at the American Academy

of Neurology Annual Meeting, May 2007, Boston, MA. 7. Neuromuscular ultrasound workshop. Course instructor at the American

Association of Neuromuscular and Electrodiagnostic Medicine Annual Meeting, October 2007, Phoenix, AZ.

8. Neuromuscular ultrasound in the diagnosis of ALS. Poster presentation at the

American Association of Neuromuscular and Electrodiagnostic Medicine Annual Meeting, October 2009, San Diego, CA.

9. Median nerve changes following steroid injection for carpal tunnel syndrome.

Poster presentation at the American Association of Neuromuscular and Electrodiagnostic Medicine Annual Meeting, October 2009, San Diego, CA.

Institutional (Wake Forest School of Medicine) 1. Neuromuscular Ultrasonography Course: Coding and Billing – Center for

Medical Ultrasound, October 2005, January 2006, December 2006, March 2007, November 2007, May 2008, November 2008, March 2009, May 2010, March 2011.

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2. Neuromuscular Ultrasonography Course: Peripheral Nerve Appearance –

Center for Medical Ultrasound, October 2005, January 2006, December 2006, March 2007, November 2007, May 2008, November 2008, March 2009, May 2010, March 2011.

3. Evaluation of the unresponsive patient – Internal Medicine, Emergency

Lecture Series, September 2005. 4. Status epilepticus – Internal Medicine, Emergency Lecture Series, August

2005. 5. How to be a good rotating intern – Class of 2005 Phase 5 Lecture, May 2005. 6. Interpreting Nerve Conduction Studies and EMG – Internal Medicine Grand

Rounds, February 2006.

7. Neuromuscular Diseases – Family Medicine lecture series, September 2006, December 2008.

8. Neuromuscular Diseases – Internal Medicine lecture series, February 2007,

October 2007. 9. Evaluation of CSF – Neurology Update for Primary Care Providers, March

2007.

10. Common Neuropathies – Family Medicine lecture series, November 2007

11. Diabetic Neuropathy – Endocrinology lecture series, January 2008, May 2010, March 2011

12. Neuromuscular Ultrasound – SIGN meeting, January 2008

13. Meningitis and Encephalitis – Neurology Update for Primary Care Providers,

May 2008

14. Neurology for the Internal Medicine Board Examination – Internal Medicine lecture series, June 2008

15. Myasthenia Gravis – CT Surgery Grand Rounds, May 2009

16. Neuromuscular Emergencies – Critical Care Grand Rounds, July 2009

17. Introduction to Neurology – First Year Medical Students, August 2010,

August 2011

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18. The Brachial Plexus – First Year Medical Students, October 2010, October 2011

19. Utrasonographic Assessment of Carpal Tunnel Syndrome – Neuroscience

lecture series, April 2011

20. The Neurologic Examination – Organized and taught Phase 5 course, March 2011

21. Carpal Tunnel Syndrome in Poultry Workers – Workers Health Seminar,

April 2011 22. Neuromuscular Ultrasound – Medical Imaging Graduate Course, VT-Wake

Forest School of Biomedical Engineering, May 2011 23. HIV Neuropathies – HIV section meeting, May 2011 24. Guillain-Barre Syndrome – Hospitalists section meeting, May 2011 25. Neuromuscular Ultrasound in Sports Medicine – Sports Medicine Conference,

Family Medicine, June 2011

Departmental (Wake Forest School of Medicine, Department of Neurology)

1. ICH with over-the-counter inhaled epinephrine. Grand Rounds, November 2003.

2. Establishing the diagnosis of myasthenia gravis – EMG Conference,

November 2004. 3. Mimics of Guillain-Barre Syndrome – EMG Conference, October 2004. 4. Primary CNS tumors in the pediatric patient – Pediatric Conference,

September 2004. 5. General pediatrics for the neurologist – Pediatric Conference, August 2004. 6. Statin associated exacerbation of myasthenia gravis – Grand Rounds, March

2004. 7. Neuromuscular ultrasonography – Grand Rounds, February 2005. 8. Atrial septal defects and migraine headaches – Grand Rounds, November

2005.

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9. Neuromuscular diseases – Monthly lecture for medical students, July 2006 - Present.

10. Traumatic nerve injury – Grand Rounds, March 2007.

11. ALS Mimics – EMG Conference, October 2007.

12. Immunosuppression in Neuromuscular Diseases – EMG Conference,

November 2007.

13. Evaluation of Stupor and Coma – Emergency lecture series, July 2007, July 2008, July 2009

14. Post-polio syndrome – EMG Conference, February 2008.

15. Evaluation of pure cerebellar ataxia – EMG Conference, April 2008

16. Introduction to EMG – Emergency lecture series, July 2009

17. Steroid injection for carpal tunnel syndrome – Rehab Fellows Conference,

May 2010

18. Carpal Tunnel Syndrome in Poultry Workers – Neurology Grand Rounds, February 2011

FELLOWS TRAINED

1. 2008-2009: Kara Eickman, MD; Joseph Chipman, MD

2. 2009-2010: B. Lee Kennedy, MD; Kashyap Patel, MD

3. 2010-2011: Chaman Preet Chahal, MD; Waqas Sohail, MD

neuromuscular ultrasound for the evaluation of … · could detect changes in peripheral nerves and...

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