head and neck anatomy - acr
TRANSCRIPT
Before You Begin
This module, intended for pre-clinical medical students, is part of the core anatomy teaching series. There should be no prerequisite knowledge necessary for medical students to successfully review and understand this module.
Many of the additional module series in our website build off a strong understanding of human anatomy as it presents in imaging. Please refer back to these anatomy modules if you ever need to review.
If material is repeated from another module, it will be outlined as this text is so that you are aware
Introduction
• The Head and Neck includes:• Skull and Cranial Cavity• Face and Scalp• Eyes and Orbits• Ears• Nasal Cavity and Pterygopalatine Fossa• Oral Cavity and Pharynx• Larynx• Neck
• In this module, we will explore basic H&N anatomy identifiable with common imaging modalities
Head and Neck Radiographs• Utilize ionizing radiation to
capture images
• Material density determines the degree of X-ray attenuation, and thus, appearance:
Gas (Air)
Soft Tissue (Water)
Metal
Fat
Bone
*
Sella
Turcica
Hyoid
Dorsum
sellae Anterior
clinoid
Mastoid
air cells
Palatine
process
of maxilla
Coronal
Suture
*Sag. suture
Frontal sinus
Ethmoid air
cells
Crista galli
Dens
Lesser wing
Greater wing
Mandible
MastoidInf. Turbinate
Frontal
sinus
V
Maxilla
Z
N
Frontal
bone
M
S
P
T
N = nasalV = vomerM= mandibleS = sphenoidP = parietalT = temporal
Clivus
Occipital
condyle
Lamdoidal
suture
Spinosum
Ovale
Jugular foramen
Lacerum
Optic canal
Sphenoid sinus
IAM
Rotundum
H&N CT
• Utilizes ionizing radiation to produce cross-sectional images
• Digital “windowing” can highlight specific tissues
• Note the patient orientation shown to the left
Anterior
Posterior
Right Left
Vertebral
CC
IJV*
Trapezius
Sternohyoid
SCM
Use airway, apices of lung, and
scapula to estimate level on body.
Visceral
compartment
Vascular
compartment
Vertebral
compartment
*
Levator
Scapulae
Semispinalis
Vertebral
CCIJV
Trapezius
Sternohyoid
SCM
Follow Vessels of neck superiorly in axial CT:
CCA, IJV, Vert. art; then follow SCM, then
trapezius
*Common Facial
IJVLevator
Scapulae
Semispinalis
Vertebral
Common Carotid
Trapezius
Sternohyoid
SCM
EJV
@C3/C4
* Hyoid
EJV
IJV
Levator
Scapulae
Semispinalis
Vertebral
External Carotid
SCM
Internal Carotid
Trapezius
Stylomastoid
foramen
*L. Temporalis
L. Lateral
pterygoid
L. Masseter
L. Medial
pterygoid
Maxillary A.
*
IAC
Cochlea
Auricle
EAC
Horizontal (post.)
Semicircular c.
Internal Carotid
Eustachian tube
Vestibule
Malleus
*Lesser wing
Greater wing
Pterygoid hamulus
Ramus of
mandible
Sphenoidal sinus
Medial pterygoid
attachment
SCM
MRI
• Utilizes powerful magnetic fields and radio-frequency pulses to excite (usually hydrogen) atoms within tissues• The energy released by atoms as they return to baseline can be
captured to produce an image
• By varying parameters such as pulse frequency, image qualities can be modulated (i.e. T1 vs T2 weighted)
• MRI can highlight structures that may not be apparent in CT imaging• MRIs are particularly apt when imaging soft tissues
• As they do not rely on X-rays, MRI studies do not expose patients to radiation
Inf. concha
Septum
L. Maxillary sinus
L.Vertebral a.
Nasopharynx
Tens. Veli palatini
m.
R. Medial
pterygoid m.
L. Masseter m.
*Ant. Cer. A.
Ant. Comm. A.
Mid. Cer. A.
Int. Car. A.
Basilar a.
Vertebral a.
Post. Cer. A.
Post. Comm. A.
*Superficial
Temporal a.
Infraorbital a.
Occipital a.
Asc.
Pharyngeal a.
Internal
Carotid a.
External Carotid
a.
Lingual a.
Facial a.
Superior Thyroid. a.
Post. Auricular a.
Maxillary a.
Mid. Meningeal a.
Superior Thyroid
Lingual
Facial Artery
Occipital
Internal Carotid
Maxillary Artery
Superficial Temporal
Middle Meningeal
*
Superior
Thyroid a.
Lingual a.
Facial a.
Occipital a.
Internal Carotid a.
Maxillary a.
Superficial
Temporal a.* Post. Auricular a.