Aveo Tongue Stabilizing Device For Treatment of Obstructive Sleep Apnea

BY

AHMAD YOUNES

Professor of Thoracic MedicineProfessor of Thoracic MedicineMansoura Faculty of MedicineMansoura Faculty of Medicine

Introduction:• Although CPAP provides the most widely used

method to treat sleep disordered breathing today, it is also the most cumbersome one.

• Many patients find it unappealing, difficult to tolerate and unacceptably arise from outside the body .

• The only other non invasive alternative which can produce favorable results within a short time is oral appliance. Hoffstein Sleep Breath 2007; 11: 1-22.

• Oral appliances are a simpler alternative to CPAP for the treatment of OSA as they are quiet, portable and don not require a power source Cistulli et al Sleep Med Rev 2004;8,6:443-457

• oral appliance can be regarded as being either mandibular advancement splint (MAS) or tongue retaing device (TRD).

• MAS generally attach to the dental arches and mechanically protrude the mandible.

• TRD use suction pressure to maintain the tongue in a protruded position during sleep. MAS therefore require the patient to have sufficient teeth whereas TRD can be used by edentulous patients Ferguson et al . Sleep 2006; 29(2): 244-262

• The American Academy of Sleep Medicine recommended the use of oral appliances

for mild to moderate OSA or patients with severe OSA who are unable to tolerate CPAP or refuse treatment with CPAP.

• There is reboust evidence of the efficacy of oral appliances both in regard to improvement of polysomnographic

indices as well as modifying the health risk associated with OSA Ferguson et al .

Sleep 2006; 29(2): 244-262

Aims of this work:

• The aims of this work were to evaluate the efficacy and complications of Aveo-tongue stabilizing device in the treatment of OSA and to determine the predictors of its success.

Subjects and methods: • The inclusion criteria of the cases of this study

were at least two symptoms of OSA (snoring, fragmented sleep, witnessed apneas, morning headache and daytime sleepiness) and evidence of OSA on PSG (AHI 5/hour)

• Exclusion criteria include severe OSA (AHI > 30/hour), bruxism, central apneas, regular use of sedatives, exaggerated gag reflex and standard contraindications for magnetic resonance imaging (MRI) such as cardiac defibrillators and metallic prothesis.

• From twenty patients who commenced the trial, 15 patients completed the study (2 patients refused the device and 3 patients dropped during follow up).

For the remaining fifteen patients, the following were done:

• Thorough history taking with stress on symptoms of OSA.

• Physical examination with stress on neck circumference, body mass index (BMI), and upper airway examination to exclude space occupying lesions in the nose and mouth and dental examination (teeth and gum).

• Full night PSG for objective diagnosis of OSA and repeated later on after 1 month of acclimatization of the patients on the device for assessment of response to appliance. Positional OSA means >50% of AHI occur in supine position .

• Consultation with the Prosthodontic Department, Mansoura Faculty of Dentistry, was done for proper insertion of the TRD device intra-orally.

• The TRD used in this study was a preformed ,non adjustable appliance. Aveo-tongue stabilizing device made by Innovative Health Technology PO Box 17572 Chritchurch, New Zeland.

• Intra-oral examination was made to exclude any local inflammatory causes which prevent placement of the device, so thorough examination was performed and the prosthodontist learned the patients how to insert and remove the device intra-orally and instruct the patient for the way for maintaining the proper oral hygiene measures and hygiene measures of the device.

• Follow up program for all the patients was performed during the period of study every week.

• MRI was done on the upper airways with assessment of the shortest retro-palatal and retro-glossal dimensions (Antero-posterior and lateral) with and without wearing the device while the patients were awake in supine position. A mid saggital slice was done first and from which the shortest retro-palatal and retro-glossal trans-axial slices were chosen for calculation of antero-posterior and lateral dimensions.

• Response to the device (symptoms of OSA especially Epworth sleepiness scale (ESS) and results of PSG while wearing the device were assessed after 1 month of use of the device .

• Complete success means reduction of AHI to a level of normal(< 5 events / hour).

• Partial success means > 50% reduction in AHI but the residual AHI > 5 events / hours.

• Treatment failure means < 50% reduction in AHI Chan et al Chest 2007; 132: 693-699

• Assessment of complications and compliance were done after 1 month of wearing the device.

Results

• This prospective study comprised 15 patients with mild to moderate OSA. The mean age was 36 ± 3.3 years, 60% (9 out of 15) were males and 40% (6 out of 15) were females, the mean BMI was 29.8 ± 1.9 and mean neck circumference was 40.2 ± 2.8 cm.

Table (1): Symptoms of studied cases of OSA without and with use of the oral appliance

Symptoms

without oral appliance

with oral appliance

Statistics

No % No % Z P value

1) Snoring2) Daytime sleepiness3) Morning headache4) Nocturnal choking5) Witnessed apnea

15151198

10010073.360

53.3

56344

33.34020

26.726.7

3.163.0

2.832.242.0

0.002*0.003*0.005*0.025*0.046*

Table (2): ESS of studied cases of OSA without and With use of oral appliance.

  Mean ± SD Statistics

ESS without oral appliance

ESS with oral appliance

13.33 ± 1.29

9.6 ± 1.84

t = 10.84

P < 0.001 *

ESS Epworth sleepiness scale

Table (3): PSG parameters in studied cases of OSA without and with oral appliance.

PSG parametersWithout oral appliance

Mean ± SD

With oral appliance

 Mean ± SDStatistics

(1) De-saturation index (events/hour) 17.6 ± 2.35 14.1 ± 3.5t = 10.09

P < 0.001*

(2) Average duration SaO2 < 90% (second)

23 ± 3.89 18.67 ± 5.77t = 6.96

P < 0.001*

(3) Minimum SaO2 % 81.47 ± 30.4 85.6 ± 4.05t = 6.63

P < 0.001*

(4) % Total sleep time SaO2 < 90% 2.85 ± 0.82 1.89 ± 0.95t = 16.42

P < 0.001*

(5) AHI (events/hour) 23.67 ± 4.03 9.93 ± 6.52t = 15.69

P < 0.001*

(6) Arousal index (events/hour) 31.07 ± 4.06 20.67 ± 4.68t = 13.34

P < 0.001*

(7) % Total sleep time of snoring 15.76 ± 5.99 4.2 ± 4.14t = 10.033P < 0.001*

Table (4): MRI of the upper airways of studied cases of OSA without and with oral appliance

 Without oral appliance

Mean ± SD

With oral appliance

 Mean ± SDStatistics

Retro-palatal      

(a) Antero-posterior dimension (millimeter)

4.53 ± 0.52 6.60 ± 0.51t = 9.025

P < 0.001*

(b) Lateral dimension (mm) 8 ± 0.76 11.1 ± 1.6t = 16.16

P < 0.001*

(c) Antero-posterior / Lateral ratio 0.57 ± 0.10 0.59 ± 0.10t = 7.485P < 0.001

Retro-glossal      

(a) Antero-posterior dimension (mm) 10.5 ± 0.52 13.7 ± 1.03t = 14.4

P < 0.001*

(b) Lateral dimension (mm) 19.7 ± 0.45 23.7 ± 1.5t = 11.8

P < 0.001*

(c) Antero-posterior / Lateral ratio 0.53 ± 0.02 0.58 ± 0.02t = 6.537

P < 0.001*

Table (5): Outcome of aveo-tongue stabilizing device in patients with OSA

  No %

Complete success

Partial success

Treatment failure

6

3

6

40

20

40

Total 15 100

Table (6): predictors of success in studied cases of OSA with oral appliance

 Success (9)Mean ± SD

Failure (6)Mean ± SD

Statistics

Age 35.67 ± 3.39 36.50 ± 3.51t = 0.460P = 0.653

Neck circumference 38.11 ± 1.05 43.33 ± 1.03t = 9.473

P <0.001 *

BMI 29.11 ± 1.36 32.83 ± 2.23t = 3.869

P = 0.002*

ESS 12.78 ± 0.67 14.17 ± 1.60t = 2.347P = 0. 35

Basal SaO2 90.89 ± 0.93 91.17 ± 0.75t = 0.609P = 0.553

% Total sleep time SaO2 < 90% 2.37 ± 0.61 3.57 ± 0.51t = 3.955

P = 0.002*

AHI 20.67 ± 1.73 28.17 ± 0.41t = 12.481P <0.001*

Arousal index 30.89 ± 3.48 31.33 ± 5.16t = 0.200p = 0.844

% Total sleep time snoring 13.82 ± 7.05 18.17 ± 2.07t = 1.942

P = 0.081

Table (7): Effect of positional OSA on outcome of oral appliance

 Predominant Side AHI (8)

Predominant supine AHI (7)

Statistics

Success (9)Failure (6)

2 (25%)6 (75%)

7 (100%)0 (0%)

2 = 8.750P = 0.003

*

Table (8): Compliance of use of aveo tongue stabilizing device in patients with OSA

  No %

Compliant

Non compliant

9

6

60

40

Total 15 100

Table (9): Complications of Aveo tongue stabilizing device in patients with OSA

  No %

Excessive salivation

Oral dryness

Tongue abrasion

Jaw pain

12

10

9

1

80

66.7

60

6 

The limitations of this study include

• The MRI imaging of the upper airway were done for patients during wakfullness which differ from the physiologic state of sleep

• Relatively small number of studied cases • short duration of follow up .

Conclusions

• Aveo TRD was effective in treatment of 60% of mild to moderate OSA and side effects occurred frequently to the extent to prevent 40% of patients to stop use of the device.

• The predictors of success were cases with low BMI, small neck circumference, low AHI and less hypoxemia and predominant supine AHI.