Vol. 18 No 3 Sept. 2001
MEASUREMENT OF THE CROSS-SECTIONAL AREA OF THE PHARYNX USING COMPUTED TOMOGRAPHY IN OBSTRUCTHTE SLEEP APNEA PATIENTS
Ashraf Al-Hamshry MD, Ahmed El-Kady MD, Akram M. Al-Gendy MD, Ahmed Hussien MD, Abu Bakr A. Ras MD and Ahmed Haroon MD
Department of Otorhinolaryngology and Radiology* Benha and Mansoura Faculty of Medicine
The present study was designed to apply computed tomography (CT) scanning for the positional diagnosis of airway obstruction in patients with obstructive sleep apnea (OSA) and to compare the apnea ind ?x (AI) and the square measure of the pharynx obtained before and after uvulo-palatopharyngoplasty (UPPP) and included 25 adult patients complained of snoring and symptoms of OSA. CT imaging of the patients was per¬formed at nasopharynx and oropharynx levels and measurements (saggi-tal and coronal dimensions) were obtained and the cross-sectional area was calculated. At 6 weeks postoperatively, all patients underwent post¬operative CT scanning and the same measurements were obtained at the same level All patients complained of day-time sleepiness and snoring and being mouth breathers night-sleep and. Nine (47.4%) of the male pa¬tients complained of erectile dysfunction. Preoperative apnea index was determined for all patients and was ranging between 13 and 42: mean AI=27.4-9.2. Postoperatively. 14 patients (56%) had improvement in snoring during night sleep with disappearance of mouth breathing. On contrary, only two males reported improvement of their erectile dysfunc¬tion. Subjectively. 16 patients (64%) had Alt 10 while 9 patients (36%) still having AJ>10. Preoperative determination of cross-sectional area using CT showed sensitivity for defining cases with OSA of 90% and accuracy of diagnosis being 92%, and is the most specific data obtained by CT scanning (specificity and PPV=100%). Moreover, there was a negative sig¬nificant correlation between AI and cross-sectional area, (r=-0.749. P<0.001). Postoperative CT scan data showed a significant (P<0.001) in-crease in both dimensions and in the cross-sectional area compared to the preoperative values. It can l>e concluded that CT imaging of the phar¬ynx at the levels of nasopharynx and oropharynx and defining the cross-sectional area coincide with the severity of OSA and could precisely pre¬dict the surgical outcome.