ABSTRACT
The diagnosis of obstructive sleep apnea (OSA) is currently based on apneic and hypopneic episodes recorded on polysomnography (PSG). These studies indicate those patients with OSA, but do not give further information on the cause of the obstruction, the best method of cure, nor the likelihood of cure. Many diagnostic studies, including lateral cephalometric x-rays, computed tomography (CT), magnetic resonance imaging (MRI), fluoroscopy, flexible pharyngoscopy, upper airway pressure measurements, and acoustic reflection techniques, have been used in an effort to make diagnoses, direct corrective intervention, and predict outcome for interventions. The perfect diagnostic study would distinguish normal nonsnoring patients from snoring patients from OSA patients, be inexpensive, widely available, and reproducible, indicate the cause of the obstructive episodes, and thus the best intervention, predict the level of success for each intervention, and allow for intraoperative monitoring to optimize results for each intervention. Based on these criteria, the perfect study could be done awake and upright in the examination chair using the tools present in all otolaryngology clinics. This would obviate the need for a sleep laboratory to do asleep studies and the need for special instrumentation. Currently, no single diagnostic study fulfills all of these criteria. Many studies have been performed in a quest for the best diagnostic modality, and the results are presented in the following sections.
