Alessandro Bucci
ENT Department – Senigallia. Italy
Title: Endoscopic evaluation during sleep of airway obstruction in OSAS: an update on recent literature and our personal in experience
Biography
Biography: Alessandro Bucci
Abstract
Obstructive sleep apnea (OSA) is a sleep disorder that involves cessation or significant decrease in airflow in the presence of breathing effort. Airway obstruction in OSA can occur at many levels. Surgical procedures are inherently directed at specific regions of the upper airway. Traditionally, upper airway examination is performed while the patient is awake. Nasofibrolaryngoscopy under induced sleep is a promising alternative for identifying sites of upper airway obstruction in patients with OSA. The purpose of this study was to systematically review the evidence regarding the usefulness of Drug Induced Sleep Endoscopy (DISE) compared with that of traditional awake examination for surgical decision- making in patients with OSAS. This review emphasized the direct impact of DISE compared with that of awake examination on surgical decision-making in OSA patients.
Materials and methods used. DISE has been used as a method of evaluation of the upper airway during pharmacologically induced sleep. During DISE artificial sleep is induced by propofol, and the pharyngeal collapse patterns are visualized using a flexible fiberoptic nasopharyngoscope. A systematic review was performed of studies using DISE to identify obstruction sites and patterns of obstruction in patients with OSA. The level (palate, oropharynx, tongue base, hypopharynx/epiglottis), the direction (antero-posterior, concentric, lateral), and the degree of collapse were scored according to the NOHL classification. Only studies with a primary objective of evaluating the usefulness of DISE for surgical decision-making and the importance of identifying multilevel obstruction were selected. Then a retrospective chart review of OSAS patients who underwent DISE at our Centre for Diagnosis and Treatment of Respiratory Sleep Disorders, as part of their surgical evaluation, were reviewed. We compared the results of clinical and diagnostic evaluation with those of sleep endoscopy. According to others authors we found that palatal obstruction was the most frequently observed site of obstruction, followed by tongue base obstruction, laryngeal obstruction and hypopharyngeal obstruction.
Conclusion. Although consensus has been reached on several aspects of the DISE procedure some topics remain open to future research. DISE is an additional method to reveal obstruction sites that have not been detected in awake patients. DISE is mandatory in the diagnostic work-up of OSA and is a valid addition when surgery is considered. DISE is a dynamic, safe, and easy-to-perform technique that visualizes the anatomical sites of snoring or apnoeas. Anyway, larger detailed analyses are needed to determine the importance of each site and degree of obstruction seen on DISE.