The procedure, first described in 1991, involves sedating patients and passing a fiberoptic telescope through the nose to identify sites of obstruction in the airway, with the premise that appropriate surgery directed to those areas can improve sleep apnea, Dr. Kezirian said.
Explore This IssueJanuary 2007
Some patients with primarily palatal obstruction are greatly improved after palate surgery and tonsillectomy. But many patients have multiple sites of obstruction, and palate surgery alone is less successful in these patients, he said. DISE is designed to identify which procedures may provide the most benefit for individual patients.
Dr. Kezirian and his colleagues are systematically studying DISE to determine if is a reliable test, whether it provides useful information to direct surgical treatment, and whether DISE findings are associated with surgical outcomes. At the 2006 annual meeting of the American Association of Otolaryngology-Head and Neck Surgery (AAO-HNS), he presented a study of 50 patients without previous sleep apnea surgery, and his results showed that DISE findings were not closely related to those of other evaluation techniques, including the Friedman Stage, awake fiberoscopic endoscopy with Müller maneuver, and the lateral cephalogram.
This study was a first step in showing that DISE provides different information compared with other techniques. The next step is to determine whether the information is useful, Dr. Kezirian said. This preliminary work may determine whether DISE should be part of routine surgical evaluation, but instead it may be that the main role for DISE is for patients who do not have ideal results with surgery.
Another active area of research is the use of MRI and CT scans in planning surgery. Different groups around the country are studying whether this will turn out to be useful.
Major Shift in Thinking
One of the most important advances in the field of obstructive sleep apnea is the recognition that it is often a multilevel disease, even in patients with mild sleep apnea, explained Michael Friedman, MD, Professor of Otolaryngology and Chairman of the Section of Head and Neck Surgery at Rush University Medical Center and Chairman of Otolaryngology at Advocate Illinois Masonic Medical Center in Chicago.
New thinking about this disorder is that patients with mild to moderate obstructive sleep apnea can be helped with a multilevel, minimally invasive approach that treats the areas responsible for obstruction. The nose, palate, and tongue base can all be treated with minimally invasive surgery, he said.