People with obstructive sleep apnoea have soft palates that are more elongated and angled than those of people without the condition, researchers report.
The soft palate is the tissue at the back of the roof of the mouth. A team at the Seoul National University College of Medicine, in South Korea, used sleep videofluoroscopy - which combines X-ray images with video recording - to evaluate 53 patients with obstructive sleep apnoea and 10 patients who were diagnosed as "simple snorers".
Among those with obstructive sleep apnoea, the length and angle of the soft palate increased while they were awake and when they experienced "desaturation sleep events" - a drop in blood oxygen levels of 4% or more caused by interrupted breathing. These soft palate changes did not occur in the simple snorers.
What the study found
"Sleep videofluoroscopy quantitatively showed that the soft palate was considerably elongated and angulated in patients with obstructive sleep apnoea even in an awake state," wrote Dr Chul Hee Lee and colleagues. "It is an easy way to measure the soft palate changes and may be a useful technique to differentiate obstructive sleep apnoea from simple snoring with short examination time."
The researchers noted that "identification of the obstruction site of upper airway in patients with obstructive sleep apnoea is essential in choosing the appropriate treatment, especially surgical intervention".
The study appears in the journal Archives of Otolaryngology - Head and Neck Surgery.- (HealthDay News, February 2009)