FRIDAY, Feb. 20 (HealthDay News) -- People with the breathing disturbance known as obstructive sleep apnea 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 apnea and 10 patients who were diagnosed as "simple snorers."

Among those with obstructive sleep apnea, 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 percent or more caused by interrupted breathing. These soft palate changes did not occur in the simple snorers.

"Sleep videofluoroscopy quantitatively showed that the soft palate was considerably elongated and angulated in patients with obstructive sleep apnea even in an awake state," wrote Dr. Chul Hee Lee and colleagues in a news release. "It is an easy way to measure the soft palate changes and may be a useful technique to differentiate obstructive sleep apnea from simple snoring with short examination time."

The researchers noted that "identification of the obstruction site of upper airway in patients with obstructive sleep apnea is essential in choosing the appropriate treatment, especially surgical intervention."

The study appears in the February issue of the journal Archives of Otolaryngology -- Head & Neck Surgery.

More information

The U.S. National Heart, Lung, and Blood Institute has more about sleep apnea.