Tonsils and sleep apnea

Pediatrics for Parents, April, 2002

Children who snore, sleep restlessly, and continually complain of being tired may suffer from sleep apnea. The apnea (cessation of breathing) occurs when the child's tonsils are big enough to temporarily close off his airway.

One way to make this diagnosis is with overnight polysomnography, also called a sleep study. This study, which usually takes all night, monitors a number of body functions--heart rate, EKG, breathing patterns, amount of oxygen in the blood, etc.--while the child sleeps. The child's sleep patterns are also monitored by an observer. The results of the study can tell the doctor if the child has sleep apnea.

Since large obstructing tonsils are a frequent cause of obstructive sleep apnea, doctors at the Prince of Wales Hospital in Hong Kong wanted to find a reliable way to determine if a child's tonsils are large enough to cause obstructive sleep apnea.

They found a lateral x-ray of the neck (the x-rays are aimed at one side of the neck and the film is on the other side) is a good way to measure the size of a child's tonsils and pharynx (the air passage). When the ratio of the largest tonsil diameter to pharynx was greater than 0.48, the tonsils were big enough to cause obstructive sleep apnea.

The real benefit of this study is that for the child with suspected obstructive sleep apnea, a simple x-ray is as good as the more complex and expensive sleep study in determining if the child would benefit from a tonsillectomy.

Archives of Diseases in Childhood, 8/02.