目的　乳突气房通过气房粘膜可以实现乳突腔的气体交换而不必依赖耳咽管 ,而气房表面积是影响交换速度的重要因素 ,也是研究其生理机能的重要参数。作者通过数字 CT扫描技术进行测量。方法　 15例 ( 2 4只健耳 ) CT扫描厚度 2 mm,共 2 4～ 32层 ,对照片扫描后采用计算机二维重 The purpose of mastoid air room through the mucosa of the air chamber can achieve mastoid gas exchange without having to rely on the eustachian tube, and the air chamber surface area is an important factor affecting the exchange rate, but also an important parameter to study its physiological function. The authors measured by digital CT scanning technique. Methods 15 cases (24 healthy ears) CT scan thickness of 2 mm, a total of 24 to 32 layers of the scan after the use of computer-dimensional two-dimensional