CT现在已成为检查听神经瘤最重要的方法,它能较容易地显示出从内耳道突进桥小脑角的大于1cm的肿瘤,但对1cm以下之肿瘤,即使是新型的CT,经静脉给予造影剂的CT也无能为力,不能扫描出内耳道内的肿瘤。作者经腰穿注入少量空气,使之集结于小脑桥脑角,然后进行CT扫描,称之为空气CT;并用“目标成像法”(target imaging),描出了突进桥小脑角微小之肿瘤和局限于内耳道之肿瘤,此外还可辨别位于桥小脑角的面神经和听神经,可描出肿瘤和神经的关系。方法:受检者取坐位行腰穿,注入5～10ml空气或氧气。注入空气时侧头,患耳稍向上,使 CT is now the most important method for the examination of acoustic neuromas. It can more easily show tumors larger than 1 cm from the inner ear canal into the cerebellopontine angle, but for tumors up to 1 cm in size, the contrast agent is administered intravenously even to new types of CT. The CT is also powerless and cannot scan tumors in the inner ear canal. The authors injected a small amount of air through the lumbar puncture to collect them in the cerebellopontine angle, and then performed a CT scan called air CT; and used “target imaging method” to trace the tiny tumors and limitations of the cranial cerebellopontine angle. In the ear canal tumor, in addition can also be identified in the cerebellopontine angle facial nerve and auditory nerve, can be described tumor and nerve relationships. Methods: The examinee took a lumbar puncture and infused 5 to 10 ml of air or oxygen. When the air is injected sideways, the affected ear is slightly upward, so that