気脳ルーレット断層撮影法—特に聴神経腫瘍診断への応用

PNEUMOENCEPHALO-ROULETTE TOMOGRAM OF ACOUSTIC NEURINOMA

I．はじめに

　聴神経腫瘍は，ある程度症状の揃つた症例では容易に診断し得るが，早期例において，非腫瘍性疾患と鑑別し，腫瘍の拡がり，大きさを診断することは意外に困難なことが多い。最近われわれは，そのような場合に，気脳写をroulette tomographyすなわち転跡織移動方式断層撮影法^11）12）によつて行なえば非常に有用なことを見出した（以下Pneumoencephalo-roulette tomography：PE-rou—lette tomo．気脳ルーレット断層と仮称）。そこで対照例および聴神経腫瘍例について気脳ルーレット断層撮影法の実際をやや詳細に紹介したい。

Pneumoencephalography was undertaken with the roulette tomography. As the application of the rou-lette tomography, the 3-looped superior epitrochoidal tube shift with the full range X-ray exposure was used. Outlines of considerably fine normal and ab-normal structures of the cerebellopontine angle, the shadow of the trigeminal nerve root, for example, which had been a so-called "blind point" through the hitherto reported diagnostic methods, could be well visualized. This method was found to be of value for early diagnosis, determination of progres-sion and differential diagnosis of the acoustic neu-rinoma.