内耳壓に關する實驗的研究—特にパンピングの内耳壓に及ぼす影響〔大藤教授開講十周年記年論文〕

　1．緒言

　昭和15年，恩師大藤教授^1）は永井と共に從來耳科學的治療の圈外に置かれていた先天性聾唖に對して聽力治療乃至は殘聽増大の目的を以て大量腦脊髓液排除による迷路液誘導法なる一新法を發表した．爾來，本教室に於ては之が實施例を重ねると共に臨床的觀察を進め，その效果を確認した．

　然るに最近之と同樣なる考えに立脚して，先天聾に腦脊髓液パンピングを行うことが執行^2）により發表され（昭和22年），以來各所で實施され同樣な效果を擧げている．

Nomoto investigated the effects of spinal pum-ping, which is employed for the treatment of inner ear deafness, on the pressure of the internal ear. Pressure changes of this area are made visible by the following method: A calibrated capillary tube filled with colored physiological saline solution, as an indicator, is inserted, in the oval window of the rabbit's ear, and made fast by cementing. As the spinal fluid is withdrawn the inner ear pressure will be seen to respond with a definite fall, but as soon as the fluid thus withdrawn is returned to the spinal canal again, the pressure in question regaine its original level. The data on the time of reponse of the inner ear to the rie, and fall of the spinaI fluid pressure which is cau-sen by pumping actions, show a greater delay with the fall. For this reason, that the spinal pumping to be more effective, a short interval of delay should be instituted after each withdrawal in the action of pumping.

The amplitude of pressure changes in the in-ternal ear correspond directly to the volume of spinal fluid displacement.

With adequate removal of spinal fluid the inte-rnal ear pressure is decreased. In this condition the spinal fluid attains its normal state of pressure within the period of 1-2 hours; but, the decreased internal ear pressure usually remain thus, for a considerable period of time, or, it may never to its previous level.