脳膿瘍の診断と治療の問題点

BRAIN ABSCESS, ITS DIAGNOSTIC AND THERAPEUTIC PROBLEMS

I．緒言

　近年ペニシリンその他の抗生物質のいちじるしい発達によつて，肺炎，腹膜炎，髄膜炎等の細菌性疾患による死亡率は驚異的な低下を示しているが，脳膿瘍に関しては安藤ら^2），その他の報告をみてもかならずしも好転していないのが現状である。これはその感染巣が脳実質という特殊な組織構造の中に存在すること，治療に際して生命の予後と同時に神経機能の予後をも考慮しなければならないこと，またその早期診断が困難である等の理由に基づくものと考えられる。ここでわれわれが当科において過去4年間に経験した8例を中心とし，これに文献的考察を加え，天幕上脳膿瘍の診断と治療の問題点について述べてみたい。

In this paper we discussed both diagnostic and therapeutic problems in dealing with the brain abscess, mainly based on our experience at this department during the past 4 years.

Because of the lack of inflammatory signs and symptoms as well as obsequity of primary site of infection, diagnosis of the brain abscess is sometimes extremely difficult. One of the most helpful aid in establishing diagnosis is the examination of the cerebrospinal fluid. In this series, most of the cases showed elevation of protein content and increase of white cell count with predominancy of lymphocytes. An-giography is perhaps the most reliable exami-nation in determinattion of the localization of the supratentorial abscesses. However, in one of the cases, we failed to make diagnosis by carotid angiogram because the lesion was lo-cated in the frontal paraventricular region.

As for treatment, in acute and nancasulated cases, if the intracranial pressure is extremely hige, total excision of the abscess with sur-rounding cerebral tissue can not be avoided. On the other hand, if the abscess is encapsulated, aspiration technique should be employed. The essential part of this mothod is close and long-term observation of the abscess cavity left in the brain. For this purpose, at the time of initial aspiration, we inject 1 to 3 cc of Myodil together with antibiotics and obtain serial pyograms. According to the world literature, although most of neurosurgeons have been using throtrast, we found this nonradioactive contrast media to be quite satisfactory. Not only it has better contrast than Throtrast, it seems this material can stay in the cerebral tissue for longer period of time which is a big advantage for long term follow-up. We found excision of the abscess in the chronic stage is not necessary unless the cavity is multilo-cular or becomes a focus of uncontrollable epi-leptic seizures.