急性期クモ膜下出血における脳血管攣縮の局所脳循環に関する臨床的研究

A REGIONAL CEREBRAL BLOOD FLOM IN PATIENTS WITH ACUTE SUBARACHNOID HEMORRHAGE : WITH SPECIAL REFERENCES TO SPASM

I．はじめに

　1951年，Ecker　＆　Riemenschneider^3）が脳血管写により脳血管攣縮の存在を証明して以来，攣縮が破裂脳動脈瘤患者の予後に重大な影響を及ぼすことが判明し^25），その成因，治療法，手術時期に関して多くの検討がなされてきたが，いまだ結論はでていない。クモ膜下出血における脳循環の研究は，それらの諸問題を解決するうえで重要と考えられ，1966年，Kågströmら^15）が⁸⁵Krclearance法を用いて脳循環を測定したのを初めとして，臨床^{5,7,11,14,16,20,29,33,34,36,37,39）}および実験研究^{4,9,30,31,38，39）}がおこなわれてきたが，今日なお一定の見解を得るに到つていない。

　著者は，急性期のクモ膜下出血例について局所脳循環（rCBF）の立場より，脳血管攣縮を中心に，攣縮の程度，推移および臨床症候との相関を明らかにする目的で検討を加え，若干の知見を得たので報告する。

Measurements of the regional cerebral blood flow (rCBF) were performed 44 times on patients with subarachnoid hemorrhage, using the 133-Xe clear-ance method with aid of the 8 channel detector unit.

The patients consisted of 31 preoperative cases within 3 weeks of the last subarachnoid hemorrhage. The sites of the ruptured aneurysms included 11 anterior communicating arteries, 8 middle cerebral arteries, 7 internal carotid arteries and 3 anterior cerebral arteries. In 2 cases, the aneurysms were not identified with the cerebral angiograms.

The purpose of this study was to investigate the effect of spasm on the rCBF. The subjects were divided into two groups : those with and without spasm. Furthermore, the group with spasm was divided into three subgroups according to the degree of spasm.

The findings obtained were as follows;

The group with spasm showed a statistically sig-nificant decrease in the mean of the rCBF.

The MrCBF was not influenced by the distribu-tion of spasm, however.

In the group without spasm, the MrCBF had a good correlation with the cerebrospinal fluid pres-sure (CSF-P) or the level of consciousness. In the group with spasm, there was no correlation between the MrCBF and the CSF-P or the level of consci-ousness. For example that marked reduction of the MrCBF were seen in some cases with low CSF-P or only slight disturbance of consciousness.

The rCBF was measured 2 or 3 times in 5 cases with spasm. The decrease in MrCBF occured about one week after the incidence of the subarachnoid hemorrhage but MrCBF recovered with the disap-pearance of spasm 2 or 3 weeks after the attack.

There was a poor correlation between spasm and relative flow patterns. The good correlation, how-ever, was found in only one case with the severe spasm at the middle cerebral artery.