慢性硬膜下血腫と頸動脈写—特に血腫のlateralityについて

CEREBRAL ANGIOGRAPHY IN CHRONIC SUBDURAL HEMATOMAS:WITH SPECIAL EMPHASIS ON THE LATERALITY OF HEMATOMA

I．はじめに

　典型的な慢性硬膜下血腫の脳血管写像についてはすでに多数のすぐれた記載があり^{1）〜4）6）8）}，その診断も通常容易である。ただ本症の診断上問題になるのは，第一に血腫がしばしば両側性であること，第二に"慢性硬膜下血腫を見落さない唯一の方法はこの疾患の存在の可能性を常に念頭に止めておくことである"とまでいわれることからも知られるように，本疾患に特有な所見はなく，頭重感あるいは精神症状などまつたく不定の症状のみを訴えて受診する例が多いことである。

　第一の両側性血腫の点について，一般に慢性硬膜下血腫が血管写による前大脳動脈の偏位を伴わない場合には血腫は両側性であり，血腫と同時に前大脳動脈の偏位がある場合には一側性である，といわれているが，われわれの経験からは問題はこのように単純に律し得るものではない。

1) Clinical records of 101 cases of chronic subdural hematoma encountered in the past 10 years in our clinic were reviewed, and 72 technically satisfactory carotid angiograms were re-evaluated. Maximum thi-ckness of the hematoma (P) and maximum shift of the anterior cerebral artery (A) were measured on the A-P views of angiograms and the index,I=A/P×100(%), was calculated according to Nelson and Frei-manis.

2) All but 3 cases were male, and the majority being in the 4 th decade or over.

3) Hematoma was unilateral on the left side in 55~60%, on the right in the 25~30%, and bilateral in the remaning 15%.

4) In no case "A" value exceeded "P" . When "A" was larger than one-half of "P" , the hematoma was almost always unilateral. When "A" was less than 50% of "P" , contralateral hematoma should be excluded with due care. When the chronic subdural hematoma is suspected clinically, no shift and no avascularity in the parietal region are not necessarily incompatible with the hematoma on the opposite side.

5) No correlation was noted between the ages of the patients and "P" or "I" values.

6) Unilateral motor or sensory disturbance proved to be the most reliable lateralizing sign with a high accuracy of ca 95%. Mydriasis, on the other hand, indicated the side contralateral to the hematoma in 30% of the cases.