若年者の原発性橋出血

JUVENILE PRIMARY PONTINE HEMORRHAGE

I．はじめに

　若年者の原発性橋出血はまれな疾患であり，急に発症し定型的経過をとる場合は診断も必ずしも難しくはないが，亜急性または慢性で，緩徐進行性，動揺性，反復性などを示す例では神経膠腫や多発性硬化症などとの鑑別が困難となる。

　われわれは，それぞれ10年6カ月間および2年6カ月間に3度急な発症の後緩徐進行性の脳幹症状を反復し，終にCT scanning （以下CT）により反復性橋出血と診断し得た興味ある症例を経験した。これを中心に手術および剖検により原発性橋出血を確認した症例を加え，特に脳幹神経膠腫50例と比較し，その鑑別診断を検討したい。なお，診断および経時的観察手段としてのCTの有用性，病因，治療法についても文献的考察を混えて検討を加えてみたい。

Four cases of primary pontine hemorrhage of the young were reported.

Case 1 was a 5 year old boy who had three episodes of neurological symptoms suggesting brainstem lesion for ten and half years. The slow progression and pontine enlargement showed by PEG were identical with that of pontine glioma and he recieved radiotherapy at first. Finally the diagnosis of recurrent pontine hemorrhage was confirmed by CT-scanning. He recovered well from each episode.

Case 2 was a 16 year old boy who had three episodes of neurological symptoms suggesting brainstem lesion for 2 and half years. The slow progression and prodrome suggested brainstem glioma and radiotherapy was performed at first. In the course the multiple sclerosis was suspected but CT-scanning revealed the recurrent pontine hemorrhage. VAG showed an abnormally enlarged vein transversing the pons. He recovered pretty well from each episode.

Case 3 was a 21 year old boy who had pro-gressive symptoms of brainstem lesion. CSF was xanthochromic and PEG revealed the shadow defect at the floor of the fourth ventricle. Diagnosis of pontine hemorrhage or tumor was made and oper-ation of the transventricular removal of the hematoma was performed at 60th day. The post operative course was uneventful.

Case 4 was a 7 year old girl who died of pontine hemorrhage recurred 5 months after the first episode suggesting small pontine hemorrhage.

The small vascular anomaly is supposed to be the cause of such primary pontine hemorrhage characterized as young, non-hypertensive and re-current type. In these cases differential diagnosis from pontine glioma is sometimes very difficult. Xanthochromic CSF is suggestive, though CSF is watery clear in a half of the cases. CT-scanning is extremely valuable for diagnosis and selection of therapy because it reveals blood clot, calcification, mass effect, focal edema, ventricular dilatation and liquefying process of the hematoma. Interestingly, high density remained in two cases longer than one year.

So-called subependymal hematoma has good indi-cation for operation but prudent consideration must be taken to operate the intra-axial hematoma. Nowadays we lay weight on two cases who recovered well non-operatively from 6 episodes,though efforts must be made for diagnosis of the causative small vascular lesion and its radical treatment.