[Delayed intracerebral hemorrhage following VP shunt operation].

Three cases of communicating hydrocephalus after subarachnoid hemorrhage are reported that underwent ventriculoperitoneal shunt and suffered from delayed intracerebral hemorrhage along the ventricular catheter. Ventricular catheters were inserted into the posterior horn with minimal brain damage by our method, in case 1 and 2, 3 times try of ventriculostomy, in case 3, replacement along the same route on the shunt revision. Blood pressure control after the operation was good and bleeding tendency was not observed. Vascular anomaly was not found in preoperative angiography in any case. In case 1, 60 year-old man, intracerebral hemorrhage occurred on the 7th-9th postoperative day as the result of respiratory acidosis and generalized convulsion which needed assisted ventilation for two days. In case 2, 54 year-old man and case 3, 59 year-old woman, headache and hemiparesis suddenly developed immediately after micturition 4 days after operation. Postoperative CT scan revealed that cranioplasty, performed at the same time as shunt operation, caused mass effect on the shunted side of the brain in case 2. In case 3, VP shunt system revised did not seem to function so well. These conditions might predispose the shunted brain to bleed, in addition to the increased intracranial pressure or blood pressure probably produced by Valsalva effect at micturition. These cases indicate that the small surgical wound in the brain induced by shunt procedure could cause progressive degenerative vascular change and bring about delayed intracranial hemorrhage under some predisposing factors.