シリコン製代用硬膜の使用後11年目に後頭蓋窩出血を起こした1症例

Posterior Fossa Hemorrhage 11 Years After the Use of Silastic Dural Substitute: Case report

I．はじめに

　硬膜欠損部の補充や外減圧にさいし，種々の代用硬膜が用いられてきた．シリコン製代用硬膜もその一つで，かつてしばしば用いられたが，術後の出血合併症等の報告があり，最近ではほとんど使用されなくなった．

　今回著者らは，頭部外傷の手術より11年もの後に，後頭蓋窩出血をきたした症例を経験した．開頭の結果，シリコン製代用硬膜が出血の原因とわかり，未だに忘れてはならない合併症と考え報告する。

A case of posterior fossa hemorrhage is reported. The hemorrhage occurred 11 years after posterior fossa craniotomy with closure using a graft of silastic dural substitute.

This 14 year-old girl underwent suboccipital cra-niotomy at the age of 3 years because of traumatic posterior fossa hemorrhage. The dura mater was re-paired with a piece of dural substitute. Eleven years la-ter, she developed severe headache and vomiting. Com-puterized tomography scanning revealed a high density area in the right posterior fossa. At exploration, a fresh clot was evacuated between the dural graft and the fib-rous scar tissue. The resected fibrous scar tissue was 1cm thick, and was adhering to the duro glial scar tis-sue. Her postoperative course was uneventful, and she was discharged 2 weeks after surgery. Microscopic ex-amination of the fibrous scar tissue revealed an outer layer of loose connective tissue with numerous capil-laries. The inner layer consisted of dense connective tissue.

It was speculated that fragile capillaries of fibrous scar tissue caused this hemorrhage. Surgeons should not forget this complication although silastic dural sub-stitute is less used than it used to be.