先天性網膜分離症における硝子体手術の1例

A case of vitrectomy in congenital retinoschisis

　強い硝子体出血を伴った先天性網膜分離症で出血の自然吸収が見られなかったため，硝子体切除を行った症例を報告した．

　耳側に見られた胞状の網膜分離部に内層裂孔が存在し，その部の網膜血管の一部はbridge状となっており，網膜分離部に網膜硝子体癒着が見られることが術中に判明した．硝子体出血がこの部の血管の破綻により生じたものと思われ，硝子体牽引を十分に除去した．しかし術後1年以上を経て再び硝子体出血が生じ，これはすぐに自然吸収された．硝子体牽引は除かれたはずであるから，今回の出血の主因は内層裂孔の形成，あるいは拡大による血管破綻が考えられ，出血を生じたと思われる網膜血管をアルゴンレーザーにより閉塞させ，その後再出血を見ない．

　本症では，硝子体出血や網膜剥離など硝子体手術の適応になりうる合併症が多く見られるにもかかわらず，硝子体手術の報告はほとんどない．硝子体切除中に得た我々の経験を述べた．

A 20-year-old male presented with massive vitreous hemorrhage in his left eye and with X-linked retino-schisis in the fellow eye. We performed vitrectomy for his left eye 9 weeks after the occurrence of hemorrhage.During surgery, we noted a ballooning retinoschisis in the inferior temporal quandrant, where the retinal vessels bridged the tears located on the inner retinal layer. Portbms of the posterior vitreous cortex remained adherent to the vessels, causing traction. The surgery was a success, with the patient recovering the earlier vision.

Vitreous hemorrhage in the same eye recurred 15 months later, followed by rapid reabsorption. Since the traction by the vitreous had been alleviated by prior surgery, the main cause of the vitreous hemorrhage appeared to be due to rupture of a retinal vessel when an inner retinal break enlarged. The suspected vessel was later closed by argon laser.