未熟児網膜症の硝子体手術における灌流ポート設置法

Positioning of irrigation port through the corneoscleral limbus in closed vitrectomy for retinopathy of prematurity

　5期未熟児網膜症4例4眼に対して，硝子体手術を行った。生後18週から23週であり，在胎期間は24週から28週であった。長さ2.5mmの灌流ポートを角膜輪部から1.5mm後方に置き，毛様体雛襞部を貫通し，水晶体内に先端を刺入した。まず水晶体切除と水晶体後面の増殖膜処理を行い，網膜の牽引を十分に開放した時点で硝子体内にヒアルロン酸を注入して漏斗状の網膜を伸展させた。術中に医原性裂孔が生じた場合には気圧伸展網膜復位を行った。4眼中1眼に完全復位，2眼に部分復位が得られた。この灌流ポート設置法は，周辺部網膜を損傷する危険が少ないこと，角膜内皮障害が少ないこと，術野が十分に確保できることなどの利点を有し，未熟児網膜症の硝子体手術の一変法として有用であると考えられた。

We performed closed vitrectomy in 4 eyes of 4 babies with stage 5 retinopathy of prematurity. They were aged 18 to 23 weeks at the time of surgery born after 24 to 28 weeks of gestation. A 2.5 mm infusion cannula was inserted 1.5 mm posterior to the corneal scleral limbus so that it perforated the pars plicata of the ciliary body with its tip placed in the lens. We performed lensectomy and removed the retrolental fibrovascular tissue. After release of traction to the retina, viscoelastic material was injected into the vitreous to stretch the funnel-shaped retina. Iatrogenic retinal break was treated pneumatically, The retina was totally reattached in 1 eye and partially in 2. The present method of placing the irrigation port was useful and had the following advantages: lesser risk of damage to the peripheral retina and to the corneal endothelium, and larger surgical field.