硝子体手術により網膜細動脈瘤を摘出した2例

Excision of retinal arterial macroaneurysm in two cases

　黄斑剝離を併発した巨大な網膜細動脈瘤の2症例に硝子体手術を行い，細動脈瘤を摘出した。第1例は66歳男性で，左眼の乳頭近傍に1.5乳頭径大の網膜細動脈瘤があった。発症3日目の矯正視力は0.7であったが，網膜下出血が黄斑下に拡大し，1週後に視力が0.03に低下した。硝子体手術で意図的網膜裂孔を通じて網膜下出血を除去した。視力は0.5に改善したが，増殖性変化が生じ，黄斑を含む牽引性網膜剝離が起こった。2度目の手術を5週後に行った。増殖膜を剝離・除去し，細動脈瘤を摘出した。最終視力は0.8に回復した。第2例は64歳男性で発症2週後に受診した。左眼に3個の網膜細動脈瘤があった。患眼の矯正視力は1.5であった。2か月後に滲出性網膜剝離が黄斑部に及び，視力が0.2に低下した。発症から約3か月後に硝子体手術を行った。内境界膜を剝離したのち，最も大きな網膜細動脈瘤を摘出し，ほかの2個を光凝固で処理した。最終視力は1.2に回復した。黄斑下血腫や網膜剝離などを伴う網膜細動脈瘤では，黄斑機能を維持・回復させるために，硝子体手術による細動脈瘤切除が有効な選択肢になり得る。

　We successfully excised retinal arterial macroaneurysms by vitreous surgery in two cases. One was a 66-year-old male who had a giant macroaneurysm near the optic disc in his left eye. The visual acuity was 0.7 initially but decreased to 0.03 one week later after the macula was involved by subretinal hematoma. It improved to 0.5 following aspiration of subretinal hemorrhage. A second vitreous surgery had to be performed for tractional retinal detachment 5 weeks later. Proliferative membrane was excised followed by removal of macroaneurysm. The visual acuity improved to 0.8. The other was a 64-year-old male who had 3macroaneurysms in his left eye. The visual acuity decreased from 1.5 to 0.2 after involvement of the macula by exudative retinal detachment. Vitreous surgery was performed 3months after onset. The largest macroaneurysm was excised and the other two were treated by photocoagulation. The visual acuity improved to 1.2. These two cases illustrate that surgical removal of macroaneurysm may be one of beneficial methods to improve visual function.