網膜有髄神経線維に伴った網膜剝離の1例

Rhegmatogenous retinal detachment in a case with myelinated retinal nerve fibers

要約　目的：網膜有髄神経線維に併発した網膜剝離の症例の報告。症例：37歳男性が右眼の飛蚊症で受診した。矯正視力は右0.07，左1.2であり，右眼に－8D，左眼に－12Dの近視があった。右眼には硝子体混濁と後部硝子体剝離があり，眼底には上方の血管アーケードに沿う網膜有髄神経線維の上方に3乳頭径（DD）大の網膜欠損と思われる部位と，その周辺側に2DD大の限局性網膜剝離があった。後部硝子体剝離が完成していると判断し，網膜剝離を囲むようにレーザー光凝固を行った。10日後，網膜剝離が周辺側に進展し胞状網膜剝離になったため硝子体手術を行った。術中所見として網膜欠損と思われる部位の周辺側に網膜硝子体癒着があった。網膜は復位し0.6の最終視力が得られた。結論：本症例での網膜剝離は，以前から網膜欠損と思われる部位があり，網膜硝子体癒着による牽引が有髄神経線維のある部位に加わって発症した可能性がある。

Abstract.　Purpose：To report a case of retinal detachment in an eye with myelinated retinal nerve fibers. Case：A 37-year-old male was referred to us for suspected retinal detachment. His corrected visual acuity was 0.07 right and 1.2 left. The right eye had myopia of －8 diopters and the left had －12 diopters. The right eye showed vitreous opacity, posterior vitreous detachment, myelinated retinal nerve fibers along the superior vascular arcade, retinal defect of 3 disc diameters（DD）across, and retinal detachment of 2DD in size. Laser photocoagulation was applied surrounding the area of retinal detachment. Vitreous surgery had to be performed 10 days later after appearance of bullous retinal detachment. As intraoperative finding, vitreoretinal adhesion was present peripheral to the area of retinal defect. Final visual acuity of 0.6 was obtained after reattachment of the retina. Conclusion：Retinal detachment in the present case appears to be due to congenital retinal defect and to traction by vitreoretinal adhesion at the site of myelinated retinal nerve fibers.