糖尿病黄斑浮腫に対する硝子体手術後の視力と光干渉断層計所見の検討

Visual acuity and findings by optical coherence tomography after vitreous surgery for diabetic macular edema

要約　目的：糖尿病黄斑浮腫に対する硝子体手術術後の視力と光干渉断層計（OCT）所見との相関について検討する。対象と方法：糖尿病黄斑浮腫に対して硝子体手術を施行し，術後12か月以上経過観察を行えた症例（38例50眼）を対象とした。術前の黄斑部OCT所見により網膜膨化型，囊胞様変化型，漿液性網膜剝離型に分け，術後視力とOCT所見を検討した。結果：網膜膨化型では術後有意な視力改善を得た。囊胞様変化型と漿液性網膜剝離型ではOCTで術後中心窩網膜厚は有意に減少した。術前および術後12か月において視力は外境界膜（ELM）残存率，視細胞内節外節接合部（IS/OS）残存率と相関を認め，また，術前ELM残存率と術後12か月視力は相関を認めた。結論：視力はELMとIS/OSの残存率と相関を認めた。視力およびOCTでELMとIS/OSが保たれている段階での手術が望ましいと考えられた。

Abstract.　Purpose：To report visual acuity and findings by optical coherence tomography（OCT）after vitreous surgery for diabetic macular edema（DME）. Cases and Method：This retrospective study was made on 50 eyes of 38 patients who received vitreous surgery for DME in the past 3 years. The series comprised 26 male and 24 female eyes. The age averaged 63 years. OCT showed retinal swelling in 17 eyes, cystoid edema in 21 eyes, and serous retinal detachment in 12 eyes. Results：Visual acuity improved significantly in eyes with retinal swelling. Foveal thickness decreased significantly in eyes with cystoid edema or serous detachment. Visual acuity before and 12 months after surgery was positively correlated with residual rate of external limiting membrane and junction line between inner and outer photoreceptor segment. Visual acuity 12 months after surgery was significantly correlated with residual rate of external limiting membrane before surgery. Conclusion：Visual acuity in eyes with DME was correlated with residual rate of external limiting membrane and junction line between inner and outer photoreceptor segment. Vitreous surgery for DME is advocated before decrease of visual acuity, damage to external limiting membrane and impaired junction line between inner and outer photoreceptor segment.