Acute idiopathic blind spot enlargement症候群の経過観察中に僚眼の漿液性網膜剝離を伴った1例

A case of serous retinal detachment in the fellow eye during the course of acute idiopathic blind spot enlargement syndrome

要約　目的：Acute idiopathic blind spot enlargement（AIBSE）症候群の経過観察中に僚眼の漿液性網膜剝離（SRD）を発症した1例を報告する。

症例：円形脱毛症に対してプレドニゾロン5mg内服中の54歳，女性。X−6か月頃より右眼の視野欠損を自覚し前医を受診した。眼底所見は両眼の近視性変化および左眼の黄斑変性を認める程度で，頭部および眼窩MRIでは特記すべき異常はなく，精査加療のためX日に名古屋大学医学部附属病院（当院）に紹介となった。当院初診時の矯正視力は左右ともに1.0で，前眼部および中間透光体に特記すべき異常はなかった。眼底は右眼に傾斜乳頭および下方の網膜神経線維層欠損を認め，左眼では黄斑部近傍に白斑を認めた。光干渉断層計では右眼にellipsoid zoneの途絶および不明瞭化を認め，左眼に網膜色素上皮の小隆起を認めた。フルオレセイン蛍光眼底撮影では右乳頭周囲の蛍光漏出を認め，眼底自発蛍光で同部位の過蛍光を認めた。Goldmann動的量的視野検査では右Mariotte盲点の拡大を認め，多局所網膜電図において同領域に一致した波形減弱がみられた。右眼のAIBSE症候群として経過観察としたところ，X＋1か月に左眼にSRDを生じた。ステロイド関連中心性漿液性脈絡網膜症の可能性を考慮し，プレドニゾロンを休薬とした。X＋2か月にはSRDは消退し現在まで再発はなく，右眼についても所見の悪化は認めていない。

結論：AIBSE症候群における経過中に僚眼のSRDを発症した1例を経験した。患眼の治療マネジメントの選択については十分な検討の必要があると考えられる。

Abstract　Purpose：To report a case of serous retinal detachment（SRD）that developed in the fellow eye during the follow-up of acute idiopathic blind spot enlargement（AIBSE）syndrome.

Case：A 54-year-old woman taking 5 mg of oral prednisolone for alopecia areata. Approximately 6 months prior to presentation, she noticed a visual field defect in the right eye and consulted a previous doctor. Fundus examination revealed myopic changes in both eyes and macular degeneration in the left eye. Head and orbital magnetic resonance imaging showed no significant abnormalities. She was referred to Nagoya University Hospital for a detailed examination and treatment. At the initial examination, corrected visual acuity was 1.0 in both eye, with no significant abnormalities in the anterior segment or media. Fundus examination revealed a tilted disc and inferior retinal nerve fiber layer defect in the right eye, and white patches near the macula in the left eye. Optical coherence tomography showed disruption of the ellipsoid zone in the right eye and a small retinal pigment epithelium elevation in the left eye. Fluorescein angiography revealed fluorescein leakage around the right optic disc, and fundus autofluorescence showed hyper-autofluorescence in the same area. Goldmann kinetic perimetry indicated an enlarged Mariotte blind spot in the right eye, and multifocal electroretinogram demonstrated reduced responses corresponding to the same region. During the follow-up of right eye for AIBSE syndrome, SRD developed in the left eye one month later. Considering the possibility of steroid-associated central serous chorioretinopathy, prednisolone was discontinued. Two months following the initial presentation, the SRD had resolved without recurrence, and no worsening of findings in the right eye was observed to date.

Conclusion：We report a case where SRD developed in the fellow eye during the course of AIBSE syndrome. The management of such cases should be fully considered.