視神経乳頭所見と視野との対応が異なる視神経低形成に併発した開放隅角緑内障の2例

Discrepancies between visual field and disc findings in two cases of optic nerve hypoplasia with open-angle glaucoma

　44歳と72歳女性を両眼の視神経低形成に併発した開放隅角緑内障と診断した。視野と視神経乳頭の対応が異なっていた。症例1では右眼下方視野に同心円状の狭窄，左眼下耳側視野に楔形の欠損と上下のBjerrum暗点があった。Heidelberg Retina Tomograph（HRT）で，Bjerrum暗点に相当する異常が検出されたが，視野の同心円状の狭窄と楔形の欠損に相当する異常は検出されなかった。症例2では両眼の耳側に楔形の視野欠損，右眼上方の視野欠損，左眼上下のBjerrum暗点があった。HRTで，楔形の視野欠損とBjerrum暗点に相当する異常が両眼に検出された。視神経低形成に伴う緑内障では，視野異常と乳頭所見とが合致しない事例があることを示す症例である。

　A 44-year-old and 72-year-old females were diagnosed with optic nerve hypoplasia associated with open-angle glaucoma in both eyes. The two cases showed different features in visual field and disc findings. One case showed,in the right eye,concentric constriction in the lower visual field,cuneiform defect inferiorly,and upper and lower Bjerrum scotomas. Heidelberg Retina Tomograph（HRT）showed notched rims matching the Bjerrum scotoma but no abnormal findings that correspond to field constriction or cuneiform defect. The other case showed bilateral cuneiform defect in the temporal visual field. The right eye had superior field defect. The left eye had upper and lower Bjerrum scotoma. HRT showed findings corresponding to cuneiform and Bjerrum scotomas. The present cases illustrate that discrepancies may be present between visual field and disc findings in optic nerve hypoplasia,particularly when associated with open-angle glaucoma.