光干渉断層計を用いた緑内障眼における視神経乳頭形状の解析

Morphometry of the glaucomatous optic disc using an optical coherence tomography

（P−51）　開放隅角緑内障38眼で，乳頭陥凹の形状と視野変化の関係を検索した。乳頭形状の評価には光干渉断層形（OCT）を，視野測定にはHumphrey視野計のプログラム30-2を用い，各測定要素を回帰分析で解析した。乳頭の陥凹／直径比（C／D比）と，MD値とPSD値とには有意な相関があった（MD：r＝0.328,p＝0.0443,PSD：r＝0.354,p＝0.0294）．乳頭の下掘れ部の直径／乳頭直径比（UD／D比）とMD値には相関がなく（r＝0.196,p＝0.2390），PSD値には有意な相関があった（r＝0.342，p＝0.0355）。乳頭の下掘れ部の直径／乳頭陥凹比（undermining index：UI）とMD値には相関がなく（r＝0.092,p＝0.5838），PSD値にも相関しなかった（r＝0.073,p＝0.6622）。以上，乳頭陥凹の下掘れ現象と視野には相関がなかったが，下掘れ現象を客観的に評価できる点でOCTは有用であった。

We evaluated the morphology of disc excavation and visual field defect in 38 eyes of chronic open-angle glaucoma. Changes in the optic disc was measured by an optical coherence tomograph (OCT). The visual field was ex-amined using Program 30-2 of Humprey Field Analyzer. The parameters were analyzed by a linear regression model. The cup/disc ratio (C/D) was linearly correlated with mean deviation (MD) of visual field (r=0.328, p=0.0443) and with pattern standard deviation (PSD) (r=0.354, p=0.0294). The undermining diameter/disc ratio (UD/D was line-arly correlated with PSD (r=0.342, p=0.0355) and not with MD (r=0.196, p=0.2390). The undermining index (UI) , or undermining diameter/cup ratio, was correlated neither with MD (r=0.092, p=0.5838) nor with PSD (r=0.073, p=0.6622). The findings show the absence of undermining of the optic disc as related to the visual field defect. Linear tomography with OCT was useful in the quantative evaluation of undermining of the glaucomatous optic disc.