定型網膜色素変性症の視野に関する検討

The visual field in typical retinitis pigmentosa:An investigation in 14 hospitals

　定型網膜色素変性症の経過や予後の説明に必要な資料を得る目的で，226例444眼の残存視野と年齢，経過年数との関連について全体および遺伝形式別に検討し，さらに視力との関連についても検討した。視野20°以下の眼は20〜39歳で49％，経過年数20年未満で53％であった。また41°以上は20歳未満で54％，経過年数20年未満で27％であった。遺伝形式別比較では，常染色体優性が常染色体劣性よりも障害が軽い傾向が認められた。視野狭窄は経過年数30年まで徐々に進行し，10°前後の視野になるとその後は進行が遅くなる傾向がみられた。視野と年齢および経過年数との間には負の相関があり，視力との間には正の相関があった。以上の結果は患者の職業選択のさいや経過の理解のために役立つと思われる。

For the purpose of obtaining the information on the natural course of typical retinitis pigmentosa (RP), we studied the visual fields of 226 RP patients (444 eyes) with regards to genetic type, age, period since onset and visual acuity. The proportion of visual field deterioration to 20 degrees or less was 49% of eyes whose ages were between 20 and 39 years and 53% of eyes whose periods since onset were less than 20 years. Compar-ison of the visual fields among genetic types showed that visual field loss of autosomal domi-nant type was milder than that of autosomal reces-sive type. The tendency that visual fields gradually constricted over the 30 years since onset, and then remained at about 10 degrees for a long time, was found.

The degrees of visual field correlated with age, period since onset and visual acuity. These results may be helpful for patients to decide their occupa-tions and to understand their prognosis.