良好な経過をたどった原田病患者の視機能の検討 特に夕焼状眼底との関連

Implication of fundus depigmentation on the visual functions in Harada disease

　原田病で中心視力が回復し，臨床的に治癒したと考えられる15例において，多方面より視機能を検討することを目的として，空間周波数特性（MTF），色覚検査（Lanthony's new color test,F-M 100-hue test等），EOGによるL／D比，中心CFF，および若年症例にのみ硝子体フルオメトリーを行った．

　MTFでは，夕焼状眼底を呈する群で全周波数に渡り著明な低下がみられたが，夕焼状眼底を呈さない群では正常者群と差がみられなかった．色覚およびEOG検査では同眼底を呈する2名3眼に異常がみられ，中心CFFおよび硝子体フルオトメリーでは全例正常と差がなかった．

　今回の検査で異常を示した例は夕焼状眼底出現例に限られ，同眼底を呈する例に見え方の不満を有する者が多いという自覚的訴えと一致した．

We evaluated visual functions in 15 cases in healed stage of Harada disease with visual acuity of 0.9 or over. Six cases (12 eyes) manifested diffuse depigmentation in the fundus when the diseases subsided. Nine cases (18 eyes) showed normally pigmented fundus. We tested modulation transfer function (MTF), color sense with Lanthony's new test and Farnsworth-Munsell's 100-hue test, L/D ratio in electrooculogram (EOG) and central criti-cal flicker fusion frequency (CFF) among others. These values were compared with those in age-matched normal subjects.

The MTF values showed significant attenuations in all spatial frequencies in cases with depigmented fundus. Cases with normal pigmentation showed normal MTF values. Abnormal color sense and L/ D ratio were found in 3 eyes of 2 cases with diffuse fundus depigmentation. No significant changes were observed in CFF and vitreous fluoro-photometry values.

In the present series, abnormal visual functions were found only in cases with diffuse fundus depig-mentation, or "sunset-glow fundus". This finding is compatible with the clinical ones, since patients with depigmented fundus tend to complain of visual problems in spite of good central vision.

Rinsho Ganka (Jpn J Clin Ophthalmol) 41(8) : 933-937, 1987