もやもや病の9歳女児にみられた脈絡膜骨腫の1例

Choroidal osteoma in a nine-year-old girl with moyamoya disease

　9歳女児が1週間前からと推定される右眼視力低下で受診した。矯正視力は右0.3，左1.2であった。右眼底に，視神経乳頭から黄斑部に至る4乳頭径大の黄白色のわずかな隆起があり，辺縁は不整であった。腫瘤部の網脈絡膜に萎縮と網膜下出血があった。以前から存在した脈絡膜骨腫に新生血管が合併し，網膜下出血のために視力が低下したものと判断した。右眼に視神経乳頭陥凹の拡大があり，脈絡膜骨腫の影響があると推定した。左眼は正常であった。1歳時に左片麻痺があり，もやもや病と診断されていた。もやもや病と脈絡膜骨腫とは偶然に発症した可能性が高いと考えた。

A 9-year-old girl presented with visual impairment in her right eye since one week before. Her corrected visual acuity was 0.3 right and 1.2 left. Her right eye showed slightly elevated yellowish lesion white irregular borders of 4 disc diameters across extending from the disc margin to the macula. Chorioreti-nal atrophy and subretinal hemorrhage were presented in the lesion. She was diagnosed with longstanding choroidal osteoma. The impaired visual acuity appeared to be secondary to subretinal hemorrhage. The right eye showed enlarged excavation of the disc, apparently secondary to choroidal osteoma. Her left eye was in-tact. She had a history of left hemiplegia at the age of one year. She had been diagnosed with moyamoya dis-ease, or spontaneous occlusion of circle of Willis. The association of choroidal osteoma and moyamoya disease was interpreted as a chance occurrence.