男児の両眼に発生した脈絡膜骨腫の1例

Bilateral choroidal osteoma in a male child

　13歳男児に右眼視力低下が突発し，2日後に受診した。矯正視力は右0.1，左1.2であった。両眼眼底に12×10乳頭径の橙赤色病変があり，超音波とCTを含む諸検査から脈絡膜骨腫と診断した。右眼眼底には網膜下出血があり，光干渉断層計（optical coherence tomography：OCT）で網膜分離症を伴う網膜剥離があった。右眼矯正視力は2か月後に0.8,8か月後に1.0に自然回復した。フルオレセイン蛍光眼底造影（fluorescein angiography：FA）とインドシアニングリーン蛍光眼底造影（indocyaninegreen angiography：IA）とで異常蛍光と検眼鏡的な病変部の範囲が一改せず ，FAで造影された範囲が実際の骨腫の存在部位であると考えられた。OCTは網膜剥離などの同定に有用であったが，骨腫の反射像は明瞭でなかった。

A 13-year-old boy presented with sudden visual loss in his right eye since 2 days before. His corrected visual acuity was 0.1 right and 1.2 left. Both eyes showed an orange-red lesion of 12 by 10 disc diameters in size. Examinations including computerized tomography and ultrasonography led to the diagnosis of choroidal osteoma. The right eye showed a subretinal hemorrhage. Optical coherence tomography (OCT) showed retinal detachment and retinoschisis in the right macular area. The right visual acuity underwent spontaneous recovery to 0.8 2 months later and to 1.0 8 months later. There were discrepancies in the area of patholological lesion among findings by fluorescein angiography, indocyanine green angiography, and ophthalmoscopy. It appeared that fluorescein angiography gave the actual extent of choroidal osteoma. OCT was useful in detecting retinal detachment and retinoschisis but not in identifying the osteoma.