超音波生体顕微鏡により診断が可能であった虹彩毛様体嚢胞に虹彩悪性黒色腫を合併した1例

A case of iridociliary cyst with malignant melanoma of the iris diagnosed by ultrasound biomicroscopy

　66歳男子の両眼に虹彩毛様体嚢腫が発症した。のち，左眼の虹彩に黒褐色の腫瘍が生じた。超音波生体顕微鏡（UBM）検査で，嚢腫と腫瘍は明瞭に鑑別された。摘出した腫瘍の病理組織像は，嚢腫に合併した混合型悪性黒色腫で，UBM所見とよく一致した。虹彩毛様体腫瘍の診断にUBMは有効であった。

A 66-year-old male developed iridociliary cyst in both eyes. The left eye later showed dark brown tumor of the iris. Examination by an ultrasound biomicroscope, UBM, clearly distinguished the iris tumor from the cystic lesion. Histological studies of the excised tumor showed mixed type malignant melanoma associated with iridociliary cyst lined by nonpigmented epithelium of the ciliary body. UBM was thus useful in the clinical diagnosis of iris tumor.