A clinical observation showed a slightly elevated and sharply demarcated plaque with vertical vessels seen on end straddling the upper cornea and superior limbus of left eye.

• 病患61岁男性，左眼轮部及角膜上半部长一片稍呈隆起的斑块，病理切片检查证实为结膜上皮原位癌已侵犯角膜。