圆窗缺失是一种罕见的先天性缺陷疾病,曾有报道为综合征或单纯发病。目前,关于单纯性、非综合征性圆窗缺失的报道仅有3例,且为术中诊断。该作者报道1例术前通过高分辨CT扫描在中耳内镜下诊断先 Window missing is a rare congenital defect disease, there have been reported as a syndrome or a simple disease. At present, there are only 3 cases of simple and non-syndromic circular window missing, and it is an intraoperative diagnosis. The authors report a case of preoperative diagnosis of middle ear through high resolution CT scan first