低剂量CT仿真结肠镜结合增强扫描对结直肠疾病的诊断价值

目的:评估低剂量CT仿真结肠镜结合增强扫描对结直肠疾病的诊断价值。方法:对104例受检者进行低剂量CT仿真结肠镜及增强扫描检查,将检查结果与结肠镜活检病理结果进行比较,计算低剂量CT仿真结肠镜诊断病变的敏感度和特异度,并分别记录低剂量和常规剂量扫描的CT容积剂量指数(CT dose index volume,CTDI vol)。结果:104例受检者中,阳性病变者91例,阴性13例。其中低剂量CT仿真结肠镜检出阳性者89例(89/91,97.8%),低剂量CT的CT辐射指数较常规CT平均降低60.59%。与常规剂量CT相比,低剂量CT仿真结肠镜对肠壁浸润程度、病变定性及腹膜后淋巴结的显示均稍差,而增强扫描有助于弥补这些不足。结论:低剂量CT仿真结肠镜检查可以有效地发现结直肠病变,且较常规CT的X线辐射剂量低;增强扫描适用于结直肠癌术前分期,低剂量CT仿真结肠镜结合增强扫描对结直肠疾病的诊断有较高价值。

Diagnostic Value of Low-Dose CT Virtual Colonoscopy Combined with Enhanced Scanning in Colorectal Diseases

Objective：To evaluate the value of low-dose CT virtual colonoscopy combined with enhanced scanning in the diagnosis of colorectal diseases. Methods..A total of 104 cases underwent low-dose CT virtual colonoscopy and enhanced scanning, and the examination results were compared with pathological results of colonoscopy biopsy, specimens the sensitivity and speci- ficity of low-dose CT virtual colonoscopy were calculated, and CT dose index volume（CTDI vol） of low-dose and conventional dose CT were recorded. Results： Among the 104 cases, 91 cases were positive, 13 cases were negative. And 89 cases （89/91, 97.8%） of the 91 positive cases could be diagnosed by low-dose CT virtual colonoscopy. The CT radiation index of low-dose CT was 60.59% lower than that of conventional CT. However, low-dose CT was slightly poorer in judgment of intestinal wall infiltration, lesion qualification and demonstration of retroperitoneal lymph nodes, compared with colonoscopy, but enhanced scanning could improve such deficiency. Conclusions： Low-dose CT colonoscopy can effectively demonstrate colorectal lesions with low radiation dose, and enhanced scanning has great advantages in the preoperative staging of colorectal cancer. Hence, the combination of them has great value in the diagnosis of colorectal diseases.