光学相干断层成像与二维超声对实验性早期动脉粥样硬化诊断的灵敏度比较

目的:通过颈动脉粥样硬化模型评价二维超声与光学相干断层成像(optical coherence tomography,OCT)在早期病变中的检测效果。方法:选择新西兰大耳白兔40只。高脂饮食2周后,进行球囊损伤,术后继续高脂喂养4周。第6周时对兔的右侧颈总动脉进行二维超声检测和OCT检测。检查完成后猝死所有动物,取病理进行HE染色,免疫组化观察巨噬细胞含量。随后处理各组动物,留取动物的颈总动脉组织,进行免疫组化(CD68)及HE染色。结果:病理证实17只(43%)兔出现Ⅲ型病变:OCT证实发生动脉粥样硬化改变15只;超声检测到有内膜增厚7只,检测的灵敏度(即真阳性的检出率,88%vs.41%,P0.01)。病理证实8只兔(20%)出现Ⅱ型病变,OCT发现Ⅱ型病变5只;超声未检测到血管壁有异常改变,灵敏度(62%vs.0%,P0.05)。病理证实13只兔(33%)有Ⅰ型病变:OCT检测发现I型病变5只;超声未检测出管壁有异常改变,灵敏度(38%vs.0%,P0.05)。结论:OCT诊断实验性早期的动脉粥样硬化的灵敏度高于二维超声。

Diagnostic value of two-dimensional ultrasound and optical coherence tomography for early-stage atherosclerosis

AIM:To assess the diagnostic value of two-dimensional ultrasound and optical coherence tomography (OCT) for early-stage atherosclerosis on experimental rabbit carotid artery atherosclerotic model. METHODS: Forty New Zealand white rabbits were fed with a high-fat diet for 2 weeks before balloon injury and then were given a high-fat diet for another 4 weeks. At week 6, the right common carotid artery was scanned by two-dimensional ultrasound followed by OCT examination. The rabbits were then sacrificed and their arteries were fixed for serial hematoxylin-eosin staining. Macrophage content was semiquantified by immunostaining of CD68 antigen-antibody reaction. RESULTS: Histopathology confirmed that 17 (43%) rabbits had type III lesions. OCT showed atherosclerosis plaque formation in 15 rabbits and two-dimensional ultrasound showed intima thickening in only seven rabbits (positive rate: 88% vs. 41%, P<0.01). Histopathology confirmed that eight (20%) rabbits had type II lesions and 13 (33%) rabbits had type I lesions. OCT showed type II lesions in five rabbits, whereas two-dimensional ultrasound showed no abnormal changes in vascular walls (positive rate: 62% vs. 0, P<0.05). OCT showed type I lesions in five rabbits, whereas two-dimensional ultrasound showed no abnormal changes in vascular walls (positive rate: 38% vs. 0%, P<0.05). CONCLUSION: Both two-dimensional ultrasound and OCT demonstrate some diagnostic value for early-stage atherosclerosis, but OCT can provide a much more precise intravascular atherosclerosis image of early-stage atherosclerosis.