Study On The Nature And Pathology Of Carotid Plaques By GSI Technique

Objective: By using CT(computed tomography) gemstone spectral imaging(GSI), we comprehensively analyzed the tissue component and defined the characters of the carotid artery plaques in patients with carotid atherosclerosis(CA), providing early warning of ischemic risk and intervention therapy with imaging basis.Methods: 42 patients were examed and screened by color Doppler ultrasound and diagnosed as carotid atherosclerosis(CA). The patients were divided into two groups, group A and group B. 20 of them were received carotid endarterectomy(CEA) as the control involved in group B. The plaques were taken to analyze by histopathology and the characteristics were recorded. Another 22 patients without receiving CEA were involved in group A. All the patients were received computed tomography angiography(CTA). The quality control(QC) images(140Kvp) and the 70 kev single energy images were transferred to GE energy spectrum CT workstation AW4.4. Calculated separately and compared the contrast to noise ratio(CNR) under the condition of between QC images and 70 kev images. Reconstructed the plaques in group A and B to get the spectral HU curve. The slope of the curve, the iodine concentration(100ug/m L) and the Effective-Z were recorded and compared. According to the sensitivity and specificity of the three mentioned above, evaluated the measuring effects on different kinds of plaque.Results: The average CNR under the condition of 70 kev in group A and B was higer than the value unther the QC image, significantly(P<0.01). Using the CNR under the condition of 70 kev to determine the character of the plaques was more suitable than the condition of QC image. The sensitivity and specificity of spectral HU curve slope on fibrous plaques were higher, comparing with other plaques, while the sensitivity was lowest and the specificity was the highest on lipid plaques. The sensitivity and specificity of both the iodine concentrationand Effective-Z on the three kinds of plaque were lower than the slope of the curve, which indicated that spectral HU curve slope was the effective and credable index to evaluate different kinds of plaque.Conclusions: GSI was the newly reliable method to study on CA by quantitative analysis and typing on plaques. Base on the different parameters from GSI, we could analyze the CA plaques quantitatively and qualitatively, with higer sensitivity and specificity.