Clinical Study On Intima-media Thickness,Ultrasound Integrated Backscatter And Endothelium-dependent Dilation In Patients With Cerebral Infarction

The cerebral infarction has become the third lethal reason secondary to cardiac diseases and tumors. The examination of carotid arteries can be used to e-valuate the pathologic circumstances of intercerebral arteries. It is important to determine the risk of cerebral ischemia caused by carotid plaque, which can provide a feasible reference index for therapy. Endothelial dysfunction exists in the patients of atherosclerosis. We can use color Doppler ultrasound to evaluate the artery endothelial function.It is difficult to characterize the components of plaque by using conventional 2DE techniques. IBS is a new ultrasonic technique for tissue characterization. This study was designed to quantitate the carotid plaque of patients with cerebral ischemia and infarction using IBS. Therefore, we can get a useful parameter for the risk of carotid plaque in cerebral ischemic diseases.Material136 adults were enrolled in this study. 76 patients (men 47,women 29,average age 62yrs) , 60 control subjects ( men 35, women 25, average age 59yrs).Data was acquired by using Philips Sonos 5500 ultrasonic system equipped with IBS analysis software with a 7.5 MHz linear - array transducer.Methods1. 2DE imagingAll the objects in this study lay in the supine position, The carotid arteries were examined bilaterally in the area of common carotid artery ( CCA) the carotid bifurcation ( BIF) internal carotid artery (ICA) and external carotid artery (ECA). The diameters of all the arteries and the intima - media thickness (IMT) of the CCA were measured.2. Definition the plaquesIMT^l. 20mm or 0. 5mm thicker than the place of neighbour it, or 1. 5 times more than the place of neighbour it, or blood defect in some place of lumen of blood vessel by color imaging, the area of defect was more than 10mm2.3. Determining the rate of stricture of arteryComputing the rate of stricture of artery: the rate of stricture of artery = (1 - A/N) x 100%. A was area of narrow plaque, N was normal area of lumen.4. Color Doppler flow imagingCombined 2DE imaging with color Doppler flow imaging,it was determined to fillness in lumen with blood flow.5. The measurement of spetral DopplerPeak systolic velocity ( S ) mean velocity ( N ) end - diastolic velocity (D) pulsatility index (PI) resistance index (RI) were measured using spectral Doppler.6. The detection on plaques by IBS technichIntergrated backscatter system was preset and data was acquired: After swithing on AD - IBS procedure, we acquired digital integrated backscatter image sequences of the CCA lumen and the parts of weak echo low echo and high density echo according to machine settings mentioned above.7. The examination of vascular endothelial function by ultrasound8. Statistical analysisData was analyzed by SPSS (vertion11.0) software. P<0.05 was considered statistically significance.ResultsThe value of IMT in CCA( 1.17 +0.24mm) in patients was higher than that(0.77 ±0.17mm) in the control group. The results indicated that the diameters of CCA(8.44 ± 1.16mm) ICA(6.65 ± 1.04mm) ECA(5.58 ±0.90mm) and BIF(10.45 ± 1.47mm) respectively were wider than those of CCA (7.91 ±0. 88mm) ICA(5. 85 ± 0. 65mm) ECA (4. 95 ± 0. 64mm)^BIF(9. 68 ± 1. 01mm) in the control group. The value of PI in CCA (1. 86 ±0.41) ICA( 1. 17±0.37)ECA (2.57±0.92) and the RI in CCA (0.78 ±0.01) ICA(0. 64 ±0.01) ECA(0.84 ±0.01) in patients respectively were higher than those of PI in CCA( 1.46 ±0.40) ICA( 1.00 ±0.32),ECA (1.95±0.47) and RI in CCA(₀.72±0.11) ICA (0.60±0.11), ECA (0.80±0.01) . The rest parameters had not statistical significance.49 subjects of 76 patients had carotid atherosclerotic plaques. The incidence rate was 64% , while it was 36% in control group. The incidence rate of plaque were much higher than that in control group, and the occurrence rate (37.9% )of stenosis of the artery in patient group were much higher than that (11.1% ) in control group.In the patient group the number of the plaque in ICA was the most, a...