三维CT全脑灌注血容量成像在超急性期脑梗死的初步应用

Preliminary application of 3D CT whole brain perfused blood volume imaging in hyperacute cerebral infarction

目的探讨三维CT全脑灌注血容量成像在超急性期脑梗死的应用价值。方法对25例发病6h以内的超急性期脑梗死患者行常规螺旋CT平扫及CT血管造影(CTA)检查,分析CT平扫表现,并使用Siemens三维NeuroPBV软件对CTA源图像和CT平扫图像进行减影处理,获得三维彩色PBV图像。比较CT平扫与PBV图像对急性脑缺血灶的检出率。全部病例于发病后2～7d复查CT平扫。对PBV图像显示的脑灌注异常区体积与复查CT平扫显示的梗死灶体积进行比较分析,并采用Spearman相关分析方法对其进行相关性检验。结果25例患者首次头颅CT平扫12例发现早期脑梗死征象,13例未发现异常,重建三维PBV图像均发现与临床症状相对应的脑灌注异常区。复查CT平扫图像上25例患者最终梗死灶体积与PBV图像上灌注异常区体积存在显著正相关(rs=0.837,P<0.001)。结论PBV图像能够三维显示急性脑缺血全脑灌注信息,对早期发现脑缺血、全面评价缺血范围、避免病灶漏诊有重要价值。

Objective To observe the diagnostic value of 3D CT whole brain perfused blood volume （PBV） in hyperacute cerebral infarction patients. Methods Conventional cerebral plain CT. and CT angiography （CTA） were performed on 25 patients with hyperacute stroke within 6 h. 3D PBV calculations were based on the CTA and the plain CT images covering the whole brain. The detection rate of ischemia on 3D PBV images was compared with the baseline plain CT. Follow-up CT ex- aminations for the depiction of definite infarction were obtained at 2--7 d. The ischemic lesion volume on 3D PBV images was compared with the follow-up plain CT. Results Baseline plain CT demonstrated early isehemic signs in 12 of 25 patients. 3D PBV demonstrated perfusion deficits corresponding to clinical symptoms in all the 25 patients. Moreover, statistical significant correlation was found between the ischemic lesion volume on 3D PBV and the follow-up infarct （Spearman＇s rs =0. 837, P〈0. 001）. Conclusion In hyperacute cerebral infarction patients, 3D PBV images from CTA source images and plain CT images can improve detection rate of ischemia by avoiding omission of lesions and assess the full extent of ischemia that correlating well with the follow-up infarct.