颅脑CTP对Willis环后循环变异脑血流灌注的评价

利用头颈CT血管成像( CTA )技术筛查出单侧颅底动脉环后循环变异患者,分为变异优势侧组和劣势侧组,再根据前循环是否有变异分为前循环完整组和非完整组,后运用颅脑CT灌注( CTP)技术分别测量两组双侧大脑后动脉供血区域脑组织血容量( CBV)、脑组织血流量( CBF)、平均通过时间(MTT)、造影剂达峰时间(TTD)数据,运用统计学方法对优势侧和劣势侧进行配对t检验. 90例颅底动脉环后循环变异的患者中右侧后交通动脉发育不良或缺失30例,右侧大脑后动脉发育不良或缺失5例,左侧大脑后交通动脉纤细或缺失49例,左侧大脑后动脉缺失6 例. 前循环完整组73例;前循环非完整组17例,其中7例为前交通动脉缺失,10例为单侧大脑前动脉A1段发育不良. 前循环完整组后循环优势侧CBV、CBF、MTT、TTD与劣势侧各组经配对t检验,差异无统计学意义;前循环非完整组后循环优势侧CBV、TTD与劣势侧经配对t检验,差异无统计学意义,MTT、TTD 两组间比较差异有统计学意义( P<0. 05 ). 在前循环完整组,颅底动脉环后循环变异劣势侧与优势侧脑血流灌注无明显差异;在前循环非完整组,颅底动脉环后循环变异劣势侧MTT大于优势侧,CBF小于优势侧,与临床不明原因的晕厥可能有相关作用.

Using craniocerebral CT perfusion imaging to evaluate the cerebral blood flow perfusion of the posterior circulation variation of scull base arterial cycle

To assess the cerebral blood flow perfusion of basicranial artery posterior circulation variation with the combined application of head and neck CT angiography ( CTA) and craniocerebral CT perfusion ( CTP) . Patients suffering posterior communicating artery variation in unilateral basicranial arterious circle were screened out with head and neck CTA, and divided into advantageous variation-side group and disadvantageous variation-side group. Then based on whether or not there was anterior circulation variation, the patients were divided into intact anterior circulation group and non- intact anterior circulation group. With the application of craniocerebral CTP technolo-gies, the brain tissue CBV in bilateral posterior cerebral artery blood supplying areas was measured, along with CBF, MTT and contrast medium TTD. Besides, paired t test was conducted on the advantageous variation-side group and the disadvantageous variation-side group with statistical methods. Of the 90 patients with basicranial ar-tery posterior circulation variation, 30 ones suffered dysplasia or deficiency in right posterior cerebral communica-ting artery, 5 ones dysplasia or deficiency in right posterior cerebral artery, 49 ones thin or deficient left posterior cerebral communicating artery, and 6 ones deficiency in left posterior cerebral artery. The intact anterior circulation group included 73 patients, while the non-intact anterior circulation group 17 ones. Of them, 7 ones suffered ante-rior communicating artery deficiency, and 10 ones dysplasia in section A1 of unilateral anterior cerebral artery. Ac-cording to paired t tests on CBV, CBF, MTT and TTD between the advantageous posterior circulation side and dis-advantageous posterior circulation side of the intact anterior circulation group , there was no statistically significant difference. Paired t tests on CBV and TTD between the advantageous posterior circulation side and disadvantageous posterior circulation side of the non-intact anterior circulation group showed that there was no statistically significant difference;however, there was statistically significant difference ( P <0. 05 ) in MTT and CBF between the two groups. For the intact anterior circulation group with posterior circulation variation in basicranial arterious circle, there is no significant difference in cerebral blood flow perfusion between the advantageous variation side and the disadvantageous variation side;for the non-intact circulation group with posterior circulation variation in basicranial arterious circle, the disadvantageous variation side has greater MTT and smaller CBF than that of the advantageous variation side. This may be correlative to clinical syncope with unknown causes.