Mechanism and clinical value of 320-slice CT perfusion and CT angiography in peritumoral edema of parasagittal meningiomas

Abstract

Objective To explore the mechanism and clinical value of 320-slice CT perfusion (CTP) and CT angiography (CTA) in peritumoral brain edema of parasagittal meningiomas. Methods Sixty-six patients diagnosed as having benign parasagittal meningioma by imaging in our hospital from May 2010 to January 2015 were divided into non-peritumoral edema group (n=22) and peritumoral edema group (n=42) according to the cerebral MR T2 phase imaging. All patients were given 320-row CTP and CTA scan before surgery, and cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT) and time to peak (TTP) were obtained; and then, generated perfusion images and CTA images and fusion image were created. Results TTP of peritumoral tissues from the tumor margin 0.5 cm and 1.5 cm was [(28.1±3.3) s and (24.5±2.8) s, respectively in the peritumoral edema group, which was significantly longer than that in the non-peritumoral edema group ([14.8±1.3] s, P<0.05). Via comparison of the fused image, the lumen diameter of tumor-draining venous widened and shaped in appearance, and became relatively thin and straight in appearance in lumen diameter before entering the sinus, which suggested that the drainage was not free. Conclusion The TTP extension of tumor tissues and peritumoral brain tissues is the important characteristic for CTP scanning of peritumoral edema in meningiomas; poor blood return of tumor tissues may be the mechanism of peritumoral edema in meningiomas; fusion image has an important guiding significance for clinical surgery. Key words: 320-slice computed tomography perfusion; Spiral computed tomography angiography; Parasagittal meningioma; Peritumoral brain edema