Use of single-slice thick slab phase-contrast angiography for the diagnosis of dural venous sinus thrombosis

The aim of this study was to examine the reliability of single-slice phase- contrast angiography (SSPCA) as a rapid technique for the investigation of suspected dural venous sinus occlusion. Images were obtained on 25 normal v olunteers to document the accuracy of SSPCA in the demonstration of slow fl ow states. Normal volunteers were imaged using sagittal and coronal SSPCA ( slice thickness 13 cm, matrix 256 x 256, TR 14 ms, TE 7 ms, flip angle 20 d egrees, peak velocity encoding rate 30 cm/s). Sinus patency and flow rate w ere confirmed by measurement of :flow in the superior sagittal and transver se sinuses using quantified single-slice phase difference images. Imaging w as performed in 50 patients undergoing routine brain scans in order to dete rmine the optimal slice orientation for clinical use. Twenty-one patients w ith suspected dural venous sinus thrombosis were also investigated with SSP CA and the diagnosis confirmed by one or more alternative imaging technique s. Imaging time was 29 s per acquisition and image quality was good in all cases. Variations in dural sinus patency and flow in normal volunteers were accurately predicted by SSPCA (kappa = 0.92). Use of a single angulated sl ice (130 mm thick, para-sagittal,image angled 30 degrees towards coronal an d 30 degrees towards :transverse) provided sufficient separation of right. and left-sided venous structures to allow use of a single projection. The p resence and extent of sinus occlusions in 14 patients and the absence of th rombosis rin 7 were accurately identified by SSPCA. Sensitivity and specifi city in this limited study were both 100 %. The SSPCA technique takes less than 30 s and provides a reliable and rapid technique for the diagnosis of dural venous sinus thrombosis.