Brain Perfusion Imaging in a Case of Cerebral Sinus Thrombosis – Comparison between Ultrasonic and Magnetic Resonance Imaging

Background: The neurosonological assessment of brain perfusion has been improved recently by more efficient imaging modes like bilateral Phase Inversion Harmonic Imaging (PIHI) enabling the ultrasonic detection of cerebral perfusion deficits in acute ischemic stroke. The aim of this case report is to compare findings from PIHI with findings from perfusion-weighted magnetic resonance imaging (pw-MRI) in order to examine the diagnostic value of PIHI in cerebral venous thrombosis. Methods: A 50-year-old female patient with thrombosis of right-sided transverse sinus, superior sagittal sinus, straight sinus and vein of Galen was examined with bilateral PIHI using a Siemens Sonoline® Elegra system, equipped with a 2.5MHz phased array transducer. The ultrasound contrast agent was applied following the bolus kinetic approach (2.5 mL SonoVue® followed by 10 mL NaCl). Time-to-peak intensity (TPI), peak intensity (PI) and peak width (PW) were determined from a fitted model function from different regions of interest (ROI), followed by a region-wise and pixel-wise analysis of data. Parameters were compared with findings of established pw-MRI. Results: In region-wise analysis of PIHI a prolonged TPI (39.2s) in the posterior parietal ROIs compared to the median of TPI of the other examined ROIs (32.3s) was detectable. The TPI delay was represented in pixel-wise analysis. These findings were comparable to the observed time-to-peak (TTP) delay in pw-MRI. In accordance with previous published data for pw-MRI in cerebral venous thrombosis, increased Mean-Transit-Time (MTT) values were detectable, while the determination of cerebral blood volume (CBV) showed no pathology. Conclusions: For the first time perfusion pathologies in cerebral sinus thrombosis were documented by means of ultrasonic evaluation. Furthermore, it was possible to compare ultrasonic and MRI findings, which demonstrated similar results. In the future, ultrasonic brain perfusion imaging, as an easy available, bedside diagnostic tool might be helpful to diagnose and monitor cerebral venous thrombosis.