Darstellung und Quantifizierung von liquorflussabhängigen Bewegungen intrakranieller Strukturen mittels MRT

Abstract

Background and Purpose: Brain pulsation is a well known observation in neurosurgery, but there is a lack of methods for its visualisation on MRI. We prospectively investigated ECG gated Cine True fast imaging with steady state precession (FISP) sequence on volunteers to test a sequence for demonstrating brain pulsation and CSF flow related movements of intracranial structures. The lamina terminalis of the third ventricle was chosen for quantification. Methods: Eleven healthy volunteers were investigated with prospectively ECG gated Cine True FISP in mid-sagittal plane. 50 phases were recorded per cardiac-cycle and volunteer. The change diameter of the optic recess was measured as a parameter for the movement of the lamina terminalis. Results: All volunteers already demonstrated pulsatile changes by the visual impression. The mean diameter of the optic recess was 2.5 mm. The greatest change in diameter in one individual was 1.5 mm. The mean change in diameter was 40% during one heart cycle. The spatial resolution especially for moving arachnoidal membranes seemed to increase. Conclusion: Cine True FISP sequence is a well suited method for investigations of passive movements of the ventricular system. It shows pulsations of the brain as well as passive changes caused by CSF flow with high temporal and spatial resolution. The examined movement of the lamina terminalis is a valuable parameter for demonstrating changes through CSF flow.