Using Osirix for Pre-Surgical Planning in Microvascular Decompression Surgeries

INTRODUCTION: Both trigeminal neuralgia (TN) and hemifacial spasms (HFS) cause vascular compression of the fifth and seventh cranial nerves, respectively, at the root entry zone. This study proposes a new technique for using both three-dimensional (3D) constructive interface in steady state (CISS) magnetic resonance imaging (MRI), magnetic resonance angiography (MRA), and computerized tomography angiography (CTA) to show vascular compression on the trigeminal and facial nerves.
METHODS: The study included 10 patients presenting with TN and HFS. The post-processing software Osirix was used to combine pre-operative 3D CISS MRI, MRA, and CTA to render a manipulative 3D image. This 3D image can be printed and used to show the vascular compression before the surgery.
RESULTS: Of the 10 patients, four were male and six were female. All radiological imaging was imported to the Osirix DICOM Viewer. The vascular compression was shown in nine of the patients. In nine patients displaying vascular compression were found to have anatomic consistency (determined during surgery) to that of the 3D model. One patient did not display vascular compression in either the 3D models or images.
DISCUSSION AND CONCLUSION: The use of 3D CISS MRI, MRA, and CTA to create manipulative 3D images and models was shown to be useful in pre-operative surgical planning for patients with symptoms of vascular compression, for whom previous medical interventions had failed. If venous compression is not observed, it is important to be aware of the potential to compression of a vein and various other non-vascular lesions.