The Usefulness of a 3D Roadmap of Occluded Vessels Created from Rapid 3D Proton Density-Weighted Imaging for Mechanical Thrombectomy.

Objective: Mechanical thrombectomy (MT) for acute ischemic stroke usually requires blind procedures when endovascular devices are advanced into the occluded vessels. Therefore, the visualization of occluded vessels could potentially achieve safer procedures, shorter procedural time, and progression of the reperfusion rate. We report on the usefulness of a novel technique in which a 3D roadmap of occluded vessels was created from a rapid 3D proton density-weighted (PDW) variable refocusing flip angle and turbo spin echo (VRFA-TSE) method. Case Presentation: 3D PDW VRFA-TSE imaging was performed in addition to routine MRI for 2 patients with middle cerebral artery occlusion. With the adjustments to the imaging parameters, we were able to perform 3D PDW imaging in less than 1 minute. Subsequently, a 3D image of the occluded vessels was constructed from these images. To create a 3D roadmap, the 3D PDW images were positioned with cone beam CT images obtained before MT using 3D-3D fusion. Because a neurological technician performed the imaging processing while doctors and nurses prepared for MT, practical loss time was approximately 2 minutes. MT was performed with reference to the 3D roadmap, and the occluded lesion was recanalized without complications in both patients. The 3D roadmap of the occluded vessels was well-matched with the recanalized vessels. Conclusion: A 3D roadmap created from rapid 3D PDW imaging is a useful assistance technique for MT that allows the visualization of occluded vessels.