Usefulness of arterial spin labeling MR angiography as preprocedural mapping for the intra-arterial chemotherapy in patients with maxillary sinus cancer: A case report.

Arterial spin labeling (ASL) magnetic resonance angiography (MRA) (ASL-MRA) is a newly developed method that can visualize small arteries, particularly those running tortuously and inferiorly at slow flow rates. It provides excellent visualization of the external carotid artery system, with superior performance in visualizing the middle meningeal artery (MMA) compared to that of computed tomography angiography (CTA). Here, we report a case of maxillary sinus carcinoma in which ASL-MRA revealed an ipsilateral ophthalmic artery originating from the MMA that was not visualized on CTA. Volume rendering or maximum intensity projection images of CTA may fail to depict small arteries that run close to bony structures, including anomalies of the MMA originating from the external carotid artery system. In such cases, ASL-MRA may serve as a useful tool to easily visualize the arteries.