Variations in the popliteal artery branching in 342 patients studied with peripheral CT angiography using 64-MDCT.

PURPOSE: The objective of this study was to assess the utility of peripheral computed tomography angiography (CTA) using 64-multidetector computed tomography (64-MDCT) in the detection of variations in branching patterns of the popliteal artery. MATERIALS AND METHODS: The peripheral CTAs of 742 limbs in 342 patients who underwent peripheral CTA using 64-MDCT of the lower extremity due to various reasons were retrospectively reviewed. The anatomical variations in popliteal artery branching were assessed in 636 limbs from the same cohort of patients. RESULTS: Five hundred fifty-three (87 %) limbs had the usual branching pattern (type IA). Variations in the branching pattern of the popliteal artery were seen in 83 (13 %) limbs. The most common anatomical variation was trifurcation of the popliteal artery in 27 (4.2 %) limbs, with anterior tibial, posterior tibial, and peroneal arteries arising together with no true tibioperoneal trunk (type IB). CONCLUSION: The presence of variations in the anatomy of the popliteal artery could be of radiological and surgical importance in orthopedic interventions and various vascular surgery procedures. Peripheral CTA using MDCT is a suitable imaging modality for noninvasive evaluation of lower extremity arteries, and it may become the preferred method for evaluating variations in popliteal artery branching.

Is there a connection between perivascular space and subarachnoid space?

Perivascular spaces (PVSs) surrounding the walls of arteries, arterioles, and venules do not directly communicate with subarachnoid spaces. There are a few reports exhibiting subarachnoid hemorrhage (SAH) and intracerebral hematomas extending to the PVSs by leakage of the leptomeninges that surround arteries. In this report, we present 4 patients of whom 3 had SAH extending into the PVSs in the bilateral basal ganglia and 1 had extension of contrast medium to the PVSs after injection of the contrast medium into the lumbar subarachnoid space. The hemorrhage extending to the PVSs in our 3 patients with SAH could be explained by leakage of the leptomeninges surrounding the arteries. However, how the contrast medium extends to the PVSs is not clear. We think that, although speculative, incomplete or complete defect at the leptomeninges surrounding the arteries resulting in direct continuity between the subarachnoid space and the PVS allows that blood or contrast media to extend to the PVSs.