Primary phlebitis of central nervous system revealed by black-blood magnetic resonance imaging

Primary phlebitis of the central nervous system (PPCNS) is a rare condition that might be a subset of primary angiitis of the CNS. In this case report, the patient was a 39-year-old man with a 2-week history of anterograde amnesia and abnormal behaviours. Black-blood MRI (BB-MRI) showed contrast enhancement of the left basilar vein and cerebral superficial veins. Angiography showed unremarkable change in arteries. After a thorough differential diagnosis, we diagnosed PPCNS and then administered methylprednisolone pulse and cyclophosphamide pulse. The neuropsychological symptoms and MRI findings gradually improved, and after 2 months, the dose of prednisolone was gradually reduced to 20 mg. No recurrence was observed. This case shows that BB-MRI may be useful for diagnosing PPCNS.

Associations between haemodynamics and wall enhancement of intracranial aneurysm

Background and purposePrevious studies have reported about inflammation processes (IPs) that play important roles in aneurysm formation and rupture, which could be driven by blood flow. IPs can be identified using aneurysmal wall enhancement (AWE) on high-resolution black-blood MRI (BB-MRI) and blood flow haemodynamics can be demonstrated by four-dimensional-flow MRI (4D-flow MRI). Thus, this study investigated the associations between AWE and haemodynamics in unruptured intracranial aneurysms (IA) by combining 4D-flow MRI and high-resolution BB-MRI.Materials and methodsBetween April 2014 and October 2017, 48 patients with 49 unruptured IA who underwent both 4D-flow MRI and high-resolution BB-MRI were retrospectively included in this study. The haemodynamic parameters demonstrated using 4D-flow MRI were compared between different AWE patterns using the Kruskal-Wallis test and ordinal regression.ResultsThe results of Kruskal-Wallis test showed that the average wall shear stress in the IA (WSSavg-IA), maximum through-plane velocity in the adjacent parent artery, inflow jet patterns and the average vorticity in IA (vorticityavg-IA) were significantly associated with the AWE patterns. Ordinal regression analysis identified WSSavg-IA (p=0.002) and vorticityavg-IA (p=0.033) as independent predictors of AWE patterns.ConclusionA low WSS and low average vorticity were independently associated with a high AWE grade for IAs larger than 4 mm. Therefore, WSS and average vorticity could predict AWE and circumferential AWE.

Black blood imaging of intracranial vessel walls

Traditional vascular imaging focuses on non-invasive cross-sectional imaging to assess luminal morphology; however, the vessel wall itself may be specifically involved in many diseases. Newer pulse sequences, and particularly black blood MRI of intracranial vessels, have brought a paradigm shift in understanding the pathophysiology of many vasculopathies. Black blood MRI of intracranial vessel walls can help in a range of pathologies with differing pathophysiology, including intracranial atherosclerosis, aneurysms, vasculitis and vasculopathy, moyamoya disease, dissection and vertebrobasilar hypoplasia. This review highlights how vessel wall imaging can contribute to the clinical diagnosis and management of patients with intracranial vascular pathology.

Wall enhancement segmentation for intracranial aneurysm

We present a tool for automatic segmentation of wall enhancement of intracranial aneurysms in black blood MRI. The results of the automatic segmentation with several configurations is compared to manual expert segmentations. While the manual segmentation includes some voxels of lower intensity not present in the automatic segmentation, overall the volume of the automatic segmentation is higher.