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Restenosis after carotid endarterectomy (CEA) is one of most significant complications. There is no previous report about MRI findings of restenotic lesions and preoperative plaques. The purpose of this study was to evaluate the initial and recurrent plaques in patients with restenosis after CEA by using black-blood MRI (BB-MRI). Three patients who underwent carotid artery stenting for restenosis after CEA were included in this study. The relative signal intensities (rSI) of the initial and recurrent plaques were calculated with reference to the sternocleidomastoid muscle on T1-weighted images (T1WI) and the submandibular gland on T2-weighted images (T2WI). This study investigated the rSI characteristics and morphology of the initial and recurrent plaques. All patients had restenosis within 1 year after CEA. The rSI values of the preoperative lesion were not high on T1WI and were high on T2WI in all cases (T1WI/T2WI: 0.63/2.43 in Case 1, 1.00/1.29 in Case 2, and 1.13/1.70 in Case 3). The morphology of the initial plaques was eccentric in 2 cases and concentric in 1 case. The rSI values of restenosis were high on T2WI in all cases (T1WI/T2WI: 1.09/1.20 in Case 1, 1.31/1.50 in Case 2, and 1.23/1.70 in Case 3). The morphology of restenotic lesions was concentric in all cases. The high rSI on T2WI and concentricity of the restenosis after CEA suggest early restenosis (intimal hyperplasia). The low-iso rSI on T1WI and high rSI on T2WI of the preoperative plaques are associated with restenosis after CEA. BB-MRI may be useful to evaluate and predict restenosis after CEA. (Received: May 7, 2012, Accepted: September 10, 2012).

Background: An association between magnetic resonance imaging detection of intraplaque hemorrhage and the risk of cerebral ischemic events has been described. However, few studies have followed patients with intraplaque hemorrhage., Objective: We used 3-dimensional gradient-echo black-blood T1-weighted imaging (screening BB [S-BB]) as a magnetic resonance imaging sequence to evaluate acute cerebrovascular stroke. The association between S-BB high signal plaques and the risk of subsequent ipsilateral ischemic events was investigated., Methods: A total of 928 consecutive patients hospitalized for a stroke or transient ischemic attack according to the Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification were evaluated. Recurrence was retrospectively evaluated in S-BB-positive patients and patients with severe stenosis (SS) (≥70%) by magnetic resonance angiography. Based on clinical and imaging findings, recurrence was defined as a carotid artery stroke or transient ischemic attack that developed after hospital discharge as an initial event., Results: Sixty-six patients were S-BB positive and 62 patients had severe stenosis (S-BB positive with SS, 32 patients; S-BB negative with SS, 30 patients; S-BB positive without SS, 34 patients). During a mean follow-up period of 9.1 months, 7 S-BB-positive patients with SS (18.7%) and 1 S-BB-negative patient with SS (3%) had a recurrent event (P = .051). In the S-BB-positive group, in 34 patients without SS, the recurrence rate was 14.7% (5/34); the difference in the recurrence rate between S-BB-positive group with and without SS was not significant (P = .34)., Conclusion: Patients with carotid artery lesions and intraplaque hemorrhage tend to be at higher risk of a subsequent ipsilateral ischemic event. Risk evaluation of carotid artery disease should include plaque characteristics.

Recent diffusion-weighted imaging (DWI) studies describe a relevant ischemic lesion in almost half of all patients with transient ischemic attack (TIA). We report 3 cases of TIA in which the ischemic lesions were recognized on DWI at a later date ("late-imaged TIA"). Three men (average age, 72.7 years) were admitted to our hospital on complains of monoparesis or sensory disturbance in their right arms. On admission, no apparent ischemic lesion was detected by DWI; however, spotty lesions were apparent in the left precentral or postcentral gyrus on hospital days 2-5. The neurological symptoms resolved within 24 hours, and all the cases were clinically diagnosed as TIA. Carotid MRI revealed low-grade stenosis of the left internal carotid artery with atherosclerotic plaque, characterized as so-called "vulnerable plaque". These findings suggest that the carotid atherosclerotic plaque lead to artery-to-artery embolism. Carotid MRI is considered useful as an adjunct to other imaging modalities in the diagnosis of late-imaged TIA.

Purpose: Replaced posterior cerebral artery (PCA), defined as a hyperplastic anterior choroidal artery (AChA) supplying all branches of the PCA, is an extremely rare anatomical variation. To the best of our knowledge, there are only a few reports of replaced PCA. Methods: Herein, we report a case of replaced PCA diagnosed by digital subtraction angiography. Results: A 76-year-old woman visited a neurosurgical clinic because of headache and vertigo. Magnetic resonance imaging and magnetic resonance angiography incidentally revealed a left internal carotid artery aneurysm. She was referred to our hospital for further examination and treatment of the unruptured intracranial aneurysm. Left internal carotid angiography revealed a paraclinoid aneurysm. We also incidentally found an anomalous hyperplastic AChA distal to the aneurysm. This hyperplastic AChA supplied not only the AChA territory but also the entire PCA territory. No vessels that could be a normal AChA or posterior communicating artery were identified along the left internal carotid artery. Vertebral angiography demonstrated that the left PCA was not visualized. With these findings, we diagnosed anomalous hyperplastic AChoA in this case as replaced PCA. Conclusion: Careful imaging assessment is important to identify replaced PCA. Both direct findings of a hyperplastic AChA course and perfusion territory and indirect findings of the absence of the original PCA are useful in the diagnosis of replaced PCA. [ABSTRACT FROM AUTHOR]

The intracranial pressure value during shunt surgery was 140 mmH SB 2 sb O. Magnetic resonance angiography (MRA) 3 months postoperatively demonstrated complete occlusion of the treated aneurysm and bilateral dilated middle meningeal arteries (MMAs), which was also seen 1 month postoperatively (Fig. Conclusion We reported an extremely rare case of spontaneous closure of SSS-DAVF with CVR after SAH treatment, including treatment for secondary hydrocephalus. 4Follow-up angiogram 6 months postoperatively showing spontaneous closure of the dural arteriovenous fistula Discussion Herein, we presented a rare case of spontaneous closure of SSS-DAVF with CVR after treatment of SAH due to a ruptured intracranial aneurysm. [Extracted from the article]

A persistent trigeminal artery is the most common persistent carotid-vertebrobasilar anastomosis, while persistent trigeminal artery variants involve termination at the cerebellar artery without connecting to the basilar artery. Internal carotid artery hyperplasia is also a rare congenital anomaly. To the best of our knowledge, there are no reports of persistent trigeminal artery variant associated with ipsilateral hypoplasia of the internal carotid artery. Herein, we report a case of a 44 year-old woman who visited a neurosurgical clinic because of chronic headaches. Magnetic resonance angiography showed impaired delineation of the left internal carotid artery, and she was referred to our hospital for catheter angiography. Angiogram revealed left internal carotid artery hypoplasia and a left persistent trigeminal artery variant that terminated at the left anterior inferior cerebellar artery. Computed tomography bone images showed a narrow left carotid canal. We diagnosed congenital hypoplasia of the left internal carotid artery concomitant with ipsilateral persistent trigeminal artery variant. Careful imaging assessment is important for identifying persistent trigeminal artery variant when associated with ipsilateral internal carotid artery hypoplasia. [ABSTRACT FROM AUTHOR]