Ruptured thrombosed vertebral artery dissecting aneurysm treated with staged flow diverter after prediction of the rupture point by vessel wall MRI.

The safety and feasibility of using staged flow diverter (FD) for ruptured cerebral aneurysms, in which coil embolization is performed in the acute phase and FD is deployed in the subacute phase, has recently been reported. This strategy requires assuming the rupture point and performing coil embolization. Although vessel wall magnetic resonance imaging (VW-MRI) has been reported to be useful in predicting the rupture point of aneurysms, its use with staged FD has not yet been reported. We report the first case of staged FD with preoperative contrast-enhanced VW-MRI to predict the rupture point for partially thrombosed vertebral artery dissecting large aneurysm involving posterior inferior cerebellar artery (PICA) origin. This approach achieved a very good outcome, not only completely occluding the aneurysm, but also reconstructing the parent artery while maintaining the patency of the PICA.

Partially thrombosed giant basilar artery aneurysm with attenuated contrast enhancement of the intraluminal thrombus on vessel wall MRI after flow diversion treatment: illustrative case.

BACKGROUND: The effect of vessel wall magnetic resonance imaging (VW-MRI) enhancement in partially thrombosed aneurysms has previously indicated aneurysmal instability and a rupture risk. However, whether the contrast effect of the wall changes before or after flow diversion treatment is still under investigation. OBSERVATIONS: The authors report a case of a partially thrombosed basilar artery aneurysm that increased in size over a short period, worsened brainstem compression symptoms, and was treated with a flow diverter stent with good results. In this case, VW-MRI after surgery showed a reduced contrast effect on the intraluminal thrombus within the aneurysm. The aneurysm thrombosed and markedly regressed over the next 5 months, with remarkable improvement in the brainstem compression symptoms. LESSONS: This finding on VW-MRI may indicate an attenuation of neovascularization in the thrombus wall and be a sign of aneurysm stabilization.

Low NIHSS score large vessel occlusion caused by infective endocarditis treated with thrombectomy.

OBJECTIVES: Large vessel occlusion (LVO)-related acute ischemic stroke due to infective endocarditis (IE) is a rare condition. At onset, most patients are severely ill, whereas on rare occasion, they develop mild neurological symptoms. As far as we are aware, this is the first report of IE related internal carotid artery (ICA) occlusion with low National Institutes of Health Stroke Scale (NIHSS) (<6) score treated with endovascular thrombectomy. CASE PRESENTATION: A 24-year-old woman had undergone dental treatment 3 weeks before and had a persistent low-grade fever for a week. She presented to the emergency department with a chief complaint of motor weakness of the right upper limb after waking up. She had only mild paralysis of the right upper limb (NIHSS score 1). Magnetic resonance imaging showed scattered infarcts in the left frontal lobe and cerebral angiography showed that the left ICA had been occluded immediately distal to its origin. The symptom disappeared after the occluded artery was completely recanalized by mechanical thrombectomy. On postoperative day 1, blood cultures were positive and echocardiography was performed, which revealed a verrucous mitral valve and a diagnosis of IE. On postoperative day 2, the patient underwent cardiac surgery for valve replacement. Thereafter, there was no recurrence of cerebral infarction, and the patient was discharged home on day 50 with a modified Rankin Scale 0. CONCLUSIONS: Early endovascular thrombectomy for low NIHSS score LVO due to IE resulted in a good treatment course. IE should be part of the differential diagnosis of LVO in the young patients.

Cone-beam CT-assisted microcatheter tip placement at the shunted pouch entry zone: A technical note for anterior condylar arteriovenous fistula.

Accurate microcatheter placement for anterior condylar arteriovenous fistula (AVF) enables selective transvenous embolization (TVE) and helps to avoid hypoglossal nerve palsy. Anterior condylar AVF has a shunted pouch within the condylar vascular and osseous structures. Detailed anatomical comprehension of the shunted pouch is essential, in addition, we believe that it is important to have a strategy for where in the shunted pouch to start filling with coils. Specifically, we consider that it is important to structurally understand the more upstream location (arterial side) within the shunted pouch (called "shunted pouch entry zone"), guide the microcatheter there, and embolize from that site. Although several studies have discussed the usefulness of intraoperative cone-beam computed tomography (CBCT) for treating anterior condylar AVF, there are no studies which have mentioned the importance of microcatheter position before coil embolization in selective TVE as in this study. Intraoperative localization of the shunted pouch entry zone is often difficult. Herein, the authors report that cone-beam computed tomography (CBCT) can assist accurate microcatheter tip placement at the shunted pouch entry zone before staring embolization. This is the novel application of intraoperative CBCT to treat anterior condylar AVF successfully treated with precise and selective TVE.

Predictors of aneurysm shrinkage after flow diversion treatment for internal carotid artery aneurysms: quantitative volume analysis with MRI.

Background and purpose: Although aneurysm shrinkage often occurs after flow diversion treatment for intracranial aneurysms, no reports have addressed the factors associated with aneurysm shrinkage. Materials and methods: This retrospective single-center study was performed to examine patients with unruptured internal carotid artery aneurysms who were treated using flow diversion and followed up by imaging for at least 12 months. The study outcome was aneurysm shrinkage (volume reduction of ≥10%) 12 months after treatment. Aneurysm volume was quantitatively assessed using the MRIcroGL software. Patient and aneurysm characteristics were statistically analyzed. Results: This study involved 81 patients with 88 aneurysms. At the 6 months, 12 months, and last follow-ups, the proportion of aneurysms that had shrunk was 50, 64, and 65%, respectively. No adjunctive coiling (odds ratio, 56.7; 95% confidence interval, 7.03-457.21; p < 0.001) and aneurysm occlusion (odds ratio, 90.7; 95% confidence interval, 8.32-988.66; p < 0.001) were significantly associated with aneurysm shrinkage. In patients treated by flow diversion with adjunctive coiling, only the volume embolization rate was a factor significantly associated with aneurysm shrinkage (p < 0.001). Its cutoff value was 15.5% according to the receiver operating characteristic curve analysis (area under the curve, 0.87; sensitivity, 0.87; specificity, 0.83). Conclusion: The rate of aneurysm shrinkage after flow diversion increased during the first 12 months after treatment, but not thereafter. No adjunctive coiling and aneurysm occlusion were predictors of aneurysm shrinkage, respectively. If adjunctive coiling is required, a volume embolization rate of ≤15.5% may be suggested for aneurysm regression.

Carotid Micromesh Stent for the Cervical Carotid Artery Dissecting Aneurysm in a Patient with Vascular Eagle Syndrome.

OBJECTIVES: An elongated styloid process may cause vascular Eagle syndrome that includes cervical carotid artery (CCA) dissection with stenosis and aneurysm formation. There are only four reported cases with vascular Eagle syndrome-related CCA dissecting aneurysm treated with carotid artery stenting (CAS). This is the first report of applying a dual-layer nitinol micromesh stent (CASPER) for vascular Eagle syndrome-related CCA dissecting aneurysm. CASE PRESENTATION: A 38-year-old man presented with a sudden onset of aphasia and right hemiplegia. Cerebral angiography demonstrated the left CCA dissecting aneurysm. The superior trunk of the left middle cerebral artery (MCA) was also occluded, and emergent thrombectomy was performed. Computed tomography with angiography (CTA) revealed that a 33 mm-long styloid process compressed the CCA at the aneurysm formation. Three weeks later, a CASPER stent was applied for the CCA aneurysm under the flow reversal system. Immediately after stent placement, blood flow in the aneurysm became stagnant, and postoperative CTA demonstrated regression of the aneurysm. The aneurysm did not recur for 6 months with no styloid process resection. CONCLUSIONS: The dual-layer nitinol micromesh stent (CASPER) was useful to treat vascular Eagle syndrome-related CCA dissecting aneurysm.

Ruptured aneurysm of the posterior inferior cerebellar artery communicating artery: A case report.

We report a case of a ruptured aneurysm of the posterior inferior cerebellar artery (PICA) communicating artery, which is an extremely rare condition, with only 10 other cases reported in the literature. We repaired the aneurysm by clipping combined with occipital artery-PICA (cortical segment) bypass. This surgical method reduces hemodynamic stress and may prevent recurrence or new occurrence of aneurysms in this region. We recommend this method for repair of instances of PICA communicating artery aneurysm rupture.

A Case of Intracerebral Hemorrhage During the Untreated Course of a Benign Dural Arteriovenous Fistula.

BACKGROUND: The natural history of cranial dural arteriovenous fistulas (DAVFs) without cortical venous drainage (i.e., benign DAVF) is considered a potential predictor of a benign clinical course. We report a case of intracerebral hemorrhage due to the conversion from a benign to an aggressive DAVF during 10 months of conservative therapy, which, to the best of our knowledge, is the first reported case of its kind. CASE DESCRIPTION: A woman in her 70s without neurological symptoms was diagnosed with DAVF of the right transverse-sigmoid sinus with Borden type I. After conservative therapy was maintained for 10 months, she had a slight headache without neurological deficits and magnetic resonance imaging revealed intracerebral hemorrhage in the right temporooccipital area. Routine laboratory tests revealed a slight elevation of D-dimer. Emergent digital subtraction angiography demonstrated new cortical venous drainage and stenosis of the venous outlet. The refluxed cortical vein and right transverse-sigmoid sinus including fistulas were occluded with coils via transvenous embolization. She had no neurological deficits in the postoperative state. CONCLUSIONS: Conversion to aggressive DAVF in this patient was probably due to spontaneous stenosis or thrombosis of the venous outflow. Intracranial hemorrhage can occur within 1 year from the detection of benign DAVFs, and elevated D-dimer may predict the conversion to aggressive DAVFs.