Percutaneous transluminal angioplasty for vertebral artery origin stenosis under the flow-reversal protection using Mo.MA™ Ultra: A technical case report.

Background: Vertebral artery origin stenosis (VAOS) is a major cause of ischemic stroke of the posterior circulation. Aggressive medical treatment using dual antiplatelet therapy is the most common treatment approach to symptomatic VAOS; however, the effectiveness of endovascular treatment (EVT) for VAOS has recently been reported. Here, we report a case of VAOS treated with percutaneous transluminal angioplasty (PTA) under flow reversal protection using Mo.MA™ Ultra. Case Description: The patient was a 78-year-old man. He underwent mechanical thrombectomy for acute right posterior cerebral artery occlusion, and recanalization was achieved. Subsequently, artery-to-artery (A-to-A) embolism caused by the right VAOS was revealed as the etiology. PTA under the flow-reversal protection using Mo.MA™ Ultra was performed electively, and the VAOS and antegrade flow of the right vertebral artery (VA) improved. Conclusion: In EVT for symptomatic VAOS, lesion cross for distal protection device placement is considered to create a high risk of distal embolism due to the anatomic and clinicopathological characteristics of VAOS lesions, especially in A-to-A embolism cases. The flow-reversal protection using Mo.MA™ Ultra can be performed with EVT to prevent distal embolism with lesion cross by retrograde flow of the VA. This method is feasible, especially for cases in which antegrade flow to the basilar artery through the developed contralateral VA is anticipated during the Mo.MA™ Ultra protection.

Primary results of mechanical thrombectomy for acute ischemic stroke: The K-NET registry in the Japanese metropolitan area.

BACKGROUND: Endovascular treatment (EVT) for acute large vessel occlusion has proven to be effective in randomized controlled trials. We conducted a prospective cohort study to evaluate the real-world efficacy of EVT in a metropolitan area with a large number of comprehensive stroke centers and to compare it with the results of other registries and randomized controlled trials (RCTs). METHODS: We analyzed the Kanagawa Intravenous and Endovascular Treatment of Acute Ischemic Stroke registry, a prospective, multicenter observational study of patients treated by EVT and/or intravenous tissue-type plasminogen activator (tPA). Of the 2488 patients enrolled from January 2018 to June 2020, 1764 patients treated with EVT were included. The primary outcome was a good outcome, which was defined as a modified Rankin Scale (mRS) of 0-2 at 90 days. Secondary analysis included predicting a good outcome using multivariate logistic regression analysis. RESULTS: The median age was 77 years, and the median National Institute of Health Stroke Scale (NIHSS) score was 18. Pretreatment mRS score 0-2 was 87%, and direct transport was 92%. The rate of occlusion in anterior circulation was 90.3%. Successful recanalization was observed in 88.7%. The median time from onset to recanalization was 193 min. Good outcomes at 90 days were 43.3% in anterior circulation and 41.9% in posterior circulation. Overall mortality was 12.6%. Significant predictors for a good outcome were as follows: age, male, direct transfer, NIHSS score, Alberta Stroke Program Early Computed Tomography Score, intravenous tPA, and successful recanalization. CONCLUSION: EVT in routine clinical use in a metropolitan area showed comparable good outcomes and lower mortality compared to previous studies, despite the high proportion of patients with older age, pretreatment mRS score of >2, posterior circulation occlusion, and higher NIHSS. Those results may have been associated with more direct transport and faster onset-to-recanalization times.

Stenting Combined with Coil Embolization of a Dissecting Aneurysm after Traumatic Vertebral Artery Injury.

Objective: We report a case of dissecting aneurysm developed after traumatic vertebral artery dissection (VAD) treated by stenting combined with coil embolization. Case Presentation: A 47-year-old man was injured in a fall and presented with left VAD associated with central spinal injury due to C2 fracture. One week after admission, magnetic resonance imaging (MRI) demonstrated contralateral VAD with a dissecting aneurysm. Due to bilateral VAD, we employed coil embolization and stenting for the dissecting aneurysm to prevent rupture and embolic events, and to maintain the patency of the dominant right VA. There were no complications during the perioperative period. The follow-up angiogram 6 months after embolization confirmed obliteration of the dissecting aneurysm and patency of the parent artery. Conclusion: Stenting combined with coil embolization is an effective treatment for traumatic VAD with a dissecting aneurysm.

Usefulness of preoperative cone beam computed tomography and intraoperative digital subtraction angiography for dural arteriovenous fistula at craniocervical junction: Technical case report.

BACKGROUND: Direct surgery is commonly selected for the treatment of cranio-cervical junction dural arteriovenous fistula and its outcome is more satisfactory than that of embolization. Intraoperative treatment evaluation is relatively easy in embolization, whereas in direct surgery it can be difficult. CASE DESCRIPTION: A 67-year-old male suffered a subarachnoid hemorrhage. On three-dimensional (3D) images of preoperational cone-beam computed tomography (CBCT), the structure of the draining vein was depicted in detail along with the surrounding bone structures. The radial artery penetrated the dura mater, and it was found that there were two veins derived from the radiculospinal vein; one was the anterior radicular vein descending toward the dorsal side (the shallow layer of the surgical field) and the other was the anterior spinal medullary vein ascending toward the ventral side (the deep layer of the surgical field) and flowing out to the anterior spinal vein. CONCLUSION: Without detailed assessments with preoperative CBCT, the surgery might have been done with dissection of only the anterior radicular vein in the shallow layers. For identification of the draining vein located deep in the surgical field, such as the cranio-cervical junction, careful assessments using 3D CBCT images are important.

A Case of Multiple Cerebral Infarction Preceding Acute Exacerbation of Idiopathic Thrombocytopenic Purpura.

BACKGROUND: Although it was suggested that idiopathic thromobocytopenic purpura (ITP) can be a paradoxical cause of cerebral infarction, previous reports indicate that cerebral infarction associated with ITP occurs when thrombocytopenia is already evident at the onset of cerebral infarction. CASE REPORT: We report a case of multiple cerebral infarction that preceded acute exacerbation of ITP. An 80-year-old woman with a history of ITP presented with tetraplegia, and brain magnetic resonance imaging revealed multiple infarction in bilateral cerebral and cerebellar hemispheres. For ITP, she was treated with oral prednisolone and subcutaneous injection of thrombopoietin receptor agonists. Her platelet count was within the normal range at the onset of cerebral infarction. Medical work-up did not reveal the obvious causes of her multiple cerebral infarction. On day 10 of hospitalization, she showed melena and oral hemorrhage and her platelet count markedly decreased. Her platelet-associated IgG level was elevated and a diagnosis of acute exacerbation of ITP was made. She was treated with intravenous immunoglobulin and her platelet count increased moderately. However, her neurological symptoms and cerebral infarction on magnetic resonance imaging deteriorated accompanied by hemorrhagic transformation. Finally, she died of respiratory failure. CONCLUSIONS: Our case suggests that thrombophilia accompanied by ITP can precede actual exacerbation of ITP and we have to consider ITP as a possible cause of multiple cerebral infarction, even when the platelet count is within the normal range at the onset of cerebral infarction.

A case of a cerebral cavernous malformation of the third ventricle that caused the syndrome of inappropriate secretion of antidiuretic hormone.

BACKGROUND: Cerebral cavernous malformations (CCMs, also known as cavernous hemanigiomas) of the third ventricle are uncommon. Here, we present a rare case of a CCM that caused the syndrome of inappropriate secretion of antidiuretic hormone (SIADH). CASE DESCRIPTION: A 68-year-old man presented with acute-onset cognitive and memory disturbance. Endocrinological examinations revealed hyponatremia due to SIADH. Computed tomography indicated a high-density mass in the third ventricle that caused left unilateral hydrocephalus due to obstruction of the foramen Monroe. On magnetic resonance imaging, the mass showed high intensity in both T1 and T2-weighted images and low intensity in susceptibility-weighted images, suggesting subacute intralesional hemorrhage. We completely excised the mass via a basal interhemispheric translamina terminalis approach. Intraoperatively, the mass adhered tightly to the left hypothalamus, which was supposed to the origin and was well circumscribed from the surroundings. The histopathological diagnosis was CCM, and his SIADH improved after the operation. CONCLUSION: We presented a rare case of a CCM in the third ventricle that caused SIADH, which improved after complete excision of the mass via a basal interhemispheric translamina terminalis approach.

Removal of a malignant cystic brain tumor utilizing pyoktanin blue and fibrin glue: Technical note.

BACKGROUND: The leakage of cystic fluid during metastatic cystic brain tumor resection may cause tumor dissemination. When the cyst wall is thin, excision without removing the wall is often difficult. METHODS: We were able to perform an en bloc resection of a cystic malignant brain tumor after aspirating the cystic fluid, injecting pyoktanin blue into the cyst to stain the cyst walls, and solidifying the empty cyst cavity by filling it with fibrin glue. RESULTS: Pyoktanin blue readily stained the thin cystic walls and enabled visualization of mural damage. Solidification of the tumor made it easier to grasp and facilitated the dissection of tumor margins. CONCLUSIONS: This method has the potential to become a useful technique for the resection of malignant cystic brain tumors.

[A Ruptured Vertebral Artery Dissecting Aneurysm Involving the Anterior Spinal Artery:A Case Report].

A 50-year-old woman presented with a subarachnoid hemorrhage caused by a ruptured vertebral artery dissecting aneurysm(VADA)involving the anterior spinal artery(ASA). The ASA branched at the proximal component of the dissecting aneurysm. The rupture point was presumed to be the distal region of the dissecting aneurysm. We performed coil embolization of the distal part only in order to prevent rebleeding and preserve the ASA. The patient showed no neurological deficits. Six months after the procedure, an angiogram demonstrated occlusion of a distal portion of the right vertebral artery. However, the ASA was still patent. No rebleeding occurred, and the patient has remained neurologically symptom-free for 3 years from the treatment. ASA-involved VADAs are extremely rare. Treatment strategy is difficult because there are no options for bypass surgery and occlusion of the ASA may lead to quadriplegia unless there is collateral flow to the ASA. Although the outcome of the patient was good with partial coil embolization in this case, the treatment strategy should be carefully considered for ASA-involved VADAs.

Reappraisal of primary balloon angioplasty without stenting for patients with symptomatic middle cerebral artery stenosis.

There is a controversy regarding the safety and efficacy of intracranial stenting. We describe our experience with primary balloon angioplasty without stenting for symptomatic middle cerebral artery (MCA) stenosis. All patients who underwent balloon angioplasty without stenting for MCA stenosis between 1996 and 2010 were retrospectively reviewed. We evaluated technical success rates, degrees of stenosis, and stroke or death within 30 days. Among patients who were followed-up for > 1 year we evaluated latest functional outcomes, stroke recurrence at 1 year, and restenosis. In total 45/47 patients (95.7%) were successfully treated. Average pre- and postprocedure stenosis rates were 79.9% and 39.5%, respectively. Three neurological complications occurred within 30 days: one thromboembolism during the procedure; one lacunar infarction; and one fatal intraparenchymal hemorrhage after the procedure. Stroke or death rate within 30 days was 6.4%. Thirty-three patients were available for follow-up analysis with a mean period of 51.5 months. The combined rate of stroke or death within 30 days and ipsilateral ischemic stroke of the followed-up patients within 1 year beyond 30 days was 9.4%. Restenosis was observed in 26.9% of patients and all remained asymptomatic. In our retrospective series, balloon angioplasty without stenting was a safe, effective modality for symptomatic MCA stenosis. For patients refractory to medical therapy, primary balloon angioplasty may offer a better supplemental treatment option.

Iatrogenic pneumothorax after ventriculoperitoneal shunt: an unusual complication and a review of the literature.

A patient received a ventriculoperitoneal shunt operation for hydrocephalus after subarachnoid hemorrhage. Postoperative computed tomography incidentally revealed asymptomatic pneumothorax caused by a shunt tube passing through the thoracic space. The patient was observed without removal of the tube or chest drainage, with the expectation of spontaneous recovery. However, the pneumothorax was not cured, and chest drainage was performed and eventually resolved the pneumothorax. The ventriculoperitoneal shunt worked well, and the patient recovered from consciousness disturbance. We discuss treatment strategies for this rare complication and how to avoid it. A review of the literature suggests that female or obese patients may be associated with this complication.

Triple antiplatelet therapy with addition of cilostazol to aspirin and clopidogrel for Y-stent-assisted coil embolization of cerebral aneurysms.

BACKGROUND: Dual antiplatelet therapy for stent-assisted coiling of cerebral aneurysms is essential to prevent thromboembolic complications. There is concern that Y-stent-assisted coiling may increase thromboembolic complications compared with coiling with a single stent. Several reports have demonstrated that cilostazol may improve clopidogrel responsiveness. We investigated whether triple antiplatelet therapy with addition of cilostazol to aspirin plus clopidogrel for Y-stents can prevent thromboembolic events. METHODS: Between July 2010 and October 2012, we treated 40 consecutive aneurysms with coil embolization using Enterprise stents. At the peri-procedural period, dual antiplatelet agents (100 mg aspirin and 75 mg clopidogrel) were used for the single stent group (n = 36), and triple antiplatelet agents (addition of 200 mg cilostazol) were used for the Y-stent group (n = 4). We evaluated post-operative diffusion-weighted imaging (DWI) and any complications. We assessed the following for statistical analysis: age, sex, aneurysm location, shape, and size, neck size, size of parent vessels, and stent length. RESULTS: We found two neurological peri-procedural complications: one transient ischemic attack and one infarction. Both complications belonged to the Y-stent group, which was a significant factor of thromboembolic events (P = 0.008). There were no other significant factors related to neurological complications or positive DWI. For subgroup analysis of the single stent group, stent length was significantly longer in positive DWI than negative DWI (P = 0.04). In the follow-up period of 20 ± 8.6 months, there were no symptomatic late complications in any patients. CONCLUSIONS: Although the number of patients in the Y-stent group is small, this group had a significantly higher risk of thromboembolic complications. While our protocol of a routine dose of dual antiplatelet therapy may be sufficient for single stent therapy, our protocol of a routine dose of triple antiplatelet therapy for Y-stents may not prevent thromboembolic events. This suggests that evaluation of platelet function may be essential, especially for Y-stents.

Changes in wall shear stress magnitude after aneurysm rupture.

Computational fluid dynamics (CFD) studies on cerebral aneurysms have attempted to identify surrogate hemodynamic parameters to predict rupture risk. We present a case of bilateral mirror image aneurysms, one of which ruptured soon after imaging. Wall shear stress values of the ruptured aneurysm changed by 20-30% after rupture because of change in the aneurysm shape. Findings from our case suggest that CFD studies comparing unruptured and ruptured aneurysms may not yield valid estimation on aneurysm rupture risk because of changes in aneurysm shape after rupture. Changes in aneurysm shape after rupture should be considered in CFD research.

Semiquantitative analysis using thallium-201 SPECT for differential diagnosis between tumor recurrence and radiation necrosis after gamma knife surgery for malignant brain tumors.

PURPOSE: Semiquantitative analysis of thallium-201 chloride single photon emission computed tomography (201Tl SPECT) was evaluated for the discrimination between recurrent brain tumor and delayed radiation necrosis after gamma knife surgery (GKS) for metastatic brain tumors and high-grade gliomas. METHODS AND MATERIALS: The medical records were reviewed of 75 patients, including 48 patients with metastatic brain tumor and 27 patients with high-grade glioma who underwent GKS in our institution, and had suspected tumor recurrence or radiation necrosis on follow-up neuroimaging and deteriorating clinical status after GKS. Analysis of 201Tl SPECT data used the early ratio (ER) and the delayed ratio (DR) calculated as tumor/normal average counts on the early and delayed images, and the retention index (RI) as the ratio of DR to ER. RESULTS: A total of 107 tumors were analyzed with 201Tl SPECT. Nineteen lesions were removed surgically and histological diagnoses established, and the other lesions were evaluated with follow-up clinical and neuroimaging examinations after GKS. The final diagnosis was considered to be recurrent tumor in 65 lesions and radiation necrosis in 42 lesions. Semiquantitative analysis demonstrated significant differences in DR (P=.002) and RI (P<.0001), but not in ER (P=.372), between the tumor recurrence and radiation necrosis groups, and no significant differences between metastatic brain tumors and high-grade gliomas in all indices (P=.926 for ER, P=.263 for DR, and P=.826 for RI). Receiver operating characteristics analysis indicated that RI was the most informative index with the optimum threshold of 0.775, which provided 82.8% sensitivity, 83.7% specificity, and 82.8% accuracy. CONCLUSIONS: Semiquantitative analysis of 201Tl SPECT provides useful information for the differentiation between tumor recurrence and radiation necrosis in metastatic brain tumors and high-grade gliomas after GKS, and the RI may be the most valuable index for this purpose.