Background: Common carotid artery occlusion (CCAO) is rare. Symptomatic lesions are resistant to medical treatment and revascularization are often required, but there is no consensus on the treatment of CCAO. In this paper, two cases of symptomatic CCAO treated by carotid endarterectomy (CEA) with L-shaped ministernotomy, in which the lesions extended to the beginning part of the CCA, are reported. Case Description: Case 1 involved a 74-year-old man who presented with transient left limb numbness and an abnormal right visual field. Cerebrovascular angiography showed that the right CCA was occluded immediately after its origin and blood was supplied from the posterior circulation. CEA was performed with an L-shaped ministernotomy that allowed exposure of the CCA origin with minimal invasion. There were no complications associated with the sternal incision and he was discharged with a modified Rankin Scale (mRS) score of 0. Case 2 involved a 70-year-old man who presented with left half-blindness. Magnetic resonance imaging showed infarction in the right posterior cerebral artery region and neck echo showed CCA pseudo occlusion just before the carotid bulb. A new infarction in the right middle cerebral artery region developed during hospitalization. CEA with partial sternotomy was performed. The patient was rehabilitated with no deterioration of neurological findings and transferred with an mRS score of 3. Conclusion: There were no complications resulting from partial sternotomy in the two cases presented. CEA with partial sternotomy could be an effective treatment option for CCAO in which the internal carotid artery is patent and thrombus extends to the proximal CCA.

We report the characteristics of the platelet aggregation test using Hematracer ZEN (HTZ; DS medical, Tokyo, Japan) during the perioperative period. Methods: Among patients undergoing neuroendovascular treatment (EVT) at our hospital between June 2019 and June 2020, 42 consecutive patients with preoperative dual antiplatelet therapy (DAPT) were included. Oral administration of aspirin (ASA) at 81 mg and clopidogrel (CLP) at 75 mg was started 7 days before treatment (Flow Diverter [FD]: 14 days before). We evaluated platelet aggregation activity the day before treatment (FD: 2 days before) using HTZ. We adjusted the CLP dose according to the platelet aggregation test in each patient. We evaluated the platelet aggregating activity after EVT in patients requiring an intracranial stent or in which CLP was adjusted before EVT. Results: Platelet aggregating activity was able to be evaluated in all patients. In the preoperative examination, the efficacy of CLP was insufficient in one patient (2.4%), optimal medical effects were confirmed in 16 (38.1%), mildly excessive effects were noted in 10 (23.8%), and highly excessive effects were noted in 15 (35.7%). Reassessment was performed postoperatively in 20 patients. We switched CLP to prasugrel in one patient in which the CLP efficacy was considered insufficient in the preoperative evaluation. We reduced the CLP dose in seven patients with marked overdose, and the optimum range was reached in all. We did not adjust the CLP dose in 12 patients judged to have optimal or mildly excessive effects preoperatively, but 4 exhibited highly excessive drug efficacy and required CLP reduction. No postoperative symptomatic cerebral infarction or intracranial hemorrhage was observed (mean observation period: 11 months, range: 4-16 months). Conclusion: The platelet aggregation test using HTZ was simple and inexpensive, and was useful for adjusting the dose of antiplatelet drugs, but its utility should be evaluated in more patients. Keywords▶ neuroendovascular therapy, platelet aggregation test, clopidogrel, Hematracer ZEN, flow diverter stent This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives International License.

Cyst formation is a well-known complication of gamma knife surgery for the treatment of arteriovenous malformation (AVM). Surgical treatment for cysts is widely performed, but there is no common procedure for the surgery. We report a case of cyst recurrence after partial resection of a nodule that exhibited enhancement on magnetic resonance imaging (MRI). A 44-year-old man underwent surgery for a cyst that formed after gamma knife surgery for an AVM performed 5 years earlier.MRI performed after the surgery revealed an enhancing nodule. Six months later, a cyst formed around the nodule and grew steadily. Because of the cyst, the patient had a seizure. We decided to perform an operation to resect the cyst and nodule. After the second operation, enhanced MRI showed there was no remaining nodule. The patient had no recurrence until 15 months after surgery. The findings from this case suggest that total resection of the enhancing nodules must be performed during surgery for cysts that form after gamma knife surgery for AVM.

Background: It is not well-known that contralateral vertebral artery dissecting aneurysms (VADA) may be newly revealed after parental artery occlusion for unilateral VADA. However, the optimal treatment strategies and perioperative management have not been established. In this report, we present the case of a patient who required reconstructive embolization in the subacute stage for contralateral VADA developed after endovascular internal trapping of the ruptured VADA. Case Description: A 61-year-old man developed subsequent disturbance of consciousness. Head CT showed a diffuse and symmetrical SAH. 3DCT revealed a fusiform aneurysm of the left intracranial vertebral artery with bleb formation. We performed emergency endovascular parent artery occlusion of the left vertebral artery. A digital subtraction angiography on postoperative day 16 showed continued occlusion of the left VA, and a fusiform aneurysm was noted at the right VA. We performed reconstructive embolization and the patient eventually recovered with minimal persistent symptoms. Conclusion: Since the outcomes of contralateral VAD complicated by infarction or hemorrhage are poor, and most cases develop within 7–14 days after endovascular internal trapping for unilateral VAD, performing bilateral radiographic reinspection within this time frame is recommended for early detection and preventive treatment of possible contralateral VADs.

A case of cerebral hemorrhage due to developmental venous anomaly (DVA) occurred secondly to sinus thrombosis