Aberrant right subclavian artery with right type 1 proatlantal artery and segmental dysplasia of the right internal carotid artery: a case report.

PURPOSE: We present a case of an aberrant right subclavian artery (ARSA) with extremely rare vascular anomalies. CASE REPORT: A 69-year-old woman was suspected to have right internal carotid artery (ICA) stenosis. Computed tomography angiography demonstrated an ARSA and hypoplasia of the right ICA. The proximal segment of the right vertebral artery (VA) was aplasia, and a right type 1 proatlantal artery (PA) arose from the right common carotid artery. Cerebral angiography demonstrated segmental dysplasia of the right ICA. The ascending intrapetrous segment and the ascending foramen lacerum-horizontal intracavernous segment of the right ICA demonstrated hypoplasia. The collateral pathways promoted reconstitution of each of the distal segments. Left internal carotid angiography demonstrated anterior communicating artery aneurysm and sufficient cross flow to the contralateral middle cerebral artery via the AcomA. DISCUSSION: A type 1 PA with an ARSA may result in the regression of the right dorsal aorta with persistence of the first cervical intersegmental artery. Although there are few findings of a relationship between an ARSA and intracranial artery anomalies, a developmental error of the right dorsal aorta may cause such complex vascular anomalies. CONCLUSION: Knowledge of anatomical variations in patients with ARSA is useful when performing angiography or endovascular therapy, as well as during clinical follow-up.

[Treatment Strategy and Results of Carotid Endarterectomy in Chronic Renal Failure Patients].

INTRODUCTION: The number of patients receiving chronic dialysis treatment in Japan currently exceeds 300,000 people. Few reports have described carotid endarterectomy(CEA)for chronic renal failure patients because of the unacceptable rate of perioperative stroke and other morbidities. A strategy for and treatment results of CEA for chronic renal failure patients in our hospital are described herein. METHODS: The present study included 6 patients who underwent CEA while receiving dialysis treatment between April 2011 and November 2014. RESULTS: Dialysis treatment was initiated due to diabetes in 4 patients and renal sclerosis in 2 patients. All the patients were men, with a mean age of 74.0 years. Two patients were symptomatic, and four were asymptomatic. In all the patients, heart vascular lesions and arteriosclerosis risk factors were present. Postoperatively, pneumonia transient cranial neuropathy, heart failure, and pneumonia in 1 case required extensive treatment. However, by the time of discharge from hospital, no cases had deteriorated compared with their pre-CEA state. The modified Rankin scale score on discharge was 0-2 for all the patients. CONCLUSION: CEA can be performed safely in patients receiving dialysis, but further operative procedures and careful postoperative management are likely to be needed for patients with CEA who are receiving dialysis.

Cerebral hyperperfusion syndrome after endovascular reperfusion therapy for medium vessel occlusion: A case report.

Cerebral hyperperfusion syndrome is a rare but serious complication after revascularization procedures for cerebrovascular diseases. Cerebral hyperperfusion syndrome can develop after treatment of acute ischemic stroke, including intravenous thrombolysis and endovascular treatment of large vessel occlusion. However, to the best of our knowledge, there are no previous reports describing cerebral hyperperfusion syndrome after endovascular treatment of medium vessel occlusion (eg, anterior cerebral artery A2/3 segment). We report a case of cerebral hyperperfusion syndrome after endovascular reperfusion therapy for medium vessel occlusion. A 70-year-old woman with a history of hypertension and dyslipidemia was transferred by ambulance to our hospital because of immobility and slurred speech. She had mild right lower extremity paralysis, and her symptoms appeared improved compared with onset. She was diagnosed with cerebral infarction in the left frontal lobe. After hospitalization, her neurological symptoms worsened and she was referred to our department. We performed endovascular reperfusion therapy for left anterior cerebral artery A2 occlusion. Recanalization was achieved with residual stenosis. Despite the lack of complications associated with the procedure, the patient had prolonged disorientation, severe hemiplegia, and aphasia. Arterial spin labeling demonstrated hyperperfusion in the left anterior cerebral artery area. The symptoms gradually improved under strict blood pressure control. This report provides evidence that cerebral hyperperfusion syndrome can occur even after endovascular treatment for medium vessel occlusion. Arterial spin labeling was useful in detecting hyperperfusion.

Endovascular treatment of acute atherothrombotic internal carotid artery occlusion associated with persistent primitive hypoglossal artery.

Persistent primitive hypoglossal artery is a relatively rare anatomical variation and a type of persistent carotid-basilar anastomosis. Acute internal carotid artery occlusion associated with persistent primitive hypoglossal artery is rare, and atherothrombotic occlusion is extremely rare. We present a case of acute atherothrombotic internal carotid artery occlusion associated with persistent primitive hypoglossal artery that was successfully treated by endovascular treatment. A 70-year-old male with a history of left internal carotid artery stenosis was transferred to our hospital by ambulance because of abnormal behaviors and aphasia. He was diagnosed with cerebral infarction and left internal carotid artery occlusion. Left carotid angiography revealed the persistent primitive hypoglossal artery arising from the cervical internal carotid artery and complete internal carotid artery occlusion distal to the origin of the persistent primitive hypoglossal artery. Therefore, we performed endovascular treatment. Mechanical thrombectomy was performed under minimal flow arrest with consideration of brain ischemia causing coma. After additional balloon angioplasty, recanalization was achieved, and the patient's symptoms improved. During the 1.5-year follow-up period, no recurrence or restenosis was observed. This report provides evidence that atherosclerotic internal carotid artery stenosis associated with persistent primitive hypoglossal artery can occur even distal to the origin of the persistent primitive hypoglossal artery and that the lesion may become acutely occluded, leading to acute stroke. Endovascular treatment considering brain ischemia was effective in this case.

Mechanical thrombectomy for middle cerebral artery occlusion caused by intracranial internal carotid artery stenosis: A case report.

Tandem internal carotid artery (ICA)/middle cerebral artery (MCA) occlusions are occasionally observed in patients with acute ischemic stroke. Most of them are caused by lesions at the origin of the ICA. In cases of intracranial ICA stenosis, the formation of a large thrombus causing MCA occlusion is extremely rare. Herein We report a case of acute MCA occlusion caused by intracranial ICA stenosis. A 62-year-old female presented with aphasia, right-side weakness, and a National Institute of Health Stroke Scale (NIHSS) score of 5. Magnetic resonance imaging (MRI) showed early ischemic infarction at the precentral gyrus. Left ICA and M1 occlusion were suspected on magnetic resonance angiography. However, the patient had complained of right-side numbness 6 days before the onset. Hence the stroke was assumed to have progressed slowly, and acute occlusion of the left ICA was eliminated as a suspected diagnosis. After admission, the symptoms worsened. MRI showed enlargement of the cerebral infarction. Computed tomography angiography showed complete occlusion of the left M1 and recanalization of the left ICA with severe stenosis of the petrous portion. The etiology of the MCA occlusion was determined to be atherothromboembolism. Percutaneous transluminal angioplasty (PTA) was performed for ICA stenosis, followed by mechanical thrombectomy (MT) for the MCA occlusion. Recanalization of the MCA was achieved. After Seven days, the NIHSS score reduced from a pre-MT assessment of 17-2. PTA followed by MT was safe and effective for treating MCA occlusion caused by intracranial ICA stenosis.

Bilateral vertebral artery dissection extending to the left posterior cerebral artery: A case report.

Intracranial artery dissection accounts for a small percentage (1%-2%) of all ischemic strokes. Vertebral artery dissection sometimes extends to the basilar artery but very rarely to the posterior cerebral artery. We report a case of bilateral vertebral artery dissection extending to the left posterior cerebral artery with the characteristic distribution of intramural hematoma. A 51-year-old woman presented with right hemiparesis and dysarthria 3 days after sudden neck pain. Magnetic resonance imaging on admission revealed infarcts in the left thalamus and temporo-occipital lobe and findings suggestive of bilateral vertebral artery dissection. No infarct was detected in the brainstem. The patient was treated conservatively. Initially, we suspected that infarction in the left posterior cerebral artery territory had been caused by artery-to-artery embolism from the dissected vertebral arteries. However, T1-weighted imaging on day 15 of admission revealed intramural hematoma extending from the left vertebral artery to the left posterior cerebral artery. Therefore, we diagnosed bilateral vertebral artery dissection extending to the basilar artery and the left posterior cerebral artery. The patient's symptoms subsequently improved with conservative treatment, and she was discharged with a modified Rankin Scale score of 1 on day 62 of admission. In this case, intramural hematoma of the basilar artery was found in the anterior vessel wall. Brainstem infarction is less likely when intramural hematoma is located in the anterior vessel wall of the basilar artery in vertebrobasilar artery dissection. T1-weighted imaging is useful for the diagnosis of this rare condition and can predict potentially impaired branches and possible symptoms.

Acute middle cerebral artery occlusion caused by spontaneous thrombosis of a small internal carotid artery aneurysm: illustrative case.

BACKGROUND: Spontaneous thrombosis of a saccular, unruptured, intracranial aneurysm is rare in nongiant aneurysms. Herein, the authors present a case of acute middle cerebral artery occlusion (MCO) caused by spontaneous thrombus of a small internal carotid artery (ICA) aneurysm. OBSERVATIONS: A 68-year-old woman presented with increased somnolence, right-sided hemiplegia, hemispatial neglect, and total aphagia. Left MCO and a small left ICA aneurysm were suspected based on magnetic resonance angiography (MRA). The authors detected early ischemic lesions from diffusion-weighted imaging (DWI). The DWI-Alberta Stroke Program Early Computed Tomography Score was 6. T2*-weighted imaging (T2*WI) showed a thrombus, the so-called susceptibility vessel sign, at the left MCO site. Another suspected thrombus was also found in the ipsilateral ICA aneurysm. The authors treated acute phase MCO with mechanical thrombectomy (MT), after which secondary stroke prophylaxis consisting of warfarin potassium was started. Since follow-up T2*WI showed the thrombus had disappeared from the left ICA aneurysm and the whole aneurysm was clarified by MRA, coil embolization was performed. After coil embolization, there was no ischemic recurrence. LESSONS: Aneurysms are infrequently found proximal to occlusion sites during MT. If the proximal aneurysm is a potential embolic source, treatment of the said aneurysm may prevent stroke.

Mechanical Thrombectomy Making Practical Use of an Aspiration Catheter While Selecting the Retrieval Technique during the Procedure.

Objective: To report the outcomes of thrombectomy for arterial occlusion involving the major arteries of the cerebral anterior circulation when an aspiration catheter (AC) was used in all cases, with the retrieval technique chosen during the procedure. Methods: Of the 126 patients who underwent endovascular thrombectomy during the 2-year period of 2018-2019, the study subjects were 102 patients with arterial occlusion involving the major arteries of the cerebral anterior circulation. Patients were divided into two groups depending on when the procedure was performed. In the earlier group (January 2018-March 2019), treatment was performed using only a stent retriever (SR), whereas an AC was used for all cases in the later group (April-December 2019). Outcomes between groups were retrospectively compared. In the later group, the treatment strategy was to use the SR in combination with the AC (combined technique) for retrieval if the microcatheter reached the distal side of the occlusion site without difficulty. If the microcatheter did not easily reach the distal side, we did not stick to penetrating the occlusion site, and contact aspiration was performed. Results: Thrombolysis in cerebral infarction (TICI) grade 2b-3 was achieved in 85% of patients in the earlier group and 95% in the later group. TICI grade 3 was achieved in 52% of the earlier group and 54% of the later group, showing no significant difference. TICI grade 2b-3 was achieved at first pass in 46% of patients in the earlier group, significantly lower than the 71% in the later group (P = 0.013). The mean number of passes decreased significantly from 1.84 in the earlier group to 1.32 in the later group (P = 0.002). Conclusion: Using an AC from the start, and using a combined technique when the microcatheter reached the distal side of the occlusion site, the frequency of first-pass TICI grade 2b-3 increased, and the mean number of passes decreased in comparison with the SR-alone group.

The endothelialization on carotid web treated with dual layer stent placement: a case report.

Carotid webs are known to cause acute ischemic stroke in younger adults and have a high recurrence rate. Herein, we report a case of a symptomatic carotid web in a 51-year-old man who was transferred to our hospital after developing consciousness disturbance and left hemiparesis. He was diagnosed with right middle cerebral artery occlusion and underwent mechanical thrombectomy. Because his carotid web was the likely embolic source, we performed carotid artery stenting using a dual-layer stent to crimp the vessel wall and secure closure of the web pocket. Follow-up angiography was performed at 3 weeks after stenting, and endothelialization on the web pocket was confirmed. The high scaffolding effect of the dual layer stent may promote the endothelialization on the carotid web.

Mechanical thrombectomy for acute fetal posterior cerebral artery occlusion with a hidden unruptured cerebral aneurysm: illustrative case.

BACKGROUND: Fetal posterior cerebral artery occlusion is rare and often presents with severe neurological symptoms. Although acute recanalization therapy is commonly used for cerebral vessel occlusion, unruptured cerebral aneurysms can be hidden distal to the occluded vessels. OBSERVATIONS: An 87-year-old man presented with consciousness disturbance and right hemiparesis. The authors diagnosed left fetal posterior cerebral artery occlusion and performed mechanical thrombectomy. A stent retriever was deployed from the middle cerebral artery M1 segment across the mural thrombus of the internal carotid artery. After the first pass, the fetal posterior cerebral artery remained occluded, with confirmation of a contrast effect around the thrombus. Because the anatomical course of the fetal posterior cerebral artery was unidentified, the procedure was stopped. At 1-week recovery, magnetic resonance imaging revealed complete recanalization and a fetal posterior cerebral artery aneurysm hidden within the occluded site. Blood flow was directed to the aneurysm, and the thrombus within the aneurysm simultaneously occluded the fetal posterior cerebral artery. LESSONS: To avoid critical complications following mechanical thrombectomy for fetal posterior cerebral artery occlusion, hidden aneurysms should be suspected when a "fried egg-like" contrast effect is observed around the thrombus.

A Case of Internal Carotid Artery Occlusion Caused by En Bloc Distal Embolization of Carotid Free-Floating Thrombus Treated by Mechanical Thrombectomy.

Objective: We report a case of internal carotid artery (ICA) occlusion caused by en bloc distal embolization of carotid free-floating thrombus (FFT) treated by mechanical thrombectomy. Case Presentation: A 57-year-old woman was brought to our hospital with dysarthria, right hemiparesis, and motor aphasia. MRI and MRA revealed acute infarction due to middle cerebral artery occlusion. Carotid ultrasonography demonstrated a pedunculated mobile plaque in the left ICA. We diagnosed embolic infarction due to the carotid FFT and started medical treatment. However, on the second hospital day, the carotid FFT detached from the arterial wall en bloc, resulting in left ICA occlusion. The occluded ICA was successfully recanalized by mechanical thrombectomy. Conclusion: FFT is associated with a high risk of embolic ischemic stroke and the primary treatment strategy must be carefully considered.

Target Embolization of Dilated Post-PICA Segment for Ruptured PICA-Involved Type Vertebral Artery Dissecting Aneurysm.

Objective: In parent artery occlusion (PAO) for ruptured vertebral artery dissecting aneurysms (RVADA), target embolization using coils in a short segment to occlude only the vasodilated area containing the rupture point is selected as a first-choice procedure at our institute. We focused on RVADA involving the posterior inferior cerebellar artery (PICA) and evaluated the treatment results. Methods: This study consisted of eight cases with RVADA involving the PICA which were treated between October 2007 and January 2020. Based on radiological findings such as the bleb, the rupture points were located at the affected vertebral artery (VA) distal to PICA in all cases. Target embolization, by which only coiling at the dilated segment distal to the VA was performed. We aimed to preserve blood flow to the PICA. The incidence and extent of medullary infarctions, and neurological outcome were retrospectively assessed. Results: Regarding the diameter of bilateral VA, there were no differences in six cases while the affected VA with RVADA were larger in the remaining two cases. PICA was preserved in all cases but one in which occlusion of complementary PICA was observed. Postoperative medullary infarction was not noted. There was no rebleeding during the follow-up period. However, recanalization of the VA was observed in four cases and additional coil embolization was performed. All patients were discharged with a good outcome (modified Rankin Scale [mRS] 0; seven patients, mRS 2; one patient). Conclusion: Target embolization preserving the PICA in PICA-involved type RVADA was considered to be an effective treatment method for cases whose rupture point was located in the VA distal to PICA orifice.

Results of Therapy Using Oral Anticoagulants in the Acute Phase after Mechanical Thrombectomy.

Objective: The usage of oral anticoagulants (OACs) in the acute phase of cerebral infarction has increased, but the optimal timing for starting OACs after mechanical thrombectomy (MT) is unclear. We report the usage of OACs after MT at our hospital and evaluated the outcomes. Methods: OACs were selected as secondary preventive drugs for 64 patients who underwent MT for anterior circulatory embolism between July 2016 and January 2019. Of the 64 patients, 28 and 36 received direct oral anticoagulants (DOACs) and warfarin (Wf), respectively. We compared the frequency of intracranial hemorrhage in the acute phase and that of recurrent cerebral infarction within 30 days. Results: The median diffusion-weighted imaging-Alberta Stroke Program Early Computed Tomography Scores + white matter (DWI-ASPECTS + W) score at admission was 7.5 (IQR 6-9)/8 (IQR, 6-9) in the DOACs group/Wf group. The rate of recanalization with modified thrombolysis in cerebral infarction (TICI) ≥2B by MT was 89.3/80.6%. In patients with subarachnoid hemorrhage (SAH) associated with MT and patients with hemorrhagic transformation (HT) on MRI the next day, administration was started after hemostasis. The median timing of the first anticoagulant administration was 3 (IQR, 2-4)/2 (IQR, 1-4) days. In the case of no HT the next day, the rate of new HT after 1 week was 7.1%/29.1%. In the case of HT the next day, the rate of HT deterioration the next day was 7.1%/16.6%. The percentage of symptomatic bleeding was 0%/2.8%. The percentage of recurrent cerebral infarction within 30 days was 0%/2.8%. Conclusion: OACs in the acute phase after MT can be safely used and are expected to be effective at preventing recurrence.