Successful Recanalization by Intravenous Thrombolysis in a Patient With Calcified Cerebral Emboli With Major Vessel Occlusion: A Case Report.

A 69-year-old man, with a history of left superficial temporal artery-middle cerebral artery bypass due to cerebral infarction by left internal carotid artery occlusion, was hospitalized with acute right hemispatial neglect and left hemiparesis. Diffusion-weighted imaging showed a high-intensity lesion in the right insular cortex. Although there seemed to be no arterial occlusion in magnetic resonance angiography (MRA), non-contrast computed tomography (CT) on admission showed calcification in the right Sylvian fissure. As hyperacute ischemic stroke within 4.5 hours after onset, we used an intravenous recombinant tissue plasminogen activator, and his symptoms improved. Follow-up MRA revealed recanalization of the right M2 branches with distal migration of calcification. Although calcification was identified on non-contrast CT in the initial assessment, the diagnosis of middle cerebral artery occlusion was missed. Therefore, arterial occlusion should be considered when calcification is observed in the brain sulcus. This case also illustrated that intravenous thrombolysis may be effective even in calcified cerebral emboli with major vessel occlusion.

Amyloid accumulation in cases of suspected comorbid cerebral amyloid angiopathy and isolated cortical venous thrombosis.

BACKGROUND AND AIM: The differentiation of isolated cortical venous thrombosis (ICVT) from cerebral amyloid angiopathy (CAA) can be difficult because both diseases share similar neurological symptoms and imaging findings. N-methyl-11C-2-(4'-methylaminophenyl)-6-hydroxybenzo-thiazole (11C-PiB) positron emission tomography (PET) functions as a diagnostic modality for CAA by detecting amyloid deposition. The present prospective study evaluated amyloid deposition using 11C-PiB-PET in consecutive patients with suspected ICVT. METHOD: This study was a prospective observational study. Patients who attended or were hospitalized between May 2019 and March 2020 were included in the analysis. Consecutive patients who met the criteria for suspicion of ICVT were enrolled in the study, and the clinical course, symptoms, imaging findings (including magnetic resonance imaging), and the 11C-PiB-PET findings of each case were analyzed. RESULTS: The study cohort included four patients (64-82 years of age, all women). In one younger patient, 11C-PiB-PET afforded no findings suggestive of CAA, whereas the remaining three patients exhibited 11C-PiB-PET findings suggestive of CAA. CONCLUSION: Although 11C-PiB-PET would be a reasonable modality for distinguishing ICVT from CAA, especially in younger patients, it might be difficult to differentiate ICVT from CAA in elderly patients because of the potential deposition of amyloid. CLINICAL TRIAL REGISTRATION: URL: https://www.umin.ac.jp/ctr/ Unique identifier: UMIN 000037101.

A 5-Minute Delay From Bolus Injection to Infusion Halves Plasma Concentration of Tissue Plasminogen Activator.

BACKGROUND: Reducing the time between onset of cerebral infarction and treatment with tissue plasminogen activator improves the prognosis of patients with cerebral infarction. Diverse dosing protocols have been developed with the aim of reducing the time to bolus injection; however, only a few studies have investigated the methods and effects of the interrupted time between bolus and post-bolus infusion. OBJECTIVE: We evaluated the impact of the interrupted time on pharmacokinetic parameters. METHODS: We calculated the changes in alteplase concentration after a bolus injection with high precision, in relation to different interval times. Simulations were performed using the linpk package of the statistical analysis software R. Post-bolus infusion was initiated at 0-, 5-, 15-, and 30-min intervals after bolus dosing. The calculation interval was set as 6 s. RESULTS: Alteplase concentration rose to 1.23 mg/mL after bolus dosing. However, it dropped to 0.53 mg/mL (43.4%) during a 5-min interval, 0.27 mg/mL (22.23%) during a 15-min interval, and 0.10 mg/mL (8.38%) during a 30-min interval. CONCLUSIONS: Because of the short half-life of alteplase, even a short delay in initiating post-bolus infusion can cause a significant reduction in serum alteplase concentration.

Evaluation of cholesterol crystals in carotid plaque by dual energy computed tomography.

Cholesterol crystals (CCs) in carotid plaques might be an indicator of vulnerability, although they have not been fully investigated and non-invasive methods of assessment have not been established. This study examines the validity of assessing CCs using dual-energy computed tomography (DECT) that uses X-rays with different tube voltages for imaging, allowing material discrimination. We retrospectively evaluated patients who had undergone preoperative cervical computed tomography angiography and carotid endarterectomy between December 2019 and July 2020. We developed CC-based material decomposition images (MDIs) by scanning CCs crystallized in the laboratory using DECT. We compared the percentage of CCs in stained slides defined by cholesterol clefts with the percentage of CCs displayed by CC-based MDIs. Thirty-seven pathological sections were obtained from 12 patients. Thirty-two sections had CCs; of these, 30 had CCs on CC-based MDIs. CC-based MDIs and pathological specimens showed a strong correlation. Thus, DECT allows the evaluation of CCs in carotid artery plaques.

Rapid Evaluation of Large Vessel Occlusion for Mechanical Thrombectomy Using Carotid Duplex Ultrasound.

Objectives This study clarified the usefulness of carotid duplex ultrasound (CDU) in evaluating large vessel occlusion (LVO) in patients with acute stroke planned to be treated with mechanical thrombectomy (MT). Methods This study was single-center, prospective, observational trial. If the ratio of end-diastolic velocity in the common carotid arteries was ≥1.4, or diastolic flow in the affected internal carotid artery (ICA) was absent on CDU, patients were immediately transferred to the angio-suite without additional cerebrovascular imaging. Clinical parameters, including time metrics and outcomes, were evaluated in participants. Patients We enrolled stroke patients with a National Institutes of Health Stroke Scale score ≥6 and Alberta Stroke Program Early CT score ≥6 in whom MT could be initiated within 6 hours of the stroke onset. Results Among 140 patients screened during the study period, 48 were ultimately enrolled. Twenty-seven patients were diagnosed with LVO by CDU alone. CDU offered 83% sensitivity and 82% specificity for identifying the occlusion of the ICA or M1 segment of the middle cerebral artery. Among the 29 total patients treated with MT, 20 (67%) showed a modified Rankin Scale score ≤2 at 90 days. The door-to-puncture time was significantly shorter in patients evaluated by CDU alone (34 minutes) than in those evaluated by magnetic resonance angiography after CDU (47.5 minutes, p<0.001). Conclusion CDU might reduce the time metrics for early initiation of MT with good sensitivity and specificity in identifying LVO.

Identifying large vessel occlusion using the hyperdense artery sign in patients treated with mechanical thrombectomy.

OBJECTIVES: The hyperdense artery sign on non-contrast computed tomography-reconstructed images is useful for identifying large vessel occlusion in acute ischemic stroke. This study aimed to assess its efficacy in patients with large vessel occlusion treated with mechanical thrombectomy. MATERIALS AND METHODS: This retrospective and prospective single-centered study from June 2019 to May 2021 evaluated the use of non-contrast computed tomography-reconstructed images for detecting hyperdense artery sign to identify large vessel occlusion from June 2020 to May 2021. We registered consecutive potential candidates for mechanical thrombectomy due to suspected stroke and assessed the accuracy of hyperdense artery sign on non-contrast computed tomography-reconstructed images for large vessel occlusion in the hyperacute setting. Non-contrast computed tomography images were reconstructed into maximum intensity projection images with iterative reconstruction algorithms to detect hyperdense artery signs. We compared the door-to-puncture time and functional outcome at 90 days before and after employing non-contrast computed tomography-reconstructed images in patients with large vessel occlusion treated with mechanical thrombectomy. RESULTS: The cohort included 82 patients, wherein 47 were treated with mechanical thrombectomy. The sensitivity (96%) and specificity (94%) of hyperdense artery sign on non-contrast computed tomography-reconstructed images for large vessel occlusion were performed. The door-to-puncture time was significantly shortened after using non-contrast computed tomography-reconstructed images (49 versus 28 min, p = 0.001), but the functional outcome at 90 days remained unchanged. CONCLUSIONS: Non-contrast computed tomography-reconstructed images, as a vascular imaging tool for mechanical thrombectomy, can reduce workflow time in hospitals by identifying large vessel occlusion with high sensitivity and specificity.

Impact of Patency of the Carotid Terminus and Middle Cerebral Artery on Early Clinical Outcomes in Patients with Acute Internal Carotid Artery Occlusion and Mild Symptoms.

INTRODUCTION: Both collateral flow via the internal carotid artery (ICA) terminus (ICT) and initial mild symptoms might be associated with favorable outcomes in patients with acute ICA occlusion (ICAO). This study aimed to address the association between early clinical outcomes and patency of the ICT and middle cerebral artery (MCA) in patients with acute ICAO with mild symptoms. METHODS: Of 1,214 consecutive patients with acute ischemic stroke or transient ischemic attack due to large vessel occlusion, patients with ipsilateral ICAO and initial National Institutes of Health Stroke Scale (NIHSS) score ≤5 were retrospectively enrolled. We examined the associations between clinical factors including patency of the ICT and MCA and recurrence of stroke or early neurological deterioration (REND). Significant early neurological deterioration was defined as increment in NIHSS score ≥1 during hospital stay. RESULTS: Thirteen of the 35 patients who were finally enrolled had REND (37%), and median modified Rankin scale (mRS) score at discharge was 1 (interquartile range, 0-4). Initial NIHSS score (4 vs. 1, p < 0.001) and rates of diabetes mellitus (61.5% vs. 13.6%, p = 0.007), intravenous thrombolysis (IVT) (30.9% vs. 0%, p = 0.014), and mechanical thrombectomy (MT) (23.1% vs. 0%, p = 0.044) were significantly higher in patients with REND rather than in those without. The rate of patent ICT and MCA was comparable between groups. Except for 1 patient who underwent MT promptly after IVT immediately after REND, 3 patients initially treated with IVT deteriorated after the procedure. One patient without patent ICT and MCA did not meet the indications for MT. In 2 other patients with patent ICT and MCA, MT was not initially performed, but was eventually performed because of REND due to thrombus migration, and both were discharged with an mRS score of 5. CONCLUSION: The overall clinical outcomes of patients with acute ICAO with mild symptoms were not depending on the patency of the ICT and MCA, but initial treatment with IVT alone might risk unfavorable outcomes due to thrombus migration in patients with patent ICT and MCA.

A case of ischemic stroke accompanied by multiple arterial dissections associated with Klippel-Feil syndrome.

OBJECTIVES: To describe the case of an ischemic stroke patient with Klippel-Feil syndrome who developed multiple aneurysms and discuss the mechanism of aneurysm development. MATERIALS AND METHODS: A 44-year-old man presented with dizziness, left hemiparesis, and left-sided numbness and was admitted to our department. He developed multiple aneurysms at the bilateral vertebral artery (VA) and bilateral internal carotid artery. RESULTS: We diagnosed the etiology of his brain infarction as an embolic stroke caused by left VA dissection or the large thrombosed aneurysm. Furthermore, we considered that arterial dissection or Hox gene mutation was associated with the development of multiple aneurysms. CONCLUSION: While previous reports have described single aneurysm, this is the first report of multiple aneurysms associated with Klippel-Feil syndrome.

Clinical characteristics of patients with lateral medullary infarction who had fatal respiratory failure.

INTRODUCTION: Respiratory failure is a fatal complication of lateral medullary infarction (LMI). However, the clinical characteristics associated with respiratory failure in patients with LMI have not been fully elucidated. We aimed to evaluate the clinical characteristics associated with respiratory failure in patients with LMI. METHODS: Among the 6365 consecutive patients who were admitted to our institute within 7 days of onset of acute ischemic stroke between January 2007 and December 2019, we identified those with acute LMI as verified by magnetic resonance imaging. We evaluated the associations between clinical characteristics and fatal respiratory failure that occurred within 10 days of stroke onset. RESULTS: Of 102 patients with acute LMI, eight had fatal respiratory failure within 10 days of stroke onset. Patients with fatal respiratory failure had a higher premorbid modified Rankin Scale score than did those without (3 vs. 0, p < 0.001), as well as a higher frequency of pulmonary disease (37.5% vs. 2.1%, p = 0.003). Severe dysphagia (100% vs. 30.9%, p < 0.001), dysarthria (100% vs. 56.4%, p = 0.020), ipsilateral hemiparesis (50.0% vs. 5.3%, p = 0.002), and urinary retention (50.0% vs. 2.1%, p < 0.001) were also significantly more common in patients with fatal respiratory failure than in those without. There were no significant differences in infarct locations between patients with fatal respiratory failure and those without. CONCLUSIONS: Assessment of pre-stroke history and monitoring of neurological symptoms that occur during the first 10 days post-stroke onset would be useful for predicting the risk of respiratory failure in patients with acute LMI.

Irreversible Homonymous Hemianopia Associated with Severe Hyperglycemia and Cerebral Hyperperfusion: A Case Report and Literature Review.

A 68-year-old man was admitted to our department because of left incomplete homonymous hemianopia accompanied by hyperglycemia. Both T2-weighted and diffusion-weighted imaging revealed a low signal intensity along the subcortex and high signal intensity along the cortex on the right parietal and occipital lobes. Furthermore, arterial spin labeling and single-photon emission computed tomography showed hyperperfusion at the right parieto-occipital lobe. However, the electroencephalography result was normal. Hyperperfusion improved after controlling the blood glucose levels; nevertheless, homonymous hemianopia remained. We suspect that the irreversible brain damage was attributable to hyperperfusion associated with long-term hyperglycemia.

Proximal Common Carotid Artery Stenosis Induced by Repetitive Mechanical Compression: A Case Report.

OBJECTIVES: Arterial branches and curvatures, such as the common carotid artery (CCA) origin and carotid bifurcation, are usual sites of atherosclerosis, which leads to carotid artery stenosis. Atherosclerosis may occur due to repetitive compression. Stenosis localized to the proximal segment away from the CCA origin and bifurcation is rare. Here, we describe the case of a patient with right proximal CCA stenosis induced by repetitive compression. METHODS: We studied an acute stroke patient who worked for a long time as a geographical surveyor carrying a tripod on his right shoulder. We found severe eccentric stenosis composed of thick plaque in the right proximal CCA, away from the right CCA origin. However, there was no finding of CCA dissection or vasculitis. RESULTS: The patient was diagnosed with ischemic stroke due to artery-to-artery embolization from the right CCA stenosis, which we believed was due to repetitive compression by the tripod. CONCLUSIONS: Repetitive mechanical stimuli can cause stenotic lesions at atypical vascular sites.

Duplicated middle cerebral artery associated with aneurysm at M1/M2 bifurcation: a case report.

BACKGROUND: A duplicated middle cerebral artery arises from the internal carotid artery and supplies blood to the middle cerebral artery territory. A duplicated middle cerebral artery is sometimes associated with an intracranial aneurysm. Most aneurysms associated with duplicated middle cerebral artery are located at the origin of the duplicated middle cerebral artery. An aneurysm located at the distal middle cerebral artery is not common. CASE PRESENTATION: We encountered a 62-year-old Asian man with duplicated middle cerebral artery associated with aneurysms at the M1/M2 junction of the duplicated middle cerebral artery and top of the internal carotid artery. CONCLUSIONS: In cases of duplicated middle cerebral artery, association with a distal aneurysm on the duplicated middle cerebral artery is rare. However, the aneurysm may be formed on the thicker middle cerebral artery due to hemodynamic stress.

Agenesis of the Left Internal Carotid Artery Associated with Dolichoectatic Intracranial Arteries.

A 28-year-old man without a significant medical history visited our hospital complaining of a headache. Computed tomography (CT) demonstrated thick, calcified vertebral artery (VA) and basilar artery (BA), despite the patient being young. Magnetic resonance angiography demonstrated the absence of the left internal carotid artery (ICA). The right ICA, the bilateral VA, and the BA were well developed and dolichoectatic. CT revealed the absence of the carotid canal on the left side. The condition was diagnosed as congenital agenesis of the left ICA with dolichoectatic changes in 3 other arteries. In a young patient with thick, calcified intracranial arteries, close examination is necessary, because vascular anomalies such as ICA agenesis may exist.

Superficial Temporal Artery-Middle Cerebral Artery Bypass Using a Thick STA after Endarterectomy: A Rescue Technique.

Background and Objective Superficial temporal artery (STA)-middle cerebral artery (MCA) bypass is a procedure to reconstruct cerebral blood flow in the MCA territory. In some cases, the STA wall is thickened and the size discrepancy between STA and MCA is apparent. In such a situation, STA-MCA bypass is challenging. We present two patients who underwent STA-MCA bypass using STA in which a thickened intima was removed. We discuss the usefulness of this rescue technique. Patients and Results A patient with an atherosclerotic MCA occlusion and another with an occluded internal carotid artery are included. Endarterectomy of STA was performed before or during anastomosis, and the intima-resected STA was anastomosed to MCA. In both cases, the STA was thick and hard, and it was difficult to anastomose the STA as it was to the MCA. Patency of the bypass was confirmed by postoperative angiography. Conclusion Endarterectomy of a thickened STA might be an effective rescue technique in cases with severely atherosclerotic STA in STA-MCA bypass.

Late Seizures after Stroke in Clinical Practice: The Prevalence of Non-convulsive Seizures.

Objective The prevalence of the non-convulsive type of late seizure after stroke is unknown. The aim of the present study was to clarify the characteristics of late seizure in clinical practice, mainly focusing on the prevalence of non-convulsive seizure. Methods A total of 178 consecutive patients who were admitted and diagnosed with late seizure after stroke were retrospectively enrolled, and the data of 127 patients for whom the complete seizure was observed by a bystander were analyzed. Clinical information was obtained from the medical records and nursing notes. Results A non-convulsive seizure was observed in 37 patients (29%). A focal seizure and its secondary generalization accounted for 79% of the seizure types. Status epilepticus was observed in 60 patients (47%), including 11 patients (9%) without convulsion. The patients with non-convulsive seizures were significantly younger than those with convulsive seizures, but there were no other significant differences between the two groups with respect to sex, classification or the lesion of stroke. Conclusion There was a high rate of non-convulsive seizures in patients with late seizure after stroke. A non-convulsive seizure may be caused by any type or location of preceding stroke. More attention is needed in the differential diagnosis of neurological deterioration after stroke.

Pseudoaneurysm formation due to rupture of intracranial aneurysms: Case series and literature review.

Background Intracranial pseudoaneurysm formation due to a ruptured non-traumatic aneurysm is extremely rare. We describe the radiological findings and management of pseudoaneurysms due to ruptured cerebral aneurysms in our case series and previously reported cases. Patients and methods Four additional and 20 reported patients presenting with subarachnoid hemorrhage (SAH) are included. Radiological findings and clinical features of these patients were reviewed. Results In our series, three-dimensional computed tomographic angiography (3D-CTA) and/or angiography showed an irregular- or snowman-shaped cavity extending from the parent artery. The radiological examination additionally revealed delayed filling and retention of contrast medium. These findings were the same as previously reported cases. One patient underwent direct clipping of the true aneurysm. For the other three patients with aneurysms at the basilar and anterior communicating arteries, the true portion of the aneurysm was embolized with platinum coils. During the procedures, care was taken not to insert the coils into the distal pseudoaneurysm portion to prevent rupture. The review of 24 cases revealed that the location of the aneurysms was most frequent in the anterior communicating artery (41.7%), and 86.7% of patients were in a severe stage of SAH (>Grade 3 in WFNS or Hunt & Kosnik grading) implying abundant SAH. Conclusions Pseudoaneurysm formation in SAH after non-traumatic aneurysm rupture is rare. However, in cases with an irregular-shaped aneurysm cavity, pseudoaneurysm formation should be taken into consideration.

Primary aldosteronism in patients with acute stroke: prevalence and diagnosis during initial hospitalization.

BACKGROUND: Hypertension is the prime risk factor for stroke, and primary aldosteronism (PA) is the most common cause of secondary hypertension. The prevalence of PA in stroke patients has never been reported. The aim of this study was to elucidate the prevalence of PA. METHODS: A total of 427 consecutive patients with acute stroke were prospectively enrolled for this study. The screening tests were performed at the initial visit and a week after admission by measuring plasma aldosterone concentration and plasma renin activity. The rapid adrenocorticotropic hormone (ACTH) test was performed as the confirmatory test when both screening tests were positive. The primary endpoint was a final diagnosis of PA. RESULTS: The sensitivity of the dual screening system for the diagnosis of PA was 88.2 %, and PA was finally diagnosed in 4.0 % of acute stroke patients and in 4.9 % of stroke patients with a history of hypertension. Patients with PA were less likely to be male and have diabetes, and they had higher blood pressure at the initial visit, lower potassium concentration, and more intracerebral hemorrhage. The rapid ACTH test was performed safely even in acute stroke patients. CONCLUSIONS: The prevalence of PA is not low among acute stroke patients. Efficient screening of PA should be performed particularly for patients with risk factors. TRIAL REGISTRATION: UMIN-CTR; UMIN000011021 . Trial registration date: June 23, 2013 (retrospectively registered).

Post-ischaemic hyperperfusion in traumatic middle cerebral artery dissection detected by arterial spin labelling of magnetic resonance imaging.

We report a patient with a traumatic middle cerebral artery dissection, which showed hyperperfusion in the territory supplied by the left middle cerebral artery. A 45-year-old man experienced speech disturbance and motor weakness in his right hemibody on the day following mild head trauma. His symptoms worsened on the fourth day. Magnetic resonance imaging showed narrowing in the left M1 portion of the middle cerebral artery. Angiography showed narrowing and dilatation in the left middle cerebral artery trunk. The lesion was diagnosed as a dissection of the middle cerebral artery. Arterial spin labelling of magnetic resonance imaging and single photon emission computed tomography showed increased cerebral blood flow in the left temporal region compared with the right. The patient was treated conservatively and the symptoms gradually improved. The hyperperfusion observed on arterial spin labelling and single photon emission computed tomography gradually improved and disappeared on the 25th day. This is the first reported case of traumatic middle cerebral artery dissection, which showed post-ischaemic hyperperfusion in the territory of the affected artery. To detect hyperperfusion in the brain, arterial spin labelling is a useful technique.

Cavernous Sinus Dural Arteriovenous Fistula Patients Presenting With Headache as an Initial Symptom.

Cavernous sinus (CS) dural arteriovenous fistula (dAVF) patients presenting with only headache as an initial symptom are not common. Patients with CS-dAVF commonly present with symptoms related to their eyes. In all three patients, headache was the initial symptom. Other symptoms related to the eyes developed 1 - 7 months after headache. In one patient, headache was controlled by sumatriptan succinate, but not diclofenac sodium or loxoprofen sodium. In another patient, headache was controlled by loxoprofen sodium. In the third patient, headache was improved by stellate ganglion block. In all patients, magnetic resonance angiography (MRA) in the early stage of the clinical course showed abnormal blood flow in the CS. However, reflux to the superior ophthalmic vein (SOV) was not detected. As treatment, transarterial and transvenous embolizations were necessary for one patient, and transvenous embolization was performed for another patient with significant blood flow to the SOV and cortical veins. On the other hand, manual compression of the bilateral carotid arteries at the neck resulted in disappearance of the fistula in the third patient. In all patients, the symptoms improved after the disappearance of blood reflux to the CS. The refluxed blood to the CS might cause elevation of the CS pressure and stimulate the trigeminal nerve in the dural membrane, resulting in headache before developing reflux in an anterior direction. CS-dAVF could induce both migraine and common headache. In cases with blood reflux to the CS on magnetic resonance imaging and/or MRA even without eye symptoms, a differential diagnosis of CS-dAVF should be taken into consideration.