Endovascular Versus Medical Therapy in Posterior Cerebral Artery Stroke: Role of Baseline NIHSS Score and Occlusion Site.

BACKGROUND: Acute ischemic stroke with isolated posterior cerebral artery occlusion (iPCAO) lacks management evidence from randomized trials. We aimed to evaluate whether the association between endovascular treatment (EVT) and outcomes in iPCAO acute ischemic stroke is modified by initial stroke severity (baseline National Institutes of Health Stroke Scale [NIHSS]) and arterial occlusion site. METHODS: Based on the multicenter, retrospective, case-control study of consecutive iPCAO acute ischemic stroke patients (PLATO study [Posterior Cerebral Artery Occlusion Stroke]), we assessed the heterogeneity of EVT outcomes compared with medical management (MM) for iPCAO, according to baseline NIHSS score (≤6 versus >6) and occlusion site (P1 versus P2), using multivariable regression modeling with interaction terms. The primary outcome was the favorable shift of 3-month modified Rankin Scale (mRS). Secondary outcomes included excellent outcome (mRS score 0-1), functional independence (mRS score 0-2), symptomatic intracranial hemorrhage, and mortality. RESULTS: From 1344 patients assessed for eligibility, 1059 were included (median age, 74 years; 43.7% women; 41.3% had intravenous thrombolysis): 364 receiving EVT and 695 receiving MM. Baseline stroke severity did not modify the association of EVT with 3-month mRS distribution (Pinteraction=0.312) but did with functional independence (Pinteraction=0.010), with a similar trend on excellent outcome (Pinteraction=0.069). EVT was associated with more favorable outcomes than MM in patients with baseline NIHSS score >6 (mRS score 0-1, 30.6% versus 17.7%; adjusted odds ratio [aOR], 2.01 [95% CI, 1.22-3.31]; mRS score 0 to 2, 46.1% versus 31.9%; aOR, 1.64 [95% CI, 1.08-2.51]) but not in those with NIHSS score ≤6 (mRS score 0-1, 43.8% versus 46.3%; aOR, 0.90 [95% CI, 0.49-1.64]; mRS score 0-2, 65.3% versus 74.3%; aOR, 0.55 [95% CI, 0.30-1.0]). EVT was associated with more symptomatic intracranial hemorrhage regardless of baseline NIHSS score (Pinteraction=0.467), while the mortality increase was more pronounced in patients with NIHSS score ≤6 (Pinteraction=0.044; NIHSS score ≤6: aOR, 7.95 [95% CI, 3.11-20.28]; NIHSS score >6: aOR, 1.98 [95% CI, 1.08-3.65]). Arterial occlusion site did not modify the association of EVT with outcomes compared with MM. CONCLUSIONS: Baseline clinical stroke severity, rather than the occlusion site, may be an important modifier of the association between EVT and outcomes in iPCAO. Only severely affected patients with iPCAO (NIHSS score >6) had more favorable disability outcomes with EVT than MM, despite increased mortality and symptomatic intracranial hemorrhage.

Clinical characteristics, Risk factors, and outcomes of Posterior circulation stroke: A retrospective study between younger and older adults in Saudi Arabia.

INTRODUCTION: Posterior circulation stroke (PCS) may be less prevalent than its anterior counterpart but contributes to substantial morbidity and mortality. The aim was to characterize PCS's demographics, clinical presentation, management, and outcomes between younger and older adults in Saudi Arabia. METHODS: This retrospective cohort study was conducted at two tertiary medical centers in Saudi Arabia between March 2016 and December 2020. All patients who presented with symptoms of posterior circulation stroke and had positive brain imaging were included. RESULTS: The study involved 160 posterior circulation stroke patients, stratified into two age groups: 71 patients aged 18-59 years and 89 patients aged 60 years and above. The mean age of the entire cohort was 60.9 years, and 77 % were males. Hypertension was more prevalent in the older age group (88 % vs. 69 %, p=0.005), and smoking was significantly higher among younger patients (38 % vs. 15 %; p=0.0009). Only 22.4 % received thrombolysis and/or thrombectomy. Most strokes involved the posterior cerebral artery (45.6 %). Large artery atherosclerosis was the most common subtype. At discharge, younger patients had higher NIHSS compared to older patients. CONCLUSION: Our investigation of 160 PCS patients in Saudi Arabia uncovers notable trends: a mere 22.4 % received thrombolysis and/or thrombectomy and a significant prevalence of posterior cerebral artery involvement due to large artery atherosclerosis. The study further reveals younger patients disproportionately had severe outcomes. Highlighting the need for improved stroke care and heightened awareness, this research contributes vital data to an underexplored domain, urging further study to optimize care and understand PCS dynamics in Saudi Arabia.

Psychotic Disorder after Left Posterior Cerebral Artery Stroke-An Atypical Event.

INTRODUCTION: Stroke survivors usually present physical and neuropsychiatric complications. Post-stroke psychosis (PSPsy) is a particularly neglected sequel despite its disruptive nature. OBJECTIVES: To present a case of early emerging neuropsychiatric symptoms following a left posterior cerebral artery (PCA) stroke. To review and discuss PSPsy clinical manifestations, pathophysiology, and clinical outcomes. CLINICAL CASE: A previously autonomous 68-year-old woman with vascular risk factors and depressive disorder presented to the emergency department with a 5-day history of disorientation, motor aphasia, and right hypoesthesia. Computer tomography revealed a left PCA stroke. She was started on acetylsalicylic acid and rosuvastatin and discharged the next day. Afterward, the patient developed a depressive mood, emotional lability, periods of confusion, delusions of persecution, guilt and unworthiness, auditory hallucinations, and suicide ideation. She was admitted to a psychiatric hospital and started on risperidone with a good response, being discharged after 15 days with the resolution of psychiatric symptoms. CONCLUSIONS: PSPsy is more common after right hemisphere lesions and usually develops after some months. Nevertheless, our patient presented PSPsy following an ischemic event of the left PCA, with neuropsychiatric symptomatology dominating the clinic since the beginning. The involvement of the retrosplenial cortex or its connections was likely important for this atypical presentation. Due to the lack of guidelines on approaching PSPsy, most patients are treated with the same strategies used for non-stroke patients. A better comprehension of the anatomical basis underlining the symptomatology in these patients could deepen the understanding of psychosis and psychotic disorders.

Presenting Symptoms and Imaging Features of Posterior Cerebral Artery Stroke Causing Homonymous Hemianopia.

BACKGROUND: Posterior cerebral artery (PCA) stroke is a common cause of homonymous hemianopia and other neurologic deficits associated with more proximal ischemia in the vertebrobasilar circuit. Localization of the process can be challenging unless the symptom complex is well recognized, yet early diagnosis is critical to forestall dangerous driving and repeated stroke. We undertook this study to provide additional detail about the presenting symptoms and signs and their correlation with imaging abnormalities and stroke etiology. METHODS: Retrospective study of medical records of patients presenting to a single tertiary care academic center between 2009 and 2020 with homonymous hemianopia from PCA stroke. We excerpted data on symptoms, visual and neurologic signs, incident medical procedures and diagnoses, and imaging features. We determined stroke etiology using the Causative Classification Stroke system. RESULTS: In a cohort of 85 patients, 90% of strokes occurred without preceding symptoms. But in retrospect, 10% of strokes did have warning symptoms. In 20% of patients, strokes followed within 72 hours of a medical or surgical procedure or newly identified medical condition. In the subgroups of patients whose records contained a description of visual symptoms, 87% reported the visual sensation as negative, and 66% realized that it was located in a hemifield in both eyes. Concurrent nonvisual symptoms were present in 43% of patients, consisting commonly of numbness, tingling, and new headache. Infarction located outside the visual cortex affected primarily the temporal lobe, thalamus, and cerebellum, reflecting the widespread nature of ischemia. Nonvisual clinical manifestations and arterial cutoffs on imaging were associated with thalamic infarction, but the clinical features and location of the infarction did not correlate with the etiology of the stroke. CONCLUSIONS: In this cohort, clinical localization of the stroke was aided by the fact that many patients could lateralize their visual symptoms and had nonvisual symptoms suggestive of ischemia affecting the proximal vertebrobasilar circuit. Numbness and tingling were strongly linked to concurrent thalamic infarction. Clinical features and infarct location were not associated with the etiology of the stroke.

Demographics, Risk Factors, and Etiology of Posterior Cerebral Artery Stroke Causing Homonymous Hemianopia.

BACKGROUND: Posterior cerebral artery (PCA) strokes account for up to 10% of all ischemic strokes, often presenting with homonymous hemianopia. The proportion of these strokes attributed to various etiologies varies widely in previously published studies, owing largely to differing patient populations, definitions of stroke pathogenesis, and vascular territories involved. The Causative Classification System (CCS), an automated version of the Stop Stroke Study (SSS) Trial of Org 10,172 in Acute Stroke Treatment (TOAST) system, allows for a more rigorous assignment of stroke etiology. METHODS: We excerpted clinical and imaging data on 85 patients who had PCA stroke with homonymous hemianopia examined at the University of Michigan. We compared the stroke risk factor profile of our PCA cohort with that of 135 patients with stroke in the distribution of the internal carotid artery (ICA) and middle cerebral artery (MCA) in an unpublished University of Michigan registry. We applied the CCS web-based calculator to our PCA cohort to determine stroke etiology. RESULTS: In our PCA cohort, 80.0% had at least 2 conventional stroke risk factors and 30.6% had 4 risk factors, most commonly systemic hypertension. The risk factor profile of our PCA cohort resembled that of our ICA/MCA cohort except that the mean age of our PCA cohort was more than a decade younger and had a significantly lower frequency of atrial fibrillation (AF) than our ICA/MCA cohort. In nearly half of the patients with AF in our PCA cohort, AF was diagnosed after the stroke. Among stroke etiologies in our PCA cohort, 40.0% were of undetermined cause, 30.6% were from cardioaortic embolism, 17.6% were from other determined causes, and only 11.8% were from supra-aortic large artery atherosclerosis. Strokes after endovascular or surgical interventions were prominent among other determined causes. CONCLUSIONS: Most patients in our PCA cohort had multiple conventional stroke risk factors, a finding not previously documented. Mean age at stroke onset and AF frequency were lower than in our ICA/MCA cohort, in agreement with previous studies. As some other studies have found, nearly 1/3 of strokes were attributed to cardioaortic embolism. Within that group, AF was often a poststroke diagnosis, a finding not previously highlighted. Compared with earlier studies, a relatively high portion of strokes were of undetermined etiology and of other determined etiologies, including stroke after endovascular or surgical interventions. Supra-aortic large artery atherosclerosis was a relatively uncommon explanation for stroke.

The amnestic syndrome of posterior cerebral artery infarction.

BACKGROUND AND PURPOSE: Little is known about the character and underlying lesions of ischaemic amnesia. Episodic memory functions and brain lesions were therefore studied in 84 patients with acute ischaemic infarcts in the supply territory of the posterior cerebral artery. The aim was also to learn how the neural memory systems are organized. METHODS: Standard neuropsychological tests were used to assess verbal and figural memory. Patients were split into memory-impaired and memory-intact groups. Lesions were demarcated, normalized and anatomically labelled, using standard mapping procedures. RESULTS: Of the 84 patients more than 80% had an amnestic syndrome, mostly with combined memory impairment, less often with figural or verbal memory impairment. Amnesia in subjects with left hemispheric lesions was more frequent and more severe, with significantly lower scores on the verbal memory test. Normal performance or figural amnesia were prevalent after right hemispheric lesions. However, no amnesia subtype was strictly tied to left- or right-sided brain damage. Hippocampal and thalamic lesions were common, but 30% of lesions were extrahippocampal located in the ventral occipito-temporal cortex and long occipital white matter tracts. Most amnestic patients lacked awareness for their memory impairment. CONCLUSIONS: Memory impairment is a key clinical manifestation of acute posterior cerebral artery stroke. Amnesia is more frequent and more severe after left stroke, suggesting a left hemisphere dominance of the two memory systems. Domain specific memory appears not to be strictly lateralized, since deficits in verbal and figural memory were found after lesions of both sides. Extrahippocampal lesions may also cause memory impairment.

Mechanical thrombectomy for acute posterior cerebral artery stroke; Feasibility and predictors of outcome.

PURPOSE: The territorial involvement and the clinical benefit of endovascular therapy (EVT) of the posterior cerebral artery (PCA) occlusion may vary between patients. The purpose of this study was to investigate the feasibility of mechanical thrombectomy (MT) in isolated posterior cerebral artery occlusions (IPCAOs) and the prognostic factors of EVT. METHODS: Forty-eight patients with acute PCA occlusion who underwent EVT between Mar 2008 and Apr 2021 from 2 tertiary centers were retrospectively analyzed. Clinical characteristics, imaging and perfusion abnormalities, and angiographic and clinical outcomes were analyzed. Ischemic changes were assessed with the posterior circulation Acute Stroke Prognosis Early Computed Tomography Score (pc-ASPECTS). Perfusion abnormalities were assessed using automated software for Tmax volume measurement and identification of Tmax involved in PCA eloquent areas. RESULTS: The IPCAO sites were P1 (n = 17) and P2 (n = 31). Overall successful recanalization (mTICI 2b/3) was achieved in 68.8% (33/48) and excellent outcome (90-day mRS 0-1) in 52.1% (25/48) of the patients. Excellent/non-excellent outcome was associated with male sex (p = 0.036), admission NIHSS (p = 0.002), pc-ASPECTS (p = 0.035), Tmax > 6 s involvement of the midbrain-thalamus (p = 0.008), first-line stent-retriever thrombectomy (p = 0.036), complete recanalization (p = 0.009), and modified first pass effect (FPE, p = 0.047). Tmax>6 s involvement of the midbrain-thalamus was an independent predictor for non-excellent outcome on multivariable analysis. CONCLUSION: Acute stroke from IPCAO may be successfully treated with EVT. Tmax > 6 s involvement of the midbrain-thalamus on perfusion imaging may be a predictor for clinical outcome.

Accuracy of Visual Fields in Localizing MRI Lesions in Posterior Cerebral Artery Infarction.

BACKGROUND: The representation of the visual field in visual cortex was established over a century ago by correlating perimetric defects with the estimated location of war wounds. The availability of high-definition MRI offers the possibility of more precise correlation. METHODS: Homonymous hemianopias disclosed on automated visual fields (HVFs) were drawn from an electronic medical record search from 2009 to 2020 at the Michigan Medicine, a tertiary care academic medical center. The patterns of the visual field defects (VFDs) were interpreted by a consensus of 2 authors. The VFDs were correlated with the location of MRI lesions in 92 patients with posterior cerebral artery (PCA) domain ischemic strokes, as determined by the neuroradiologist author, who was masked as to the VFDs. RESULTS: Among the 77 VFDs confined to 1 hemifield, 74 (96%) correctly predicted the side of the visual cortex lesion. In 3 cases, the MRI lesion in the opposite cerebral hemisphere was not foretold. Among the 15 VFDs present in both hemifields, 5 (33.3%) overestimated the MRI lesions, which were evident in only 1 hemisphere. Among the 30 VFDs confined to 1 quadrant, 29 (97%) correctly predicted the lesioned visual cortex quadrant. However, 14 VFDs failed to predict MRI lesions present in both superior and inferior visual cortex quadrants on the same side. Those unpredicted lesions mostly had subtle or indistinct signal abnormalities or were confined to anterior visual cortex, an area that is inaccessible with the HVF test protocol used in this study. CONCLUSION: In this study of PCA ischemic stroke, VFDs limited to 1 hemifield were accurate in locating the side and quadrant of the MRI visual cortex lesions. However, the quadrantic VFDs sometimes failed to predict that the lesions involved both the superior and inferior quadrants on the same side, largely because those lesions had subtle imaging features that defied accurate radiologic assessment or were out of the reach of the visual field test protocol.

Correlation of Macular Sparing and Homonymous Paracentral Scotomas With MRI Lesions in Posterior Cerebral Artery Infarction.

BACKGROUND: The concepts of the representation of visual field in primary visual cortex are based on studies of war wounds and correlations with brain imaging in small cohorts. Because of the difficulty of judging brain lesion extent and the small number of studied patients, there is lingering controversy as to whether the central 15° of visual field are mapped onto the posterior 25% of primary visual cortex or onto a larger area. To improve the delineation of MRI lesion extent, we have studied only patients with posterior cerebral artery (PCA) ischemic strokes. METHODS: We accrued a cohort of 92 patients with PCA strokes from an electronic medical records search between 2009 and 2020 at a single tertiary care academic institution. Patients had reliable static perimetry demonstrating homonymous hemianopias and high-definition reviewable brain imaging. We divided the primary visual cortex on the MRI T1 sagittal sequence into 8 equal segments in right and left cerebral hemispheres and located lesions according to the segments they occupied. We correlated lesion locations with 3 visual field defects (VFDs): macular-sparing homonymous quadrantanopias, macular-splitting homonymous quadrantanopias, and homonymous paracentral scotomas. RESULTS: Among 25 cases with macular sparing, 13 had lesion-sparing confined to the posterior 25% of visual cortex. Among 6 cases with homonymous paracentral scotomas, 2 had lesions confined to the posterior 25% of visual cortex. Macular-splitting quadrantanopia did not occur in any patients with lesions confined to the posterior 25% of visual cortex, but did occur in 3 patients with lesions confined to the posterior 50% of visual cortex. These phenomena would not be expected if the central 15° of visual field were mapped onto a region extending beyond the posterior 25% of visual cortex. In patients with PCA strokes that involved the retrogeniculate visual pathway proximal to visual cortex, the visual cortex lesions were often less extensive than predicted by the VFDs, perhaps because of widespread damage to axons before they reached their destination in visual cortex. CONCLUSIONS: These results support the concept that the central 15° of the visual field are represented in the posterior 25% of visual cortex. Although this study contributes a larger cohort of patients with better-defined lesion borders than in past reports, its conclusions must be tempered by the variability of patient attention during visual field testing, the subjectivity in the interpretation of the defect patterns, and the difficulty in judging MRI lesion extent even on diffusion-weighted and precontrast T1 sagittal sequences.

Mechanisms of Stroke in Patients with Fetal Posterior Cerebral Artery.

OBJECTIVES: The fetal-type posterior cerebral artery (FTP) is a normal variation of the posterior cerebral artery (PCA), occurring in 3-36% of general population. The effects of the FTP in stroke mechanisms remain debatable. We aimed to investigate the differences in stroke mechanisms and lesion locations between patients with and without FTP. METHODS: A total of 394 patients with PCA territory stroke were divided into those with PCA ischemic stroke associated with ipsilateral FTP and those without. The baseline characteristics, vascular risk factors, infarct pattern, stroke location, stroke etiology, and the diameter of P1 in patients without FTP or posterior communicating artery (PcoA) in patients with FTP were investigated. RESULTS: Among the 394 patients, 52 (13.2%) PCA stroke patients with ipsilateral FTP were enrolled. Patients with FTP, in comparison with those without, had a higher frequency of deep infarct pattern (69.2% vs. 47.1%, P=0.012), small vessel occlusion (51.9% vs. 28.9%, P=0.009), ventrolateral thalamic involvement (65.4% vs. 49.1%, P=0.042), and a lower frequency of cardiac embolism (9.6% vs. 24.0%, P=0.009). The diameter of P1 in patients without FTP was larger than that of PcoA in patients with FTP (2.1 ± 0.3 mm vs. 1.6 ± 0.2 mm, P <0.001). CONCLUSIONS: The stroke mechanisms, infarct pattern, and the location of the stroke were different between patients with and without FTP. PCA stroke patients with FTP more often had small vessel occlusion and ventrolateral thalamic involvement. These results are probably associated with difference in the hemodynamic status according to the presence of FTP.

Visual texture agnosia caused by bilateral posterior cerebral artery stroke: a case study.

A 57-year-old man presented with a bilateral posterior cerebral artery attack and was visually impaired. He had a hard time identifying familiar faces and shades. He also felt that the familiar building looked different, and complained that it was not possible to tell from visual information alone whether the food was cooked or the kimono fabric was soft.We assessed the patient's visual function using real materials and material images and was diagnosed with visual texture agnosia. There are few reports of visual texture agnosia, detailed evaluation is considered important because perceiving texture is important for activities of daily living.

Splenial Restricted Diffusion as MRI Correlate of Diaschisis in a Blind Infant With Unilateral Posterior Cerebral Artery Stroke.

ABSTRACT: A 3-month-old male infant appeared on multiple clinical examinations to have acutely developed bilateral retrogeniculate blindness. Electroencephalography showed focal status epilepticus confined to the left posterior cerebral hemisphere. MRI demonstrated restricted diffusion in the domain of the left posterior cerebral artery consistent with acute stroke. Notably, the restricted diffusion extended across the midline in the splenium of the corpus callosum. This splenial sign may be the imaging correlate of cerebral diaschisis, a well-described phenomenon in which patients with new brain lesions develop acutely impaired neurologic function in related but nonlesioned brain regions. Diaschisis has been posited as the explanation for the temporary bilateral blindness in adult patients suffering from unilateral occipital infarctions.

Early Brain Imaging Shows Increased Severity of Acute Ischemic Strokes With Large Vessel Occlusion in COVID-19 Patients.

BACKGROUND AND PURPOSE: Reports are emerging regarding the association of acute ischemic strokes with large vessel occlusion and coronavirus disease 2019 (COVID-19). While a higher severity of these patients could be expected from the addition of both respiratory and neurological injury, COVID-19 patients with strokes can present with mild or none respiratory symptoms. We aimed to compare anterior circulation large vessel occlusion strokes severity between patients with and without COVID-19. METHODS: We performed a comparative cohort study between patients with COVID-19 who had anterior circulation large vessel occlusion and early brain imaging within 3 hours from onset, in our institution during the 6 first weeks of the COVID-19 outbreak and a control group admitted during the same calendar period in 2019. RESULTS: Twelve COVID-19 patients with anterior circulation large vessel occlusion and early brain imaging were included during the study period and compared with 34 control patients with anterior circulation large vessel occlusion and early brain imaging in 2019. Patients in the COVID-19 group were younger (P=0.032) and had a history of diabetes mellitus more frequently (P=0.039). Patients did not significantly differ on initial National Institutes of Health Stroke Scale nor time from onset to imaging (P=0.18 and P=0.6, respectively). Patients with COVID-19 had more severe strokes than patients without COVID-19, with a significantly lower clot burden score (median: 6.5 versus 8, P=0.016), higher rate of multivessel occlusion (50% versus 8.8%, P=0.005), lower DWI-ASPECTS (Diffusion-Weighted Imaging-Alberta Stroke Program Early CT Scores; median: 5 versus 8, P=0.006), and higher infarct core volume (median: 58 versus 6 mL, P=0.004). Successful recanalization rate was similar in both groups (P=0.767). In-hospital mortality was higher in the COVID-19 patients' group (41.7% versus 11.8%, P=0.025). CONCLUSIONS: Early brain imaging showed higher severity large vessel occlusion strokes in patients with COVID-19. Given the massive number of infected patients, concerns should be raised about the coming neurovascular impact of the pandemic worldwide.

Clinical Course of Acute Ischemic Stroke Due to Medium Vessel Occlusion With and Without Intravenous Alteplase Treatment.

BACKGROUND AND PURPOSE: Available data on the clinical course of patients with acute ischemic stroke due to medium vessel occlusion (MeVO) are mostly limited to those with M2 segment occlusions. Outcomes are generally better compared with more proximal occlusions, but many patients will still suffer from severe morbidity. We aimed to determine the clinical course of acute ischemic stroke due to MeVO with and without intravenous alteplase treatment. METHODS: Patients with MeVO (M2/M3/A2/A3/P2/P3 occlusion) from the INTERRSeCT (The Identifying New Approaches to Optimize Thrombus Characterization for Predicting Early Recanalization and Reperfusion With IV Alteplase and Other Treatments Using Serial CT Angiography) and PRoveIT (Precise and Rapid Assessment of Collaterals Using Multi-Phase CTA in the Triage of Patients With Acute Ischemic Stroke for IA Therapy) studies were included. Baseline characteristics and clinical outcomes were summarized using descriptive statistics. The primary outcome was a modified Rankin Scale score of 0 to 1 at 90 days, describing excellent functional outcome. Secondary outcomes were the common odds ratio for a 1-point shift across the modified Rankin Scale and functional independence, defined as modified Rankin Scale score of 0 to 2. We compared outcomes between patients with versus without intravenous alteplase treatment and between patients who did and did not show recanalization on follow-up computed tomography angiography. Logistic regression was used to provide adjusted effect-size estimates. RESULTS: Among 258 patients with MeVO, the median baseline National Institutes of Health Stroke Scale score was 7 (interquartile range: 5-12). A total of 72.1% (186/258) patients were treated with intravenous alteplase and in 41.8% (84/201), recanalization of the occlusion (revised arterial occlusive lesion score 2b/3) was seen on follow-up computed tomography angiography. Excellent functional outcome was achieved by 50.0% (129/258), and 67.4% (174/258) patients gained functional independence, while 8.9% (23/258) patients died within 90 days. Recanalization was observed in 21.4% (9/42) patients who were not treated with alteplase and 47.2% (75/159) patients treated with alteplase (P=0.003). Early recanalization (adjusted odds ratio, 2.29 [95% CI, 1.23-4.28]) was significantly associated with excellent functional outcome, while intravenous alteplase was not (adjusted odds ratio, 1.70 [95% CI, 0.88-3.25]). CONCLUSIONS: One of every 2 patients with MeVO did not achieve excellent clinical outcome at 90 days with best medical management. Early recanalization was strongly associated with excellent outcome but occurred in <50% of patients despite intravenous alteplase treatment.

Mechanical Thrombectomy in Medium Vessel Occlusions: Blind Exchange With Mini-Pinning Technique Versus Mini Stent Retriever Alone.

BACKGROUND AND PURPOSE: Mechanical thrombectomy techniques for intracranial medium vessel occlusions (MeVOs) have evolved in recent years, although the optimal approach is still unclear. The aim of this study was to investigate the effectiveness and safety of mechanical thrombectomy in MeVOs using mini (0.017 inches microcatheter compatible) stent retrievers combined with low-profile (0.035 inches distal inner diameter) distal aspiration catheters through the blind exchange/mini-pinning (BEMP) technique compared with mini stent retrievers alone. METHODS: Retrospective review of a prospectively maintained database of patients treated with the BEMP technique or mini stent retriever alone for intracranial MeVOs from 2017 to 2020 in a comprehensive stroke center. Both groups were compared about baseline characteristics, occlusion site, clinical presentation, clot cause, procedural outcomes (MeVO first-pass and final expanded Thrombolysis in Cerebral Ischemia score, the mini stent retriever used, number of passes with the front-line approach, and need of rescue therapy), safety outcomes (emboli to unwanted territories and hemorrhagic complications), and clinical outcomes at 90 days. Multivariable logistic regression analysis was performed with potential predictors of vessel recanalization to find independent variables associated with MeVO first-pass expanded Thrombolysis in Cerebral Ischemia 2c/3 recanalization. RESULTS: We reviewed 102 patients/106 MeVOs treated with the BEMP technique (n=56) or mini stent retriever (n=50). There was a higher rate of MeVO first-pass expanded Thrombolysis in Cerebral Ischemia 2c/3 recanalization (57% versus 34%, P=0.017), lower need of rescue therapy (7.1% versus 22%, P=0.028), and lower rate of emboli to new territory (1.8% versus 12%, P=0.035) and symptomatic intracranial hemorrhage (1.9% versus 12.8%, P=0.038) with the BEMP technique. After multivariable analysis, the sole independent factor associated to MeVO first-pass expanded Thrombolysis in Cerebral Ischemia 2c/3 recanalization was the BEMP technique (odds ratio, 2.72 [95% CI, 1.19-6.22]; P=0.018). CONCLUSIONS: In the setting of MeVOs, the BEMP technique may lead to higher rates of the first-pass recanalization and a lower incidence of symptomatic intracranial hemorrhage than mini stent retrievers alone.

Detection and Quantification of Symptomatic Atherosclerotic Plaques With High-Resolution Imaging in Cryptogenic Stroke.

BACKGROUND AND PURPOSE: High-resolution vessel wall imaging (HR-VWI) is a powerful tool in diagnosing intracranial vasculopathies not detected on routine imaging. We hypothesized that 7T HR-VWI may detect the presence of atherosclerotic plaques in patients with intracranial atherosclerosis disease initially misdiagnosed as cryptogenic strokes. METHODS: Patients diagnosed as cryptogenic stroke but suspected of having an intracranial arteriopathy by routine imaging were prospectively imaged with HR-VWI. If intracranial atherosclerotic plaques were identified, they were classified as culprit or nonculprit based on the likelihood of causing the index stroke. Plaque characteristics, such as contrast enhancement, degree of stenosis, and morphology, were analyzed. Contrast enhancement was determined objectively after normalization with the pituitary stalk. A cutoff value for plaque-to-pituitary stalk contrast enhancement ratio (CR) was determined for optimal prediction of the presence of a culprit plaque. A revised stroke cause was adjudicated based on clinical and HR-VWI findings. RESULTS: A total of 344 cryptogenic strokes were analyzed, and 38 eligible patients were imaged with 7T HR-VWI. Intracranial atherosclerosis disease was adjudicated as the final stroke cause in 25 patients. A total of 153 intracranial plaques in 374 arterial segments were identified. Culprit plaques (n=36) had higher CR and had concentric morphology when compared with nonculprit plaques (P≤0.001). CR ≥53 had 78% sensitivity for detecting culprit plaques and a 90% negative predictive value. CR ≥53 (P=0.008), stenosis ≥50% (P<0.001), and concentric morphology (P=0.030) were independent predictors of culprit plaques. CONCLUSIONS: 7T HR-VWI allows identification of underlying intracranial atherosclerosis disease in a subset of stroke patients with suspected underlying vasculopathy but otherwise classified as cryptogenic. Plaque analysis in this population demonstrated that culprit plaques had more contrast enhancement (CR ≥53), caused a higher degree of stenosis, and had a concentric morphology.

Posterior cerebral artery stroke by reverse flow embolism in thoracic outlet syndrome - a case report.

BACKGROUND: Arterial thoracic outlet syndrome is a rare condition characterized by a subclavian artery pathology associated with a bone abnormality. It is rarely associated with thromboembolic stroke. The mechanism of cerebral embolism associated with thoracic outlet syndrome have rarely been demonstrated. We present here a fully studied case with a high probability of reverse flow embolism. CASE PRESENTATION: A 24-year-old man with a known arterial thoracic outlet syndrome presented with a right cerebral posterior artery brain infarction. An ultrasound examination depicted the compression of the right subclavian artery in the scalene defile with a post stenotic aneurysm and the presence of a floating thrombus in this aneurysm. There was a reverse flow during diastole in this aneurysm. Anticoagulation was carried out with the disappearance of the floating thrombus with no new clinical or brain MRI event. Corrective surgery of this thoracic outlet syndrome was performed one month after stroke. CONCLUSION: Very few cases of stroke in arterial thoracic outlet syndrome have been described with thorough dynamic vascular imaging. To our knowledge, this is the fourth reported case that advocates for a reverse flow embolism mechanism in stroke associated with thoracic outlet syndrome, and the first to realize an extensive ultrasound and doppler workup.

Response to Speech and Language Therapy According to Artery Involvement and Lesion Location in Post-stroke Aphasia.

PURPOSE: Aphasia is one of the most common complications after stroke and occurs in 21-38% of the patients during acute period. The present study aimed to investigate the response to speech and language therapy according to artery involvement and lesion location in patients with post-stroke aphasia. METHOD: The medical records of 107 patients with post-stroke aphasia (mean age, 58.8 ± 14.8 years) who were admitted to a single rehabilitation center for usual care after stroke were reviewed. Location of the ischemic lesion and involved artery was determined assessing the brain MRI of the patients. All the patients received 24 sessions speech and language therapy (3 days a week) as a part of 8-week rehabilitation program. Evaluation of the aphasia was performed with Gülhane Aphasia Test-2 (GAT-2) at baseline and at the end of the rehabilitation program. RESULTS: Baseline GAT-2 scores was significantly worse in patients with middle cerebral artery (MCA) involvement compared to patients with other artery involvements (p = 0.007). While the GAT-2 scores of patients with MCA involvement were improved significantly after speech and language therapy (p < 0.001), the changes in those with anterior cerebral artery (ACA) and posterior cerebral artery (PCA) involvements were not significant (p > 0.05). CONCLUSIONS: The present findings suggested that speech functions might be more affected in ischemic lesion of MCA and response to SLT might be better in patients with MCA involvement.

Bilateral posterior cerebral artery territory infarction in a SARS-Cov-2 infected patient: discussion about an unusual case.

In time of SARS-Cov2 pandemic, neurologists need to be vigilant for cerebrovascular complications of Covid-19. We present a case of bilateral occipito-temporal infarction revealed by a sudden cortical blindness with haemorrhagic transformation after intravenous thrombolysis in a diabetic patient infected by Covid-19. Differential diagnoses are discussed in front of this unusual presentation and evolution.