Basilar artery curvature increases the risk of posterior circulation infarction occurrence in patients without vertebrobasilar stenosis.

INTRODUCTION: Limited cross-sectional or case-control studies have identified the relationship between basilar artery (BA) curvature and posterior circulation infarction (PCI). This study aimed to identify the influence of BA curvature severity on the risk of PCI occurrence in patients without vertebrobasilar stenosis through a prospective cohort study. METHODS: In this study, we enrolled 171 patients with BA dolichosis but without vertebrobasilar stenosis. The BA geometric parameters were evaluated on MRA. The primary outcome was the occurrence of PCI, mainly referring to cerebellar and/or brainstem infarction. Cox proportional hazard models were used to detect possible predictors of PCI. RESULTS: Among them, 134 (78.4%) patients were diagnosed with BA curvature, including 124 with moderate curvature and 10 with prominent curvature. The defined PCI occurrence was observed in 32 (18.7%) patients with a median follow-up time of 45.6 months. Cox proportional hazard analysis showed that BA prominent curvature (HR = 6.09; 95% CI: 1.36-27.28; P = 0.018) significantly increased the risk of PCI occurrence, and bending length (BL) was also significantly associated with PCI occurrence, with the adjusted HR per 1-mm increase of BL of 1.09 (95% CI: 1.01-1.18; P = 0.040). In the subgroup analysis stratified by age, BA prominent curvature was highly associated with PCI occurrence in patients aged > 61 years (HR = 11.76; 95% CI: 1.21-113.90; P = 0.033). Additionally, good antiplatelet therapy adherence could significantly reduce the risk of PCI occurrence. CONCLUSION: BA curvature may increase the risk of PCI occurrence, especially in elderly patients with prominent curvature. Improving adherence to antiplatelet therapy can help reduce the risk of PCI occurrence.

Isolated pontine infarction versus pontine plus infarction: prevalence, pathogenic mechanism, and outcomes.

BACKGROUND: Pontine infarctions are often associated with extrapontine infarcts. We aimed to elucidate differences in clinical characteristics, mechanisms, and functional outcomes between isolated pontine infarction (IPI) and pontine plus infarction (PPI). METHODS: We studied patients with acute pontine infarction between January 2019 and August 2021 and divided them into IPI and PPI according to diffusion-weighted magnetic resonance image. Vertical locations were classified into rostral, middle, and caudal, and horizontal locations were categorized as basal/tegmental and unilateral/bilateral. Factors associated with poor 90-day outcome (modified Rankin scale 3-6) were analyzed. RESULTS: Among 241 patients, 170 (70.5%) had IPI and 71 (29.5%) had PPI. The most frequently observed extrapontine areas were cerebellar (59.1%), followed by posterior cerebral artery territory (45.1%). Mental status changes, sensory changes, and ataxia were more common, and motor dysfunction was less common in PPI patients. The PPI patients more often had rostral (P < 0.001), bilateral lesions (P < 0.001), and moderate/severe vascular stenosis and atrial fibrillation; therefore, large artery disease (LAD) and cardioembolism were more common stroke mechanisms (P < 0.001). In IPI patients, high initial National Institutes of Health Stroke Scale (NIHSS) (adjusted Odds ratio (OR) = 1.38; P = 0.001) and old age (aOR = 1.05; P = 0.049) were associated with poor functional outcome, whereas moderate/severe stenosis (Reference: no stenosis, aOR = 7.17; P = 0.014) and high initial NIHSS (aOR = 1.39; P = 0.006) were related to unfavorable outcomes in PPI patients. CONCLUSIONS: PPI patients more often had extensive pontine lesions, LAD and cardioembolism, and their outcome was more often influenced by underlying severe vascular diseases. These differences need to be considered in the prevention and therapeutic strategies.

Prospective investigation of cerebellar cognitive affective syndrome in a previously non-demented population of acute cerebellar stroke.

OBJECTIVE: In this prospective study, we aimed to investigate the presence and evolution of cerebellar cognitive affective syndrome in a cohort of isolated cerebellar stroke with no known cognitive or psychiatric impairment. We tried to distinguish the unconfounded effect of cerebellar lesions on neuropsychological processing. METHODS: After a meticulous exclusion procedure based on possible confounders, we recruited 14 patients and 13 age-matched healthy controls to the study, prospectively. All of the patients had a detailed initial neuropsychological assessment at the first week and a follow-up assessment at the 4th month after stroke. RESULTS: The prevalence of cognitive or behavioral-affective abnormalities in our cohort were 86% and 64% respectively. The patients exhibited mild and transient affective-behavioral abnormalities except for depressive symptoms that persisted in the subacute stage. They scored lower in general cognitive performance as revealed by mini mental test (p=0.001). Memory, executive functions, attention and working memory, central processing speed, and linguistic abilities were impaired (p<0.001; p=0.001; p=0.007; p=0.05; p<0.001 respectively). Improvement was evident only in memory domain of the cognitive functions in the subacute stage. Cognitive impairment was more likely with a medial or posterolateral infarct (p=0.014). Behavioral-affective abnormalities were not associated with a specific location in our cohort. Age seemed to negatively correlate with the recovery in general cognitive performance on the follow-up. CONCLUSIONS: These findings show that acute denervation of cerebellocortical projections leads to mild affective-behavioral abnormalities, and full-blown cerebellar cognitive affective syndrome is rare. However, cognition was significantly affected after an acute cerebellar infarct even in a previously healthy, non-demented pure population.

Multidisciplinary Treatments of True Posterior Inferior Cerebellar Artery Aneurysms: Single-Center Retrospective Study and Treatment Algorithm.

BACKGROUND: True posterior inferior cerebellar artery (PICA) aneurysms outside the vertebral artery-PICA region are rare, with approximately 30 cases reported in just a few papers; no treatment paradigm has been advocated. The objective of this study was to present detailed clinical features and outcomes for several treatments for true PICA aneurysms and suggest an algorithm for treatment strategies. METHODS: We retrospectively analyzed outcomes of patients treated for PICA aneurysms with microsurgical and endovascular treatments. We also investigated the influence of several factors on the modified Rankin Scale score. RESULTS: Cases with PICA aneurysms (n = 36) outside the vertebral artery-PICA region were identified angiographically. Aneurysm locations included anterior medullary (n = 7), lateral medullary (n = 10), tonsillomedullary (n = 4), telovelotonsillar (n = 12), and cortical (n = 3) segments of the PICA. Aneurysm morphology was as follows: dissecting: 22; fusiform: 6; and saccular: 8. On multivariate analysis, age (P = 0.028) and lack of vermian infarction (P =0.037) were associated with a significantly better prognosis. Prognosis was not significantly different for the 5 aneurysm locations and among the 4 treatment groups: clipping/coiling, trapping/parent artery occlusion, trapping/parent artery occlusion + bypass, and observation including external ventricular drainage. CONCLUSIONS: This study suggests that factors associated with significantly better prognosis include age, clip/coil treatments, and no vermian infarction complication. A treatment algorithm for true PICA aneurysms was supported according to pretreatment H and K grade, PICA segments, aneurysm morphology, and 3 types of ischemia linked to the brainstem, cerebellar hemisphere, or vermis.

A cohort study of isolated brainstem infarction based on head MR imaging and clinical findings.

OBJECTIVE: The prognosis of patients with isolated brainstem infarction (BSI) differs on an individual patient basis. This study was undertaken to analyze the influences of different imaging and clinical features with the prognosis of patients with BSI. METHODS: The study population was derived from a multicenter study of intracranial atherosclerosis in China. In the present study, 300 patients were selected who had experienced non-cardiogenic brain stem infarction within the prior 7 days. Evaluations included clinical characteristics, location and size of the brainstem infarction, and whether the infarction was located in multiple perforating branches of the brainstem. Poor prognosis was defined as the presence of disability within 1 year from the onset of disease. RESULTS: In total, 281 patients were followed up at 1 year post-infarction. Of these 281 patients, 84 (29.9%) exhibited disability at 1 year; these patients showed a median National Institutes of Health Stroke Scale score of 6 on admission. Multiple logistic regression analysis showed that patients with BSI located in the territory of multiple perforating arteries, who were discharged without administration of statins, showed a poor 1-year prognosis. CONCLUSION: Isolated BSI involving multiple perforating arteries, without statin medication at discharge, indicated poor prognosis for patients with BSI.

Infarto isquémico mesencefálico: síndrome de Weber / Ischemic mesencephalic infarction: Weber's syndrome

La enfermedad cerebrovascular constituye la tercera causa de muerte en la población adulta, la primera causa de discapacidad a escala mundial y la segunda causa de demencia, problema de salud actual relacionado con otras enfermedades crónicas no transmisibles. Se presenta un caso de un infarto isquémico mesencefálico aterotrombótico en una anciana de 77 años con la expresión clínica de un síndrome de Weber. El síndrome de Weber es uno de los síndromes cruzados o alternos de la clínica y la neurología por lesión peduncular. Es poco frecuente y a la vez, el más frecuente de los alternos de tronco encefálico(AU)

Cerebrovascular disease is the third leading cause of death in the adult population, the leading cause of disability worldwide and the second cause of dementia. It is a current health problem related to other chronic noncommunicable diseases. We present a case of atherothrombotic mesencephalic ischemic infarction in a 77-year-old woman with the clinical expression of Weber syndrome, which is a crossed or alternating clinical syndrome and neurology by pedicle injury. It is rare and, at the same time, the most frequent alternating brainstem(AU)

Non-alcoholic fatty liver disease is associated with stroke severity and progression of brainstem infarctions.

BACKGROUND AND PURPOSE: Non-alcoholic fatty liver disease (NAFLD) is closely correlated to visceral obesity, dyslipidaemia, insulin resistance and type 2 diabetes mellitus. We sought to assess the association between a specific stroke subgroup, brainstem infarctions (BSIs) and NAFLD. Furthermore, we evaluated whether NAFLD is an independent risk factor in patients with BSIs. METHODS: Non-alcoholic fatty liver disease was assessed in 306 patients with radiologically confirmed BSIs via liver ultrasound. Differences between patients with and without NAFLD were compared. Data associated with stroke severity and progression after admission were collected. RESULTS: Non-alcoholic fatty liver disease was found in 130 (42.5%) patients with acute BSIs; 58 (19.0%) had National Institutes of Health Stroke Scale scores >7 and 57 (18.6%) had progression after admission. Initial National Institutes of Health Stroke Scale scores, incidence of progression and stroke severity, and modified Rankin Scale scores at discharge were significantly higher in patients with NAFLD than in those without NAFLD. NAFLD was associated with stroke severity [Cox regression: hazard ratio (HR), 2.243; 95% confidence interval (CI), 1.254-4.013, P < 0.01]. This risk remained statistically significant after controlling for age, gender, diabetes mellitus and C-reactive protein (HR, 2.327; 95% CI, 1.252-4.324, P < 0.01). In addition, NAFLD was associated with progression (HR, 2.155; 95% CI, 1.201-3.865, P < 0.05) and remained significant after controlling for age, gender, diabetes mellitus, fibrinogen and C-reactive protein (HR, 2.378; 95% CI, 1.260-4.486, P < 0.01). CONCLUSIONS: These results suggest that NAFLD is a potential risk factor when evaluating the severity and progression of acute BSIs. This relationship is independent of classic risk factors and metabolic syndrome features.

Dolichoectasia and Small Vessel Disease in Young Patients With Transient Ischemic Attack and Stroke.

BACKGROUND AND PURPOSE: We evaluated whether basilar dolichoectasia is associated with markers of cerebral small vessel disease in younger transient ischemic attack and ischemic stroke patients. METHODS: We used data from the SIFAP1 study (Stroke in Young Fabry Patients), a large prospective, hospital-based, screening study for Fabry disease in young (<55 years) transient ischemic attack/stroke patients in whom detailed clinical data and brain MRI were obtained, and stroke subtyping with TOAST classification (Trial of ORG 10172 in Acute Stroke Treatment) was performed. RESULTS: Dolichoectasia was found in 508 of 3850 (13.2%) of patients. Dolichoectasia was associated with older age (odds ratio per decade, 1.26; 95% confidence interval, 1.09-1.44), male sex (odds ratio, 1.96; 95% confidence interval, 1.59-2.42), and hypertension (odds ratio, 1.39; 95% confidence interval, 1.13-1.70). Dolichoectasia was more common in patients with small infarctions (33.9% versus 29.8% for acute lesions, P=0.065; 29.1% versus 16.5% for old lesions, P<0.001), infarct location in the brain stem (12.4% versus 6.9%, P<0.001), and in white matter (27.8% versus 21.1%, P=0.001). Microbleeds (16.3% versus 4.7%, P=0.001), higher grades of white matter hyperintensities (P<0.001), and small vessel disease subtype (18.1% versus 12.4%, overall P for differences in TOAST (P=0.018) were more often present in patients with dolichoectasia. CONCLUSIONS: Dolichoectasia is associated with imaging markers of small vessel disease and brain stem localization of acute and old infarcts in younger patients with transient ischemic attack and ischemic stroke. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00414583.

Dorsal Medullary Infarction: Distinct Syndrome of Isolated Central Vestibulopathy.

BACKGROUND AND PURPOSE: The characteristics of infarctions restricted to the dorsal medulla have received little attention. This study aimed to define the distinct clinical features of dorsal medullary infarction. METHODS: Of the 172 patients with a diagnosis of medullary infarction at Seoul National University Bundang Hospital from 2003 to 2014, 18 patients with isolated dorsal medullary infarction were subjected to analyses of clinical and laboratory findings. RESULTS: All patients presented acute isolated vestibular syndrome with dizziness/vertigo and imbalance. Almost all patients (17/18, 94%) showed the signs from involvements of the vestibular nuclei, nucleus prepositus hypoglossi, or inferior cerebellar peduncle, which included direction-changing gaze-evoked nystagmus (n=12), negative head-impulse tests (n=8), skew deviation (n=7), central patterns of head-shaking nystagmus (n=6), and spontaneous nystagmus (n=2). Initial magnetic resonance imagings including diffusion-weighted images were negative in 7 patients (39%). Twelve patients (67%) showed a progression and developed additional neurological abnormalities, but the neurological outcomes were favorable. CONCLUSIONS: The presence of central vestibular signs allows bedside differentiation of isolated vestibular syndrome because of dorsal medullary infarction from acute peripheral vestibular disorders. Because initially false-negative magnetic resonance imagings and subsequent progression are frequent in dorsal medullary infarction, early recognition through scrutinized evaluation is important for proper managements.

Risk factors and etiological subtype analysis of brainstem infarctions.

OBJECTIVE: To evaluate the features of risk factors and etiological subtypes of brainstem infarctions (BSIs) patients in China. METHODS: One hundred and ninety-nine cerebral infarction patients with brainstem involvement were categorized into five groups according to Trial of Org 10172 in Acute Stroke Treatment classification: large artery disease (LAD), cardioembolism (CE), small vessel disease (SVD), stroke of other determined etiology (SOE) or stroke of undetermined etiology (SUE). The risk factors and percentage of the different etiological subtypes were assessed. RESULT: A total of 199 patients were enrolled in this study. The number and percentage of patients in SVD, LAD, SUE, CE and SOE were 77 (38.7%), 74 (37.2%), 25 (12.6%), 23 (11.6%) and 0, respectively. There were significantly different incidences of hypertension, diabetes and coronary heart disease (CHD) without atrial fibrillation (AF) among different stroke subtypes (P=0.006, P=0.002, P=0.016, respectively). Hypertension was more prevalent in LAD than in SVD and CE (P=0.001 and P=0.039, respectively) while the incidence of diabetes in LAD was higher than those in SVD and CE (P<0.001 and P=0.015, respectively). CHD without AF was more prevalent in CE than in SVD and LAD (P=0.044 and P=0.012, respectively). LAD was significantly associated with hypertension (OR=3.18, P=0.009) and diabetes (OR=2.84, P=0.003) in BSIs. CONCLUSION: The pattern of etiological subtypes of BSIs in China has its own characteristics. It might result from the features of risk factors in Chinese patients.

Insulin resistance and the risk of stroke and stroke subtypes in the nondiabetic elderly.

Insulin resistance, which plays a key role in the development of diabetes mellitus, is a putative modifiable risk factor for stroke. The aim of this study was to investigate if markers of insulin resistance were associated with risk of stroke in the general elderly population. This study was part of the large population-based Rotterdam Study and included 5,234 participants who were aged 55 years or older and stroke free and diabetes free at baseline (1997-2001). Fasting insulin levels and homeostasis model assessment for insulin resistance were used as markers for insulin resistance. Cox regression was used to determine associations between insulin resistance markers and stroke risk, adjusted for age, sex, and potential confounders. During 42,806 person-years of follow-up (median: 8.6 years), 366 first-ever strokes occurred, of which 225 were cerebral infarctions, 42 were intracerebral hemorrhages, and 99 were unspecified strokes. Fasting insulin levels were not associated with risk of any stroke, cerebral infarction, or intracerebral hemorrhage. Homeostasis model assessment for insulin resistance, which almost perfectly correlated with fasting insulin levels, was also not associated with risk of stroke or stroke subtypes. In conclusion, in this population-based cohort study among nondiabetic elderly, insulin resistance markers were not associated with risk of stroke or any of its subtypes.

Occurrence and clinicotopographical correlates of brainstem infarction in patients with diabetes mellitus.

BACKGROUND: The goal of the study was to clarify the association between diabetes mellitus (DM) and brainstem infarctions (BSIs) and to investigate the clinicotopographic characteristics of BSIs in patients with diabetes. METHODS: Data were retrospectively reviewed for 1026 consecutive patients admitted to our hospital because of acute cerebral infarctions from January 2004 to August 2010. Acute symptomatic BSIs were explored on radiologic images and classified into multiple infarctions with BSIs, multifocal BSIs, and monofocal BSIs. Isolated BSIs were further classified based on the vertical distribution into midbrain, pontine, and medullary infarctions, and on the horizontal distribution into anterior-dominant, posterior-dominant, and anterior/posterior BSIs. Neurologic symptoms of BSIs and clinical background were compared between DM and non-DM patients. RESULTS: The prevalence of BSIs was 2.6-fold higher (P < .0001) in DM patients. Logistic regression analysis including age, sex, smoking, previous stroke, atrial fibrillation, other cardiac diseases, hypertension, hyperlipidemia, and DM showed that DM was independently associated with BSIs (odds ratio [OR] 2.814; 95% confidence interval [CI] 1.936-4.090; P < .0001). Compared with non-DM patients, DM patients showed more frequent monofocal BSIs (P < .0001) and multifocal BSIs (P = .0296). Monofocal BSIs (n = 114) more frequently involved the pons (P < .0001) and medulla (P = .0212). Anterior-dominant BSIs (P < .0001) were more common in DM patients than in non-DM patients. Symptoms of BSIs included more frequent motor paresis (P = .0180) and less frequent diplopia (P = .0298) in DM patients than in non-DM patients. CONCLUSIONS: DM is important in the development of BSIs, and the associated clinical characteristics include more frequent motor paresis and less frequent diplopia.

Medial medullary infarction identified by diffusion-weighted magnetic resonance imaging.

OBJECTIVE: To elucidate the frequency and clinical profiles of patients with medial medullary infarction (MMI) identified by diffusion-weighted MRI (DWI). METHODS: We assessed the frequency, radiological findings, etiology and clinical features of MMI detected by DWI from our single-center registry of acute ischemic patients. RESULTS: Thirty patients (1.5% of 2,014 with ischemic stroke) had MMI, including isolated unilateral MMI in 26 patients. Lesions were located by DWI in the rostral medulla of 25 patients (83%). Culprit infarcts that were undetectable by DWI in 6 (38%) of 16 patients who were assessed within 24 h after onset were later confirmed as MMI. The major etiological mechanism was small artery occlusion (SAO; 19 patients) and the median initial National Institutes of Health Stroke Scale score was 4 (interquartile range: 3-4.75). The most frequent symptom was contralateral hemiparesis (27 patients). None of the patients fulfilled the classical Dejerine Triad. Twenty-two patients (73%) had a modified Rankin Scale score of ≤2 at 3 months. A patient developed transient ischemic attack within 3 months; none developed recurrent stroke. CONCLUSIONS: Rostral medullary infarction with mild neurological deficits resulting from SAO is relatively frequent. Because emergency DWI within 24 h could not detect MMI in one third of the patients, this type of infarction could be misdiagnosed as capsular/pontine lacunae or other neurological disorders.

Claude's syndrome associated with neurocysticercosis.

Claude's syndrome is a distinctive brainstem syndrome characterized by ipsilateral third cranial nerve palsy with contralateral hemiataxia and is due to an intrinsic or extrinsic lesion in the midbrain. We report a case of Claude's syndrome caused by neurocysticercosis infection. A 68 year-old Asian man was admitted to our hospital because of ataxia, left ptosis, and diplopia. Brain magnetic resonance imaging (MRI) showed a cystic lesion in the midbrain, which was surrounded by ring enhancement and peripheral edema. Neurocysticercosis infection was diagnosed by the cerebral spinal fluid study. The patient was treated with albendazole and steroids. A follow-up brain MRI three months later demonstrated the disappearance of a surrounding brain edema and rim enhancement. The most common cause of Claude's syndrome is cerebrovascular disease and malignancy. However, there is no report caused by neurocysticercosis infection. Therefore, if we encounter Claude's syndrome, we should consider neurocysticercosis infection as one of the etiologic factors.

The prevalence of thyrotoxicosis-related seizures.

BACKGROUND: Central nervous system dysfunction, such as hyperexcitation, irritability, and disturbance of consciousness, may occur in patients with thyrotoxicosis. There are also a few case reports of seizures attributed to thyrotoxicosis. The objective of the present study was to determine the prevalence of seizures that appeared to be related to the thyrotoxic state in patients with thyrotoxicosis. METHODS: We retrospectively determined the prevalence and clinical features of seizures in 3382 patients with hyperthyroidism. Among patients with seizures, we excluded those with other causes of seizures or a history of epilepsy. We did not exclude two patients in whom later work-up showed an abnormal magnetic resonance imaging, as their seizures resolved after they became euthyroid. RESULTS: Among the 3382 patients with hyperthyroidism, there were seven patients (0.2%) with seizures who met our criteria. Primary generalized tonic-clonic seizures occurred in four patients (57%), complex partial seizures with secondary generalized tonic-clonic seizures occurred in two patients (29%), and one patient had a focal seizure (14%). The initial electroencephalography (EEG) was normal in two patients (29%), had generalized slow activity in four patients (57%), and had diffuse generalized beta activity in one patient (14%). On magnetic resonance imaging, one patient had diffuse brain atrophy, and one had an old basal ganglia infarct. After the patients became euthyroid, the EEG was repeated and was normal in all patients. During follow-up periods ranging from 18 to 24 months, none of the patients had seizures. CONCLUSIONS: Hyperthyroidism is the precipitating cause of seizures in a small percentage of these patients. In these patients, the prognosis is good if they become euthyroid. The prevalence of thyrotoxicosis-related seizures reported here can be used in conjunction with the prevalence of thyrotoxicosis in the population to estimate the prevalence of thyrotoxicosis-related seizures in populations.

Basilar artery dolichoectasia is associated with paramedian pontine infarction.

BACKGROUND: Basilar artery (BA) dolichoectasia (dilatative arteriopathy) (BAD) causes arterial elongation and enlargement with subsequent hemodynamic changes leading to thrombosis, microembolization and brainstem compression. Little is known about the association between BAD and the pattern of pontine infarct in patients without BA stenosis. METHODS: We studied patients with isolated pontine infarcts recruited from a stroke registry. The patients with pontine infarction were divided into 2 groups based on the location of the lesion on magnetic resonance imaging as follows: paramedian pontine infarct (PPI) and lacunar pontine infarct (LPI). We compared the vascular findings and risk factors in the patients with the 2 types of infarcts. Using modified imaging criteria, we compared the following dolichoectatic components of the BA: (1) ectasia, (2) lateral displacement and (3) height. RESULTS: There were 96 patients (45 women, 51 men). Thirty-five patients had PPI and 61 had LPI. Ectasia of the BA was more frequent in the PPI group than in the LPI group (31.4 vs. 11.5%; p = 0.016). Ectasia of the BA was associated with an elevated odds ratio in the patients with PPI (odds ratio 5.80, 95% CI 1.66-20.21) by multivariate analysis. CONCLUSION: Ectasia of the BA other than elongation or angulation appears to contribute to the occurrence of PPI. These findings may be helpful in predicting certain types of stroke.

Endovascular surgery using stents for vertebral artery dissecting aneurysms and a review of the literature.

The treatment of dissecting aneurysms of the vertebral artery (VA) involving the posterior inferior cerebellar artery (PICA) or presenting with hypoplasia of the contralateral VA is controversial. We describe our experience with 4 ruptured and 2 unruptured VA dissecting aneurysms and discuss the efficacy of endovascular surgery using stents. All patients were male; their mean age was 50.7 years. According to World Federation of Neurological Surgeons (WFNS) grading, 3 of the ruptured aneurysms were grade V, the other was grade I. All patients were successfully treated using stents; in 5 we also coil-embolized the aneurysmal lumen. One aneurysm was treated by the placement of 2 stents covering the dissection site; there was a danger of aneurysmal rupture during coil embolization. No technical complications were encountered although one patient suffered minor rebleeding 5 days post-treatment. Delayed vasospasm occurred in 4 cases. According to the Glasgow Outcome Scale (GOS), at 3 months after treatment 2 patients had made a good recovery, one was moderately disabled, one suffered severe disability, and 2 had died. One death each was due to acute myocardial and brain stem infarction. Endovascular surgery using stents may be a useful treatment in patients in poor condition who manifest dissecting VA aneurysms involving the PICA or hypoplasia of the contralateral VA, especially in the acute period after rupture.

Sudden deafness related to posterior circulation infarction in the territory of the nonanterior inferior cerebellar artery: frequency, origin, and vascular topographical pattern.

AIMS: To investigate the frequency and origin of sudden deafness (SD) associated with the nonanterior inferior cerebellar artery (non-AICA) territory posterior circulation infarct(s), and the vascular topographical patterns of ischemic lesion associated with SD. METHODS: A total of 685 consecutive cases of vertebrobasilar ischemic stroke diagnosed by brain MRI from acute stroke registry were studied. RESULTS: Seven consecutive patients (1.0%) were identified as having SD as a symptom of non-AICA territory vertebrobasilar ischemic stroke. Audiological testing confirmed sensorineural hearing loss, predominantly cochlear in 4 patients and combined on the affected side cochlear and retrocochlear in 3 patients. Five patients had an isolated cerebellar infarct in the territory of the medial branch of the posterior inferior cerebellar artery and other 2 had infarct in the brainstem. In all, SD was on the side of infarct, as shown on brain MRI. Six patients had accompanied canal paresis to caloric stimulation on the side of SD. CONCLUSIONS: SD due to non-AICA territory infarction was mostly associated with infarct in the territory of the posterior inferior cerebellar artery. From the known variation of the anatomy of the internal auditory artery and results of audiovestibular evaluations, SD due to non-AICA territory infarct probably results from the damage to the inner ear.

Aetiopathogenesis and long-term outcome of isolated pontine infarcts.

BACKGROUND AND PURPOSE: Isolated pontine strokes cause characteristic neurological syndromes and have a good short-term prognosis. The aim of this study was to examine the long-term survival, cumulative recurrence rate and clinical handicap of patients with isolated pontine infarcts of different aetiology. METHODS: One hundred consecutive patients with an isolated pontine infarction were identified by imaging studies and evaluated prospectively. After extensive study, cases were classified according to the aetiopathogenetic mechanisms: stroke due to basilar artery branch disease (BABD), small-artery disease (SAD) and large-artery-occlusive disease (LAOD). During a mean follow-up period of 46 months, stroke presentation and initial course, early and long-term mortality, disability and recurrence were evaluated. RESULTS: BABD was the most frequent cause of isolated pontine ischaemia (43%), followed by SAD (34%) and LAOD (21%). Hypertension was the most prominent risk factor, especially among patients with SAD (94.1%). Neurological impairment on admission was more severe in the LAOD group, followed by BABD. After 1 month patients with LAOD had the highest cumulative mortality (14.3%, p = 0.026) and more severe disability (61.1%, p = 0.001). Five-year mortality rate was 20.6%, 14% and 23.8% in the SAD-, BABD- and in LAOD-group respectively (p = 0.776). Cumulative 5-year recurrence rate was 2.3 % for BABD, 14.3 % for LAOD, and 29.4 % for SAD (p = 0.011). CONCLUSIONS: Overall long-term survival of patients with isolated pontine infarcts is good. Initial differences regarding short-term outcome in infarctions of different aetiology resolve with time. Effective secondary prevention among SAD patients may limit stroke recurrence and positively influence long-term prognosis.

Lateral and medial medullary infarction: a comparative analysis of 214 patients.

BACKGROUND AND PURPOSE: No large-scale study has ever compared the clinical and radiological features of lateral medullary infarction (LMI) and medial medullary infarction (MMI). The aim of this study was to investigate them through the use of cooperatively collected cases. METHODS: Medical information on all patients from 1996 to 2000 with medullary infarction (MI) proven by brain MR images at 35 stroke centers in the Tohoku district, Japan, was collected, and their clinical and radiological features were analyzed. RESULTS: A total of 214 cases of MI were registered. They included 167 cases (78%) of LMI, 41 (19%) of MMI, and 6 (3%) of LMI plus MMI. The mean age of onset and the male-to-female ratio were 60.7 years and 2.7:1 in LMI and 65.0 years and 3.6:1 in MMI, respectively. The middle medulla was most frequently affected in LMI, and the upper medulla was most frequently affected in MMI. Dissection of the vertebral artery was observed in 29% of LMI and 21% of MMI. Prognosis, assessed by the Barthel Index, was favorable in both LMI and MMI. Diabetes mellitus was more frequently associated with MMI than with LMI. CONCLUSIONS: The present study surveyed a large number of MI cases and revealed that (1) the mean age of onset of MMI is higher than that of LMI, (2) the dissection of the vertebral artery is an important cause not only of LMI but also of MMI, and (3) diabetes mellitus is frequently associated with MMI.