Diffusion-weighted imaging at b1000 for identifying intracerebral hemorrhage: preliminary sensitivity, specificity, and inter-rater variability.

BACKGROUND: Noncontrast computed tomography (NCCT) is the gold standard to detect intracerebral hemorrhage (ICH) and ischemic stroke (IS) in patients presenting with acute focal syndromes. Diffusion-weighted magnetic resonance imaging (DW-MRI) obtained at b1000 is highly sensitive to identify acute IS but its sensitivity and specificity to detect ICH has not been systematically studied. METHODS: Patients with a diagnosis of ICH on NCCT were prospectively enrolled and underwent DW-MRI at b1000. Patients with suspected ischemia and a negative NCCT served as controls. All diffusion-weighted imaging (DWI) scans were evaluated blindly by 4 experienced raters. Sensitivity, specificity, and inter-rater variability of the DWI b1000 scans for detection of ICH were determined. RESULTS: In this preliminary pilot study, 15 patients with ICH and 17 patients with IS were included. All ICH lesions seen on NCCT showed a typical pattern on DW-MRI at b1000 with a hypointense core surrounded by a hyperintense rim. ICH volumes and size were similar on NCCT and MRI. All cases of IS were identified on the DWI scans but none were apparent on NCCT. The mean sensitivity and specificity of DW-MRI at b1000 for ICH were 94% and 93.5%, respectively, and the inter-rater variability for ICH detection on DWI was excellent (κ = .84). CONCLUSIONS: DW-MRI at b1000 has a diagnostic yield similar to NCCT for detecting ICH and superior to NCCT for detecting IS. Therefore, DW-MRI may be considered as the initial screening tool for imaging patients presenting with focal neurologic symptoms suggestive of stroke.

Primary Intracranial Hemorrhage: Characteristics, Distribution, Risk Factors, and Outcomes-A Comparative Study between Jewish and Arab Ethnic Groups in Northern Israel.

Background and purpose: This study aimed to investigate the differences in intracerebral hemorrhage (ICH) between Jews and Arabs residing in northern Israel, focusing on risk factors, hemorrhage volume, and functional outcome. Methods: A retrospective analysis was conducted utilizing a population-based registry to investigate intracerebral hemorrhage (ICH) characteristics, risk factors, and outcomes. The registry consisted of inpatients diagnosed with hemorrhagic stroke. Due to the wide variation in data on ICH characteristics and the limited availability of population-based data on predictors of ICH survival and functional outcomes, we collected retrospective data on all adult patients admitted to the Galilee Medical Center with a diagnosis of ICH. Data were obtained from the registry covering the period from 2013 to 2019. Ethnic differences and risk factors associated with intracranial hemorrhage (ICH) were examined within a diverse population of 241 patients, comprising 52.70% Jews (n = 127) and 47.30% Arabs (n = 114). Results: The results of this study revealed significant differences in age, obesity rates, and intracerebral hemorrhage (ICH) location between the two ethnic groups. Hypertension emerged as the most prevalent condition among ICH patients in both ethnic groups (76.70%), followed primarily by anticoagulant use (63.60%), dyslipidemia (60.70%), diabetes (44.60%), obesity (30.60%), smoking (24.60%), and a history of cardiovascular disease (21.80%). Furthermore, 20.90% of the patients had a history of previous cerebrovascular accidents (CVA). Arab patients with ICH were generally younger (62.90 ± 16.00 years) and exhibited higher rates of obesity (38.70%) compared to Jewish patients with ICH (70.17 ± 15.24 years, 23% obesity; p = 0.001, p = 0.013, respectively). Hemorrhage volume was identified as a crucial determinant of patient outcomes, with larger volumes associated with poorer Modified Rankin Scale (mRS) scores at discharge and higher mortality rates. Interestingly, patients without hypertension had higher hemorrhage volumes compared to those with hypertension. The extent of hemorrhage into the ventricles did not significantly correlate with mRS at discharge in our dataset. Conclusions: This study highlights significant differences in the characteristics and outcomes of intracranial hemorrhage (ICH) between Jews and Arabs in northern Israel. The findings reveal variations in age, obesity rates, and ICH location between the two groups. While hypertension was the most prevalent risk factor for both populations, other risk factors differed. Notably, hemorrhage volume emerged as a crucial prognostic factor, aligning with previously published data. These findings underscore the necessity for tailored approaches that consider ethnic-specific factors in the risk assessment, prevention, and management of ICH. Further research is warranted to elucidate the underlying mechanisms and develop interventions aimed at improving outcomes and enhancing healthcare practices in ICH management.

Vagal Nerve Activity and Short-Term Clinical Outcomes after Stroke: What Is Left May Not Be Right.

Stroke is a leading cause of death worldwide. Multiple factors influence the severity of stroke. Normal functional and biological differences seen between the hemispheres may also be related to stroke severity. In the present study, we examined the differences in the severity of stroke as a function of stroke side, and whether patients' vagal nerve activity moderated such differences. We included 87 patients with an ischemic stroke, whose medical records were retrospectively examined for background information (age, gender), stroke side and severity by NIHSS, length of stay in hospital, inflammation such as C-reactive protein, and vagal nerve activity. The vagal activity was indexed by patients' heart-rate variability (HRV), fluctuations in the intervals between normal heartbeats, derived from patients' ECG. Results revealed that patients with left-side stroke had significantly worse NIHSS scores (10.6) than those with right-sided stroke (7.6, p < 0.05). However, when dividing the sample into those with low versus high HRV (at the median), only when HRV was low, did patients with left-side stroke have a worse NIHSS score (10.9) compared to those with right-sided stroke (6.5, p < 0.05). In contrast, no differences in stroke severity were seen between left stroke (10.2) and right stoke (8.7, p > 0.05), when HRV was high. These results tended to remain the same when statistically controlling for age effects, which was related to NIHSS, but not to the stroke side. These findings suggest that patients with left-sided stroke may have more severe strokes than those with right-sided ones, but that adequate vagal nerve activity may protect against such differences. Possible mechanisms and suggestions for future directions are provided.

Atypical development of neurosyphilis mimicking limbic encephalitis.

A previously healthy 35-year-old man suffering from behavioral and mental deterioration for three months was referred to our facility. On admission, the patient was dysphasic and had tonic-clonic seizures. Neurological examination showed mental confusion, euphoric mood, mania, paranoia, and mild motor dysphasia. Magnetic resonance imaging (MRI) was performed twice but no abnormalities were revealed. His acute confusional state, elevated cerebrospinal fluid (CSF) protein, epileptic seizure and electroencephalogram showing intermittent frontal slowness were all suggestive of encephalitis. The patient was treated with acyclovir without significant improvement in his condition. Testing for herpes simplex virus and human immunodeficiency virus was negative. Limbic encephalitis was suspected and the patient was treated with intravenous immunoglobulin (IVIG) for five days. Venereal disease research laboratory and Treponema pallidum hemagglutination assay were both tested positive in serum and CSF. Neurosyphilis was diagnosed, and the patient received a 14-day course of penicillin G with gradual improvement. Anti-N-methyl-D-aspartate-receptor (anti-NMDAR) antibodies were positive in serum, confirming the presence of encephalitis. The atypical clinical presentation of neurosyphilis with symptomatology mimicking encephalitis and no MRI abnormalities made the diagnosis challenging. Coexistence of neurosyphilis with anti-NMDAR encephalitis has been reported only in one recent study. Our case demonstrates the importance of testing for syphilis in patients with unexplained neurologic deficits and suspected encephalitis.

Occlusion site does not impact outcome in patients with carotid stroke undergoing endovascular reperfusion.

BACKGROUND: It remains unclear whether occlusion site impacts outcome in patients with acute carotid artery occlusions. METHODS: Patients with acute carotid artery occlusion that underwent endovascular reperfusion treatments were prospectively enrolled. Patients with extracranial carotid bifurcation occlusions were compared with those with intracranial carotid-T-occlusions. Collected data included demographics, risk factor profile, and procedure-related variables. Neurological deficits were studied with the National Institutes of Health Stroke Scale and outcome was studied with the modified Rankin Score at day 90 after stroke and dichotomized into favorable (≤2) or unfavorable (>3). Recanalization status was studied with the thrombolysis in cerebral infarction scale. RESULTS: We included 51 patients (33 with extracranial bifurcation occlusion and 18 with intracranial T-occlusion). Patients with T lesions were significantly older (median 74 versus 56 years, P = 0.02), more frequently had atrial fibrillation (61% versus 18%; P = 0.005) and cardioembolism (78% versus 21% P = 0.001), smoked less often (6% versus 42%; P = 0.01), and less often required stent implantation (11% versus 48%; P = 0.015). However, neurological severity, other procedure and peri-procedure-related variables including recanalization rates and percentages of symptomatic hemorrhages did not differ between the groups. Mortality rates (24% versus 23%) and chances for favorable outcomes (33% versus 24%) did not significantly differ. On multivariate logistic regression analysis, occlusion location was not a significant modifier of outcome. CONCLUSIONS: Despite differences in stroke risk factors and treatments used between patients with extracranial bifurcation and intracranial T-occlusions, lesion location in itself does not influence outcome in patients with acute carotid artery occlusion treated with endovascular reperfusion.

Ischemic complications after tailored carotid artery stenting in different subpopulations with high-grade stenosis: feared but rare.

Although the procedural and postoperative safety profile of carotid artery stenting (CAS) has been steadily improving, many centers still recommend carotid endarectomy (CEA) over CAS. We assessed outcomes (procedural and postoperative stroke) following tailored CAS in a cohort of patients managed at a single academic medical center. Outcomes for patients with carotid artery stenosis treated from 2005-2013 with CAS were retrospectively reviewed. Stenosis was assessed with Doppler ultrasonography and/or CT angiogram, and angiography. Symptomatic and asymptomatic patients were dichotomized (based on the North American Symptomatic Carotid Endarterectomy Trial [NASCET] and the Asymptomatic Carotid Atherosclerosis Study [ACAS]). CAS technique was chosen based on angiographic and clinical characteristics; procedures were performed with/without pre-angioplasty, cerebral protection, and post-dilation. Endpoints were cumulative incidence of ipsilateral stroke, myocardial infarction, and death within 30 days (primary) or 12 months (secondary). Overall 249 patients (151 men/98 women; mean age 69.9 years) with 254 carotid stenoses were included; 148 lesions (58%) were asymptomatic, and 106 (42%) were symptomatic. CAS was successfully performed in all lesions. At 30 days, ipsilateral transient ischemic attack (TIA)/minor stroke was seen in 6/104 (5.8%) symptomatic patients and no asymptomatic patients; there was no myocardial infarction or ipsilateral major stroke. At 12 months, there was ipsilateral TIA/minor stroke in an additional 3/98 (3.1%) symptomatic and 1/127 (0.8%) asymptomatic patients, and major stroke in 1/98 (1%). The incidence of stroke after CAS compares favorably with rates reported after CEA. The majority of peri-procedural ischemic events following CAS are TIA/minor strokes causing only transient or minor functional impact; major disabling stroke is rare with current techniques.

Endovascular thrombectomy and stenting in the management of carotid fibromuscular dysplasia presenting with major ischemic stroke.

Fibromuscular dysplasia (FMD) affecting the internal carotid artery (ICA) is considered a benign condition; however, retinal and cerebral ischemic events may occur. We present a patient with carotid FMD presenting with a major ischemic stroke due to major embolic occlusion of the ICA in conjunction with a hemodynamic component caused by narrowing and beading of the lumen associated with FMD. The patient was successfully treated with intracranial stent-assisted thrombectomy followed by cervical ICA stenting that aimed to reconstruct and angioplasty the FMD-affected arterial segment. Recently, stent-based thrombectomy has emerged as the most effective endovascular option for the rapid revascularization of major intracranial occlusions; however, to our knowledge, its use in a rare case of FMD-associated major stroke has not yet been reported.

Should DWI MRI be the primary screening test for stroke?

Patients presenting with focal neurological symptoms may suffer from ischemic stroke, intracerebral hemorrhage, or stroke mimics. Such patients are usually screened with a noncontrast-enhanced computed tomography to rule out hemorrhage and to detect early signs of ischemia. However, the sensitivity of noncontrast-enhanced computed tomography for acute stroke is far inferior to that of diffusion-weighted magnetic resonance imaging and the latter is also very sensitive for identifying acute intracerebral hemorrhage. Most centers perform a magnetic resonance imaging stroke protocol that takes long to accomplish and may therefore delay therapy. Herein, we propose that a short diffusion-weighted imaging-only magnetic resonance imaging protocol can effectively differentiate ischemic stroke from intracerebral hemorrhage and stroke mimics and could therefore be used as the first line screening test for stroke. Adopting such a screening strategy will result in increased diagnostic accuracy and avoidance of unnecessary treatment of stroke mimics with thrombolysis but may come at the increased cost of performing a magnetic resonance imaging at the emergency department. Whether such a strategy will be cost effective or not remains to be tested in future studies.

Is vascular imaging valuable prior to administration of intravenous tissue plasminogen activator?

Our goals were to explore whether performing computerized tomography angiography (CTA) prior to administration of tissue plasminogen activator (tPA) delays treatment and impacts outcome in patients with proximal middle cerebral artery occlusions (pMCAO). Patients with pMCAO with a National Institutes of Health Stroke scale (NIHSS) score >10 were identified from a prospective Stroke Registry. Patients underwent multi-parametric imaging studies whenever possible. Patients who underwent CTA were compared to those who only had non-contrast CT scan. Disability was measured with the modified Rankin Scale. Logistic regression was used to determine outcome modifiers. We included 73 patients (median age 73 years, 52% men) with moderate-severe stroke (median admission NIHSS 14). Of those, 44 underwent CTA and 29 did not. There were no differences between the groups in risk factor profile or baseline characteristics including stroke severity and door to needle, door to imaging or imaging to treatment times. At 90 days post-stroke there were no statistically significant differences in outcomes between the groups. On multivariate analysis, performing CTA had no impact on the chance of obtaining favorable outcome. In conclusion, CTA does not have a major impact on outcome in patients with pMCAO treated with tPA. Therefore, performing CTA should be considered on an individual basis prior to administration of tPA.