Intrinsic stenosing and occlusive pathologies of the vertebral artery: A narrative review

Intrinsic pathologies of the vertebral arteries, such as atherosclerosis, dissection, fibromuscular dysplasia, radionecrosis and vasculitis, are important causes of vertebrobasilar insufficiency and cerebrovascular events. This review focuses on non-aneurysmal intrinsic stenosing and occlusive pathologies, covering their epidemiology, diagnosis, and treatment options. It also provides a detailed summary of key clinical presentations and syndromes, including an in-depth examination of lateral medullary syndrome, historically known as Wallenberg's syndrome, which is arguably the most emblematic condition resulting from vertebral artery involvement and is depicted in an illustrative cartoon.

Brain-Computer Interfaces for Communication in Patients with Disorders of Consciousness: A Gap Analysis and Scientific Roadmap

BACKGROUND

We developed a gap analysis that examines the role of brain-computer interfaces (BCI) in patients with disorders of consciousness (DoC), focusing on their assessment, establishment of communication, and engagement with their environment.

METHODS

The Curing Coma Campaign convened a Coma Science work group that included 16 clinicians and neuroscientists with expertise in DoC. The work group met online biweekly and performed a gap analysis of the primary question.

RESULTS

We outline a roadmap for assessing BCI readiness in patients with DoC and for advancing the use of BCI devices in patients with DoC. Additionally, we discuss preliminary studies that inform development of BCI solutions for communication and assessment of readiness for use of BCIs in DoC study participants. Special emphasis is placed on the challenges posed by the complex pathophysiologies caused by heterogeneous brain injuries and their impact on neuronal signaling. The differences between one-way and two-way communication are specifically considered. Possible implanted and noninvasive BCI solutions for acute and chronic DoC in adult and pediatric populations are also addressed.

CONCLUSIONS

We identify clinical and technical gaps hindering the use of BCI in patients with DoC in each of these contexts and provide a roadmap for research aimed at improving communication for adults and children with DoC, spanning the clinical spectrum from intensive care unit to chronic care.

Intima-Media Thickness and Pulsatility Index of Common Carotid Arteries in Acute Ischaemic Stroke Patients with Diabetes Mellitus

Ultrasonographic parameters such as the common carotid artery (CCA) pulsatility index (PI) and CCA intima-media thickness (IMT) have been associated with an increased mortality and risk of recurrent stroke, respectively. We hypothesized that these ultrasonographic parameters may be useful for monitoring diabetic patients after an acute stroke. We analysed retrospective data of consecutive acute ischaemic stroke patients from the ASTRAL registry who underwent pre-cerebral ultrasonographic evaluation within 7 days of symptom onset. We compared clinical, demographic, radiological and ultrasonographic parameters in diabetic versus non-diabetic patients (univariable and multivariable analyses) and the association of these parameters with CCA PI and CCA IMT. We analysed 1507 carotid duplex ultrasound examinations from patients with a median age of 74 years. Cardiovascular co-morbidities, including hypertension, hypercholesterolemia, obstructive sleep apnoea syndrome, higher body-mass index (BMI) and peripheral artery disease, were associated with diabetes mellitus (DM). Diabetics were more often under antiplatelet therapy and had atrial fibrillation at admission. Diabetic patients showed an increased CCA PI and IMT in line with more atherosclerotic changes on acute CTA compared to non-diabetic patients. Taking IMT as the dependent variable in a second analysis, DM, higher age, hypertension, smoking and CCA PI were associated with higher IMT. Taking CCA PI as the dependent variable in a third analysis, DM, higher age and higher NIHSS at admission were associated with higher CCA PI values. Increased IMT was also associated with higher PI. We show that CCA PI and IMT are higher in diabetic patients in the first week after an initial stroke.

Preconditioning by Preceding Ischemic Cerebrovascular Events

Background Emerging yet contrasting evidence from animal and human studies associates ischemic preconditioning with improvement of subsequent stroke severity, although long-term outcome remains unclear. The purpose of this study was to analyze how preceding cerebral ischemic events influence subsequent stroke severity and outcome. Methods and Results Data for this retrospective cohort study were extracted from ASTRAL (Acute Stroke Registry and Analysis of Lausanne). This registry includes a sample of all consecutive patients with acute ischemic strokes admitted to the stroke unit and/or intensive care unit of the Lausanne University Hospital, Switzerland. We investigated associations between preceding ischemic events (transient ischemic attacks or ischemic strokes) and the impact on subsequent stroke severity and clinical improvement within 24 hours, measured through National Institute of Health Stroke Scale, as well as 3-month outcome, determined through a shift in the modified Rankin Scale. Of 3530 consecutive patients with ischemic stroke (43% women, median age 73 years), 1001 (28%) had ≥1 preceding cerebral ischemic events (45% transient ischemic attack, 55% ischemic stroke; 31% multiple events). After adjusting for multiple prehospital, clinical, and laboratory confounders, admission stroke severity was significantly lower in patients preconditioned through a preceding ischemic event, but 24-hour improvement was not significant and 3-month outcome was unfavorable. Conclusions Preceding ischemic events were independently associated with a significant reduction in subsequent stroke severity but worsened long-term clinical outcome. These results, if confirmed by future randomized studies, may help design neuroprotective strategies. The unfavorable effect on stroke outcome is probably a consequence of the cumulative disability burden after multiple ischemic events.

Abstract TP421: Ischemic Preconditioning From Preceding Cerebrovascular Events in Stroke Patients

Introduction: Preconditioning improves acute ischemic stroke (AIS) outcomes in animals and possibly in humans. The influence of a preceding ischemic event (PIE), such as a TIA or AIS occurring at different intervals, sites and for different durations, needs to be studied in humans.

Hypothesis: We aimed to identify whether a PIE can have a preconditioning effect on a subsequent AIS.

Methods: Using consecutive AIS from the ASTRAL registry we determined demographics, risk factors, past medical history,stroke mechanism,PIE and other features that were associated with initial stroke severity measured by NIHSS. We used a multivariate linear regression model with NIHSS as the dependent variable to compare groups with and without PIE.

Results: Of 3501 consecutive AIS patients (43% females, median age 73 y), 996 (28.4%) had preceding PIEs (15.7% TIA, 12.9% ischemic stroke, 2.4% retinal ischemia, 8.8% multiple events). There were 162 acute PIE in the preceding 24 h, and 94 subacute PIE up to 7 d before the stroke, respectively with a median delay between the PIE and the subsequent stroke of 180 days.Results of the adjusted multivariate regression analysis are shown as forest plots below.

Conclusions: In patients with AIS, we found an independent association between lesser stroke severity and PIE, suggesting a possible beneficial role of ischemic preconditioning in stroke in humans. The effect of timing, severity,location of PIE and long-term outcome of such patients needs to be analyzed in further studies.

Beauty parlor stroke revisited: An 11-year single-center consecutive series

BACKGROUND

Hairdresser-related ischemic cerebrovascular events (HICE) are attributed to compression of vertebral arteries or cervical artery dissections. We determined their frequency, mechanisms, localization and outcome in a pre-specified study.

METHODS

We prospectively collected ischemic strokes and transient ischemic attacks occurring in relation to a hairdresser visit from 2002 to 2013, using consecutive data from an ischemic stroke registry (ASTRAL). HICE were compared to all other acute ischemic strokes in ASTRAL.

RESULTS

We identified 10 HICE (9 strokes and 1 transient ischemic attack). Age and anterior-posterior distribution were similar with a significantly higher rate of females (90% vs. 43%, p = 0.02) in the HICE group compared to ASTRAL. Patients with HICE had significantly lower incidence of hyperlipidemia (30% vs. 73%) and diabetes (0% vs. 19%). The mechanisms of HICE were diverse: carotid artery dissection (n = 2), cardiac (n = 2), lacunar (n = 2), other determined (n = 2) and unknown etiology (n = 2). Two HICE with atherosclerotic intracranial disease were possibly caused by acute hemodynamic changes related to systemic hypotension during hot air hair drying. Unadjusted favorable outcome at three months seemed to be better in HICE (90% vs. 57%), and 12-month mortality and recurrences were similar.

CONCLUSIONS

HICE may occur frequently in females without a predilection for the posterior circulation. Although some HICE may occur by chance (pseudo-HICE), hairdresser visits may have a causal role in some cases, including cervical artery dissection or hemodynamic compromise related to pre-existing arterial disease (true HICE). Available data are insufficient for specific preventive recommendations.

CTP in Transient Global Amnesia: A Single-Center Experience of 30 Patients

BACKGROUND AND PURPOSE

Medial temporal lobe abnormalities on DWI and functional imaging are occasionally observed in patients with transient global amnesia. We used CTP to study these patients during or briefly after resolution of their amnesic syndrome.

MATERIALS AND METHODS

From 2002 onward, patients satisfying clinical criteria for transient global amnesia who underwent CTP were included. Patients with additional clinical features suggesting transient ischemic attack or stroke and those with an ischemic lesion on subsequent DWI were excluded. If deemed necessary by the clinician, DWI was performed within 10 days.

RESULTS

Thirty patients with transient global amnesia underwent CTP at a median latency of 5.9 hours (interquartile range, 4.3-9.7 hours) after symptom onset. All findings, except for those in 1 patient, were normal, including those in the 14 patients with well-imaged hippocampi. In the patient with abnormal findings, CTP and PWI showed hypoperfusion in both lentiform nuclei extending into the insulae, with normalization on the repeat CTP 6 days later. In 10 patients, DWI was performed at a median latency of 2 days (interquartile range, 0-9 days). Of these, 2 showed punctate hippocampal lesions, often seen in transient global amnesia. In 2 patients excluded because of mildly atypical transient global amnesia and ischemic lesions on subsequent DWI, acute CTP findings were also normal.

CONCLUSIONS

Patients with transient global amnesia had normal CTP findings in the acute phase with the exception of 1 patient with transient hypoperfusion in both basal ganglia. If imaging is performed for typical and atypical transient global amnesia, DWI should be the preferred method.

Portal Vein Embolization Followed by Liver Resection versus Liver Resection Alone: a Comparison of Liver Regeneration Dynamics

BACKGROUND/AIMS

Portal vein embolization (PVE) is an accepted procedure, which, by redirecting portal vein flow toward specific hepatic segments, is able to pre-operatively increase the volume of the future liver remnant (FLR). The consequent reduction of liver dysfunction risk enables to extend the number of pa tients eligible for major hepatic resection. This study aims at comparing liver regeneration dynamics and long-term volumetric recovery after major hepatic re section preceded by PVE versus major hepatic resec tion not preceded by PVE.

METHODOLOGY

Data from 24 consecutive patients who underwent PVE prior to major hepatic resection were collected and compared to 24 consecutive patients who underwent major hepatic resection, but on whom PVE was not performed.

RESULTS

A significant growth of the FLR was observed after PVE. The liver remnant underwent a further regeneration burst after resection, with long-term volumetric recovery rates around 85% of the estimated total liver volume, similar to those observed for the control group and to those previously documented in the relevant literature.

CONCLUSION

PVE gives a first impulse to liver regeneration before liver resection without compromising further regeneration after resection, resulting in long-term volumetric recovery rates similar to those known for regeneration after liver resection without prior PVE.