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result(s) for
"Schaafsma, Joanna"
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Stroke endovascular thrombectomy related subarachnoid hyperdensity: incidence, predictive factors, and a proposed sub-classification
2025
BackgroundSubarachnoid hyperdensity (SAH) after endovascular thrombectomy is a well-known phenomenon. Nevertheless, the clinical significance and natural history of this phenomenon is not well described. In addition, we test previously postulated hypotheses of distal occlusions sites and antithrombotic use to SAH prevalence and extent.MethodsWe performed a retrospective analysis of all patients presenting with acute stroke and treated by endovascular thrmbectomy in our tertiary center January 2016 and February 2021. Only patients who underwent CT scan of the brain within 24 h after procedure were included.Results394 patients were included in this study. SAH after EVT was evident on CT in18.3% of those. Most of these (10.7%), had non-resolving hyperdensity (persistent SAH) on follow up imaging. A minority (2.6%) had resolving hyperdensity (transient SAH). Only 2% had a combination of subarachnoid hyperdensity and intracerebral hemorrhage (SAH + ICH). Transient and persistent SAH were associated with good functional and imaging outcomes as compared to SAH + ICH patients. Older age, large infarct size, stentretriever use and partial recanalization were correlated with SAH + ICH. Distal occlusions and distal vessel angulations resulting in higher traction potential were more prevalent in persistent SAH group. Higher number of thrombectomy passes was correlated with the extent of persistent SAH. Transient SAH group did not show statistically significant demographic or procedural trends.DiscussionWe propose therefore a distinct classification of the post thrombectomy SAH subtypes and discuss the putative pathophysiological mechanisms of the three distinct phenomena and their predictive factors.
Journal Article
Haemorrhagic stroke and brain vascular malformations in women: risk factors and clinical features
2024
Haemorrhagic stroke is a severe condition with poor prognosis. Biological sex influences the risk factors, presentations, treatment, and patient outcomes of intracerebral haemorrhage, aneurysmal subarachnoid haemorrhage, and vascular malformations. Women are usually older at onset of intracerebral haemorrhage compared with men but have an increased risk of aneurysmal subarachnoid haemorrhage as they age. Female-specific factors such as pregnancy, eclampsia or pre-eclampsia, postmenopausal status, and hormone therapy influence a woman's long-term risk of haemorrhagic stroke. The presence of intracranial aneurysms, arteriovenous malformations, or cavernous malformations poses unique clinical dilemmas during pregnancy and delivery. In the absence of evidence-based guidelines for managing the low yet uncertain risk of haemorrhagic stroke during pregnancy and delivery in women with vascular malformations, multidisciplinary teams should carefully assess the risks and benefits of delivery methods for these patients. Health-care providers should recognise and address the challenges that women might have to confront when recovering from haemorrhagic stroke.
Journal Article
Sex Differences in Functional Outcomes Following Endovascular Treatment for Acute Ischemic Stroke
by
Momen, Amirah I.
,
Rac, Valeria
,
Francis, Troy
in
Brain Ischemia - surgery
,
Chronic obstructive pulmonary disease
,
Comorbidity
2023
Sex disparities have been reported across many aspects of acute ischemic stroke (AIS) care; however, there is a relative paucity of research examining sex differences in outcomes following endovascular treatment (EVT). Some studies report worse functional independence for females following EVT. Few, if any of these studies account for differences in age, baseline function, and comorbidity burden. This retrospective cohort study aimed to assess for sex differences in functional outcomes following EVT by comparing 90-day modified Rankin Scale (mRS) of males and females while controlling for baseline function and comorbidity burden.
Baseline demographic and clinical data, and stroke severity were compared for 230 consecutive patients undergoing EVT for AIS between October 2014 and July 2019 at a tertiary stroke centre in Toronto, Canada. Effect of sex on likelihood of functional independence post-EVT was assessed using regression analysis with and without correction for age, baseline mRS, and Charlson Comorbidity Index (CCI).
Females undergoing EVT for AIS were older (75 ± 13 vs. 66 ± 15,
< 0.0001), with worse clinical and functional baselines. Unadjusted, males were more functionally independent (90-day mRS < 3) [OR = 1.831, 95%CI 1.082-3.098]. After controlling for age, baseline mRS and CCI, there was no difference between groups [OR 1.21, 95%CI 0.61-2.37].
This study provides evidence that prior findings of sex disparities in function after EVT may be accounted for by differences in age, baseline clinical status and functional independence between males and females when a comprehensive measure of comorbidity burden is utilized.
Journal Article
Comparison of multimodal CT scan protocols used for decision-making on mechanical thrombectomy in acute ischemic stroke
by
Khumtong, Rujimas
,
Krings, Timo
,
Pikula, Aleksandra
in
Aged
,
Angiography
,
Cerebral Angiography - methods
2020
Purpose
Different CT-based protocols are being used in acute ischemic stroke. We aimed to assess the added value of delayed-phase CT angiography (CTA) and CT perfusion (CTP) to a basic protocol using non-contrast computerized tomography (NCCT) with arterial-phase CTA in patient selection for mechanical thrombectomy.
Methods
We retrospectively included consecutive acute ischemic stroke patients with a symptomatic intracranial arterial occlusion between January 2015 and November 2016 who underwent NCCT, arterial and delayed-phase CTA, and CTP. These imaging studies were grouped into five protocols: (1) NCCT and arterial-phase CTA; (2) NCCT, arterial-phase CTA, and CTP; (3) NCCT, arterial- and delayed-phase CTA; (4) NCCT, arterial- and delayed-phase CTA, and CTP; and (5) NCCT and delayed-phase CTA. Two interventional neuro-radiologists independently decided on mechanical thrombectomy for each patient based on the protocols. They reached consensus for discrepant decisions. We assessed the raters’ confidence level, inter-rater agreement, and compared treatment decisions for the different protocols.
Results
We included 73 patients (44% male, mean age 74). The inter-rater agreement was substantial for protocols with three or more modalities (
ҡ
= 0.613–0.704) and moderate for two-modality protocols (
ҡ
= 0.506–0.529). The highest agreement and confidence level was achieved for the combination of NCCT, arterial-phase CTA, and CTP. Adding CTP to NCCT and arterial-phase CTA resulted in a 10% increase of recommendations for mechanical thrombectomy and adding delayed-phase CTA resulted in a 4% increase. These management changes did not reach statistical significance (
p
= 0.07;
p
= 0.25, respectively).
Conclusion
Adding CTP and/or a delayed-phase CTA to NCCT with arterial-phase CTA improves the decision-maker’s confidence level and creates a trend towards a lower threshold for mechanical thrombectomy.
Journal Article
Impact of the COVID-19 Pandemic on Stroke Subtype Presentation in Patients Without COVID-19 Infection
by
Williams, Janice
,
Francis, Troy
,
Pikula, Aleksandra
in
Alcohol
,
Atherosclerosis
,
Best practice
2024
It is unknown if the COVID-19 pandemic and public health measures had an immediate impact on stroke subtypes and etiologies in patients not infected with COVID-19. We aimed to evaluate if the proportion of non-COVID-19-related stroke subtypes (ischemic vs. hemorrhagic) and etiologies (cardioembolic, atherosclerosis, small vessel disease, and others) during the pandemic's first wave were different from prepandemic.
For this retrospective cohort study, we included patients without COVID-19 with ischemic or hemorrhagic stroke at two large Canadian stroke centers between March-May 2019 (prepandemic cohort) and March-May 2020 (pandemic cohort). Proportions of stroke subtypes and etiologies were compared between cohorts using chi-square tests.
The prepandemic cohort consisted of 234 stroke patients and the pandemic cohort of 207 stroke patients. There were no major differences in baseline characteristics. The proportions of ischemic versus hemorrhagic stroke were similar (ischemic stroke: 77% prepandemic vs. 75% pandemic; hemorrhagic stroke:12% prepandemic vs. 14% pandemic;
> 0.05). There were no differences in etiologies, except for a decreased proportion of ischemic stroke due to atherosclerosis in the pandemic cohort (26% prepandemic vs. 15% pandemic; difference: 10.6%, 95%CI: 1.4-19.7;
= 0.03). Notably, during the pandemic, the cause of ischemic stroke was more often unknown because of incomplete work-up (13.3% prepandemic vs. 28.2% pandemic, difference: 14.9%, 95%-CI: 5.7-24.2;
= <0.01).
In this study, the pandemic had no clear effect on stroke subtypes and etiologies suggesting a limited impact of the pandemic on stroke triggers. However, the shift from atherosclerosis toward other causes warrants further exploration.
Journal Article
Radiological Outcome of Middle Meningeal Artery Embolization in Relation to Chronic Subdural Hematoma Cause and Architecture
2024
Background/Objectives: MMAE (middle meningeal artery embolization) has emerged as a potential effective treatment for cSDH (chronic subdural hematoma). In this study, MMAE efficiency with regards to cSDH cause and architecture was explored. The comparability of cSDH thickness and volume as parameters for cSDH pre- and post-MMAE assessment was also analyzed. Methods: In this retrospective cohort study, 52 consecutive cSDH patients treated with MMAE in a single tertiary center were included. The cohort was divided into two group pairs pertaining to cSDH cause (spontaneous or traumatic) and cSDH architecture (non-mature or mature). The radiological outcome was compared in each group before and after MMAE and between each group pair using CT imaging. A correlation analysis between cSDH thickness and volume before and after MMAE was also performed. Results: A statistically significant positive linear association between cSDH thickness and volume at admission and at each follow-up interval (1–3, 3–6, 6–12 months) was noticed. cSDH thickness and volume reduction in each group was statistically significant, except for a traumatic cSDH volume reduction at 6–12 months. There was no statistically significant difference between each group pair in the cSDH thickness and volume reduction difference at all the follow-up intervals. Conclusions: A comparable efficiency of MMAE may be achieved in non-mature and mature as well as in spontaneous and traumatic cSDH, with an advantage for spontaneous cSDH at 6–12 months follow-up compared to traumatic cSDH. Traumatic cSDH may require a relatively long-term follow-up post-MMAE. cSDH thickness and volume, as parameters for pre- and post-MMAE cSDH evaluation, appear similar.
Journal Article
Assessment of Inter-Reader Reliability of Fazekas Scoring on Magnetic Resonance Imaging of the Brain in Adult Patients with Sickle Cell Disease
by
O’Cearbhaill, Roisin M.
,
Haughey, Aoife M.
,
Padilha, Igor Gomes
in
Anemia
,
Blood diseases
,
Brain research
2025
Background/Objectives: Cerebral white matter disease is a common finding in patients with sickle cell that has been linked to cognitive impairment. However, there is no standardized approach for quantification of the cerebral disease burden. The Fazekas score is widely used to quantify the burden of white matter disease in chronic small vessel disease. However, its utility in sickle cell disease, specifically the inter-rater variability, has not been established. Methods: A patient cohort was compiled for the purpose of a research ethics board (REB)-approved retrospective study of adult patients with sickle cell disease, each of whom underwent MRI/MRA between the years 2017 and 2019. A total of 90 such patients were captured. All MRI/MRA studies were performed on three Tesla MRIs. Two independent neuroradiologists assessed the axial FLAIR MRI brain sequence (see image 1) for each of the 90 patients, with the sole focus of assigning a Fazekas score (0–3) to each study as a means of quantifying the burden of ischemic white matter lesions. The neuroradiologists were blinded to the scoring assigned by their counterpart and to the clinical information. After the initial assessment was completed, studies with discrepant Fazekas scores were documented and discussed by both readers. A consensus Fazekas score was then assigned to each of these studies. Results: Cohen’s weighted kappa was used as a measure of agreement between readers. The expected agreement was 74.65%, with an observed agreement of 94.44% between readers, with a kappa of 0.7808. Conclusions: We conclude on the basis of our study that there is good inter-reader reliability of Fazekas scoring on axial FLAIR MRI brain sequence in patients with sickle cell disease. The Fazekas is a promising measure that could easily be integrated in systematic evaluation of cerebrovascular lesions of adults with sickle cell disease.
Journal Article
The Impact of Revascularization Surgery on Headaches in Association with Cerebrovascular Reactivity in Patients with Moyamoya Angiopathy
by
Radovanovic, Ivan
,
Schaafsma, Joanna D.
,
Hendriks, Eef J.
in
Analgesics
,
Brief Report
,
Carbon dioxide
2024
Background/Objectives: Headaches in Moyamoya angiopathy are common but poorly understood. We aimed to investigate if headaches in Moyamoya angiopathy improve after revascularization surgery and whether this is associated with improvement in cerebrovascular reactivity on MRI (CVR-MRI). Methods: We included consecutive adult patients with Moyamoya angiopathy who had chart data on headaches, CVR-MRI, and underwent extracranial–intracranial bypass surgery between January 2010 and September 2022 at a tertiary neurovascular referral center. Clinical and CVR-MR imaging data of all patients were collected through systematic chart review, complemented by standard-of-care headache questionnaires from patients who were operated between 2018 and 2022. We evaluated headache features and explored the association between headaches and CVR before and after revascularization surgery. Results: Fifty-nine patients were included (mean age 47 ± 14 years, 43 females (73%)); among them, 41/59 (69%) reported headaches pre-surgery. Headache improved in 28/41 (68%) patients after revascularization surgery with a reduction in pain severity (median VAS-score from 5/10 to 2.5/10; p = 0.002), analgesic use (from 84% to 40%; p = 0.007), and sick leave (from 60% to 16%; p < 0.001). Improvement in headaches was associated with improvement in CVR (OR 5.3; 95% CI: 1.2–23.5) and sick leave reduction (OR 1.4; 95% CI: 1.6–121.4). Conclusions: Headaches in Moyamoya angiopathy are common and disabling. They may improve in most patients after revascularization surgery and seem to be associated with improvement in CVR, supporting the hypothesis of a potential vascular origin of the headaches.
Journal Article
Sex differences and possible applications of artificial intelligence in saccular unruptured intracranial aneurysms. A narrative review
by
Jensen, Adelaide
,
Schaafsma, Joanna D
,
Julie Novakova Martinkova
in
Aneurysms
,
Artificial intelligence
,
Carotid arteries
2024
Saccular unruptured intracranial aneurysm (UIA) refers to the abnormal bulging of an intracranial artery wall. UIAs are quite prevalent in the general population, affecting approximately 3% of individuals. Females have a significantly greater risk of UIA development, growth, and rupture compared to males, the reasons for which are not yet well understood. The female-to-male prevalence ratio of UIAs is as high as 2.2:1 in populations over 50 years old. This review offers an overview of the current understanding of sex influences in UIAs. We highlight the potential underlying mechanisms that may contribute to such sex influences, including the effects of reproductive aging and hormonal fluctuations on cerebral arteries and inflammation. Additionally, we delve into the role of artificial intelligence in addressing the knowledge gaps and clinical challenges associated with sex-specific UIA detection and management, highlighting the possibility for new AI models to integrate sex considerations in their development and applications. Gaining insight into sex differences in UIAs and harnessing the power of AI technologies can improve risk assessment, personalized treatment approaches, and patient health outcomes.
Journal Article
Automated CT Perfusion Imaging Versus Non-contrast CT for Ischemic Core Assessment in Large Vessel Occlusion
by
Hilditch, Christopher
,
Lenck, Stephanie
,
Nicholson, Patrick
in
Aged
,
Arterial Occlusive Diseases - complications
,
Arterial Occlusive Diseases - diagnostic imaging
2020
Purpose
There is increasing use of automated computed tomography perfusion (CTP) to aid thrombectomy decision in emergent large vessel occlusion. It is important to understand the performance of these software packages in predicting ischemic core and tissue-at-risk in the real-world setting. The aim of this study was to evaluate whether ischemic core on non-contrast CT (NCCT) and automated CTP correspond and predict infarct extent after thrombectomy for ischemic stroke.
Methods
Consecutive patients with acute anterior circulation large vessel occlusion undergoing successful thrombectomy (TICI 2b/3) were studied. All patients had baseline CT, CTP with RAPID post-processing software (RAPID-CTP), and post-thrombectomy 24 h CT. Ischemic cores were assessed by two blinded raters independently using the Alberta Stroke Program Early Computed Tomography Score (ASPECTS) on each modality. The interrater agreement for ASPECTS, and correlation between baseline CT-ASPECTS, RAPID-CTP-ASPECTS, and 24h CT-ASPECTS were calculated.
Results
A total of 86 patients with a mean age of 70.3 years (SD 16.5) were studied. The median baseline CT-ASPECTS was 9.5 (interquartile range, IQR 8–10), median RAPID-CTP-ASPECTS was 9 (IQR 8–10), and mean RAPID-CTP-ischemic core volume was 14.4 ml (SD 27.9 ml). The mean mismatch volume (difference of Tmax > 6s and cerebral blood flow (CBF) < 30%) was 128.6 ml (SD 126.0 ml). There was substantial correlation between baseline and 24h CT-ASPECTS (r
s
: 0.62;
p
< 0.001), but poor correlation between RAPID-CTP-ASPECTS and RAPID-CTP ischemic core volume with 24h NCCT-ASPECTS (r
s
: 0.21;
p
= 0.06 and −0.16;
p
= 0.15 respectively). The positive predictive value of any established infarct for baseline CT-ASPECTS was 81%, while that of RAPID-CTP-ASPECTS was 64%.
Conclusion
In this series of successfully revascularized patients, ischemic core as estimated by RAPID-CTP-ASPECTS did not correlate with the baseline CT and tended to depict a larger infarct core than the infarct extent as assessed by 24h CT-ASPECTS.
Journal Article