scholarly journals Reduced Blood Flow in Normal White Matter Predicts Development of Leukoaraiosis

2015 ◽  
Vol 35 (10) ◽  
pp. 1610-1615 ◽  
Author(s):  
Manya Bernbaum ◽  
Bijoy K Menon ◽  
Gordon Fick ◽  
Eric E Smith ◽  
Mayank Goyal ◽  
...  

The purpose of this study was to investigate whether low cerebral blood flow (CBF) is associated with subsequent development of white matter hyperintensities (WMH). Patients were included from a longitudinal magnetic resonance (MR) imaging study of minor stroke/transient ischemic attack patients. Images were co-registered and new WMH at 18 months were identified by comparing follow-up imaging with baseline fluid-attenuated inversion recovery (FLAIR). Regions-of-interest (ROIs) were placed on FLAIR images in one of three categories: (1) WMH seen at both baseline and follow-up imaging, (2) new WMH seen only on follow-up imaging, and (3) regions of normal-appearing white matter at both time points. Registered CBF maps at baseline were used to measure CBF in the ROIs. A multivariable model was developed using mixed-effects logistic regression to determine the effect of baseline CBF on the development on new WMH. Forty patients were included. Mean age was 61 ± 11 years, 30% were female. Low baseline CBF, female sex, and presence of diabetes were independently associated with the presence of new WMH on follow-up imaging. The odds of having new WMH on follow-up imaging reduces by 0.61 (95% confidence interval = 0.57 to 0.65) for each 1 mL/100 g per minute increase in baseline CBF. We conclude that regions of white matter with low CBF develop new WMH on follow-up imaging.

2016 ◽  
Vol 36 (9) ◽  
pp. 1528-1536 ◽  
Author(s):  
Nutta-on Promjunyakul ◽  
David L Lahna ◽  
Jeffrey A Kaye ◽  
Hiroko H Dodge ◽  
Deniz Erten-Lyons ◽  
...  

Normal-appearing white matter (NAWM) surrounding WMHs is associated with decreased structural integrity and perfusion, increased risk of WMH growth, and is referred to as the WMH penumbra. Studies comparing structural and cerebral blood flow (CBF) penumbras within the same individuals are lacking, however, and would facilitate our understanding of mechanisms resulting in WM damage. This study aimed to compare both CBF and structural WMH penumbras in non-demented aging. Eighty-two elderly volunteers underwent 3T-MRI including fluid attenuated inversion recovery (FLAIR), pulsed arterial spin labeling and diffusion tensor imaging (DTI). A NAWM layer mask was generated for periventricular and deep WMHs. Mean CBF, DTI-fractional anisotropy (DTI-FA), DTI-mean diffusivity (DTI-MD) and FLAIR intensity for WMHs and its corresponding NAWM layer masks were computed and compared against its mean within total brain NAWM using mixed effects models. For both periventricular and deep WMHs, DTI-FA, DTI-MD and FLAIR intensity changes extended 2-9 mm surrounding WMHs (p ≤ 0.05), while CBF changes extended 13-14 mm (p ≤ 0.05). The CBF penumbra is more extensive than structural penumbras in relation to WMHs and includes WM tissue both with and without microstructural changes. Findings implicate CBF as a potential target for the prevention of both micro and macro structural WM damage.


2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Jing Lin ◽  
Dilong Wang ◽  
Linfang Lan ◽  
Yuhua Fan

White matter lesions (WMLs), also known as leukoaraiosis (LA) or white matter hyperintensities (WMHs), are characterized mainly by hyperintensities on T2-weighted or fluid-attenuated inversion recovery (FLAIR) images. With the aging of the population and the development of imaging technology, the morbidity and diagnostic rates of WMLs are increasing annually. WMLs are not a benign process. They clinically manifest as cognitive decline and the subsequent development of dementia. Although WMLs are important, their pathogenesis is still unclear. This review elaborates on the advances in the understanding of the pathogenesis of WMLs, focusing on anatomy, cerebral blood flow autoregulation, venous collagenosis, blood brain barrier disruption, and genetic factors. In particular, the attribution of WMLs to chronic ischemia secondary to venous collagenosis and cerebral blood flow autoregulation disruption seems reasonable. With the development of gene technology, the effect of genetic factors on the pathogenesis of WMLs is gaining gradual attention.


2019 ◽  
Vol 40 (9) ◽  
pp. 1797-1805 ◽  
Author(s):  
Ying Zhou ◽  
Qingqing Li ◽  
Ruiting Zhang ◽  
Wenhua Zhang ◽  
Shenqiang Yan ◽  
...  

Our purpose is to assess the role of deep medullary veins in pathogenesis of lacunes in patients with cerebral small vessel disease (cSVD). We included patients with baseline and 2.5-year follow-up MRI in CIRCLE study. Susceptibility Weighted Imaging-Phase images were used to evaluate deep medullary veins based on a brain region-based visual score, and T2-Fluid-Attenuated-Inversion-Recovery images were used to evaluate lacunes. Cerebral blood flow and microstructural parameters in white matter hyperintensities and normal appearing white matter were also analyzed. A total of 203 cSVD patients were analyzed and 101 (49.8%) patients had baseline lacunes. Among them, 64 patients had follow-up MRI, including 16 (25.0%) with new lacunes. The patients’ deep medullary veins median score was 9 (7–12). At baseline, high deep medullary veins score was independently associated with the presence of lacunes after adjusting for age, diabetes mellitus, white matter hyperintensities volume and cerebral blood flow or white matter microstructural parameters (all p <  0.001). Longitudinally, high deep medullary veins score was independently associated with new lacunes after adjusting for gender ( p <  0.001). The association was also independent of white matter hyperintensities volumes, cerebral blood flow or white matter microstructural parameters (all p <  0.05). Our results suggest that deep medullary veins disruption might be involved in pathogenesis of lacunes.


Stroke ◽  
2020 ◽  
Vol 51 (Suppl_1) ◽  
Author(s):  
Shinichiro Uchiyama ◽  
Takao Hoshino ◽  
Hugo Charles ◽  
Kenji Kamiyama ◽  
Taizen Nakase ◽  
...  

Background: We have reported 5-year risk of stroke and vascular events after a transient ischemic attack (TIA) or minor ischemic stroke in patients enrolled into the TIAregistry.org, which was an international multicenter-cooperative, prospective registry (N Engl J Med 2018;378:2182-90). We conducted subanalysis on the 5-year follow-up data of Japanese patients in comparison with non-Japanese patients. Methods: The patients were classified into two groups on ethnicity, Japanese (n=345) and non-Japanese (n=3502), and their 5-year event rates were compared. We also determined predictors of five-year stroke in both groups. Results: Death from vascular cause (0.9% vs 2.7%, HR 0.28, 95% CI 0.09-0.89, p=0.031) and death from any cause (7.8% vs 9.9%, HR 0.67, 95% CI 0.45-0.99, p=0.045) were fewer in Japanese patients than in non-Japanese patients, while stroke (13.9% vs 7.2%, HR 1.78, 95% CI 1.31-2.43, p<0.001) and intracranial hemorrhage (3.2% vs 0.8%, HR 3.61. 95% CI 1.78-7.30, p<0.001) were more common in Japanese than non-Japanese patients during five-year follow-up period. Caplan-Meyer curves at five-years showed that the rates of stroke was also significantly higher in Japanese than non-Japanese patients (log-rank test, p=0.001). Predictors for stroke recurrence at five years were large artery atherosclerosis (HR 1.81, 95% CI 1.31-2.52, p<0.001), cardioembolism (HR 1.71, 95% CI 1.18-2.47, p=0.004), multiple acute infarction (HR 1.77, 95% CI 1.27-2.45, p<0.001) and ABCD 2 score 6 or 7 (HR 1.96, 95% CI 1.38-2.78, p<0.001) in non-Japanese patients, although only large artery atherosclerosis (HR 3.28, 95% CI 1.13-9.54, p=0.029) was a predictor for stroke recurrence in Japanese patients. Conclusions: Recurrence of stroke and intracranial hemorrhage were more prevalent in Japanese than non-Japanese patients. Large artery atherosclerosis was a predictor for stroke recurrence not only in non-Japanese patients but also in Japanese patients.


2018 ◽  
Vol 5 (5) ◽  
pp. e480 ◽  
Author(s):  
Kianush Karimian-Jazi ◽  
Brigitte Wildemann ◽  
Ricarda Diem ◽  
Daniel Schwarz ◽  
Thomas Hielscher ◽  
...  

ObjectiveTo assess the diagnostic value of gadolinium (Gd) contrast administration in MRI follow-up examinations of patients with MS if the T2 lesion load is stable.MethodsWe included 100 patients with MS with at least 2 cranial MRI follow-up examinations (mean follow-up time 4.0 ± 2.6 years). MRI was performed at 3 Tesla with a standardized protocol including T2-weighted, fluid-attenuated inversion recovery (FLAIR) and T1-weighted contrast-enhanced sequences. Images were analyzed for T2/FLAIR and contrast-enhancing (CE) lesions by 3 independent neuroradiologists. Isolated Gd-enhancing lesions without correlate in T2 and FLAIR images, and reactivated Gd+ lesions were further assessed for size and signal intensity.ResultsWe identified a total of 343 new T2 lesions and 152 CE lesions in a total of 559 MRI follow-up examinations. New T2/FLAIR lesions were present in 30% of the scans. Of the Gd-enhancing lesions, 145/152 (95.4%) showed a correlate as a new T2/FLAIR lesion. There were 3 enhancing lesions (1.9% of all enhancing lesions) without T2/FLAIR correlate and 4 lesions (2.6%) that exhibited lesion reactivation or persistent enhancement over time. As a predictive factor of enhancement, we found that enhancing lesions had a higher T2 signal ratio (T2 SRlesion/normal-appearing white matter: 3.0 ± 0.1 vs 2.2 ± 0.1, p < 0.001).ConclusionThe likelihood of missing “active lesions” is overall small (1.7%) if T2 lesions are stable compared with the previous MRI examination. Lesion reactivation is rare. Our study indicates that Gd contrast administration might be dispensable in follow-up MRI of patients with MS if no new T2/FLAIR lesions and no new neurologic symptoms are present.


Stroke ◽  
2013 ◽  
Vol 44 (suppl_1) ◽  
Author(s):  
Leka Sivakumar ◽  
Thomas Jeerakathil ◽  
Negar Asdaghi ◽  
Richard Camicioli ◽  
Christian Beaulieu ◽  
...  

Background: Cognitive changes have been described in subacute TIA/minor stroke (TIA/MIS), but the temporal profile is unknown. We tested the hypothesis that TIA/MIS patients experience transient cognitive impairment, and that this can be predicted by Diffusion-Weighted Imaging (DWI) lesion volume. Methods: Acute TIA/MIS stroke (NIH stroke scale score ≤3) patients with no history of cognitive impairment were prospectively recruited within 72 h of onset. Patients underwent Montreal Cognitive Assessment (MoCA), Mini-Mental Status Examination (MMSE) and MRI, including DWI and Fluid-Attenuated Inverse Recovery (FLAIR) sequences, at baseline, days 7 and 30. DWI lesion and FLAIR chronic white matter hyperintensity (WMH) volumes were measured planimetrically. Results: Fifty patients (mean age 68 ±15.1 years) were imaged at a median (IQR) of 26.5 (28.5) h after onset. Cognitive impairment (scores ≤26) was detected more frequently with MoCA (31/50, 62%) than MMSE (13/50, 26%, p=0.009). Acute ischemic lesions (DWI) were present in 33 (66%) patients. Mean DWI volume at baseline was 4.5 ± 11.1ml. Patients with DWI lesions (22/33, 67%) had similar impairment rates as those without (9/17, 53%; p=0.34). Linear regression indicated no relationship between acute DWI lesion volume (log transformed) and baseline MoCA scores (β=0.028, 95% CI [-2.09, 2.44]). Impaired patients had larger WMH volumes (13.6 ± 21.9 ml) than unaffected patients (2.6 ± 3.2 ml, p=0.01). Log transformed WMH volumes were inversely predictive of baseline MoCA scores (β=-0.54, 95% CI [-7.84, -2.28]). Median MoCA scores improved over time (27(5) at day 7 and 28(5) at day 30). Patients with baseline impairment and an increase of ≥2 points on MoCA by day 30 were defined as reverters (N=20). DWI lesion frequency was similar in reverters and those with persisting impairment (75% vs 64%, p= 0.50), as was DWI (6.9 ±14.3 ml vs 1.2 ±1.9 ml; p= 0.113) and WMH lesion volume (17.0 ± 26.2 ml vs 8.1 ± 8.1 ml; p= 0.18). Conclusions: Most TIA/MIS patients have evidence of temporary acute cognitive impairment when assessed with MoCA. Deficits are correlated with chronic WMH, suggesting an unmasking of subclinical cognitive impairment. Temporary cognitive deficits should be considered in the management of TIA/MIS patients.


Stroke ◽  
2021 ◽  
Vol 52 (Suppl_1) ◽  
Author(s):  
Rachelle Dugue ◽  
Joshua Z Willey ◽  
Eliza C Miller ◽  
Ian M Kronish ◽  
Bernard P Chang

Introduction: Recent work has demonstrated the safety and feasibility of rapid outpatient evaluation for presentations of TIA and non-disabling stroke. Our outpatient TIA and stroke clinic, Rapid Access Vascular Evaluation-Neurology (RAVEN) clinic, instituted in 2016, encountered unprecedented challenges in operations during the COVID-19 surge in New York City, leading to the creation of a telemedicine approach to minimize patient and staff exposure risk. To date, few virtual TIA/stroke clinics have reported on safety and feasibility outcomes. Hypothesis: We hypothesized that rapid follow-up of patients with suspected TIA and minor stroke via telemedicine would be feasible and safe during the pandemic. Methods/Results: We performed a retrospective chart review of patients with TIA and minor stroke who were referred to the virtual clinic from the emergency department (ED) between March and June 2020 (the local peak of the COVID-19 pandemic) when RAVEN in-person visits were suspended. A total of 24 patients were discharged early from the ED and referred for RAVEN evaluation with 20 patients evaluated as scheduled; 4 were lost to RAVEN follow-up. Ultimately, 60% of these patients were diagnosed with TIA or minor stroke after completing their remote evaluation; the rest were diagnosed as stroke mimics (seizure, migraine with aura, neuropathy, peripheral vertigo, stroke recrudescence). The median NIHSS calculated at initial ED evaluation was 1 with a maximum NIHSS of 5. A new medical intervention for secondary prevention was prescribed for 70% of patients prior to ED discharge. Amongst patients contacted by phone 3-5 months post-RAVEN evaluation, 4 of 15 had an increased modified Rankin score. Of the 24 patients referred for RAVEN evaluation, 7 returned to the ED within 90 days, with 3 patients citing neurologic complaints. On follow-up via phone conducted 2-5 months after RAVEN evaluation, 3 of 17 patients self-reported either a positive COVID-19 test or suspected COVID-19 diagnosis over the study period. Conclusion: A telemedicine-based approach to evaluate TIA and stroke in the RAVEN model helped limit patient infection risk, optimize resource allocation, establish accurate, timely diagnoses, and effectively implement secondary prevention strategies.


2004 ◽  
Vol 10 (2) ◽  
pp. 188-196 ◽  
Author(s):  
Emmanuelle Cassol ◽  
Jean-Philippe Ranjeva ◽  
Danielle Ibarrola ◽  
Claude Mékies ◽  
Claude Manelfe ◽  
...  

Our objectives were to determine the reproducibility of diffusion tensor imaging (DTI) in volunteers and to evaluate the ability of the method to monitor longitudinal changes occurring in the normal-appearing white matter (NAWM) of patients with multiple sclerosis (MS). DTI was performed three-mo nthly for one year in seven MS patients: three relapsing-remitting (RRMS), three secondary progressive (SPMS) and one relapsing SP. They were selected with a limited cerebral lesion load. Seven age- and sex-matched controls also underwent monthly examinations for three months. Diffusivity and anisotropy were quantified over the segmented whole supratentorial white matter, with the indices of trace (Tr) and fractional anisotropy (FA). Results obtained in volunteers show the reproducibility of the method. Patients had higher trace and lower anisotropy than matched controls (P B-0.0001). O ver the follow-up, both Tr and FA indicated a recovery after the acute phase in RRMS and a progressive shift towards abnormal values in SPMS. A lthough this result is not statistically significant, it suggests that DTI is sensitive to microscopic changes occurring in tissue of normal appearance in conventional images and could be useful for monitoring the course of the disease, even though it was unable to clearly distinguish between the various physiopathological processes involved.


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