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Zarrintan, Armin

0000-0002-1217-648X

Mayo Clinic

Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA.

Citations 5

CT perfusion for lesion-symptom mapping in large vessel occlusion ischemic stroke
Garrard, James , Neuhaus, Ain , Carone, Davide , Zarrintan, Armin , Harston, George , Brinjikji, Waleed , Kallmes, David F. , Garrard, James William , Zarrintan, Armin , Brinjikji, Waleed , Joly, Olivier , Rabinstein, Alejandro A. , Huynh, Thien

Journal of NeuroInterventional Surgery | December 18, 2024 | Volume: 18 | Issue: 1 | Pages: 149-154

10.1136/jnis-2024-022501 Get It

Background Identifying eloquent regions associated with poor outcomes based on CT perfusion (CTP) may help inform personalized decisions on selection for endovascular therapy (EVT) in patients with large vessel occlusion (LVO) ischemic stroke. This study aimed to characterize the relationship between CTP-defined hypoperfusion and National Institutes of Health Stroke Scale (NIHSS) subitem deficits. Methods Patients with anterior circulation LVO, baseline CTP, itemized NIHSS at presentation and 24 hours were included. CTP was analyzed using e-CTP (Brainomix, UK). Time to maximal contrast (Tmax) prolongation was defined as >6 s, and penumbra as the difference between Tmax and ischemic core (relative cerebral blood flow<30%). Voxel-lesion-symptom mapping was performed using sparse canonical correlation analysis. For each NIHSS subitem, and total NIHSS, the associations were plotted between Tmax voxels with baseline NIHSS, and penumbra voxels with delta NIHSS (24 hours minus baseline). Results This study included 171 patients. Total NIHSS was predicted by hypoperfusion in left frontal cortex and subcortical white matter tracts. Voxels associated with neurological recovery were symmetrical and subcortical. Limb deficits were associated with respective motor cortex regions and descending motor tracts, with negative correlation within the contralateral hemispheres. A similar but smaller cluster of voxels within the penumbra was associated with NIHSS improvement. Language impairment correlated with left frontal cortex and superior temporal gyrus voxels. With the exception of dysarthria, significant associations were observed and more diffusely distributed in all other NIHSS subitems. Conclusions These results demonstrate the feasibility of hypoperfusion-to-symptom mapping in LVO. Symptom-based mapping from presenting imaging could refine treatment decisions targeting specific neurological deficits.
Bacterial signature in retrieved thrombi of patients with acute ischemic stroke—a systematic review
Zarrintan, Armin , Ghozy, Sherief , Thirupathi, K., Walden, Kalah, Brinjikji, Waleed , Kallmes, David F. , Kadirvel, Ramanathan , Thirupathi, Kasthuri, Ghozy, Sherief , Zarrintan, Armin , Thirupathi, Kasthuri

Therapeutic Advances in Neurological Disorders | November 9, 2024 | Volume: 17 | Issue: No issue available | Pages: No page available

10.1177/17562864241296713 Get It

Background: Acute ischemic stroke (AIS) imposes a major healthcare burden. It is hypothesized that bacterial infection could influence atherosclerosis and thrombus formation, potentially contributing to AIS. Objectives: We aim to systematically review all studies that have investigated the presence of bacterial signatures within thrombi retrieved following mechanical thrombectomy (MT) procedures in patients with AIS. Design: This systematic review is designed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 checklist. Data sources and methods: A comprehensive search was conducted in the Web of Sciences, PubMed, Scopus, and Embase databases to identify relevant studies. Results: The literature search and screening included 11 studies involving 674 patients, with 414 (61.4%) being male and 260 (38.6%) females. Among all the patients, 393 (58.3%) were positive for bacterial presence in their retrieved thrombi. The most utilized technique for bacterial signature detection was bacterial DNA extraction followed by polymerase chain reaction amplification of the 16S rRNA gene sequence. Staphylococcus aureus was the most studied bacteria among the studies analyzed. Conclusion: Bacterial infections and the presence of bacteria within thrombi may significantly contribute to AIS by initiating or exacerbating atherosclerosis or thrombosis. Understanding the mechanisms by which bacteria affect vascular health is crucial for developing effective preventive and therapeutic strategies for stroke patients.
Efficacy and safety of flow diverters in retreatment of recurrent intracranial aneurysms—A systematic review and meta-analysis
Zarrintan, Armin , Ghozy, Sherief , Maroufi, Seyed Farzad , Reda, Abdullah, Brinjikji, Waleed , Kadirvel, Ramanathan , Kallmes, David F. , Gajjar, Aryan , Ghozy, Sherief , Zarrintan, Armin

Interventional Neuroradiology | September 14, 2024 | Volume: 32 | Issue: 4 | Pages: 1729-1740

10.1177/15910199241282713 Get It

Background and purpose Treatment of recurrent intracranial aneurysms after their initial therapy has been a significant challenge in the field of neurointervention. Recently flow diverters stents are widely used for treating intracranial aneurysms. In this systematic review and meta-analysis, we assessed the safety and efficacy of flow diverter in treating recurrent or recanalized intracranial aneurysms. Methods This meta-analysis is reported following the PRISMA 2020 guidelines. We conducted a systematic review of literature in the PubMed, Embase, Web of Sciences, and Scopus databases. Pooled prevalence and the corresponding 95% are calculated from extracted data using a random-effect model. Results The systematic literature search included 21 studies involving 411 patients, with 135 (32.8%) being male and 276 (67.2%) being females with a total number of 447 aneurysms. The overall rate of adequate occlusion was 90.67% (95% CI: 84.23%–94.65%), and the rates were comparable between the surgery (93.48%), coiling (91.78%), and stenting (85.77%) groups. The overall pooled rate of complete occlusion was 81.80 (95% CI: 71.14%–89.13%). On doing a subgroup analysis, the complete occlusion rates were 89.68%, 84.39%, and 73.47% for the surgery, coiling, and stenting groups, respectively. The overall mortality rate and achieving modified Rankin scale score of 0-2 was 1.28% (95% CI: 0.45%–3.64%) and (95% CI: 89.92%–97.84%), respectively. No significant heterogeneity is noted in the included studies. Conclusion Flow diverter stents are an effective and safe method for retreating recurrent or residual intracranial aneurysms with a high rate of complete and adequate occlusion. The rate of mortality, intracerebral hemorrhage, and overall and procedural complications following using flow diverters for intracranial aneurysms is low.
Neck apposition is a key factor for aneurysm occlusion after Woven EndoBridge device embolization
Cortese, Jonathan , Juhász, J , Rodriguez‐Erazú, Fernanda , Ghozy, Sherief , Bayraktar, Esref Alperen , Zarrintan, Armin , Ueki, Yasuhito , Caroff, Jildaz , Kallmes, David F. , Kadirvel, Ramanathan , Zarrintan, Armin , Caroff, Jildaz , Spelle, Laurent , Kadirvel, Ram , Ghozy, Sherief , Cortese, Jonathan , Bayraktar, Esref Alperen , Mihalea, Cristian , Spelle, Laurent

Journal of NeuroInterventional Surgery | August 8, 2024 | Volume: 17 | Issue: 10 | Pages: 1083-1088

10.1136/jnis-2024-022155 Get It

Background Sealing of the aneurysm neck with a Woven EndoBridge (WEB) device is recommended for disrupting the blood flow inside the aneurysm. This study investigates the relationship between WEB neck apposition and aneurysm occlusion rates. Methods Aneurysms treated with a WEB from March 2017 to May 2022 at a single center were included. WEB neck apposition (poor/good) and WEB protrusion (yes/no) were evaluated on post-detachment high resolution cone beam CT images. Angiographic occlusion was assessed with the Bicêtre Occlusion Scale score (BOSS). Univariate and multivariable analysis tested the association between neck apposition and occlusion rates. Results The study included 159 aneurysms in 141 patients (mean age 55.8±11.2 years; 64.2% women). Good neck apposition and protrusion were noted in 123 (77.4%) and 30 (18.9%) cases, respectively. Inter-rater agreements were good for neck apposition (κ=0.75) and protrusion (κ=0.78). Complete and adequate occlusion was achieved in 104 (65%) and 130 (82%) cases, respectively (median follow-up 18 months). Good neck apposition was a strong independent predictor for both adequate (adjusted OR (aOR)=5.9, 95% CI 2.4 to 14.9; P<0.001) and complete occlusion (aOR=7.1, 95% CI 3.0 to 18.1; P<0.001). Protrusion was more frequent in the adequate occlusion group versus the aneurysm recurrence group without reaching statistical significance (P=0.06), but was associated with more thromboembolic complications (9/30 (30%) vs 12/129 (9%); P<0.01). WEB shape modification was significantly greater in poor apposition cases (P=0.03). Conclusions Achieving good neck apposition of the WEB strongly predicts aneurysm occlusion during follow-up. WEB protrusion should be minimized due to the increase in thromboembolic risk with limited impact on aneurysm occlusion.
Region‐specific interobserver agreement of the Alberta Stroke Program Early Computed Tomography Score: A meta‐analysis
Zarrintan, Armin , Hamouda, Noha , Jabal, Mohamed Sobhi , Beizavi, Zahra , Kallmes, David F. , Ibrahim, Mohamed K. , Jabal, Mohamed Sobhi , Zarrintan, Armin , Ghozy, Sherief

Journal of Neuroimaging | January 8, 2024 | Volume: 34 | Issue: 2 | Pages: 195-204

10.1111/jon.13184 Get It

AbstractBackground and PurposeThe Alberta Stroke Program Early CT Score (ASPECTS) is a widely used scoring system for evaluating ischemic stroke to determine therapeutic strategy. However, there is variation in the interobserver agreement of ASPECTS. This systematic review and meta‐analysis aimed to investigate the interobserver agreement of total and regional ASPECTS.MethodsA comprehensive search was conducted in the Web of Sciences, PubMed, and Scopus databases to identify relevant studies. Inclusion criteria were studies of noncontrast CT performed within 24 hours of ischemic stroke in the middle cerebral artery territory.ResultsA total of 20 studies, with 3482 patients, reporting interobserver agreement of total and regional ASPECTS were included in the meta‐analysis. The interobserver agreement for total ASPECTS in studies using Kappa coefficient (κ) analysis was substantial (κ = .67, 95% confidence interval [CI]: .57‐.78). In studies using intraclass correlation coefficient (ICC) analysis, agreement was excellent (ICC = .84, 95% CI: .77‐.90). Interobserver agreement was higher in studies in which the observer was unblinded to clinical scenario in both groups (κ = .74, 95% CI: .59‐.89, and ICC = .82, 95% CI: .79‐.85). Per‐region analysis showed that the caudate nucleus had the highest agreement (κ = .68, 95% CI: .60‐.76, and ICC = .84, 95% CI: .74‐.93), while M2 and internal capsule in Kappa studies (κ = .45, 95% CI: .34‐.55 and κ = .47, 95% CI: .28‐.66), and M4 and internal capsule in ICC studies (ICC = .54, 95% CI: .43‐.64 and ICC = .55, 95% CI: .18‐.91) had the lowest agreement.ConclusionThis meta‐analysis demonstrates substantial to excellent interobserver agreement for total ASPECTS, which supports using this method for stroke treatment. However, findings emphasize the need to consider interobserver agreement in specific regions of ASPECTS for treatment decisions.