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Keser, Zafer

0000-0001-6415-0874

Mayo Clinic

Mayo Clinic

Citations 43

Epidemiology of Spontaneous Cervical Artery Dissection: Population-Based Study
Griffin, Kim J. , Harmsen, William S. , Mandrekar, Jay , Brown, Robert D. , Keser, Zafer , Keser, Zafer , Brown, Robert D

Stroke | January 30, 2024 | Volume: 55 | Issue: 3 | Pages: 670-677

10.1161/strokeaha.123.043647 Get It

BACKGROUND: Cervical artery dissection (CeAD) represents up to 15% to 25% of ischemic strokes in people under the age of 50 years. Noninvasive vessel imaging is increasingly used in clinical practice, but the impact on the frequency of detection of CeAD is unknown. In 2006, the yearly incidence rate of CeAD was estimated at 2.6 per 100 000 person-years, but the current incidence is unknown. METHODS: In this population-based retrospective observational cohort study, we utilized the resources of the Rochester Epidemiology Project to ascertain all adult residents of Olmsted County, MN, diagnosed with internal carotid artery dissection and common carotid artery dissection or vertebral artery dissection from 2002 to 2020. Patients with only intracranial involvement or CeAD following major trauma were excluded. Age-adjusted sex-specific and age- and sex-adjusted incidence rates were estimated using the US White 2010 decennial census, with rates expressed per 100 000 person-years. We assessed longitudinal trends by dividing the data into 5-year time intervals, with the last being a 4-year interval. RESULTS: We identified 123 patients with a diagnosis of CeAD. There were 63 patients with internal carotid artery dissection, 54 with vertebral artery dissection, 2 with concurrent internal carotid artery dissection and vertebral artery dissection, and 4 with common carotid artery dissection. There were 63 (51.2%) female patients and 60 (48.8%) male patients. The average age at diagnosis was 50.2 years (SD, 15.1 [95% CI, 20.1–90.5] years). The incidence rate of spontaneous CeAD encompassing all locations was 4.69 per 100 000 person-years (2.43 for internal carotid artery dissection and 2.01 for vertebral artery dissection). The incidence rate increased from 2.30 per 100 000 person-years from 2002 to 2006 to 8.93 per 100 000 person-years from 2017 to 2020 ( P <0.0001). The incidence rate for female patients rose from 0.81 per 100 000 person-years from 2002 to 2006 to 10.17 per 100 000 person-years from 2017 to 2020. CONCLUSIONS: The incidence rate of spontaneous CeAD increased nearly 4-fold over a 19-year period from 2002 to 2020. The incidence rate in women rose over 12-fold. The increase in incidence rates likely reflects the increased use of noninvasive vascular imaging.
Coronavirus Disease 2019 Infection in Cervical Artery Dissections
Wahood, Waseem , Keser, Zafer , Flemming, Kelly D. , Lanzino, Giuseppe , Keser, Zafer

The Neurologist | December 4, 2023 | Volume: 29 | Issue: 2 | Pages: 71-75

10.1097/nrl.0000000000000545 Get It

Objective: Most cervical artery dissection (CeAD) cases are spontaneous or due to minor traumas, and preceding viral infections have been suggested to be a triggering event for CeAD in some. Herein, we analyze the prevalence of coronavirus disease 2019 (COVID-19) in hospitalized patients with CeAD using a national database. Methods: The National Inpatient Sample was queried from April 2020 to December 2020 for patients with a diagnosis of CeAD using International Classification of Diseases, 10th edition-Clinical Modification codes. Among these, patients with COVID-19 were identified. Multivariable logistic regression was conducted to assess the patient profile of those with COVID-19, in-patient mortality, and home discharge among patients with CeAD. Results: There were 360 (2.32%) hospitalizations involving COVID-19 among 15,500 with CeAD. Concomitant acute ischemic stroke constituted 43.06% of those with a COVID-19 diagnosis, whereas it was 43.73% among those without a COVID-19 diagnosis (P = 0.902). Home discharges were less common in patients with COVID-19 and CeAD compared to CeAD alone (34.85% vs. 48.63%; P = 0.03), but this was likely due to other factors as multivariate regression analysis did not show an association between COVID-19 and home discharges (odds ratio: 0.69; 95% CI: 0.39 to 1.25; P = 0.22). COVID-19 diagnosis had similar odds of inpatient mortality (odds ratio: 1.11; 95% CI: 0.43 to 2.84; P = 0.84). Conclusion: The prevalence of COVID-19 among hospitalized patients with CeAD is low with 2.32% of all CeAD cases. Concomitant COVID infection did not lead to an increased risk of stroke in CeAD. However, potentially worse functional outcomes (fewer home discharges) without an increase in mortality were seen in patients with COVID and CeAD.
Identifying the white matter pathways involved in multiple sclerosis-related tremor using diffusion tensor imaging
Bayoumi, Ahmed , Hasan, Khader M. , Patiño, Jorge , Thomas, Joseph, Gabr, Refaat E. , Pedroza, Claudia , Schiess, Mya C. , Wolinsky, Jerry S. , Lincoln, John A. , Gabr, Refaat E , Wolinsky, Jerry S , Lincoln, John A , Keser, Zafer , Keser, Zafer , Kamali, Arash

Multiple Sclerosis Journal - Experimental, Translational and Clinical | November 8, 2023 | Volume: 9 | Issue: 4 | Pages: No page available

10.1177/20552173231208271 Get It

Background Tremor affects up to 45% of patients with Multiple Sclerosis (PwMS). Current understanding is based on insights from other neurological disorders, thus, not fully addressing the distinctive aspects of MS pathology. Objective To characterize the brain white matter (WM) correlates of MS-related tremor using diffusion tensor imaging (DTI). Methods In a prospective case-control study, PwMS with tremor were assessed for tremor severity and underwent MRI scans including DTI. PwMS without tremor served as matched controls. After tract selection and segmentation, the resulting diffusivity measures were used to calculate group differences and correlations with tremor severity. Results This study included 72 PwMS. The tremor group (n = 36) exhibited significant changes in several pathways, notably in the right inferior longitudinal fasciculus (Cohen's d = 1.53, q < 0.001) and left corticospinal tract ( d = 1.32, q < 0.001), compared to controls (n = 36). Furthermore, specific tracts showed a significant correlation with tremor severity, notably in the left medial lemniscus (Spearman's coefficient [ rsp] = −0.56, p < 0.001), and forceps minor of corpus callosum ( rsp = -0.45, p < 0.01). Conclusion MS-related tremor is associated with widespread diffusivity changes in WM pathways and its severity correlates with commissural and sensory projection pathways, which suggests a role for proprioception or involvement of the dentato-rubro-olivary circuit.
Advances in Stroke Neurorehabilitation
Gunduz, Muhammed Enes , Bucak, Bilal, Keser, Zafer , Keser, Zafer

Journal of Clinical Medicine | October 25, 2023 | Volume: 12 | Issue: 21 | Pages: 6734

10.3390/jcm12216734 Get It

Stroke is one of the leading causes of disability worldwide despite recent advances in hyperacute interventions to lessen the initial impact of stroke. Stroke recovery therapies are crucial in reducing the long-term disability burden after stroke. Stroke recovery treatment options have rapidly expanded within the last decade, and we are in the dawn of an exciting era of multimodal therapeutic approaches to improve post-stroke recovery. In this narrative review, we highlighted various promising advances in treatment and technologies targeting stroke rehabilitation, including activity-based therapies, non-invasive and minimally invasive brain stimulation techniques, robotics-assisted therapies, brain–computer interfaces, pharmacological treatments, and cognitive therapies. These new therapies are targeted to enhance neural plasticity as well as provide an adequate dose of rehabilitation and improve adherence and participation. Novel activity-based therapies and telerehabilitation are promising tools to improve accessibility and provide adequate dosing. Multidisciplinary treatment models are crucial for post-stroke neurorehabilitation, and further adjuvant treatments with brain stimulation techniques and pharmacological agents should be considered to maximize the recovery. Among many challenges in the field, the heterogeneity of patients included in the study and the mixed methodologies and results across small-scale studies are the cardinal ones. Biomarker-driven individualized approaches will move the field forward, and so will large-scale clinical trials with a well-targeted patient population.
Risk Profile of Patients with Spontaneous Cervical Artery Dissection
Zotto, Elisabetta Del, Zini, Andrea , Gandolfo, Carlo , Silvestrelli, Giorgio , Baracchini, Claudio , Cerrato, Paolo, Marcheselli, Simona , Paciaroni, Maurizio , Spalloni, Alessandra, DeLodovici, Maria Luisa , Magoni, Mauro, Azzini, Cristiano , Calloni, Maria, Giorli, Elisa , Melis, Fabio , Terruso, Valeria, Piras, Valeria , Giossi, Alessia , Sanguigni, Sandro, Zanferrari, Carla , Mannino, Marina , Colombo, Irene , Dallocchio, Carlo, Nencini, Patrizia , Bignamini, Valeria, Pezzini, Alessandro , Calabrò, Rocco Salvatore , Pezzini, Alessandro , Keser, Zafer , Grassi, Mario , Zedde, Marialuisa , Bersano, Anna , Lodigiani, Corrado , Cappellari, Manuel , Sette, Massimo Del , Cavallini, Anna Maria , Lotti, Enrico Maria , Gentile, Mauro , Padroni, Marina , Braga, M. , Spina, Paolo La, Tassi, Rossana , Adami, Alessandro , Bella, Rita , Pascarella, Rosario , Keser, Zafer

Annals of Neurology | June 7, 2023 | Volume: 94 | Issue: 3 | Pages: 585-595

10.1002/ana.26717 Get It

ObjectiveEpidemiological data to characterize the individual risk profile of patients with spontaneous cervical artery dissection (sCeAD) are rather inconsistent.Methods and ResultsIn the setting of the Italian Project on Stroke in Young Adults Cervical Artery Dissection (IPSYS CeAD), we compared the characteristics of 1,468 patients with sCeAD (mean age = 47.3 ± 11.3 years, men = 56.7%) prospectively recruited at 39 Italian centers with those of 2 control groups, composed of (1) patients whose ischemic stroke was caused by mechanisms other than dissection (non‐CeAD IS) selected from the prospective IPSYS registry and Brescia Stroke Registry and (2) stroke‐free individuals selected from the staff members of participating hospitals, matched 1:1:1 by sex, age, and race. Compared to stroke‐free subjects, patients with sCeAD were more likely to be hypertensive (odds ratio [OR] = 1.65, 95% confidence interval [CI] = 1.37–1.98), to have personal history of migraine with aura (OR = 2.45, 95% CI = 1.74–3.34), without aura (OR = 2.67, 95% CI = 2.15–3.32), and family history of vascular disease in first‐degree relatives (OR = 1.69, 95% CI = 1.39–2.05), and less likely to be diabetic (OR = 0.65, 95% CI = 0.47–0.91), hypercholesterolemic (OR = 0.75, 95% CI = 0.62–0.91), and obese (OR = 0.41, 95% CI = 0.31–0.54). Migraine without aura was also associated with sCeAD (OR = 1.81, 95% CI = 1.47–2.22) in comparison with patients with non‐CeAD IS. In the subgroup of patients with migraine, patients with sCeAD had higher frequency of migraine attacks and were less likely to take anti‐migraine preventive medications, especially beta‐blockers, compared with the other groups.InterpretationThe risk of sCeAD is influenced by migraine, especially migraine without aura, more than by other factors, increases with increasing frequency of attacks, and seems to be reduced by migraine preventive medications, namely beta‐blockers. ANN NEUROL 2023;94:585–595
Corticocerebellar White Matter Integrity Is Related to Naming Outcome in Post-Stroke Aphasia
Keser, Zafer , Stockbridge, Melissa D. , Sebastian, Rajani , Stockbridge, Melissa D , Breining, Bonnie L , Hillis, Argye Elizabeth , Sebastian, Rajani , Keser, Zafer , Meier, Erin L.

Neurobiology of Language | April 12, 2023 | Volume: 4 | Issue: 3 | Pages: 404-419

10.1162/nol_a_00107 Get It

Abstract Studies have shown that the integrity of white matter tracts connecting different regions in the left cerebral hemisphere is important for aphasia recovery after stroke. However, the impact of the underlying structural connection between the cortex and the cerebellum in post-stroke aphasia is poorly understood. We studied the microstructural integrity of the cerebellum and the corticocerebellar connections and their role in picture naming. Fifty-six patients with left cerebral infarcts (sparing the cerebellum) underwent diffusion tensor imaging (DTI) and Boston Naming Test. We compared the fractional anisotropy (FA) and mean diffusivity (MD) values of the right and the left cerebellum (lobular gray and white matter structures) and cerebellocortical connections. Recursive feature elimination and Spearman correlation analyses were performed to evaluate the relationship between naming performance and the corticocerebellar connections. We found that the right, relative to left, cerebellar structures and their connections with the left cerebrum showed lower FA and higher MD values, both reflecting lower microstructural integrity. This trend was not observed in the healthy controls. Higher MD values of the right major cerebellar outflow tract were associated with poorer picture naming performance. Our study provides the first DTI data demonstrating the critical importance of ascending and descending corticocerebellar connections for naming outcomes after stroke.
Traumatic posterior cerebral artery dissection and dissecting aneurysms: A systematic review with an illustrative case report
Essibayi, Muhammed Amir , Kerezoudis, Panagiotis, Keser, Zafer , Essibayi, Muhammed Amir , Kerezoudis, Panagiotis , Keser, Zafer , Lanzino, Giuseppe

Interventional Neuroradiology | March 8, 2023 | Volume: 32 | Issue: 3 | Pages: 691-697

10.1177/15910199231162487 Get It

Background Traumatic posterior cerebral artery (tPCA) dissection and dissecting aneurysms are rare and constitute a challenging clinical entity. Objective We analyze existing literature on tPCA dissection and present our institutional experience. Methods We retrospectively queried our database for tPCA isolated dissection or dissecting aneurysms from 2008 until now and conducted a systematic literature review of published cases. We analyzed the clinical and radiographic characteristics and treatment outcomes of tPCA dissection. Results Including our case, a total of 11 cases with either isolated dissection ( n = 2) or dissecting aneurysms ( n = 9) were included. The median age was 27 years, and 45% were females. The median interval between trauma and tPCA dissection diagnosis was nine days. Mental status declined in four (36%) patients. Half of the patients demonstrated tentorial subdural hematoma on head CT. Ischemic stroke was detected in three (43%) patients. Four (36%) patients were conservatively managed, one (9.1%) patient was treated with surgical clipping of the proximal PCA, and six patients underwent endovascular treatments. The complication rate was 20%. Immediate total occlusion was demonstrated in five patients (100%), and the conservatively managed case showed immediate, spontaneous thrombosis of the aneurysm. Glasgow Coma Scale scores were 15 in eight (89%) and 14 in one (11%) patients at the last clinical follow-up with a median of six months. The mortality and retreatment rates were null. Conclusions tPCA dissection is diagnosed late and commonly affects the young population. The clinical outcome for this condition is typically favorable. Current endovascular techniques showed considerable efficacy and safety.
Extracranial Internal Carotid and Vertebral Dissecting Pseudoaneurysms: Clinical Features and Long‐Term Outcomes
Seven, Nathan A. , Keser, Zafer , Keser, Zafer , Casanegra, Ana I. , Lanzino, Giuseppe

Stroke: Vascular and Interventional Neurology | January 28, 2023 | Volume: 3 | Issue: 3 | Pages: No page available

10.1161/svin.122.000703 Get It

Background The formation of dissecting pseudoaneurysms (dPSAs) is a common sequela of cervical artery dissection, which has been suggested to increase thrombotic risk in previous studies. This study reported clinical features and long‐term outcomes of cervical internal carotid (cICA) and vertebral artery (cVA) dPSAs. Methods We performed a retrospective chart review over a 10‐year period (January 2012–December 2021). Baseline demographics and clinical characteristics, medical and endovascular treatments, and long‐term outcomes were reported for cICA and cVA dPSA groups separately. Nonparametric tests were used to compare group differences. Results In our cohort, 120 (12%) of 999 cervical artery dissection patients had dPSA, with 85% occurring in the cICA and 15% in the cVA. Most dPSAs occurred spontaneously or in association with minor trauma. Compared with cICA dPSA, patients with cVA dPSA were younger (median age [range]=34.5 [24–70] versus 52 [30–77]; P <0.01), had a smaller dPSA size (median size [range]=4.5 mm [2–17] versus 8 mm [1.2–32]; P <0.01), and were more likely to reduce in size at follow‐up (median size change [range]=−2.8 mm [−17;0] versus 0 [−24;10.8]). Antithrombotic therapy was predominately aspirin monotherapy. No patients with cVA dPSA experienced recurrent strokes and only 3% of patients with cICA dPSA developed new/recurrent stroke in the territory of dPSA while on an antithrombotic regimen requiring endovascular intervention, and none of the dPSAs ruptured. A total of 98% of the patients had an excellent outcome (modified Rankin scale 0–2 at final follow‐up). Conclusion Most cICA and cVA dPSAs have a benign prognosis with medical therapy alone. Further prospective randomized clinical trials are needed to provide high quality evidence on the necessity of additional endovascular therapy at diagnosis in addition to medical therapy alone.
High‐resolution MRI to noninvasively characterize drainage around the carotid artery into the cervical lymph nodes
Keser, Zafer , Smith, Garrett , Cagil, Emin, Tufan, Fatih , Albayram, Önder , Keser, Zafer , Albayram, Sait

Journal of Neuroimaging | October 3, 2022 | Volume: 33 | Issue: 1 | Pages: 102-108

10.1111/jon.13056 Get It

AbstractBackground and PurposePrevious studies have proposed multiple parallel channels for waste clearance from the brain, though many gaps remain in our understanding of these systems. In this study, we examined periarterial fluid drainage around intracranial and extracranial segments of the internal carotid arteries (ICAs) from the brain into the cervical lymph nodes using a noninvasive and clinical‐based method.MethodsEighty‐one subjects (45 females, aged 15‐80 years old) with nonlesioned epilepsy underwent high‐resolution 3‐dimensional T2‐weighted fluid‐attenuated inversion recovery (FLAIR) MRI. We utilized a noninvasive and clinical‐based method with a manual semiautomated approach to characterize the periarterial lymphatic system's maximum thickness and signal intensities along the ICAs using high‐resolution 3‐dimensional FLAIR imaging. We conducted group comparisons and correlation analyses to investigate sex‐ and age‐based trends. Results were corrected with Bonferroni's test for multiple comparisons, and we performed power analysis for sample size calculations.ResultsUsing high‐resolution FLAIR images, we show evidence that fluid drainage emerges around the ICA petrous segment and joins lymphatic flow from cranial nerves in the upper neck, with this flow ultimately draining into the cervical lymph nodes bilaterally. Lymphatic signal at the petrous segment level was significantly thinner in females compared to males bilaterally (w = 413, p = .0001 on the right, w = 356, p < .0001 on the left). Lymphatic drainage around the petrous segments of the ICAs bilaterally was thicker with age in males but not in females.ConclusionsWe describe the in vivo high‐resolution imaging characteristics of periarterial fluid drainage along the vessel walls of ICAs. This represents a potentially major channel for brain waste clearance. We also report interesting sex‐ and age‐based trends in these structures within our cohort.
Vitamin K antagonist versus novel oral anticoagulants for management of cervical artery dissection: Interactive systematic review and meta-analysis
Essibayi, Muhammed Amir , Keser, Zafer , Essibayi, Muhammed Amir , Lanzino, Giuseppe , Keser, Zafer

European Stroke Journal | July 6, 2022 | Volume: 7 | Issue: 4 | Pages: 349-357

10.1177/23969873221111051 Get It

Purpose: Cervical artery dissection (CAD) represents a unique clinical entity with a high risk of ischemic stroke. Vitamin K antagonists (VKA) showed good efficacy in CAD management but are cumbersome to use with potentially higher bleeding rates. Novel oral anticoagulants (NOAC) are easier to use and may have similar effects but lower hemorrhagic risk. In this systematic review, we compare the efficacy of NOAC to VKA as a potential alternative treatment. Methods: The literature was searched on Pubmed, PMC, and Embase via API through the Nested Knowledge AutoLit software in February 2022 for studies evaluating both NOAC and VKA. Baseline characteristics, clinical and radiographic outcomes, and hemorrhagic and ischemic complications were collected for single and double-arm studies and analyzed using random-effect subgroup meta-analysis. Findings: Overall, 11 studies were included with 699 patients treated with VKA and 53 treated with NOAC (from three studies; two were head-to-head comparative studies). There was no statistical difference in the baseline characteristics of VKA and NOAC patients. The rates of TIA/stroke in VKA and NOAC groups were 12.3% (95% CI; 0%, 28.6%) and 5.7% (95% CI; 0%, 12.2%), respectively. Major bleeding or intracranial bleeding were comparable between groups. Lesions treated with VKA showed angiographic recanalization with a rate of 51.4% (95% CI; 35.6%, 67.1%) and for those treated with NOAC was 58.4% (95% CI; 23.9%, 93.9%). The rates of good clinical outcomes were 79.9% (95% CI; 67.6%, 92.2%) in the VKA group and 91.4% (95% CI; 78.1%, 100%) in NOAC. No statistical difference was noted among any of the outcomes between the two treatment groups. Discussion and conclusion: We highlighted comparable efficacy and safety of NOAC to VKA for stroke prevention in CAD. Further head-to-head studies are warranted to validate these results.