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Kantarci, Orhun H.

https://orcid.org/0000-0001-7038-8133

Mayo Clinic

Mayo Clinic

Citations 143

Upper cervical spinal cord atrophy in MS: Sex, menopause, and neurodegeneration
Zeydan, Burcu , Son, Jiye , Neyal, Nur , Schwarz, Christopher G. , Atkinson, Elizabeth J. , Nathoo, Nabeela , Kantarci, Kejal , Port, John D. , Kantarci, Orhun H. , Morrison, Holly A, Nathoo, Nabeela , Flanagan, E P , Port, John D , Schwarz, Christopher G , Kantarci, Kejal , Zeydan, Burcu , Morrison, Holly A, Flanagan, Eoin P.

Multiple Sclerosis Journal | January 18, 2025 | Volume: 31 | Issue: 3 | Pages: 278-289

10.1177/13524585241311441 Get It

Background: Spinal cord (SC) atrophy is a key imaging biomarker of progressive multiple sclerosis (MS). Progressive MS is more common in men and postmenopausal women. Objective: Investigate the impact of sex and menopause on SC measurements in persons with MS (pwMS). Methods: In pwMS and age- and sex-matched controls, upper cervical SC area from brain MRI (UCC brain ) was obtained. Impact of sex and menopause on UCC brain (adjusted for total intracranial volume) and its association with progression and disability, including MS functional composite (MSFC), were investigated. Results: UCC brain was smaller in pwMS ( n = 118, 51.4 ± 5.3 mm 2 ) than controls ( n = 118, 54.2 ± 4.4 mm 2 , p < 0.001) and inversely correlated with older age in pwMS ( r = −0.24, p = 0.010) but not in controls ( r = −0.025, p = 0.786). In 173 pwMS (413 brain MRIs), UCC brain was smaller in men (49.5 ± 5.9 mm 2 ) than women (51.6 ± 5.5 mm 2 , p = 0.001), postmenopausal women (49.4 ± 5.6 mm 2 ) than premenopausal women (52.9 ± 4.1 mm 2 , p < 0.001), and progressive (47.5 ± 5.6 mm 2 ) than relapsing MS (52.1 ± 5.2 mm 2 , p < 0.001). UCC brain also correlated with disease duration ( r = −0.39, p < 0.001), 9-hole peg test ( r = −0.26, p = 0.005), and severe ambulatory disability (Expanded Disability Status Scale ⩾6) ( r = −0.27, p < 0.001). Conclusion: UCC brain , a biomarker of progressive MS, is inversely associated with age, disease duration, male sex, and menopause, highlighting the potential impact of sex and hormones on neurodegeneration in MS.
Analysis of healthcare utilization before the diagnosis of radiologically isolated syndrome
Lebrun‐Frénay, Christine , Kerbrat, Sandrine , Okuda, Darin T. , Landes-Château, Cassandre , Kantarci, Orhun H. , Pierret, Chloé , Drézen, Erwan , Nowak, Emmanuel, Sıva, Aksel , Azevedo, Christina , Cohen, Mikaël , Leray, Emmanuelle , Azevedo, Christina J , Lebrun‐Frénay, Christine , Siva, Aksel , Okuda, Darin T , Cohen, Mikaël

Multiple Sclerosis Journal | January 11, 2025 | Volume: 31 | Issue: 2 | Pages: 184-196

10.1177/13524585241291471 Get It

Background: Previous studies have shown that people with multiple sclerosis (MS) had frequent healthcare visits up to 10 years before being diagnosed but with no information from magnetic resonance imaging (MRI) scans of the connection with the radiologically isolated syndrome (RIS). Objective: To analyze healthcare use 3 years before the RIS diagnosis. Methods: We examined healthcare usage before the first scan in RIS cases from 2010 to 2019. RIS subjects were identified from the French National MS observatory and compared to the general population (matched 10:1) and MS patients (matched 4:1). Results: Among 482 RIS individuals, 223 (46.3%) were not linked to the healthcare resources database. The remaining RIS individuals (53.7%) had higher healthcare usage before their RIS diagnosis for issues related to neurology visits, headaches (odds ratio (OR): 3.34, confidence interval (CI): [2.00–5.57], p < 0.0001), and the use of anti-migraine drugs (OR: 2.61, CI: [1.37–4.99], p = 0.004) compared to MS. Conclusion: Only about half of RIS patients had MS-selected healthcare resources, which allowed for data linkage. Those who did seek care before their RIS diagnosis were most commonly known for other neurological comorbidities. These findings do not support the idea of a systemic prodrome before RIS diagnosis.
Increase in white matter hyperintensities in long‐COVID depends on age and hospitalization during acute SARS‐CoV‐2
Atık, Merve, Kendall‐Thomas, June, Przybelski, Scott A. , Kantarci, Orhun H. , Toledano, Michel , Fought, Angela J. , Lesnick, Timothy G. , Gundry, Katie, Lorente, Alfredo, Thotland, Jeromy, Li, Xiufeng , Manousakis, Georgios , Metzler, Abby, Byrne, Keenan, Juttukonda, Meher R. , Salat, David H. , Sherman, Janet C. , Pollak, Lauren, Nabi, Mehreen, Rehman, Sana , Karmonik, Christof , Gillani, Syed A , Flores, Vanesa, Davis, Rachel, Ashizawa, Tetsuo , Ratai, Eva, Kantarci, Kejal, Harrold, G. Kyle , Zeydan, Burcu , Senjem, Matthew L. , Schwarz, Christopher G. , Silva, Ana Isabel , Joers, James M. , Lorente, Alfredo, Deelchand, Dinesh K. , Park, Young Woo , Lenglet, Christophe , Eberly, Lynn E. , Mukerji, Shibani S. , Yaşar, Sevil , Öz, Gülin , Kantarci, Kejal

Alzheimer's & Dementia | January 9, 2025 | Volume: 20 | Issue: S2 | Pages: No page available

10.1002/alz.090998 Get It

AbstractBackgroundApproximately 10% of patients with acute SARS‐CoV‐2 infection present with persistent symptoms recognized as the long‐COVID. Neurological and cognitive symptoms are prevalent in long‐COVID, requiring a deeper understanding of the biological basis of this condition for potential therapeutic interventions. Cerebrovascular complications are observed during acute infection, underscoring the importance of understanding cerebrovascular outcomes. Our objective was to investigate white matter hyperintensities (WMH) as a potential indicator of microvascular disease associated with long‐COVID in the brainMethodParticipants with long‐COVID (n=71; hospitalized, n=9, non‐hospitalized, n=62 during the acute infection) and controls (n=50) who did not have a reported infection were recruited from the community at five US sites that participated in the COVID‐Brain‐Advanced‐Imaging‐Network (COVID‐BRAIN) project. To be included, participants with long‐COVID had to experience neurological or cognitive sequelae within 6 months after a confirmed infection and continued to show at least one neurological symptom. Clinical evaluation and MRI were performed an average of 20±10 months after the acute infection. WMH volumes were measured from the 3D T2‐weighted FLAIR MRIs using a semi‐automated approach for the WMH segmentation. A linear regression model predicting log transformed WMH volume was used to investigate the association of age, groups (hospitalized long‐COVID, non‐hospitalized long‐COVID, controls), and the interaction of these two predictors along with an adjustment for total intracranial volume. Additionally, predicted regression lines have been plotted on the untransformed WMH scale.ResultWe observed a greater age‐dependent increase in WMH volumes in the hospitalized patients with long‐COVID compared to the control group (group*age interaction, p=0.005). We did not observe this difference in slopes in the non‐hospitalized patients with long‐COVID compared to the controls. Figure shows the slopes of WMH volume as a percentage of the total intracranial volume by age in the three groups.ConclusionOur preliminary observation in this ongoing long‐Covid study suggests that hospitalization during acute COVID is associated with the age‐dependent increase in microvascular injury in the white matter. Older adults with acute infection that require hospitalization are more susceptible to cerebrovascular adverse outcomes than controls or those who do not require hospitalization. Impact of such microvascular changes on cognitive outcomes and persistence of post‐COVID symptoms is yet to be studied.
Increase in white matter hyperintensities in long‐COVID depends on age and hospitalization during acute SARS‐CoV‐2
Atık, Merve, Kendall‐Thomas, June, Przybelski, Scott A. , Kantarci, Orhun H. , Toledano, Michel , Fought, Angela J. , Lesnick, Timothy G. , Gundry, Katie, Lorente, Alfredo, Thotland, Jeromy, Li, Xiufeng , Manousakis, Georgios , Metzler, Abby, Byrne, Keenan, Juttukonda, Meher R. , Salat, David H. , Sherman, Janet C. , Pollak, Lauren, Nabi, Mehreen, Rehman, Sana , Karmonik, Christof , Gillani, Syed A , Flores, Vanesa, Davis, Rachel, Ashizawa, Tetsuo , Ratai, Eva, Kantarci, Kejal, Harrold, G. Kyle , Zeydan, Burcu , Senjem, Matthew L. , Schwarz, Christopher G. , Silva, Ana Isabel , Joers, James M. , Lorente, Alfredo, Deelchand, Dinesh K. , Park, Young Woo , Lenglet, Christophe , Eberly, Lynn E. , Mukerji, Shibani S. , Yaşar, Sevil , Öz, Gülin , Kantarci, Kejal

Alzheimer's & Dementia | January 9, 2025 | Volume: 20 | Issue: S9 | Pages: No page available

10.1002/alz.093932 Get It

AbstractBackgroundApproximately 10% of patients with acute SARS‐CoV‐2 infection present with persistent symptoms recognized as the long‐COVID. Neurological and cognitive symptoms are prevalent in long‐COVID, requiring a deeper understanding of the biological basis of this condition for potential therapeutic interventions. Cerebrovascular complications are observed during acute infection, underscoring the importance of understanding cerebrovascular outcomes. Our objective was to investigate white matter hyperintensities (WMH) as a potential indicator of microvascular disease associated with long‐COVID in the brainMethodParticipants with long‐COVID (n = 71; hospitalized,n = 9,non‐hospitalized,n = 62 during the acute infection) and controls(n = 50) who did not have a reported infection were recruited from the community at five US sites that participated in the COVID‐Brain‐Advanced‐Imaging‐Network (COVID‐BRAIN) project. To be included, participants with long‐COVID had to experience neurological or cognitive sequelae within 6 months after a confirmed infection and continued to show at least one neurological symptom. Clinical evaluation and MRI were performed an average of 20±10 months after the acute infection. WMH volumes were measured from the 3D T2‐weighted FLAIR MRIs using a semi‐automated approach for the WMH segmentation. A linear regression model predicting log transformed WMH volume was used to investigate the association of age, groups (hospitalized long‐COVID, non‐hospitalized long‐COVID, controls), and the interaction of these two predictors along with an adjustment for total intracranial volume. Additionally, predicted regression lines have been plotted on the untransformed WMH scale.ResultWe observed a greater age‐dependent increase in WMH volumes in the hospitalized patients with long‐COVID compared to the control group (group*age interaction, p = 0.005). We did not observe this difference in slopes in the non‐hospitalized patients with long‐COVID compared to the controls. Figure shows the slopes of WMH volume as a percentage of the total intracranial volume by age in the three groups.ConclusionOur preliminary observation in this ongoing long‐Covid study suggests that hospitalization during acute COVID is associated with the age‐dependent increase in microvascular injury in the white matter. Older adults with acute infection that require hospitalization are more susceptible to cerebrovascular adverse outcomes than controls or those who do not require hospitalization. Impact of such microvascular changes on cognitive outcomes and persistence of post‐COVID symptoms is yet to be studied.
Differential Diagnosis of Suspected Multiple Sclerosis in Pediatric and Late-Onset Populations
Hua, Le H. , Solomon, Andrew , Tenembaum, Sílvia , Rostásy, Kevin , Newsome, Scott D. , Marrie, Ruth Ann , Magyari, Melinda , Kantarci, Orhun H. , Cohen, Jeffrey A., Bove, Riley , Banwell, Brenda , Magyari, Melinda , Scalfari, Antonio , Rovira, Àlex , Hemmer, Bernhard , Hemingway, Cheryl , Harnegie, Mary Pat , Graves, Jennifer , Corboy, John R. , Waubant, Emmanuelle L.

JAMA Neurology | September 16, 2024 | Volume: 81 | Issue: 11 | Pages: 1210

10.1001/jamaneurol.2024.3062 Get It

Importance While the typical onset of multiple sclerosis (MS) occurs in early adulthood, 2% to 10% of cases initially present prior to age 18 years, and approximately 5% after age 50 years. Guidance on approaches to differential diagnosis in suspected MS specific to these 2 age groups is needed. Observations There are unique biological factors in children younger than 18 years and in adults older than age 50 years compared to typical adult-onset MS. These biological differences, particularly immunological and hormonal, may influence the clinical presentation of MS, resilience to neuronal injury, and differential diagnosis. While mimics of MS at the typical age at onset have been described, a comprehensive approach focused on the younger and older ends of the age spectrum has not been previously published. Conclusions and Relevance An international committee of MS experts in pediatric and adult MS was formed to provide consensus guidance on diagnostic approaches and key clinical and paraclinical red flags for non-MS diagnosis in children and older adults.
Visual assessments of 11C-Pittsburgh compound-B PET vs. 18F-flutemetamol PET across the age spectrum
Zeydan, Burcu , Przybelski, Scott A. , Lesnick, Timothy G. , Kantarci, Orhun H. , Min, Hoon‐Ki , Kemp, Bradley J. , Jack, Clifford R. , Kantarci, Kejal , Lowe, Val J. , Min, Hoon-Ki Paul , Jack, Clifford R , Kantarci, Kejal , Zeydan, Burcu , Johnson, Derek R. , Schwarz, Christopher G. , Senjem, Matthew L.

Nuclear Medicine Communications | September 13, 2024 | Volume: 45 | Issue: 12 | Pages: 1047-1054

10.1097/mnm.0000000000001902 Get It

Objective Visual assessments of amyloid-β PET, used for Alzheimer’s disease (AD) diagnosis and treatment evaluation, require a careful approach when different PET ligands are utilized. Because the gray matter (GM) and white matter (WM) ligand bindings vary with age, the objective was to investigate the agreement between visual reads of 11C- and 18F-PET scans. Methods Cognitively unimpaired (CU) younger adults (N = 30; 39.5 ± 6.0 years), CU older adults (N = 30; 68.6 ± 5.9 years), and adults with AD (N = 22; 67.0 ± 8.5 years) underwent brain MRI, 11C-Pittsburgh compound-B (PiB)-PET, and 18F-flutemetamol-PET. Amyloid-β deposition was assessed visually by two nuclear medicine specialists on 11C-PiB-PET and 18F-flutemetamol-PET, and quantitatively by PET centiloids. Results Seventy-two 11C-PiB-PET and 18F-flutemetamol-PET visual reads were concordant. However, 1 18F-flutemetamol-PET and 9 11C-PiB-PET were discordant with quantitative values. In four additional cases, while 11C-PiB-PET and 18F-flutemetamol-PET visual reads were concordant, they were discordant with quantitative values. Disagreements in CU younger adults were only with 11C-PiB-PET visual reads. The remaining disagreements were with CU older adults. Conclusion Age, GM/WM binding, amyloid-β load, and disease severity may affect visual assessments of PET ligands. Increase in WM binding with age causes a loss of contrast between GM and WM on 11C-PiB-PET, particularly in CU younger adults, leading to false positivity. In CU older adults, increased WM signal may bleed more into cortical regions, hiding subtle cortical uptake, especially with 18F-flutemetamol, whereas 11C-PiB can detect true regional positivity. Understanding these differences will improve patient care and treatment evaluation in clinic and clinical trials.
Atypical Bilateral Idiopathic Inflammatory Cavernous Sinus Syndrome Responsive to Cyclophosphamide
Nathoo, Nabeela , Chodnicki, Kevin D. , Krecke, Karl N. , Nguyen, Aivi T. , Toledano, Michel , Kantarci, Orhun H. , Nguyen, Aivi T , Nathoo, Nabeela , Gompel, Jamie J. Van

Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques | March 5, 2024 | Volume: 52 | Issue: 1 | Pages: 159-161

10.1017/cjn.2024.29 Get It

The diagnostic value of the central vein sign in radiologically isolated syndrome
Landes-Château, Cassandre , Levraut, Michaël , Okuda, Darin T. , Themelin, Albert, Cohen, Mikaël , Kantarci, Orhun H. , Sıva, Aksel , Pelletier, Daniel, Mondot, Lydiane , Lebrun‐Frénay, Christine , Lebrun‐Frénay, Christine , Siva, Aksel , Okuda, Darin T , Cohen, Mikaël , Mondot, Lydiane

Annals of Clinical and Translational Neurology | January 8, 2024 | Volume: 11 | Issue: 3 | Pages: 662-672

10.1002/acn3.51986 Get It

AbstractObjectiveThe radiologically isolated syndrome (RIS) represents the earliest detectable preclinical phase of multiple sclerosis (MS). Increasing evidence suggests that the central vein sign (CVS) enhances lesion specificity, allowing for greater MS diagnostic accuracy. This study evaluated the diagnostic performance of the CVS in RIS.MethodsPatients were prospectively recruited in a single tertiary center for MS care. Participants with RIS were included and compared to a control group of sex and age‐matched subjects. All participants underwent 3 Tesla magnetic resonance imaging, including postcontrast susceptibility‐based sequences, and the presence of CVS was analyzed. Sensitivity and specificity were assessed for different CVS lesion criteria, defined by proportions of lesions positive for CVS (CVS+) or by the absolute number of CVS+ lesions.Results180 participants (45 RIS, 45 MS, 90 non‐MS) were included, representing 5285 white matter lesions. Among them, 4608 were eligible for the CVS assessment (970 in RIS, 1378 in MS, and 2260 in non‐MS). According to independent ROC comparisons, the proportion of CVS+ lesions performed similarly in diagnosing RIS from non‐MS than MS from non‐MS (p = 0.837). When a 6‐lesion CVS+ threshold was applied, RIS lesions could be diagnosed with an accuracy of 87%. MS could be diagnosed with a sensitivity of 98% and a specificity of 83%. Adding OCBs or Kappa index to CVS biomarker increased the specificity to 100% for RIS diagnosis.InterpretationThis study shows evidence that CVS is an effective imaging biomarker in differentiating RIS from non‐MS, with similar performances to those in MS.