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Siva, Aksel

0000-0002-8340-6641

Mayo Clinic

Cerraphasa University, Istanbul, Turkiye.

Citations 33

Risk Factors and Time to Clinical Symptoms of Multiple Sclerosis Among Patients With Radiologically Isolated Syndrome
Rollot, Fabien , Mondot, Lydiane, Louapre, Céline , Page, Emmanuelle Le , Durand‐Dubief, Françoise , Labauge, Pierre, Bensa, Caroline , Thouvenot, Éric , Ciron, Jonathan , Bourre, Bertrand , Cabre, Philippe, Casez, Olivier , Ruet, Aurélie , Mathey, Guillaume , Berger, Éric , Moreau, Thibault, Khedr, A. Al, Derache, Nathalie, Guennoc, Anne‐Marie, Créange, Alain , Neau, Jean‐Philippe, Tourbah, Ayman , Camdessanché, Jean‐Philippe , Maarouf, Adil , Callier, Céline, Kantarci, Orhun H. , Sıva, Aksel , Azevedo, Christina , Makhani, Naila , Pelletier, Daniel , Investigators, RISC, SFSEP, and OFSEP, Pelletier, Daniel, Azevedo, Christina, Radji, Fataï, Morel, Nathalie, Grosset-Jeannin, Deborah, Ungureanu, Aurelian , Boyer, L, Suchet, Laurent , Elias, Zyad, Brochet, Bruno, Defer, Gilles , Branger, Pierre , Clavelou, Pierre, Taithe, Frédéric, Alkhedr, Adullatif, Fromont, Agnès, Hautecoeur, Patrick, Androdias, G. , Ionescu, Iuliana, Pelletier, Jean , Audoin, Bertrand , Labauge, Pierre, Debouverie, Marc, Laplaud, David, Wiertlevski, Sandrine, Bresch, Saskia , Castelnovo, Giovanni, Papeix, Caroline , Lubetzki, Catherine , Stankoff, Bruno, Fontaine, Bertrand , Giannesini, C. , Heinzleff, Olivier, Bourre, Bertrand, Gout, Olivier , Guegen, Antoine, Leray, Emmanuelle , Guennoc, Anne Marie , Broucker, T. de , Sehaki, Sabrina, Devys-Meyer, Nathalie, Bereau, Mathieu, Cappe, Chrystelle, Kounkou, Katy-Kim, Dumont, Émilie , Lescieux, Edwige, Protin, Alexia, Kane, Maty Diop, Boucher, Julie, Petit, Julie, Kasonde, Irène Tabellah, Vilmarrest, Aymeric de, Nicol, Marie , Malbezin, Muriel, Olaiz, Javier, Rigaud-Bully, Claire, Vukusic, Irena, Debard, Nadine, Cotton, François, Abdelalli, Amalle, Lelio, Bernadette Di, Pinna, Frédéric , Guillemin, Francis, Ziegler, Amandine, Zehrouni, Karima, Hodel, Jérôme , Wahab, Abir , Zedet, Mickaël, Fagniez, Ombeline, Laage, Clémence, Pottier, Corinne , Slesari, Iuliana, Sampaio, Mathilde, Rabois, Emilie, Castex, Cédric , Hébant, Benjamin , Guillaume, Maxime , Vimont, Christine, Muraz, Romain, Port, Damien Le, Henry, Carole , Berthe, Carole, Freitas, Noellie, Visneux, Vincent, Forestier, M., Beltran, S. , Meunier, Géraldine, Servan, Jérôme, Pico, Fernando, Chatagner, Virginie, Siva, Aksel , Thouvenot, Eric , Ciron, Jonathan , Durand-Dubief, Françoise , Lebrun‐Frénay, Christine , Mondot, Lydiane , Zéphir, Hélène , Laplaud, David , Seze, Jerome De , Bourre, Bertrand , Casez, Olivier , Clavelou, Pierre , Vermersch, Patrick , Cohen, Mikaël , Okuda, Darin T. , Vukusic, Sandra , Investigators, RISC, SFSEP, and OFSEP, Azevedo, Christina, Morel, Nathalie, Boyer, Latine, Ouallet, Jean‐Christophe , Clavelou, Pierre, Outteryck, Olivier , Hautecoeur, Patrick, Ayrignac, Xavier , Carra‐Dallière, Clarisse , Labauge, Pierre, Laplaud, David, Maillart, Elisabeth , Bourre, Bertrand, Michel, Laure , Magy, Laurent , Collongues, Nicolas , Biotti, Damien , Béreau, Matthieu , Casey, Romain , Muraz, Romain, Forestier, Melanie

JAMA Network Open | October 17, 2021 | Volume: 4 | Issue: 10 | Pages: e2128271

10.1001/jamanetworkopen.2021.28271 Get It

Long‐Term Safety and Efficacy of Eculizumab in Aquaporin‐4 IgG‐Positive NMOSD
Wingerchuk, Dean M. , Palace, Jacqueline , Levy, Michael , Kim, Jung Bin , Nakashima, Ichiro , Wang, Kai‐Chen , Miller, Larisa , Shang, Shulian, Sabatella, Guido, Yountz, Marcus, Pittock, Sean J. , Group, PREVENT Study, Sıva, Aksel , Tütüncü, Melih , Palace, Jacqueline , Pozzilli, Carlo , Clardy, Stacey , Hardy, Todd A. , Messina, Silvia , Totolyan, N. А. , Huda, Saif , Barnett, Michael , Sahagian, Gregory , Levy, Michael , Pittock, S J , Clardy, Stacey L , Nakashima, Ichiro , Siva, Aksel , Hardy, Todd A , Messina, Silvia , Palace, Jacqueline , Fujihara, Kazuo , Berthele, Achim , Oreja‐Guevara, Celia , Group, PREVENT Study, Barnett, Michael H , Pozzilli, Carlo

Annals of Neurology | February 17, 2021 | Volume: 89 | Issue: 6 | Pages: 1088-1098

10.1002/ana.26049 Get It

ObjectiveDuring PREVENT (NCT01892345), eculizumab significantly reduced relapse risk versus placebo in patients with aquaporin‐4 immunoglobulin G‐positive neuromyelitis optica spectrum disorder (AQP4‐IgG+ NMOSD). We report an interim analysis of PREVENT's ongoing open‐label extension (OLE; NCT02003144) evaluating eculizumab's long‐term safety and efficacy.MethodsPatients who completed PREVENT could enroll in the OLE to receive eculizumab (maintenance dose = 1,200 mg/2 weeks, after a blinded induction phase). Safety and efficacy data from PREVENT and its OLE (interim data cut, July 31, 2019) were combined for this analysis.ResultsAcross PREVENT and the OLE, 137 patients received eculizumab and were monitored for a median (range) of 133.3 weeks (5.1–276.9 weeks), for a combined total of 362.3 patient‐years (PY). Treatment‐related adverse event (AE) and serious adverse event (SAE) rates were 183.5 in 100 PY and 8.6 in 100 PY, respectively. Serious infection rates were 10.2 in 100 PY in eculizumab‐treated patients versus 15.1 in 100 PY in the PREVENT placebo group. No patient developed a meningococcal infection. At 192 weeks (3.7 years), 94.4% (95% confidence interval [CI], 88.6–97.3) of patients remained adjudicated relapse‐free. The adjudicated annualized relapse rate was 0.025 (95% CI = 0.013–0.048) in all eculizumab‐treated patients versus 0.350 (95% CI = 0.199–0.616) in the PREVENT placebo group. During the OLE, 37% of patients (44 of 119 patients) stopped or decreased background immunosuppressive therapy use.InterpretationThis analysis demonstrates that eculizumab's long‐term safety profile in NMOSD is consistent with its established profile across other indications. This analysis also demonstrated the sustained ability of long‐term eculizumab treatment to reduce relapse risk in patients with AQP4‐IgG+ NMOSD. ANN NEUROL 2021;89:1088–1098
Radiologically Isolated Syndrome: 10‐Year Risk Estimate of a Clinical Event
Lebrun‐Frénay, Christine , Kantarci, Orhun H. , Sıva, Aksel , Sormani, Maria Pia , Pelletier, Daniel, Okuda, Darin T. , OFSEP, for the 10‐year RISC study group on behalf of SFSEP,, Montalbán, Xavier , Uygunoğlu, Uğur , Zeydan, Burcu , Thouvenot, Éric , Laplaud, David , Ciron, Jonathan , Cohen, Mikaël , Kantarci, OH , Sormani, Maria P , Lebrun‐Frénay, Christine , Siva, Aksel , Zeydan, Burcu , Thouvenot, Eric , Ciron, Jonathan , Okuda, Darin T , OFSEP, for the 10‐year RISC study group on behalf of SFSEP,, Cohen, Mikaël

Annals of Neurology | June 5, 2020 | Volume: 88 | Issue: 2 | Pages: 407-417

10.1002/ana.25799 Get It

Objective We have previously identified male sex, younger age, and the presence of spinal cord lesions as independent factors that increase the 5‐year risk for evolution from radiologically isolated syndrome (RIS) to multiple sclerosis. Here, we investigate risk factors for the development of a clinical event using a 10‐year, multinational, retrospectively identified RIS dataset. Methods RIS subjects were identified according to 2009 RIS criteria and followed longitudinally as part of a worldwide cohort study. We analyzed data from 21 individual databases from 5 different countries. Associations between clinical and magnetic resonance imaging (MRI) characteristics and the risk of developing a first clinical event were determined using multivariate Cox regression models. Results Additional follow‐up data were available in 277 of 451 RIS subjects (86% female). The mean age at RIS diagnosis was 37.2 years (range, 11–74 years), with a median clinical follow‐up of 6.7 years. The cumulative probability of a first clinical event at 10 years was 51.2%. Age, positive cerebrospinal fluid for oligoclonal bands, infratentorial lesions on MRI, and spinal cord lesions, were baseline independent predictors associated with a subsequent clinical event. The presence of gadolinium‐enhanced lesions during follow‐up was also associated with the risk of a seminal event. The reason for MRI and gadolinium‐enhancing lesions at baseline did not influence the risk of a subsequent clinical event. Interpretation Approximately half of all individuals with RIS experience a first clinical event within 10 years of the index MRI. The identification of independent predictors of risk for symptom onset may guide education and clinical management of individuals with RIS. ANN NEUROL 2020;88:407–417.
Cerebellar volume loss in radiologically isolated syndrome
George, Ilena , Mendili, Mohamed Mounir El , Inglese, Matilde , Azevedo, Christina , Kantarci, Orhun H. , Sıva, Aksel , Okuda, Darin T. , Pelletier, Daniel , Siva, Aksel , Okuda, Darin T , Lebrun‐Frénay, Christine

Multiple Sclerosis Journal | November 4, 2019 | Volume: 27 | Issue: 1 | Pages: 130-133

10.1177/1352458519887346 Get It

Radiologically isolated syndrome (RIS), in which asymptomatic demyelinating-appearing lesions are detected incidentally on MRI, can be a pre-clinical form of multiple sclerosis (MS). In this study, we measured cerebellar volumes on 3D T1-weighted 3T MR images in 21 individuals with RIS and 38 age- and sex-matched healthy controls (HC). Normalized cerebellar white matter volume and the anterior cerebellar gray matter volume were significantly decreased in RIS compared to HC ( p = 0.003 and p = 0.005, respectively). Our findings support reports of regional brain atrophy in RIS prior to the development of a seminal attack related to inflammatory demyelination.
Oligoclonal bands increase the specificity of MRI criteria to predict multiple sclerosis in children with radiologically isolated syndrome
Makhani, Naila , Sıva, Aksel , Narula, Sona , Wassmer, Evangeline , Brassat, David, Brenton, J. Nicholas , Cabre, Philippe, Carra‐Dallière, Clarisse , Dubief, Françoise Durand, Inglese, Matilde , Langille, Megan, Mathey, Guillaume , Pelletier, Jean , Reich, Daniel S. , Rojas, Juan Ignacio , Shabanova, Veronika , Shapiro, Eugene D. , Stone, Robert T, Tenembaum, Sílvia , Tintoré, Mar , Uygunoğlu, Uğur , Vargas, Wendy , Venkateswaren, Sunita, Kantarci, Orhun H. , Pelletier, Daniel , Durand‐Dubief, Françoise , Carra Dallière, Clarisse , Reich, Daniel S , Tintoré, Mar , Brenton, J Nicholas , Siva, Aksel , Lebrun‐Frénay, Christine , Seze, Jerome De , Neuteboom, Rinze Frederik , Pohl, Daniela , Stone, Robert Thompson, Vermersch, Patrick , Okuda, Darin T. , Wassmer, Evangeline , Durand-Dubief, Françoise

Multiple Sclerosis Journal - Experimental, Translational and Clinical | March 21, 2019 | Volume: 5 | Issue: 1 | Pages: No page available

10.1177/2055217319836664 Get It

Background Steps towards the development of diagnostic criteria are needed for children with the radiologically isolated syndrome to identify children at risk of clinical demyelination. Objectives To evaluate the 2005 and 2016 MAGNIMS magnetic resonance imaging criteria for dissemination in space for multiple sclerosis, both alone and with oligoclonal bands in cerebrospinal fluid added, as predictors of a first clinical event consistent with central nervous system demyelination in children with radiologically isolated syndrome. Methods We analysed an international historical cohort of 61 children with radiologically isolated syndrome (≤18 years), defined using the 2010 magnetic resonance imaging dissemination in space criteria (Ped-RIS) who were followed longitudinally (mean 4.2 ± 4.7 years). All index scans also met the 2017 magnetic resonance imaging dissemination in space criteria. Results Diagnostic indices (95% confidence intervals) for the 2005 dissemination in space criteria, with and without oligoclonal bands, were: sensitivity 66.7% (38.4–88.2%) versus 72.7% (49.8–89.3%); specificity 83.3% (58.6–96.4%) versus 53.9% (37.2–69.9%). For the 2016 MAGNIMS dissemination in space criteria diagnostic indices were: sensitivity 76.5% (50.1–93.2%) versus 100% (84.6–100%); specificity 72.7% (49.8–89.3%) versus 25.6% (13.0–42.1%). Conclusions Oligoclonal bands increased the specificity of magnetic resonance imaging criteria in children with Ped-RIS. Clinicians should consider testing cerebrospinal fluid to improve diagnostic certainty. There is rationale to include cerebrospinal fluid analysis for biomarkers including oligoclonal bands in planned prospective studies to develop optimal diagnostic criteria for radiologically isolated syndrome in children.
Age is a critical determinant in recovery from multiple sclerosis relapses
Conway, Brittani L., Zeydan, Burcu , Uygunoğlu, Uğur , Novotná, Martina, Sıva, Aksel , Pittock, Sean J. , Atkinson, Elizabeth J. , Rodriguez, Moses , Kantarci, Orhun H. , Pittock, S J , Rodriguez, Moses , Siva, Aksel , Zeydan, Burcu

Multiple Sclerosis Journal | October 10, 2018 | Volume: 25 | Issue: 13 | Pages: 1754-1763

10.1177/1352458518800815 Get It

Objective: To evaluate the impact of age on recovery from multiple sclerosis relapses. Background: Increasing disability in multiple sclerosis is a consequence of progressive disease and incomplete relapse recovery. Methods: The first and last-ever relapse data (357 relapses in 193 patients) from the Olmsted County population-based multiple sclerosis cohort were systematically reviewed for age, fulminance, location (optic nerve, brainstem/cerebellar, spinal cord), peak deficit, and maximum recovery. Three different relapse-outcome measures were studied both as paired analyses and as an overall group effect: change from peak deficit to maximum recovery in raw functional system score related to the relapse (ΔFSS), a previously published FSS-based relapse-impact model, and change from peak deficit to maximum recovery in Extended Disability Status Scale (ΔEDSS) score. Results: Older age was linearly associated with worse recovery in the ΔFSS outcome ( p = 0.002), ΔEDSS outcome ( p < 0.001), and the FSS-based relapse-impact model ( p < 0.001). A multivariate analysis of ΔFSS outcome linked poor recovery to older age ( p = 0.015), relapse location (transverse myelitis or brainstem/cerebellar syndrome; p < 0.001), and relapse fulminance ( p = 0.004). Conclusion: Multiple sclerosis-relapse recovery declines in a linear fashion with increased age, which should be considered when making treatment decisions.
Cerebrospinal fluid chitinase-3-like protein 1 level is not an independent predictive factor for the risk of clinical conversion in radiologically isolated syndrome
Thouvenot, Éric , Hinsinger, Geoffrey, Dematteï, Christophe , Uygunoğlu, Uğur , Castelnovo, Giovanni, Pittion‐Vouyovitch, S., Okuda, Darin T. , Kantarci, Orhun H. , Pelletier, Daniel , Lehmann, Sylvain , Marin, Philippe , Sıva, Aksel , Lebrun‐Frénay, Christine , Lebrun‐Frénay, Christine , Siva, Aksel , Thouvenot, Eric , Okuda, Darin T , Lehmann, Sylvain

Multiple Sclerosis Journal | March 22, 2018 | Volume: 25 | Issue: 5 | Pages: 669-677

10.1177/1352458518767043 Get It

Background: Younger age, male sex and presence of spinal cord lesion(s) increase the risk of conversion from radiologically isolated syndrome (RIS) to relapsing-remitting multiple sclerosis (RRMS). Elevated cerebrospinal fluid (CSF) chitinase-3-like protein 1 (CHI3L1) levels predict conversion from clinically isolated syndrome (CIS) to RRMS. Objective: To evaluate the prognostic value of CSF CHI3L1 in RIS patients for conversion to RRMS. Methods: We compared CSF CHI3L1 concentrations in RIS, CIS, RRMS and symptomatic controls (SCs). We analysed the influence of epidemiological, radiological and CSF parameters on the risk of clinical event. Results: A total of 211 patients (71 RIS, 48 CIS, 50 RRMS and 42 SC) were included. CSF CHI3L1 levels were lower in RIS than in RRMS and higher in RIS with positive CSF versus negative CSF and SC. The presence of at least one spinal cord lesion was the only independent predictor of faster conversion to RRMS. Association of high CSF CHI3L1 levels, positive CSF (presence of oligoclonal bands and/or an elevated IgG index) or four Barkhof criteria with any spinal cord lesion showed a tendency for reduced mean conversion time. Conclusion: CSF CHI3L1 correlates with positive CSF but is not an independent predictor of the risk of conversion from RIS to RRMS.
Myelopathy in Behçet's disease: The Bagel Sign
Zeydan, Burcu , Özgüler, Yeşim , Uğurlu, Serdal , Koçer, Naci , Kantarci, Kejal , Saip, Sabahattin , Sıva, Aksel , Kantarci, Orhun H. , Uygunoğlu, Uğur , Seyahi, Emire , Işlak, Civan , Kantarci, Kejal , Siva, Aksel , Zeydan, Burcu

Annals of Neurology | July 27, 2017 | Volume: 82 | Issue: 2 | Pages: 288-298

10.1002/ana.25004 Get It

ObjectiveTo describe the clinical and distinctive imaging features of myelopathy associated with Behçet's disease (BD).MethodsWe evaluated the records of patients meeting the following criteria: (1) fulfillment of the International Study Group criteria for BD; (2) clinically suggestive of myelopathy; (3) simultaneous spinal cord and brain magnetic resonance images (MRIs) within 1 month of acute worsening of myelopathy; and (4) follow‐up duration ≥ 1 year after initial MRI evaluation. Patients not fulfilling all inclusion criteria and having MRIs with poor quality or missing sequences were excluded.ResultsIn 11 patients (9 men, 2 women), we studied 14 MRIs during distinct myelopathy episodes and nine follow‐up MRIs. Two distinct MRI patterns of spinal cord involvement were described according to T2‐weighted (T2W) axial images: (1) “Bagel Sign” pattern: a central lesion with hypointense core and hyperintense rim with or without contrast enhancement; and (2) “Motor Neuron” pattern: a symmetric involvement of the anterior horn cells. Bagel Sign was present in 13 of 14 myelopathy episodes whereas Motor Neuron pattern was observed in 1 of 14 MRIs. Of the 13 MRIs with Bagel Sign long myelopathy (n = 9), both long and short myelopathy (n = 2) and short myelopathy (n = 2) was observed. All patterns cleared with some residual lesions after steroid use and immunomodulation with associated clinical recovery in patients.InterpretationThe signal characteristics of the Bagel Sign potentially represent venous engorgement and/or acute blood products within the spinal cord. To our knowledge, Bagel Sign has not been observed in other forms of longitudinal myelopathy outside of BD, including neuromyelitis optica. Ann Neurol 2017;82:288–298
Infliximab is a plausible alternative for neurologic complications of Behçet disease
Zeydan, Burcu , Saip, Sabahattin , Demirci, Onat , Hamuryudan, Vedat , Sıva, Aksel , Kantarci, Orhun H. , Uygunoğlu, Uğur , Demirci, Onat N, Seyahi, Emire, Uğurlu, Serdal , Seyahi, Emire , Siva, Aksel , Zeydan, Burcu

Neurology Neuroimmunology & Neuroinflammation | July 12, 2016 | Volume: 3 | Issue: 5 | Pages: No page available

10.1212/nxi.0000000000000258 Get It