Neuromyelitis optica shorter lesion can cause important pyramidal deficits Denis Bernardi Bichuetti a, ⁎ ,1 , Marcelo Delboni Lemos b,2 , Isac de Castro c,3 , Gustavo Balthazar da Silveira Carvalho b,4 , Renato Sartori de Carvalho b,5 , Nitamar Abdala b,6 , Enedina Maria Lobato de Oliveira a,7 a Department of Neurology and Neurosurgery, Universidade Federal de São Paulo, Brazil b Department of Radiology, Universidade Federal de São Paulo, Brazil c Disciplina de Neurologia, Universidade Federal de São Paulo, Brazil abstract article info Article history: Received 8 April 2015 Received in revised form 8 June 2015 Accepted 9 June 2015 Available online 11 June 2015 Keywords: Neuromyelitis optica Short lesion Magnetic resonance imaging Clinical correlation Prognosis Pyramidal deficit Objective: Evaluate the correlation between spinal cord lesion length and pyramidal function system score in a cohort of patients with NMO. Methodology: Retrospective retrieval of all exams performed in our center from January 2004 to December 2012 for patients with NMO. The exams were evaluated for lesion length, contrast enhancement and T1 hypointensity; these variables were correlated with the functional system score from the EDSS, performed no more than three months from the scan. Results: 41 patients were included. Although patients with lesion extension ≥ 2 vertebral segments did not pres- ent worse pyramidal scores in a direct comparison, the influence of lesion length was not so strong when patients were separated in 3 groups (≥ 2, ≥ 3 or ≥ 4 vertebral segments) and evaluated with a receiving operating charac- teristics (ROC) curves. Gadolinium enhancement also contributed to more severe pyramidal system scores, but T1 hypointensity did not. Conclusion: Although patients with spinal cord lesion extending ≥3 vertebral segments had more pyramidal disabil- ity, its difference was not so strong when compared to patients with ≥ 2 or ≥4 vertebral segments. This suggests that lesion extension might not be the most important factor in favoring a worse prognosis in spinal cord lesions in NMO. © 2015 Elsevier B.V. All rights reserved. 1. Introduction Neuromyelitis optica (NMO) is an autoimmune disease character- ized by recurrent optic neuritis and transverse myelitis [1], but can also present distinct symptoms within a syndromic spectrum, known as NMO spectrum disorders (NMOSD), which include recurrent optic neuritis and recurrent longitudinal myelitis and specific brain and brainstem lesion and syndromes, associated to the anti aquaporin 4 antibody (anti-AQP4-IgG) [2]. The hallmark of the spinal cord lesion in these patients is a longitudinally extensive transverse myelitis (LETM), defined by magnetic resonance imaging (MRI) as a lesion ex- tending for 3 or more vertebral segments [1]. A short transverse myelitis (STM), defined as a MRI spinal cord le- sion not extending within and beyond 3 vertebral segments, has recent- ly been shown to be the initial presentation in 14% patients from a large NMO cohort [3]. The incorporation of STM within the NMO-SD might broaden the range of patients who are candidates for AQP4-IgG testing and treatment with early and aggressive immunosuppression, since halting further relapses can prevent neurological disability [4,5]. The goal of this study was to evaluate the influence of spinal cord le- sion length on clinical disability, and especially to compare patients with LETM and STM. 2. Methodology We retrieved all available MRI studies performed at the Department of Radiology, Universidade Federal de São Paulo, from patients followed Journal of the Neurological Sciences 355 (2015) 189–192 ⁎ Corresponding author. E-mail address: bichuetti@unifesp.br (D.B. Bichuetti). 1 Denis Bernardi Bichuetti contributed with study conception and design, acquisition of data, analysis and interpretation and critical revision of the manuscript for important intel- lectual content. 2 Marcelo Delboni Lemos contributed with acquisition of data, analysis and interpretation. 3 Isaac de Castro contributed with analysis and interpretation. 4 Gustavo Balthazar da Silveira Carvalho contributed with acquisition of data, analysis and interpretation. 5 Renato Sartori de Carvalho contributed with acquisition of data, analysis and interpretation. 6 Nitamar Abdala contributed with study conception and design, acquisition of data, anal- ysis and interpretation and critical revision of the manuscript for important intellectual content. 7 Enedina Maria Lobato de Oliveira contributed with study conception and design, ac- quisition of data, analysis and interpretation and critical revision of the manuscript for im- portant intellectual content. http://dx.doi.org/10.1016/j.jns.2015.06.017 0022-510X/© 2015 Elsevier B.V. All rights reserved. Contents lists available at ScienceDirect Journal of the Neurological Sciences journal homepage: www.elsevier.com/locate/jns