title: Predicting outcome in clinically isolated syndrome using machine learning.
abstract: We aim to determine if machine learning techniques, such as support vector machines (SVMs), can predict the occurrence of a second clinical attack, which leads to the diagnosis of clinically-definite Multiple Sclerosis (CDMS) in patients with a clinically isolated syndrome (CIS), on the basis of single patient's lesion features and clinical/demographic characteristics. Seventy-four patients at onset of CIS were scanned and clinically reviewed after one and three years. CDMS was used as the gold standard against which SVM classification accuracy was tested. Radiological features related to lesional characteristics on conventional MRI were defined a priori and used in combination with clinical/demographic features in an SVM. Forward recursive feature elimination with 100 bootstraps and a leave-one-out cross-validation was used to find the most predictive feature combinations. 30 % and 44 % of patients developed CDMS within one and three years, respectively. The SVMs correctly predicted the presence (or the absence) of CDMS in 71.4 % of patients (sensitivity/specificity: 77 %/66 %) at 1 year, and in 68 % (60 %/76 %) at 3 years on average over all bootstraps. Combinations of features consistently gave a higher accuracy in predicting outcome than any single feature. Machine-learning-based classifications can be used to provide an "individualised" prediction of conversion to MS from subjects' baseline scans and clinical characteristics, with potential to be incorporated into routine clinical practice.
authors.affiliation: NMR Research Unit, UCL Institute of Neurology, Queen Square MS Centre, Queen Square, London, UK ; Department of Computer Science, Centre for Medical Imaging Computing, UCL, London, UK.
authors.forename: V
authors.initials: V
authors.lastname: Wottschel
authors.affiliation: Department of Computer Science, Centre for Medical Imaging Computing, UCL, London, UK.
authors.forename: D C
authors.initials: DC
authors.lastname: Alexander
authors.affiliation: Department of Computer Science, Centre for Medical Imaging Computing, UCL, London, UK.
authors.forename: P P
authors.initials: PP
authors.lastname: Kwok
authors.affiliation: NMR Research Unit, UCL Institute of Neurology, Queen Square MS Centre, Queen Square, London, UK ; National Institute for Health Research (NIHR), University College London Hospital (UCLH), Biomedical Research Centre (BRC), UK.
authors.forename: D T
authors.initials: DT
authors.lastname: Chard
authors.affiliation: Department of Neurological and Behavioral Sciences, University of Siena, Siena, Italy.
authors.forename: M L
authors.initials: ML
authors.lastname: Stromillo
authors.affiliation: Department of Neurological and Behavioral Sciences, University of Siena, Siena, Italy.
authors.forename: N
authors.initials: N
authors.lastname: De Stefano
authors.affiliation: NMR Research Unit, UCL Institute of Neurology, Queen Square MS Centre, Queen Square, London, UK ; National Institute for Health Research (NIHR), University College London Hospital (UCLH), Biomedical Research Centre (BRC), UK.
authors.forename: A J
authors.initials: AJ
authors.lastname: Thompson
authors.affiliation: NMR Research Unit, UCL Institute of Neurology, Queen Square MS Centre, Queen Square, London, UK ; National Institute for Health Research (NIHR), University College London Hospital (UCLH), Biomedical Research Centre (BRC), UK.
authors.forename: D H
authors.initials: DH
authors.lastname: Miller
authors.affiliation: NMR Research Unit, UCL Institute of Neurology, Queen Square MS Centre, Queen Square, London, UK ; National Institute for Health Research (NIHR), University College London Hospital (UCLH), Biomedical Research Centre (BRC), UK.
authors.forename: O
authors.initials: O
authors.lastname: Ciccarelli
mesh_terms: D000328:Adult; D003711:Demyelinating Diseases / Q000175:diagnosis*; D018450:Disease Progression; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000175:diagnosis*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D060388:Support Vector Machine; D055815:Young Adult
keywords: Clinically isolated syndrome; MRI; Multiple Sclerosis; Support vector machines