Individual Detection of Patients with Parkinson Disease using Support Vector Machine Analysis of Diffusion Tensor Imaging Data: Initial Results

• Published in: American journal of neuroradiology : AJNR 2012-12, Vol.33 (11), p.2123-2128
• Main Authors: HALLER, S, BADOUD, S, NGUYEN, D, GARIBOTTO, V, LOVBLAD, K. O, BURKHARD, P. R
• Format: Article
• Language: English
• Subjects: Aged; Algorithms; Biological and medical sciences; Brain; Brain - pathology; Degenerative and inherited degenerative diseases of the nervous system. Leukodystrophies. Prion diseases; Diffusion Magnetic Resonance Imaging - methods; Female; Humans; Image Enhancement - methods; Image Interpretation, Computer-Assisted - methods; Investigative techniques, diagnostic techniques (general aspects); Male; Medical sciences; Nervous system; Neurology; Parkinson Disease - diagnosis; Pattern Recognition, Automated - methods; Pilot Projects; Radiodiagnosis. Nmr imagery. Nmr spectrometry; Reproducibility of Results; Sensitivity and Specificity; Support Vector Machine
• ISSN: 0195-6108; 1936-959X
• DOI: 10.3174/ajnr.A3126

Brain MR imaging is routinely performed in the work-up of suspected PD, yet its role is essentially limited to the exclusion of other pathologies. We performed a pattern-recognition analysis based on DTI data to detect subjects with PD at the individual level. We included 40 consecutive patients with Parkinsonism suggestive of PD who had DTI at 3T, brain (123)I ioflupane SPECT (DaTSCAN), and extensive neurologic testing including follow-up (17 PD: age range, 67.8 ± 6.7 years; 9 women; 23 Other: consisting of atypical forms of Parkinsonism; age range, 67.2 ± 9.7 years; 7 women). Data analysis included group-level TBSS and individual-level SVM classification. At the group level, patients with PD versus Other had spatially consistent increase in FA and decrease in RD and MD in a bilateral network, predominantly in the right frontal white matter. At the individual level, SVM correctly classified patients with PD at the individual level with accuracies up to 97%. Support vector machine-based pattern recognition of DTI data provides highly accurate detection of patients with PD among those with suspected PD at an individual level, which is potentially clinically applicable. Because most suspected subjects with PD undergo brain MR imaging, already existing MR imaging data may be reused; this practice is very cost-efficient.