Pilot feasibility study of a semi-automated three-dimensional scoring system for cervical dystonia.

The objective of this study is to test the feasibility of a semi-automated scoring system for the Toronto Western Spasmodic Torticollis Scale (TWSTRS) severity scale in patients with cervical dystonia. The TWSTRS requires training and experience. We previously developed a system to measure neck angle by analyzing three-dimensional position, obtained using Kinect, a marker-less three-dimensional depth sensor. The system can track patients' faces and bodies, automatically analyze neck angles, and semi-automatically calculate the TWSTRS severity scale score. We compared the TWSTRS severity scale scores calculated by the system with the video-based scores calculated by a neurologist trained in movement disorders. A correlation coefficient analysis was then conducted. Absolute accuracy was measured using intra-class correlation (ICC) (3,1), with 95% limits of agreement. To analyze the subscales, Cohen's kappa coefficient (κ) was calculated. A p-value of < .05 was considered statistically significant. Thirty patients were enrolled. Their average age was 52.3±16.0 years, and the male to female ratio was 3:2. The average disease duration was 11.3±12.7 years. Total score measurements by the system were significantly correlated with those rated by the movement disorder-trained neurologist (r = .596, p < .05). There was a significant correlation (r = .655, p < .05) with regard to the automated part of the scale. An adequate ICC (3,1) of .562 was obtained for total severity score (p < .001, 95% confidence interval [CI]: .259-.765), while the equivalent score was .617 for the total automated part (p < .001, 95% CI .336-.798). Our three-dimensional motion capture system, which can measure head angles and semi-automatically calculate the TWSTRS severity scale score utilizing a single-depth camera, demonstrated adequate validity and reliability. This low-cost and portable system could be applied by general practitioners treating cervical dystonia to obtain objective measurements.

Déclaration de conflit d'intérêts

NH has received speaker honoraria from Dai-Nippon Sumitomo, Otsuka, Takeda, Kyowa Hakko-Kirin, GSK, Nippon Boehringer Ingelheim, FP, Eisai, Kissei, Nihon Medi-physics, Novartis, Biogen Idec Japan, AbbVie, Astellas, Boston Scientific Japan, Sanofi, Pfizer Japan, Alexion, Mylan N.V, MSD, Daiichi Sankyo, and MDS. NH has received consultancies and subcontracting from Dai-Nippon Sumitomo, Biogen Idec, Otsuka, Takeda, Kyowa Hakko-Kirin, Meiji Seika, Hisamitsu, Kao. GO has received speaker honoraria from Medtronic, Boston Scientific, Otsuka Pharmaceutical, Sumitomo Dainippon Pharma, Novartis Pharma, MSD, Nihon Medi-Physics, FP Pharmaceutical Corporation, and Kyowa Hakko Kirin, and Abbvie. There are no patents, products in development or marketed products to declare. This does not alter the authors' adherence to PLOS ONE policies on sharing data and materials.