Molding the sensory cortex: spatial acuity improves after botulinum toxin treatment for cervical dystonia.
Disorganization of sensory cortical somatotopy has been described in adult onset primary torsion dystonia (AOPTD). Although botulinum toxin type A (BTX-A) acts peripherally, some studies have suggested a central effect. Our primary hypothesis was that sensory cortical reorganization occurs after BTX-A treatment of AOPTD. Twenty patients with cervical dystonia and 18 healthy age-matched control patients had spatial discrimination thresholds (SDTs) measured at baseline and monthly for 3 months. Mean baseline SDT (+/-SD) was 1.75 +/-0.76 mm in the dystonia group, greater than the control group mean of 1.323 +/- 0.45 mm (P = 0.05). Mean control group SDT did not vary significantly over time. A transient improvement of 23% from baseline (P = 0.005) occurred in the dystonia group 1 month after injection, which did not positively correlate with changes in physician and patient ratings of torticollis severity. The presumed mechanism of SDT improvement is a modulation of afferent cortical inputs from muscle spindles. Society.
Walsh
Richard
R
Department of Neurology, St. Vincent's University Hospital, Dublin, Ireland. richardawalsh@gmail.com
Hutchinson
Michael
M
D000328:Adult; D000368:Aged; D019274:Botulinum Toxins, Type A / Q000627:therapeutic use*; D004192:Discrimination, Psychological / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009949:Orientation / Q000502:physiology; D011597:Psychomotor Performance / Q000502:physiology; D013003:Somatosensory Cortex / Q000187:drug effects*; D013028:Space Perception / Q000502:physiology*; D014103:Torticollis / Q000188:drug therapy* / Q000503:physiopathology / Q000523:psychology*
D019274:Botulinum Toxins, Type A