title: Diffusion tensor fiber tracking in patients with central post-stroke pain; correlation with efficacy of repetitive transcranial magnetic stimulation.
abstract: Central post-stroke pain (CPSP) is one of the most common types of intractable pain. We reported that repetitive transcranial magnetic stimulation (rTMS) of primary motor cortex relieves pain for patients who were refractory to medical treatment. But the mechanism is unclear. In the present study, we investigated relations between the characteristics of CPSP and the results of fiber tracking, which is the only noninvasive method of evaluating the anatomical connectivity of white matter pathways. Fiber tracking of the corticospinal tract (CST) and thalamocortical tract (TCT) was investigated in 17 patients with CPSP. The stroke lesion was located in a supratentorial region in all cases (corona radiata, one case; thalamus, seven cases; putamen, nine cases). Relations between the delineation ratio (defined as the ratio of the cross section of the affected side to that of the unaffected side) of the CST and of the TCT, manual muscle test score, pain score, region of pain, and efficacy of rTMS were evaluated. Fiber tracking was successful in 13 patients with the stroke lesion involving the TCT. The rTMS-effective group had higher delineation ratio of the CST (p=0.02) and the TCT (p=0.005) than the rTMS-ineffective group. Previous studies suggested that an intact CST allows pain control but did not discuss the TCT. Our results suggest that the TCT also plays a role in pain reduction by rTMS of the primary motor cortex and that the efficacy of rTMS for patients with CPSP is predictable by fiber tracking.
authors.affiliation: Department of Neurosurgery, Osaka University Graduate School of Medicine, 2-2 E6 Yamadaoka, Suita, Osaka 565-0021, Japan.
authors.forename: Tetsu
authors.initials: T
authors.lastname: Goto
authors.forename: Youichi
authors.initials: Y
authors.lastname: Saitoh
authors.forename: Naoya
authors.initials: N
authors.lastname: Hashimoto
authors.forename: Masayuki
authors.initials: M
authors.lastname: Hirata
authors.forename: Haruhiko
authors.initials: H
authors.lastname: Kishima
authors.forename: Satoru
authors.initials: S
authors.lastname: Oshino
authors.forename: Naoki
authors.initials: N
authors.lastname: Tani
authors.forename: Koichi
authors.initials: K
authors.lastname: Hosomi
authors.forename: Ryusuke
authors.initials: R
authors.lastname: Kakigi
authors.forename: Toshiki
authors.initials: T
authors.lastname: Yoshimine
mesh_terms: D000328:Adult; D000368:Aged; D001931:Brain Mapping / Q000379:methods*; D002540:Cerebral Cortex / Q000473:pathology / Q000503:physiopathology; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D020772:Internal Capsule / Q000473:pathology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000502:physiology; D009434:Neural Pathways / Q000473:pathology / Q000503:physiopathology; D017063:Outcome Assessment, Health Care / Q000379:methods; D010147:Pain Measurement; D010148:Intractable Pain / Q000503:physiopathology / Q000628:therapy*; D011712:Pyramidal Tracts / Q000473:pathology / Q000503:physiopathology; D020521:Stroke / Q000150:complications / Q000473:pathology*; D013788:Thalamus / Q000473:pathology / Q000503:physiopathology; D050781:Transcranial Magnetic Stimulation / Q000379:methods*; D016896:Treatment Outcome