OBJECTIVE: To investigate transcranial magnetic stimulation (TMS) measures as clinical correlates and longitudinal markers of amyotrophic lateral sclerosis (ALS). METHODS: We prospectively studied 60 patients with ALS subtypes (sporadic ALS, familial ALS, progressive muscular atrophy, and primary lateral sclerosis) using single pulse TMS, recording from abductor digiti minimi (ADM) and tibialis anterior (TA) muscles. We evaluated three measures: 1) TMS motor response threshold to the ADM, 2) central motor conduction time (CMCT), and 3) motor evoked potential amplitude (correcting for peripheral changes). Patients were evaluated at baseline, compared with controls, and followed every 3 months for up to six visits. Changes were analyzed using generalized estimation equations to test linear trends with time. RESULTS: TMS threshold, CMCT, and TMS amplitude correlated (p < 0.05) with clinical upper motor neuron (UMN) signs at baseline and were different (p < 0.05) from normal controls in at least one response. Seventy-eight percent of patients with UMN (41/52) and 50% (4/8) of patients without clinical UMN signs had prolonged CMCT. All three measures revealed significant deterioration over time: TMS amplitude showed the greatest change, decreasing 8% per month; threshold increased 1.8% per month; and CMCT increased by 0.9% per month. CONCLUSIONS: Transcranial magnetic stimulation (TMS) findings, particularly TMS amplitude, can objectively discriminate corticospinal tract involvement in amyotrophic lateral sclerosis (ALS) from controls and assess the progression of ALS. While central motor conduction time and response threshold worsen by less than 2% per month, TMS amplitude decrease averages 8% per month, and may be a useful objective marker of disease progression.
OBJECTIVE: To investigate transcranial magnetic stimulation (TMS) measures as clinical correlates and longitudinal markers of amyotrophic lateral sclerosis (ALS). METHODS: We prospectively studied 60 patients with ALS subtypes (sporadic ALS, familial ALS, progressive muscular atrophy, and primary lateral sclerosis) using single pulse TMS, recording from abductor digiti minimi (ADM) and tibialis anterior (TA) muscles. We evaluated three measures: 1) TMS motor response threshold to the ADM, 2) central motor conduction time (CMCT), and 3) motor evoked potential amplitude (correcting for peripheral changes). Patients were evaluated at baseline, compared with controls, and followed every 3 months for up to six visits. Changes were analyzed using generalized estimation equations to test linear trends with time. RESULTS: TMS threshold, CMCT, and TMS amplitude correlated (p < 0.05) with clinical upper motor neuron (UMN) signs at baseline and were different (p < 0.05) from normal controls in at least one response. Seventy-eight percent of patients with UMN (41/52) and 50% (4/8) of patients without clinical UMN signs had prolonged CMCT. All three measures revealed significant deterioration over time: TMS amplitude showed the greatest change, decreasing 8% per month; threshold increased 1.8% per month; and CMCT increased by 0.9% per month. CONCLUSIONS: Transcranial magnetic stimulation (TMS) findings, particularly TMS amplitude, can objectively discriminate corticospinal tract involvement in amyotrophic lateral sclerosis (ALS) from controls and assess the progression of ALS. While central motor conduction time and response threshold worsen by less than 2% per month, TMS amplitude decrease averages 8% per month, and may be a useful objective marker of disease progression.
Authors: W J Triggs; D Menkes; J Onorato; R S Yan; M S Young; K Newell; H W Sander; O Soto; K H Chiappa; D Cros Journal: Neurology Date: 1999-08-11 Impact factor: 9.910
Authors: H Mitsumoto; A M Ulug; S L Pullman; C L Gooch; S Chan; M-X Tang; X Mao; A P Hays; A G Floyd; V Battista; J Montes; S Hayes; S Dashnaw; P Kaufmann; P H Gordon; J Hirsch; B Levin; L P Rowland; D C Shungu Journal: Neurology Date: 2007-04-24 Impact factor: 9.910
Authors: Michael Benatar; Kevin Boylan; Andreas Jeromin; Seward B Rutkove; James Berry; Nazem Atassi; Lucie Bruijn Journal: Muscle Nerve Date: 2015-12-29 Impact factor: 3.217
Authors: John Ravits; Stanley Appel; Robert H Baloh; Richard Barohn; Benjamin Rix Brooks; Lauren Elman; Mary Kay Floeter; Christopher Henderson; Catherine Lomen-Hoerth; Jeffrey D Macklis; Leo McCluskey; Hiroshi Mitsumoto; Serge Przedborski; Jeffrey Rothstein; John Q Trojanowski; Leonard H van den Berg; Steven Ringel Journal: Amyotroph Lateral Scler Frontotemporal Degener Date: 2013-05 Impact factor: 4.092