Central motor conduction studies in patients with Guillain Barré syndrome

To study the central nervous system involvement in Guillain Barre (GB) syndrome, 30 patients with GB syndrome were subjected to clinical evaluation, muscle testing as per Medical Research Council (MRC) scale, disability score on a 0-5 scale and central motor conduction studies to abductor digiti minimum (ADM), abductor pollicis bravis (APB) and tibialis anterior (TA) bilaterally. Outcome was defined at the end of 3 months into complete, partial and poor. Their age ranged between 12 and 61 years (mean 3.2) and 11 of them were females. At the peak of weakness, the limb muscle power was grade 0 in 8, grade I-II in 10 and grade III-IV in 12 patients. Grade 5 disability was present in 12, grade 4 in 12 and grade 3 in 6 patients. One of these patients had grade 3 muscle power. Central motor conduction time (CMCT) correlated with muscle power, disability score and outcome. Two of our patients expired during the acute stage and 23 could be followed up till 3 months. Three patients recovered completely, 15 partially and 5 had poor recovery. It can be concluded that mild prolongation of CMCT although occurs frequently in the patients with GB syndrome, however, pronounced slowing of CMCT is rare and may suggest central involvement.