P222 Diagnostic and therapeutic possibilities of transcranial magnetic stimulation in patients after traumatic brain injury

Objectives Recovery of both mental and motor functions is one of the key problems of neurorehabilitation of patients with traumatic brain injury (TBI), accompanied by posttraumatic unconsciousness state (PUS). The purpose of pilot study is to clarify the diagnostic and therapeutic potential of TMS in patients after TBI with impaired motor activity and consciousness. Methods Observation groups: (1) 15 patients after TBI at the age of 17–56, in which the diagnostic TMS (cortical motor areas (M1) bilaterally, CVII bilaterally, registration of MEPs from musculus abductor pollicis brevis) was performed; (2) 9 patients after TBI at the age of 16–44 with a prolonged (from 60 to 220 days) unconscious state in which the rhythmic TMS was performed; (3) Control group: 5 healthy men aged 22–28. Diagnostic TMS evaluated cortical, radicular latency and amplitude of MEPs,time of central motor conduction. In the second and third groups changes of neurological status, indicators of the memory and attention, and N100, N200 and P300 components of auditory ERP hour before and hour after stimulation were estimated. Results Diagnostic TMS in patients with positive or ambiguous clinical dynamics showed initial difference of conductivity of tracts in comparison with normal data by 20–30% or 30–40%, respectively, with progressive improvement as motor and cognitive functions recovered. In patients with negative clinical dynamics TMS values had significantly larger deviation of cortical latency and amplitudes of MEPs (over 45%), and also the time of central motor conduction. Statistical analysis of acquired data revealed the greatest prognostic significance for determining the level of the amplitudes of MEPs with undeniable importance for the indicators of cortical latency and the time of central motor conduction. Therapeutic TMS of the sagittal premotor cortex areas in groups 2 and 3 concurred with improvement of any attention and normalization of amplitude and latency of all ERP components, as well as indicators of their spatial synchronism, especially for P300. Conclusions The obtained data clarifies diagnostic parameters of TMS and proposes the availability of using rTMS for therapeutic purposes in patients with PUS. Supported by RFFI N16-29-08304 .