Evaluation of Doppler and electroencephalographic changes in patients with postconcussion syndrome due to mild blast traumatic brain injury

Abstract

Mild blast traumatic brain injury (mbTBI) often remains undiagnosed and untreated due to lack of treatment of patient, imperfect screening tools, unclear diagnostic criteria, and lack of means to objectify or visualize the injury. Objective: to investigate Doppler and electroencephalographic changes in patients with postconcussion syndrome (PCS) due to mbTBI and the possibility of their use to objectify the injury. Materials and methods. The study involved 115 male participants of hostilities in the East Ukraine (main group) with a diagnosis of "PCS after previous mbTBI" and 30 healthy individuals (control group). Patients were in the long-term period of injury (from 6 months to 3 years). After collecting complaints and history data, the neurological status and the state of cognitive functions were examined. Neuropsychological testing according to the Montreal cognitive assessment score was carried out. Ultrasound duplex scanning with color Doppler mapping of neck and head vessels and transcranial duplex scanning were performed. Quantitative electroencephalography was performed according to standard parameters (sensitivity - 70 μV / cm, time constant - 0.1 s, filter - 40 Hz). Results. In patients with PCS after mbTBI, transcranial duplex scanning can detect changes in vascular resistance in the intracranial vessels of both the carotid and vertebrobasilar basins (mostly reduced resistance values), as well as signs of venous discirculation in the basal veins of the brain, quantitative electroencephalography – changes in the frequency and topic of the α-rhythm, a decrease in its amplitude, frequency-spatial inversion, the presence of signs of dysfunction of nonspecific brain structures, according to spectral analysis – a decrease in α-power, an increase in β-power, activity in θ- and δ-bands. Conclusions. Detected Doppler and electroencephalographic changes may persist in the long-term period of mbTBI. They should be taken into account in the differential diagnosis of post-traumatic stress disorder.