[Long-latency components (N100, N200 and P300) of acoustic evoked potentials in prediction of mental recovery in severe traumatic brain injury].

The authors analyzed correlations of amplitude and latency levels of N100, N200 and P300 components of acoustic evoked potentials (AEP) registered during sonic stimulation and counting of target-oriented stimuli in 22 patients in vegetative state and mutism as an outcome of traumatic brain injury. Results were analyzed with association of electrophysiological findings with data of diffusion-tensor MRI. 55 healthy volunteers were included into control group. It is described that patients in vegetative state with formal recovery to the level of clear consciousness develop all three components of AEP in response to target-oriented tone. The instruction "to counts" leads to their better development. Patients with restoration to minimal level of consciousness produce all components during audition of sounds and only N100 and N200 in response to standard tone after instruction "to count". It is discovered that levels of amplitude have bigger correlation according to Spearman's criterion with outcome in comparison to latency. There changes are more prominent in N100 and N200 components rather in P300. In addition, after instruction "to count sounds" the registered changes between stages of vegetative state and mutism are significant for leads of left hemisphere, and during audition of sounds--for sagittal leads. The study showed correspondence of acquired changes with MRI data. Chronic unconscious state is associated with changes in corpus callosum (degeneration fibers) and corticospinal tracts in the brainstem. The data are discussed in light of hypothesis of the role of morphofunctional disconnections (brainstem-thalamus and interhemispheric) in impairment of attention and in genesis of different forms of posttraumatic unconscious state.

[Experience in surgical treatment of patients with focal forms of temporal epilepsy]. / Opyt khirurgicheskogo lecheniia bol;nykh s ochagovymi formami visochnoi épilepsii.

Fifteen patients with focal lesions of temporal epilepsy were examined before and 6 months to 4 years after surgery. There were low-grade gliomas in 13 cases, muscle tissue heterotopy in 1 case, and medial temporal sclerosis in 1. Epileptogenic lesions were localized in the medial structures of the temporal lobe in 10 cases and in the lateral temporal regions in 5 cases. Comprehensive neurophysiological study, including intraoperative electrocorticography, was used to identify an epileptogenic zone (EZ). EZs were found in the medial structures on the affected side in all patients. Lesionectomies were performed in all cases. It was combined with medial resection in 12 cases (it was done in 10 patients until epileptic activity disappeared). Nine patients stopped having seizures after surgery. One patient had only auras. Improvements were slight in 5 patients. A relationship was found between the surgical outcomes and the site of a lesion and EZ. They authors conclude that complete recovery may occur in cases with medial locations of a lesion and EZ. The outcomes of surgery are much poorer in cases with the lateral sites of an lesion and in those with the medial site of EZ.