ИСТИНА

Background and aims:. Chronic disorders of consciousness (DOC), such as VS and MCS, are diagnosed mostly by clinical examination, that carries high risk of misdiagnosis.New tools may help establish level of consciousness in certain cases, as presented here. Methods: Case. A clinically VS patient A., male, 48 y.o., 2 years after intracerebral hemorrhage (CRS-R=10) showed only reflex movements to stimulation, no environment contact and preserved sleep-wake pattern. It was reported recently that presence of default mode network (DMN) signal on rs-fMRI was correlates with the degree of clinical consciousness impairment (Vanhaudenhuyse, 2010). Results: On rs-fMRI (3T) we found activation of DMN areas (mPFC, PCC, LIPC, RIPC) (Fig.1). We also performed TMS-EEG with calculating Perturbational Complexity Index (PCI) - an independently validated promising consciousness metric (Casali, 2014), that allows reliable stratification of unresponsive patients with empirical cutoff level for discrimination between the unconscious and conscious states of 0.31 (Casarotto, 2016). We found out high complexity of the cortical response for the TMS stimuli, with PCI of 0.345 for frontal region stimulation (Fig.2) and 0.424 for parietal region (Fig.3) stimulation which implies the «conscious» state in this patient Conclusion: novel diagnostic techniques may reveal patients with possible higher level of consciousness than seen clinically. Such patients should become subject for further investigation to find out the cause of discrepancy between clinical and neurophysiological results, as well as for intensive rehabilitation interventions. Disclosure: The study is supported by Russian Scientific Foundation grant №16-15-00274