Electroencephalographic Markers of Lateral Shifts of Brain Midline Structures in Patients With Acute Spontaneous Supratentorial Intracerebral Haemorrhage

Abstract

The aim of this study is to improve the diagnostic approaches in acute period of spontaneous supratentorial intracerebral hemorrhage by detecting the most informative parameters of spectral analysis of the electroencephalographic pattern in the evaluation of cerebral bioelectrical activity changes caused by the lateral shifts of brain midline structures. Materials and methods. We carried out clinical and paraclinical examination of 156 patients (90 men and 66 women, mean age 66,7±0,8 years) with firstly appeared hypertensive spontaneous supratentorial intracerebral hemorrhage. The diagnosis was based on the findings of computed tomography. Lateral shift was evaluated as an average from septum pellucidum and pineal gland displacements. Clinical neurological investigation included the evaluation according to the National Institute of Health Stroke Scale. Computed electroencephalography was carried out within the first 48 hours from the disease onset. Spectral rhythm power, fronto-occipital gradients, interhemispheric rhythm asymmetry parameters were analyzed. Statistical processing included evaluating differences between the groups studied, logistic regression analysis, ROC-analysis. Results. No lateral shift of brain midline structure was found in 57 (36.5%) patients; lateral shift ranged from 1-5mm was diagnosed in 72 (46.2%) patients; the lateral shift over 5 mm was found in 27 (17.3%) patients. We have found out the following values can be used as electroencephalographic criteria of lateral shift of brain midline structures: values of relative spectral power rhythm of alpha band ≤20,5% in affected hemisphere (Se=79,8%, Sp=77,2%) and ≤17,7% in intact hemisphere (Se=71,7%, 75,4%), fronto-occipital rhythm gradients of alpha2 band >–0,085 in affected hemisphere (Se=71,7%, Sp=63,2%) and >–0,266 in intact hemisphere (Se=80,8%, Sp=54,4%), while relative spectral rhythm power of delta band >48,4% in affected hemisphere (Se=88,9%, Sp=74,2%) and >46,8% in intact hemisphere (Se=92,6%, Sp=72,4%), fronto-occipital rhythm gradients of alpha band >–0,001 in affected hemisphere (Se=81,5%, Sp=65,1%). These values demonstrate disturbances in cerebral bioelectrical activity caused by lateral shift over 5 mm. Conclusions. The values of relative spectral rhythm power and fronto-occipital rhythm gradients of alpha band in affected and intact hemispheres are the most informative parameters of spectral electroencephalographic pattern analysis for detection of bioelectrical brain activity deteriorations caused by the lateral shift of brain midline structure due to acute spontaneous supratentorial intracerebral haemorrhage.