DIAGNOSTIC SIGNIFICANCE OF NEUROPHYSIOLOGICAL AND STRUCTURAL-HEMODYNAMIC CHANGES IN HEMIFACIAL SPASM

Abstract

The article presents the results of the authors’ own research devoted to a comprehensive assessment of clinical-neurological, neurophysiological, and structural-hemodynamic changes in patients with hemifacial spasm, as well as to determining their diagnostic significance and relationship with disease severity. Objective. To identify the clinical-neurophysiological and structural-hemodynamic features of hemifacial spasm and to determine the most informative criteria for differentiated patient assessment and optimization of the diagnostic approach. Materials and Methods. A total of 126 individuals were examined, including 96 patients with clinically confirmed hemifacial spasm and 30 individuals in the control group. The main group included 47 patients, while the comparison group included 49 patients. Clinical and neurological assessment of hemifacial spasm was performed using the Jankovic Rating Scale, HFS score, HFS-7, and the Sunnybrook system. Facial nerve function was evaluated by electroneuromyography, LSR/AMR recording, blink reflex assessment, and surface electromyography. Structural changes were assessed by ultrasound, while neurovascular conflict was evaluated using MRI and MR angiography. Results. Patients with hemifacial spasm showed marked clinical-neurological, neurophysiological, and structural-hemodynamic differences compared with the control group. LSR/AMR was recorded in 83.0% of patients in the main group and in 81.6% of patients in the comparison group, compared with 3.3% in the control group. The surface EMG asymmetry index exceeded control values by more than fourfold, the frequency of pathological discharges by more than elevenfold, and the pathological coactivation index by approximately 4.5-fold. The diameter of the facial nerve on the affected side was approximately 23–24% greater than in the control group, while the nerve asymmetry coefficient was 22–23% higher. Neurovascular contact was detected in approximately 80% of patients with hemifacial spasm, while neurovascular conflict accompanied by nerve root deformation was identified in nearly half of the patients. Conclusion. Hemifacial spasm is characterized by pathological excitability of the facial nerve, impaired brainstem reflex mechanisms, marked asymmetry of the bioelectrical activity of the facial muscles, and structural-hemodynamic changes in the facial nerve. Integration of clinical, neurophysiological, ultrasound, and neuroimaging parameters allows patients to be stratified and provides a rationale for the scope of additional diagnostic procedures and further treatment strategy.