Aim: study of threshold ratios between indicators of acoustic impedance and threshold tonal audiometry in military personnel – participants in hostilities. Materials and methods: the results of audiometric and impedancemetric examinations of 43 servicemen aged 18 to 42 years who received combat acute trauma in the period March-August 2022 and 20 patients with severe sensorineural deafness (2, 3, 4 stages according international classification) of non-acutraumatic genesis as a comparison group. Results and their discussion: During the examination of 43 soldiers, it was found that with significant sensorineural hearing loss on both sides (3 and 4 stages according international classification), the patients registered a full-fledged acoustic reflex during ipsilateral and contralateral stimulation. When conducting an impedanceometric examination of patients in the comparison group, it was found that in most patients the acoustic reflex was not registered at all. Conclusions: 1. In combat acute acoustic trauma, it is possible to register acoustic middle-ear-muscle reflex with severe hearing loss, which may be caused by damage to the receptor part of the auditory analyzer and the accompanying symptom of the phenomenon of accelerated loudness, by a central mechanism, or by a combination of central and peripheral mechanisms. 2. Dissociation of acoustic middle-ear-muscle reflex threshold values and threshold tonal audiometry is a characteristic feature of acutraumatic damage to the auditory analyzer. 3. Identified features, such as registration of acoustic middle-ear-muscle reflex in severe hearing loss, dissociation of acoustic reflex thresholds and tonal audiometry may be useful for further study of the pathogenesis of combat acute trauma, which, in turn, will contribute to improving the quality of diagnosis and finding ways to correct disorders of the auditory system in individuals, who suffered as a result of hostilities.

The active combat actions in our country resulted in the increasing the risk of occurrence of the acoustics trauma, acubarotrauma. There is an increase of number of cases of combat acoustic trauma in servicemen and now this problem acquires a large value. The objective estimation of cerebral hemodynamics in patients with acoustics trauma, got in battle conditions, is a necessary condition for the effective complex treatment of sensorineural violations of hearing in such patients. Aim: the examination of quantitative and qualitative indexes of rheoencephalography before and after the treatment of the sensorineural hearing loss (SNL) that is accompanied by violations in the central departments of auditory analyzer, in servicemen that got acoustic trauma in the real combat terms. Materials and methods: The 52 servicemen with acoustic trauma and 15 healthy persons were inspected. There were analyzed 67 rheoencephalograms. Examinations were conducted by means of computer rheography firm "DX systems". Results and their discussions: During the quality estimation of rheograms of the inspected patient’s violation of circulation of blood of cerebrum was educed both in the carotid (FM) and in vertebral-basilar (OM) systems. Before the beginning of treatment, the normal indexes of the state of cerebral circulation of blood by data of REG did not register in any patient with acoustic trauma. The difficulty of venous outflow took place in 69,0% cases in the carotid system and in 87,0% in vertebral-basilar system. Among the investigated patients we also registered the decline of tone of cerebral vessels (15,0%) and cases of atony curve (23,0%). Only in 14,0% examined fighters we found the increase of tone of cerebral vessels with the phenomena of angiospasm. There was the considerable part of patients with unsteady vascular tone with inclination to the increase (41,0%) or decline (18,0%) in both systems of cerebral circulation of blood. In relation to the pulse blood filling, in patients with acoustic trauma there was more than half (51,0%) cases with its decline in the carotid system and (77,0%) in a vertebral-basilar pool. In the vertebral-basilar system in patients with acoustic trauma there was also marked asymmetry of REG-curves (13,0%). After the treatment the improvement of quality indexes of REG took place. In the carotid system the percent of registration of unsteady vascular tone went down with inclination to the decline and cases of atony curve. The patients with acoustic trauma after treatment had less of cases (33,0%) of declines of the pulse blood filling in the carotid system. The percent of asymmetry of REG-curves diminished also (3,0%) in both systems of cerebral circulation of blood. In the inspected patients the changes of tone of cerebral vessels and difficulty of venous outflow, and also the declines of the pulse blood filling, took place both in carotid and in vertebral-basilar systems. This got the reflection in the quantitative indexes of REG: the changes of indexes α, dicrotic (DCi), diastolic (DSi) and rheographic (Rі) indexes of REG-curve in both systems of cerebral blood supply. Conclusions: The treatments of servicemen, that got acoustic trauma in the zone of battle actions must be as possible quicker and complex taking into account the data of audiometry and instrumental inspections, the cerebral circulation of blood. Patients with acoustic trauma have unsteady or decreased tone of cerebral vessels, atony curve, fall-off of the pulse blood filling, difficulty of venous outflow. The most informing quantitative indexes of REG are DCi, DSi and Rі, that represent the presence of such changes of cerebral hemodynamics. Conducted studies showed considerable violations of cerebral circulation of blood both in carotid and, especially, in the vertebral-basilar system in patients with acoustic trauma, got in the real battle terms. The servicemen with battle acoustic trauma should be treated straightaway with the presence of initial sensorineural violations, it is necessary in time to begin a complex treatment taking into account the state of the auditory system and extra aural changes, first of all the cerebral circulation of blood. It will allow to warn the progression of auditory violations and forming the heavy sensorineural hearing loss. The results of the objective state of cerebral circulation of blood for fighters with acoustic trauma can be useful in expertise questions.

Topicality: The research conducted by the authors shows that acute trauma in combat conditions is accompanied by persistent psychophysiological disorders of the central nervous system, but a significant part of these studies is based on clinical observation data. The technique of electroencephalography (EEG) allows you to objectively assess the state of the central nervous system and provides a better understanding of neurophysiological processes in patients with sensorineural deafness (SND) with acute trauma, which will contribute to the development of more effective rehabilitation methods for this contingent of patients. Aim: to evaluate the indicators of bioelectrical activity of the brain according to electroencephalography (EEG) data in servicemen who received acute trauma in real combat conditions, with different effectiveness of treatment measures. Materials and methods: 2 groups of servicemen with combat acute trauma were examined: 1 group - patients with positive dynamics of treatment, 2 group - patients with insufficient effectiveness of treatment, and 15 healthy normal-sensing individuals of the control group. The electroencephalographic study was carried out with the help of a computer electroencephalograph of the company "DH-systems" (Ukraine). Results: All patients underwent a comprehensive, instrumental examination. The examined subjects had sensorineural deafness with a descending, often abrupt, type of tonal audiometric curve, with the most pronounced and reliable increase in hearing sensitivity thresholds in the region of 4, 6, and 8 kHz. According to the analysis of EEG indicators, in the patients examined by us, the most characteristic were a decrease in the bioelectric activity of the brain and disorganization of cortical rhythms with signs of dysfunction of the diencephalon-stem structures. At the same time, the decrease in bioelectric activity most often occurred in the frontal and temporal leads. Thus, in patients of group 1, during the background recording, the content of the delta rhythm was (13,61±0,37) and (9,96±0,29) %, respectively, which significantly exceeds the control indicators (8,5±1,6) and (5,3±1,5) % (Р<0,05). During photostimulation and hyperventilation in the frontal leads, the content of slow-wave activity significantly exceeded the control indicators. During photostimulation, the content of the delta rhythm in patients of group 1 was (14,23±0,38) and (7,3±1,4) % in the control group. In the comparative analysis of EEG indicators between the studied groups, an increase in the representation of slow-wave activity in frontal projections and a decrease in the share of alpha rhythm in patients of group 2 is noted. Thus, in frontal leads during background recording in patients of groups 1 and 2, the delta rhythm content was (13,61±0,37) and (16,95±0,25) %, respectively. Moreover, these trends were preserved both during background recording and during functional loads. Therefore, patients with combat acute trauma have significant disturbances in the bioelectrical activity of the brain according to EEG data. Patients with pronounced disorders of the functional state of the central nervous system are more difficult to treat with SNP. Conclusions: 1. Military personnel with acute trauma received in real combat conditions have objective signs of functional disorders in the cortical and deep structures of the brain according to EEG data. 2. Prognostically unfavourable in terms of treatment effectiveness is the redistribution of the main EEG rhythms in the direction of growth of slow-wave activity on a disorganized background, especially in frontal projections. It is advisable to take this into account when carrying out treatment and preventive measures and developing rehabilitation measures. 3. Targeted treatment of sensorineural deafness in patients with combat acute trauma should be carried out taking into account extraural disorders, which allows to prevent the development of severe deafness.

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Topicality: Providing medical care to patients with combat acoustic trauma remains a topical issue of military medicine. There are works in the literature that show changes in the central nervous system under the influence of intense noise and at acoustic trauma, however, only in individual studies this objective assessment of the functional state of the central nervous system in patients with sensorineural hearing loss is shown as well as the promising use of them. Aim: is to determine the most significant indicators of bioelectric activity of the brain according to the EEG in terms of prediction of the course and ways of co-rejection of sensorineural hearing disorders in persons who have received an acute trauma in the area of fighting. Materials and methods: A group of servicemen with acoustic trauma was examined with the most characteristic, typical forms of audiometric curves – with a downward, precipitous type of the curve, which were divided into three groups depending on the degree of severity of sensorineural deafness. Group 1 – patients with initial non-expressed violations of the function of sound perception in the basal part of the cochlea, group 2 – with a more significant SDP accompanied by violations of speech and supra-vocal audiometry, the 3 groups included patients with severe violations of auditory function, lesions of the mediobasal part of the cochlea, often – with a "break" of perception of tones in the conventional range. A total of 205 patients with acoustic trauma were examined. As a control group, 15 healthy normal people were examined. The EEG study was carried out using the computer electroencephalometry of the firm "DX-System" (Ukraine) according to the generally accepted methodology according to the scheme of electrodes "10-20" Results: In qualitative analysis of electroencephalograms, servicemen with combat acoustic trauma revealed deviations from the norm in the functional state of the central nervous system, expressed in varying degrees, with the most characteristic decreasing of the bioelectric activity of the brain, irritative changes, disorganization and desynchronization of rhythms, more often in the temporal and frontal leads. The most significant changes were in patients with more severe hearing impairment (group 3). These changes indicate signs of severe cortex irritation and deep brain structures in servicemen with acoustic trauma from the combat zone. The analysis of EEG quantitative indicators showed that changes in the bioelectric activity of the cerebral brain in patients with acoustic trauma were manifested by deformation of the basic rhythm with modulation and weakened response to functional loads, especially in the anterior leads. Patients had the significantly (P<0,05) decreased percentage of alfa rhythm in the normal picture of the EEG and the increased representation of beta and delta rhythm, both in the background recording and in the functional loading of photostimulations and hyperventilation . The most significant (P<0,05) changes in bioelectric activity, in comparison with the control group, were observed in individuals 2 and, personally, in 3 groups, with more significant violations of auditory function. We also conducted a comparative analysis of EEG quantitative indicators among the study groups. The results of the research indicate a reliable (P<0,05) difference in the indices in the groups, from the first to the third group there was an increase in the representation of delta, theta and beta rhythm, most in the forward projections, and the decrease in the proportion of alpha rhythm. Moreover, these tendencies were maintained both during the background recording and at the functional loads. Conclusions: Thus, the servicemen with an acoustic trauma revealed objective signs of functional disorders in the cortical and deep structures of the brain. As the auditory function decreases in patients with acoustic trauma and redistribution of the main EEG rhythms in the direction of the growth of manifestations of slow-wave activity on a disorganized background occurs, especially in the frontal and temporal infections. In the subjects we surveyed with severe violations of auditory function, there are significantly more significant changes in the central nervous system than in patients with an initial SDE, which should be taken into account when carrying out treatment and preventive measures aimed at rehabilitation of the victims of combat operations with acoustic trauma.