Practical use of electromyography in veterinary medicine – A review

Electromyography (EMG) is a sophisticated electrodiagnostic-neurophysiological method, which serves to diagnose neuromuscular system diseases. It is based on the measurement of the electrical potentials created by the skeletal muscle activity. For this technique, surface electrodes and needle electrodes can be used, which read the action potential of a large number of motor units and read a small number of motor units, respectively. The wide-spectrum application of this method extends our diagnostic possibilities of the clinical examination in veterinary practice. Together with a clinical neurological examination and imaging methods, EMG forms a part of the diagnosis of nervous system diseases and it is a useful diagnostic technique for differentiating neuropathies, junctionopathies, and myopathies. The results of the neurophysiological examination inform us about the functional state of the peripheral and central nervous system; it can demonstrate subclinical diseases and monitor the dynamics of changes in the functional state of individual nervous systems over time. In this article, we review the electromyographic method and its use in veterinary practice.

P.050 Perspectives on the use of ancillary tests for determining neurological death: a survey of Canadian intensivists

Background: Ancillary tests are indicated to diagnose death by neurological criteria whenever clinical neurological examination is unreliable, but their use is variable and subject to debate. Methods: Survey of Canadian intensivists providing care for potential organ donors. We included closed-ended questions and different clinical scenarios regarding the use of ancillary tests. Results: Among 550 identified intensivists, 249 completed the survey. Respondents indicated they would be comfortable diagnosing death based on neurological examination without ancillary tests in the following scenarios: movement in response to stimulation (48%), spontaneous peripheral movement (31%), inability to evaluate upper/lower extremity responses (34%) or both oculocephalic and oculo-caloric reflexes (17%), presence of high cervical spinal cord injury (16%) and within 24 hours of hypoxemic-ischemic brain injury (15%). Furthermore, 93% agreed that ancillary tests should always be conducted when a complete neurological examination is impossible, 89% if there remains possibility of residual sedative effect and 59% in suspected isolated brainstem death. Conclusions: Our findings suggest that Canadian intensivists have different perceptions on what constitutes a complete and reliable clinical neurological examination for determining death by neurologic criteria. Some self-reported practices also diverge from national recommendations. Further investigation and education are required to align and standardize medical practice across physicians and systems.

Evaluation of peripheral amyloid neuropathy

Symptoms of peripheral nervous system (PNS) damage are common clinical manifestations of systemic amyloidosis. Peripheral amyloid neuropathy is characterized by a progressive course, leading to the disability of patients; however, the current possibilities of pathogenetic therapy make the early diagnosis of amyloid neuropathy particularly urgent.Objective: to evaluate the informative value of laser confocal microscopy (LCM) of the cornea in diagnosing small fiber neuropathy of peripheral nerves in patients with systemic amyloidosis.Patients and methods. The study included nine patients (three men and six women) with morphologically confirmed primary amyloidosis (ALamyloidosis) and 12 patients (three men and nine women) with hereditary transthyretin amyloidosis (TTR-amyloidosis) verified by genetic and morphological methods. At baseline, the mean age of patients with AL-amyloidosis was 60.6±10.7 years, with hereditary TTR-amyloidosis – 57.1±13.1 years. According to the history of the disease in AL-amyloidosis, the mean duration of clinical symptoms was 2.7±1.4 years, with TTR-amyloidosis – 5.5±3.6 years. 20 age- and sex-adjusted healthy volunteers were included in the control group. All patients underwent a clinical neurological examination with an assessment of the severity of neuropathy according to the Neuropathy Impairment Score (NIS); 21 patients with systemic amyloidosis and all volunteers of the control group underwent LCM of the corneal nerve fibers (CNF). The coefficients of anisotropy (КΔL) and orientation symmetry (Ksym) of the CNF were calculated to assess the severity of damage to the corneal nerves.Results and discussion. Clinical neurological examination in patients with AL-amyloidosis revealed polyneuropathic syndrome (45%), tunnel syndrome (22%), their combination (22%), and autonomic dysfunction in the form of orthostatic hypotension and impaired motility of the gastrointestinal tract (GI tract; 56%). Symptoms in patients with TTR-amyloidosis were characterized by a combination of tunnel neuropathy and sensory-motor polyneuropathy (50%), distal symmetric polyneuropathy (42%). Frequent symptoms of PNS damage in systemic amyloidosis include autonomic neuropathy (56% – in AL-amyloidosis, 92% – in TTR-amyloidosis) presenting with orthostatic hypotension, impaired gastrointestinal motility, hypohidrosis, and dysuria. The mean NIS score, which characterizes the severity of somatic neuropathy, was significantly higher in patients with TTR-amyloidosis than AL-amyloidosis (p<0.02). LCM of the cornea showed disturbances in the course and structure of the corneal nerve fibers in all examined patients with systemic amyloidosis. The mean anisotropy coefficient values were lower in patients with systemic amyloidosis than in the control group. There were no significant differences in the AL- and TTR-amyloidosis groups. An inverse correlation of average strength between the values of the anisotropy coefficient and NIS was revealed (r=-0.6; p=0.04) in the group of patients with TTR-amyloidosis.Conclusion. Clinical polymorphism of peripheral somatic and autonomic nervous systems lesions is typical for patients with systemic amyloidosis. LCM of the cornea is informative in the diagnosis of small fibers neuropathy of peripheral nerves in systemic amyloidosis; however, it cannot establish the nosology of neuropathy.

Neurodevelopment in Children Exposed to Zika Virus: What Are the Consequences for Children Who Do Not Present with Microcephaly at Birth?

The relation of Zika virus (ZIKV) with microcephaly is well established. However, knowledge is lacking on later developmental outcomes in children with evidence of maternal ZIKV infection during pregnancy born without microcephaly. The objective of this analysis is to investigate the impact of prenatal exposure to ZIKV on neuropsychomotor development in children without microcephaly. We evaluated 274 children including 235 ZIKV exposed and 39 controls using the Bayley-III Scales of Infant and Toddler Development (BSIDIII) and neurological examination. We observed a difference in cognition with a borderline p-value (p = 0.052): 9.4% of exposed children and none of the unexposed control group had mild to moderate delays. The prevalence of delays in the language and motor domains did not differ significantly between ZIKV-exposed and unexposed children (language: 12.3% versus 12.8%; motor: 4.7% versus 2.6%). Notably, neurological examination results were predictive of neurodevelopmental delays in the BSIDIII assessments for exposed children: 46.7% of children with abnormalities on clinical neurological examination presented with delay in contrast to 17.8% among exposed children without apparent neurological abnormalities (p = 0.001). Overall, our findings suggest that relative to their unexposed peers, ZIKV-exposed children without microcephaly are not at considerably increased risk of neurodevelopmental impairment in the first 42 months of life, although a small group of children demonstrated higher frequencies of cognitive delay. It is important to highlight that in the group of exposed children, an abnormal neuroclinical examination may be a predictor of developmental delay. The article contributes to practical guidance and advances our knowledge about congenital Zika.

Features of pain syndrome in genital endometriosis and migraine

Migraine is often concurrent with endometriosis; however, the mechanisms of comorbidity of these conditions are inadequately studied. Pain is considered as the most significant clinical symptom and maladaptive manifestation of both migraine and endometriosis. Studying the relationship between the clinical manifestations of pain syndrome in patients with endometriosis and migraine is important, since it will contribute to the understanding of the mechanisms of comorbidity of these diseases.Objective: to analyze the features of pain syndrome in patients with migraine and genital endometriosis to clarify the neurogenic mechanisms of their comorbid relationship.Patients and methods. A total of 125 patients who had gone to a gynecologist for endometriosis were examined for the presence of migraine. In accordance with the inclusion criteria, 79 patients (mean age, 34.68±7.11 years) with genital endometriosis confirmed by diagnostic laparoscopy participated in the further study. Two age-matched groups were formed: a study group consisted of 38 patients with endometriosis and concomitant migraine; a comparison group included 41 patients with endometriosis without migraine. All the patients underwent clinical neurological examination, questionnaire survey, pelvic ultrasound, assessment of the severity of pelvic pain according to the pelvic pain index, and determination of the level of central sensitization (CS) using the CS Inventory.Results and discussion. 42% out of the 125 patients who had visited their gynecologist for endometriosis suffered from concomitant migraine, which confirms the comorbidity of these diseases. Chronic pelvic pain (CPP), dysmenorrhea, dyspareunia, and dyschesia were more common in patients with endometriosis and migraine; there were more patients with asymptomatic endometriosis in the comparison group. The patients of the two groups did not differ in the presentation of different forms of endometriosis, which favors the leading role of central mechanisms in the pathogenesis of pain syndrome in comorbidity of these diseases.In addition, there was a statistically significant increase in the presentation of CPP and dysmenorrhea in patients with chronic migraine compared to those with episodic migraine and to those without migraine. Significantly higher levels of CS according to CSI and pelvic pain index were found in patients with chronic migraine and endometriosis, which suggests that CS plays a key role in the comorbidity of these diseases.Conclusion. The phenomenon of CS is one of the mechanisms of comorbidity of migraine and endometriosis, contributes to both the worsening of various painful manifestations of endometriosis and the increase in migraine attacks, thereby causing obvious maladaptation in patients. The role of CS in the comorbidity of migraine and endometriosis opens up possibilities for the elaboration of a comprehensive interdisciplinary approach to treating these diseases.

Application of the International Classification of Functioning, Disability and Health (Children and Youth Version) in the Evaluation of Rehabilitation Measures of Patients with Cerebral Palsy

Rehabilitation of children with cerebral palsy (CP) requires a systematic approach and dynamic evaluation of results. The International Classification of Functioning, Disability and Health for Children and Youth (ICF-CY) is used to describe and measure the extent ofhealth disorders in children with CP. This classification allows to unify of identification of an individual profile of functioning of the child taking into account environmental and personal factors, to estimate changes of disorders of health in the course of rehabilitation. However, at the moment there are no clear quantitative criteria that allow using ICF-CY to determine the effectiveness of medical rehabilitation of patients with CP, which is relevant in clinical practice and research. The aim is to develop a criterion for evaluating the effectiveness of medical rehabilitation of children with CP based on the use of ICF-CY. Materials and methods. The study included 29 patients (mean age 5.4±1.05) with various forms of CP, who received medical rehabilitation courses in the hospital and polyclinic for 12 months. All patients, in addition to general physical and clinical neurological examination, were tested before and after rehabilitation courses using specialized questionnaires and scales, as well as evaluated using a brief core set of ICF-CY for children/youth with CP. Groups of patients with and without improvement in the first stage of the study were identified using expert evaluation. The sensitivity and specificity of the proposed criterion for assessing the effectiveness of rehabilitation are calculated at the second stage. The degree of consistency of experts‘ opinions and the developed evaluation criterion is analyzed. Results. The rehabilitation effect was determined on the basis of the dynamics of domain assessments on the components of the ICF-CY “functions”, “activities and participation” 12 months after the beginning of rehabilitation. The criterion of improvement is the positive dynamics of the child’s condition in at least 3 domains with a change in the assessment, at least 1 point. Improvement was achieved in 18 patients with CP 12 months after rehabilitation, according to the expert method. Improvement was observed in 16 patients with CP according to our criterion for evaluating the effectiveness of medical rehabilitation. Improvement was observed in 16 patients with CP according to our criterion for evaluating the effectiveness of medical rehabilitation. The sensitivity of our criterion for assessing the effectiveness of medical rehabilitation of patients with cerebral palsy was 89%, the specificity of 91%, which allows us to recommend the use of this criterion to assess the improvement of the effectiveness of medical rehabilitation of children with CP.

Sepsis-Associated Brain Dysfunction: A Review of Current Literature

Sepsis-associated brain dysfunction (SABD) may be the most common type of encephalopathy in critically ill patients. SABD develops in up to 70% of septic patients and represents the most frequent organ insufficiency associated with sepsis. It presents with a plethora of acute neurological features and may have several serious long-term psychiatric consequences. SABD might cause various pathological changes in the brain through numerous mechanisms. Clinical neurological examination is the basic screening method for SABD, although it may be challenging in subjects receiving with opioids and sedative agents. As electrographic seizures and periodic discharges might be present in 20% of septic patients, screening with electroencephalography (EEG) might be useful. Several imaging techniques have been suggested for non-invasive assessment of structure and function of the brain in SABD patients; however, their usefulness is rather limited. Although several experimental therapies have been postulated, at the moment, no specific treatment exists. Clinicians should focus on preventive measures and optimal management of sepsis. This review discusses epidemiology, clinical presentation, pathology, pathophysiology, diagnosis, management, and prevention of SABD.

Neurological aspects of modern drug addiction

The article presents the results of neurological examination of 95 patients with drug dependence. Neurological symptoms were evaluated comparatively in patients with non-injecting and injecting forms of dependence (n=17 and n=78, respectively). The obtained data of clinical neurological examination were compared with the indicators of magnetic resonance imaging of the brain and neurophysiological assessment of the state of peripheral nerves. A comprehensive analysis of the results of the study indicated that chronic intoxication with injecting drugs leads to the development of more pronounced and polymorphic neurological symptoms. It is also necessary to take into account the key role of intoxication in the formation of a cascade of reactions that change the functions of the nervous system.