Industrial and environmental agents
James W. Albers, Stanley Berent in Neurobehavioral Toxicology: Neurological and Neuropsychological Perspectives, 2005
Case presentation (Kajiyama et al., 1993)1A 25-year-old man worked for 2 years at a vinyl chloride resin factory where he was exposed to lead stearate, a stabilizer of resin. Neurological examination revealed atrophy of small hand muscles, especially in the left dorsal interossei (his dominant hand). Sensation was intact, and there was no evidence of a generalized neuropathy.Electrodiagnosis. Nerve conduction studies showed evidence of partial conduction block at the elbow, indicating possible compressive mono-neuropathy related to cubital tunnel syndrome. Within months following chelation therapy, there was progressive recovery of ulnar motor evoked amplitude, conduction velocity, and diminution of the conduction block at elbow.
The eye
Angus Clarke, Alex Murray, Julian Sampson in Harper's Practical Genetic Counselling, 2019
A great variety of types exist, characterised by particular features of fundal appearance, differences in severity and progression, and different responses to various types of electrodiagnostic investigation. It is most unwise for someone who is not an ophthalmologist to venture into diagnosis, but a valuable contribution can be made by documenting the pedigree pattern and carefully searching for any associated syndromic features. This information can then be combined with a specific ophthalmic diagnosis to allow accurate genetic counselling. Two broad groups can be distinguished: Those mainly affecting peripheral vision (e.g. the retinitis pigmentosa group)Those principally involving central vision (e.g. the macular dystrophies)
Activity of Muscles in Non-Myopathic Conditions
A. Bakiya, K. Kamalanand, R. L. J. De Britto in Mechano-Electric Correlations in the Human Physiological System, 2021
Electromyography is the electrodiagnostic technique for recording and analyzing the electrical potentials generated from the neuromuscular system (Ambikapathy & Krishnamurthy, 2018; Ambikapathy et al., 2018; Bakiya & Kamalanand, 2018; Bakiya et al., 2020). The recorded electrical potentials are utilized for the diagnosis of several neuromuscular disorders such as myopathy, multiple sclerosis, peripheral neuropathy and amyotrophic lateral sclerosis (Sadikoglu et al., 2017; Duque et al., 2014), as discussed in the earlier chapters. In general, the EMG recording instruments are designed to record electrical signals in the frequency range of 20 and 450 Hz. However, the frequency range of healthy EMG signals is between 30 and 60 Hz (Duque et al., 2014; Subasi, 2012).
Effect of omalizumab treatment on peripheral nerves in patients with chronic spontaneous urticaria
Published in Cutaneous and Ocular Toxicology, 2021
Erman Altunisik, Esra Inan Dogan
We found only one study in the literature examining the effect of omalizumab treatment on peripheral nerves. In that study, the nerve conduction examinations of patients receiving omalizumab treatment were compared between the pre-treatment period and at three months after treatment. Although there was no pathological finding indicating neuropathic involvement as a result of this comparison, significant changes such as prolonged latencies, reduced amplitudes, and slowed conduction velocity were observed in some nerves after treatment compared to the pre-treatment values, and thus the authors concluded that treatment could affect peripheral nerves8. We used a similar method in our study but evaluated a higher number of motor and sensory peripheral nerves. Similar to the previous research, we detected no pathological finding indicating peripheral nerve involvement in the measured values and there was no significant change in the latency, amplitude and conduction velocity values of the peripheral nerves before and after treatment. Electrodiagnostic measurements can be affected by many factors. These include age, ethnicity, gender, physical conditions of the electrophysiology laboratory, extremity temperature measured, patient height and weight, and the difference in standard values among electrophysiology laboratories21. These factors may have contributed to the emergence of different results despite the use of similar methods with the aforementioned study. Our results led us to consider that omalizumab treatment is not a therapeutic agent that causes pathological effects on peripheral nerves.
Assessment of Saccadic Velocity at the Bedside
Published in Neuro-Ophthalmology, 2020
Melvin L. H. Ling, Dominique Tynan, Claire W. Ruan, Fiona S. Lau, Sascha K. R. Spencer, Ashish Agar, Ian C. Francis
In the laboratory environment, electrodiagnostic techniques are used. However, these require sophisticated neurophysiological equipment, are not readily portable to the bedside, and are often expensive. This compares with emergent clinical decision-making at the bedside, such as in an Emergency Department setting. For instance, a patient with head and orbital injuries may have headache and horizontal diplopia but with a diminishing Glasgow Coma Scale, warranting rapid exclusion of raised intracranial pressure.6 If the abduction of one eye demonstrates slow SV, this presumed 6th nerve palsy strongly suggests the non-localising effect of raised intracranial pressure, and is dealt with accordingly. On the other hand, if the SV of this eye is normal, the clinician can confidently state that the diplopia in this scenario is due to defective abduction from a mechanical aetiology. This could include orbital haemorrhage, or orbital tissue entrapped in an orbital fracture.7 In this environment, portable saccadometers worn on the patient’s head, as used in specific research on Huntington’s disease, are not clinically applicable.8
Carpal tunnel syndrome in patients with and without diabetes mellitus in Upper Egypt: The impact of electrophysiological and ultrasonographical studies
Published in Alexandria Journal of Medicine, 2018
Abeer A. Tony, Effat A.E. Tony, Yasser A.R.M. Selim, Ehab Saad
Electrodiagnostic studies (nerve conduction studies and electromyography) are useful in diagnosis and in differentiation from cervical radiculopathy, diabetes or peripheral neuropathy.2 Nerve conduction studies alone do not provide spatial information regarding the nerve or its attendant abnormalities.12 Ultrasonography (US) has emerged as simple, low cost, rapid accurate and non-invasive imaging method for evaluating the median nerve in the carpal tunnel syndrome.13 Many reports have appeared that agreed that US has high sensitivity and specificity in CTS diagnosis. It can detect the median nerve compression characteristics, provide anatomical images of the median nerve, neighboring structures and space occupying lesions as ganglia neural tumors.2,14 US has been used in clinical evaluation of CTS in diabetic neuropathy.15
Related Knowledge Centers
- Cardiology
- Electroencephalography
- Electromyography
- Electrophysiology
- Evoked Potential
- Neurophysiology
- Medical Diagnosis
- Electrocardiography
- Neurology
- Physical Medicine & Rehabilitation