Spinal Cord Disease
Philip B. Gorelick, Fernando D. Testai, Graeme J. Hankey, Joanna M. Wardlaw in Hankey's Clinical Neurology, 2020
Genetic testing, often in the form of a panel, is required to arrive at a precise genetic diagnosis. Other workup focuses on clarifying the phenotype and ruling out disease mimics: MRI of the brain and spinal cord.Serum vitamin B12, copper, folate, vitamin E.Syphilis testing, HTLV-1 and HIV antibodies.Plasma long-chain fatty acid analysis.Electrophysiology: Nerve conduction studies: normal unless a complicated form of HSP with associated neuropathy.Somatosensory evoked potential, after stimulation of peripheral nerves in the lower limbs, shows conduction delay in dorsal column fibers.
Brain death and ethical issues: Death by neurological criteria
Hemanshu Prabhakar, Charu Mahajan, Indu Kapoor in Essentials of Geriatric Neuroanesthesia, 2019
The most commonly used electrophysiologic ancillary study is EEG. A minimum of eight scalp electrodes should be used and interelectrode impedance should be 100–10,000 Ohms. Electrodes should be spaced at least 10 cm from each other. EEG must show absence of electrical activity (isoelectric recording) at a sensitivity of 2 microvolts for 30 minutes for the determination of brain death. There should be no reactivity to external stimuli (4,26). There are significant limitations to this test, causing it to fall out of favor. EEG is very susceptible to false positives. EEG can be affected by medications or sedation, hypothermia, toxic or metabolic derangements, and external artifacts or interference. In addition, large case series have shown that up to 3.5% of patients who are clinically brain dead can maintain rudimentary EEG activity for several hours after clinical diagnosis has been made (27). Finally, EEG does not assess brainstem function, and thus, if used, should only be used in combination with evoked potentials (see the following section, “Somatosensory evoked potentials”).
The electrophysiology laboratory
John Edward Boland, David W. M. Muller in Interventional Cardiology and Cardiac Catheterisation, 2019
Electrophysiology (EP) is the science of recording, analysis, and interpretation of the electrocardiogram (ECG) via surface and intracardiac electrodes. Patients with heart rhythm disturbances are studied and treated in the EP laboratory. Invasive EP involves recording spontaneous and pacing-induced intracardiac electrical activation patterns and their study in a controlled environment. If an arrhythmia is suspected, diagnostic tests including measurement of conduction intervals in response to pacing, and programmed electrical stimulation of the heart may be performed to determine the source of the arrhythmia. Therapeutic procedures performed in the EP laboratory include transcatheter radiofrequency ablations, implantations of permanent pacemakers and defibrillators, overdrive pacing and electrical cardioversions. This chapter outlines the basic functions of the EP laboratory and describes equipment used, types of procedures performed, and the reasons for doing so. For the beginner, this is a concise and simple introduction into a complex and fast-growing branch of cardiology.
Impact of biomimetic electrical stimulation combined with Femoston on pregnancy rate and endometrium characteristics in infertility patients with thin endometrium: a prospective observational study
Published in Gynecological Endocrinology, 2023
Yilinuer Shabiti, Shaadaiti Wufuer, Remila Tuohuti, Tan Yun, Jing Lu
Bioelectricity is a kind of physicochemical change in life activities, a basic feature of living organisms, and a manifestation of normal physiological activities. Electrophysiology has developed rapidly in different disciplines in recent years. Electrophysiology research can help understand the functional status of the body. It can be used to diagnose diseases (e.g. electrocardiogram), but it can also help intervene for function regulation intervention, and it is possible to use it for disease prevention and treatment clinically. Biomimetic electrical stimulation acts on pelvic floor muscles and nerves through low-frequency currents, promotes lymphatic and blood circulation by stimulating the nerve-muscle-visceral reflex axis, improves endometrial blood flow and tissue nutrition, accelerates the healing of damaged tissue, and promotes endometrial repair [23,24]. A study enrolled 41 patients with a thin endometrium (≤ 7 mm) and undergoing assisted reproductive technology; they received intermittent vaginal electrical stimulation for 20–30 min on treatment days. The results showed that pelvic floor nerve stimulation significantly increased uterine endometrial thickness in patients with a thin endometrium [14]. By stimulating the repeated contraction and relaxation of uterine smooth muscle, the blood supply to the entire endometrial and subendometrial region can be increased, resulting in better nourishment of the endometrial tissues [14].
The Effect of Walking in High Heels on the Activation and Deactivation of Upper Trunk Muscles
Published in Journal of Motor Behavior, 2023
Jakub Čuj, Miloslav Gajdoš, Pavol Nechvátal, Cyril Grus, Michal Macej, Lucia Demjanovič Kendrová
Muscle electrical activity was recorded with a portable electromyograph BIOMONITOR ME6000 (Mega Electronics Ltd., Finland). The input circuits achieve a consensual interference suppression factor of typically 110 dB. The sampling rate for digitization was set to 1 kHz in each channel, with a converter resolution of 14-bits. We set the sampling frequency of the instrument to 1000 Hz per channel. The motor units and their electrical potential was sensed with self-adhesive approved 2.7 cm diameter Ag/AgCl MEDICO LEAD-LOK hydrogel electrodes (Medico Electrodes Int., India, ISO 13485:2003). Electrodes for EMG analysis were localized on the respondents’ bodies based on the SENIAM (Surface EMG for the Noninvasive Assessment of Muscles) and ISEK (The International Society of Electrophysiology and Kinesiology) standards, which determine the principles of electromyographic measurement. The mentioned standards describe the localization of the electrodes as the position of two bipolar sites overlapping the muscle with respect to the line of two anatomical points in the direction of the muscle fibers, at 2 cm from each other. The location of the electrodes was always in the direction of the muscle fibers so that their junction was at the point of greatest muscle tension during the selected movement. In this way, the most suitable places for sticking the electrodes were determined on the muscles selected for measurement, which were applied by a trained physiotherapist with at least 5 years of experience in the field. We proceeded in the same way for all respondents.
Effects of cardiac growth on electrical dyssynchrony in the single ventricle patient
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2023
O. Z. Tikenoğulları, M. Peirlinck, H. Chubb, A. M. Dubin, E. Kuhl, A. L. Marsden
In adult patients with normal anatomy and ventricular dyssynchrony, cardiac resynchronization therapy is a well-established treatment modality. However, the use of cardiac resynchronization therapy in pediatric and congenital heart disease patients is less established (Joyce et al. 2020). For single ventricle patients specifically, no study has been able to demonstrate a significant improvement in survival (Chubb et al. 2022). Furthermore, the risk of transplantation or death has been shown to be up to four times higher in paced versus non-paced HLHS patient cohorts (Chubb et al. 2022). This substantially raised hazard ratio is thought to be correlated with the discoordinated contraction of the paced single ventricle. However, these dyssynchrony mechanisms in the single ventricle patient populations remain poorly understood (Motonaga et al. 2012). Therefore, an improved understanding of the electrophysiology of the single ventricle heart is urgently required to improve ventricular pacing and cardiac resynchronization therapies in this high risk patient population.
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