China
Africa
Explore chapters and articles related to this topic
Cellular and Extracellular Abnormalities
Published in Maher Kurdi, Neuromuscular Pathology Made Easy, 2021
Recognition of intracellular and extracellular abnormalities is an important step in interpreting nerve biopsies. These abnormalities can occur in any layer of nerve fascicle. In order to identify all cellular-related structures, pathologists should start examining the paraffin sections followed by toluidine sections. The paraffin sections highlight these abnormalities morphologically better than epoxy-embedded sections. Several types of cellular and extracellular abnormalities affecting peripheral nerves are summarized in Table 28.1 and Table 28.2.
Introduction: Background Material
Published in Nassir H. Sabah, Neuromuscular Fundamentals, 2020
A peripheral nerve or simply a nerve is a cable-like bundle of nerve fibers in the peripheral nervous system. A fiber tract, or a tract, is a bundle of nerve fibers in the central nervous system. A nerve fascicle, or fascicle, is a small fiber tract whose nerve fibers have similar origin, termination, and function. A bundle of one or more nerve fascicles is a funiculus.
Regulation of Sympathetic Nerve Activity in Humans: New Concepts Regarding Autonomic Adjustments to Exercise and Neurohumoral Excitation in Heart Failure
Published in Irving H. Zucker, Joseph P. Gilmore, Reflex Control of the Circulation, 2020
David W. Ferguson, Allyn L. Mark
The nerve recordings are obtained with tungsten microelectrodes inserted percutaneously and advanced into either a muscle or cutaneous fascicle of the nerve with a reference electrode inserted subcutaneously several centimeters from the recording electrode. The recording electrode is advanced into the nerve fascicle by using weak electrical stimulation so that when the electrode enters a nerve fascicle to muscle it elicits involuntary twitching. When it enters a nerve fascicle to skin it elicits paresthesias.
Shoulder abduction reconstruction for C5–7 avulsion brachial plexus injury by dual nerve transfers: spinal accessory to suprascapular nerve and partial median or ulnar to axillary nerve
Published in Journal of Plastic Surgery and Hand Surgery, 2022
Gavrielle Hui-Ying Kang, Fok-Chuan Yong
A complication of reduced thumb and index finger flexion power (to M4) was noted in one patient. Songcharoen et al. [20] reported a similar complication in one of the 15 patients who had partial median nerve transfer to the biceps branch of musculocutaneous nerve. This may be due to the funicular and plexiform pattern of the nerve fasciculations of the peripheral nerves at the arm level, before they split to form collateral branches proximal or distal to the elbow [21]. Thus, a nerve fibre destined for the thumb and index finger flexor may have entered the fascicle for the wrist flexor or FDS proximally and exited at some distance distally. This nerve fibre could have been divided during mobilization of the donor fascicle for a distance sufficient for transfer to the recipient nerve stump. Also, we may have accepted a suboptimal motor response during the nerve stimulation process of the different nerve fascicles in confirming the important motor function to be spared. We recommend a more discerning approach during intra-operative nerve fascicle stimulation to isolate and choose the donor nerve fascicles.
Isolated Compressive Sixth Nerve Palsy due to Multiple Intracranial Cavernomas
Published in Neuro-Ophthalmology, 2021
Janardhanan Jinisha, Pushkaran Muralitharan, Virna M. Shah
Although cranial nerve palsies due to cavernomas have already been reported in literature earlier,8 our case presented with an isolated sixth nerve palsy, which was due to the cavernoma present in the pons causing compression of the nerve fascicle, as there were no signs of any fresh haemorrhage seen. Since our patient improved, the compression could also have been because of a cerebral micro-bleed, which is impossible to differentiate from tiny cavernomas on MRI.2 Sixth nerve nucleus lesions give rise to ipsilateral horizontal gaze palsies;9 however, this was absent in our case. Also, since the seventh nerve wraps around the sixth nerve nucleus, the ipsilateral seventh nerve also should be involved, which was also unaffected in our case. Isolated sixth nerve palsy from pontine cavernous haemangioma has been reported but, unlike our case, their case had a solitary lesion with a fresh haemorrhage.10
Unaltered neurocardiovascular reactions to mental stress after renal sympathetic denervation
Published in Clinical and Experimental Hypertension, 2020
Sebastian Völz, Linda C. Lundblad, Bert Andersson, Jonas Multing, Bengt Rundqvist, Mikael Elam
Subjects were resting in a chair (upper body approximately 125 degrees and lower legs approximately 30 degrees from the horizontal plane). All subjects underwent a passive rest period of 15 min followed by 3 min of forced arithmetics. Multi-unit MSNA was assessed with the microneurography technique with an insulated tungsten microelectrode (impedance 1 or 5 MΩ, FHC, Maine, USA), with a tip diameter of a few micrometers, inserted into the left common peroneal nerve posterior to the fibular head. A nearby subdermal microelectrode served as the reference electrode and a surface Ag/AgCl electrode on the knee served as a ground electrode. When a muscle nerve fascicle had been identified by electrical stimuli delivered through the microelectrode, small electrode adjustments were made until a site with sympathetic impulses with good signal-to-noise ratio could be recorded. The nerve signal was amplified (gain 40000, filtered (bandpass) 0.7–2 kHz) using a low noise, electrically isolated amplifier (Neuro Amp EX front-end and head stage, ADInstruments, Australia) and the filtered and integrated nerve signals were sampled (200 Hz) and stored with other signals on a personal computer, using a DT9804 AD converter (Data Translation Inc, MA, USA) with locally produced software. To induce mental stress a 3 min forced arithmetics test was used.