MyMedR

Displaying all 4 publications

Abstract:

Sort:

Sensory nerves are frequently involved in the spectrum of fisher syndrome

Shahrizaila N, Goh KJ, Kokubun N, Tan AH, Tan CY, Yuki N

Muscle Nerve, 2014 Apr;49(4):558-63.
PMID: 23893512 DOI: 10.1002/mus.23973

Differing patterns of neurophysiological abnormalities have been reported in patients with Fisher syndrome. Fisher syndrome is rare, and few series have incorporated prospective serial studies to define the natural history of nerve conduction studies in Guillain-Barré syndrome.

Matched MeSH terms: Sensory Receptor Cells/physiology*
Serial nerve conduction studies provide insight into the pathophysiology of Guillain-Barré and Fisher syndromes

Shahrizaila N, Goh KJ, Kokubun N, Abdullah S, Yuki N

J Neurol Sci, 2011 Oct 15;309(1-2):26-30.
PMID: 21849173 DOI: 10.1016/j.jns.2011.07.042

The electrodiagnosis of Guillain-Barré syndrome (GBS) can be broadly divided into acute inflammatory demyelinating polyneuropathy (AIDP) and acute motor axonal neuropathy (AMAN). Fisher syndrome (FS) is a variant of GBS, although the underlying neuropathy of FS has yet to be established. Serial nerve conduction studies (NCS) can provide further insight into the likely pathophysiology by further subtyping of GBS and FS. We present a patient with an initial diagnosis of AIDP in whom repeated NCS revealed the AMAN variant. This led us to investigate serial NCS in five patients with GBS, FS and FS/GBS overlap presenting over a period of a year. Three patients with AIDP showed a gradual increase in distal motor latencies during the acute phase of illness. NCS of two patients with FS and FS/GBS overlap showed no demyelinating features suggesting underlying axonal neuropathy in this group of patients. The importance of serial NCS in establishing the underlying pattern of neuropathy in GBS and FS is further emphasized in this study. Larger studies incorporating serial NCS are required to confirm the observations seen in our case series especially when pathological studies are often not justified in this group of patients.

Matched MeSH terms: Sensory Receptor Cells/physiology
Aesthetic refinements in second toe-to-thumb transfer surgery

Zhao J, Tien HY, Abdullah S, Zhang Z

Plast Reconstr Surg, 2010 Dec;126(6):2052-2059.
PMID: 21124145 DOI: 10.1097/PRS.0b013e3181f44994

BACKGROUND: Second toe-to-thumb transfer is a good alternative to using the great toe for reconstruction of the thumb. It achieves excellent function and reduces morbidity to the donor foot. However, cosmesis is often poor. The second toe has three unattractive features, a narrow "neck," a bulbous tip, and a short nail.
METHODS: The authors describe a modified second toe transfer that addresses cosmesis in six patients. These include (1) harvesting a flap from the adjacent side of the great toe and insetting it into the volar aspect of the second toe to give more bulk, (2) making skin excisions on each side of the tip to reduce the bulbous appearance, and (3) excising the eponychium to produce apparent lengthening of the nail.
RESULTS: The mean follow-up period was 18 months (range, 6 to 36 months). The procedure resulted in good function and improved cosmesis in all six cases. Part of the great toe flap was lost in one case. The mean two-point discrimination in the transferred toes was 10.1 mm, with protective sensation present in the flaps. The range of motion of the transferred toe was 14 to 38 degrees at the metatarsophalangeal joint, 16 to 55 degrees at the proximal interphalangeal joints, and 20 to 36 degrees in the distal interphalangeal joints. All patients except one were happy with the appearance of the transferred toe.
CONCLUSION: This novel approach will allow patients to take advantage of the lower morbidity to the donor site afforded by second toe-to-thumb transfer and provide the patients with a more aesthetic appearance of the new thumb.

Matched MeSH terms: Sensory Receptor Cells/physiology
Cardiovascular autonomic effects of transcutaneous auricular nerve stimulation via the tragus in the rat involve spinal cervical sensory afferent pathways

Mahadi KM, Lall VK, Deuchars SA, Deuchars J

Brain Stimul, 2019 05 06;12(5):1151-1158.
PMID: 31129152 DOI: 10.1016/j.brs.2019.05.002

BACKGROUND: Electrical stimulation on select areas of the external auricular dermatome influences the autonomic nervous system. It has been postulated that activation of the Auricular Branch of the Vagus Nerve (ABVN) mediates such autonomic changes. However, the underlying neural pathways mediating these effects are unknown and, further, our understanding of the anatomical distribution of the ABVN in the auricle has now been questioned.
OBJECTIVE: To investigate the effects of electrical stimulation of the tragus on autonomic outputs in the rat and probe the underlying neural pathways.
METHODS: Central neuronal projections from nerves innervating the external auricle were investigated by injections of the transganglionic tracer cholera toxin B chain (CTB) into the right tragus of Wistar rats. Physiological recordings of heart rate, perfusion pressure, respiratory rate and sympathetic nerve activity were made in an anaesthetic free Working Heart Brainstem Preparation (WHBP) of the rat and changes in response to electrical stimulation of the tragus analysed.
RESULTS: Neuronal tracing from the tragus revealed that the densest CTB labelling was within laminae III-IV of the dorsal horn of the upper cervical spinal cord, ipsilateral to the injection sites. In the medulla oblongata, CTB labelled afferents were observed in the paratrigeminal nucleus, spinal trigeminal tract and cuneate nucleus. Surprisingly, only sparse labelling was observed in the vagal afferent termination site, the nucleus tractus solitarius. Recordings made from rats at night time revealed more robust sympathetic activity in comparison to day time rats, thus subsequent experiments were conducted in rats at night time. Electrical stimulation was delivered across the tragus for 5 min. Direct recording from the sympathetic chain revealed a central sympathoinhibition by up to 36% following tragus stimulation. Sympathoinhibition remained following sectioning of the cervical vagus nerve ipsilateral to the stimulation site, but was attenuated by sectioning of the upper cervical afferent nerve roots.
CONCLUSIONS: Inhibition of the sympathetic nervous system activity upon electrical stimulation of the tragus in the rat is mediated at least in part through sensory afferent projections to the upper cervical spinal cord. This challenges the notion that tragal stimulation is mediated by the auricular branch of the vagus nerve and suggests that alternative mechanisms may be involved.

Matched MeSH terms: Sensory Receptor Cells/physiology*