scholarly journals Sensory Ganglionopathy and the Blink Reflex: Electrophysiological Features

2016 ◽  
Vol 43 (3) ◽  
pp. 385-389 ◽  
Author(s):  
Taimour Alam ◽  
Alexander StJ.E. Barker ◽  
James J.P. Alix ◽  
Marios Hadjivassiliou ◽  
Dasappaiah G. Rao
Keyword(s):  
Dorsal Root ◽  
Clinical Neurophysiology ◽  
Final Analysis ◽  
Blink Reflex ◽  
Nerve Conduction Studies ◽  
Sensory Disturbance ◽  
Sensory Fibre ◽  
Degenerative Disorders ◽  
Electrophysiological Correlate ◽  
Sensory Ganglionopathy

AbstractBackground: Sensory ganglionopathy (SG) is characterised by asymmetrical sensory fibre degeneration, with the primary pathology occurring at the level of the dorsal root ganglion. It is seen in the context of autoimmune, paraneoplastic, and degenerative disorders. There is limited literature examining the electrophysiological correlate of the trigeminal ganglion and associated pathways, the blink reflex (BR), in cases of SG. Previous work has suggested that the BR is preserved in cases of SG associated with paraneoplasia. Methods: The local clinical neurophysiology database was searched for patients diagnosed with SG from peripheral nerve conduction studies in whom the BR was performed. Twenty-six patients were included in the final analysis. Results: Sjögren’s syndrome constituted the most common SG aetiology (8/26), followed by idiopathic cases (7/26) and paraneoplasia (5/26). BR abnormalities were seen in 9 of the 26 patients (34.6%) across all aetiologies. No patients reported sensory disturbance in the distribution of the trigeminal nerve, indicating that the changes noted are subclinical. Three patients showed abnormality of the R1 response; in the remaining six patients, only R2 responses were affected. Conclusions: Subclinical abnormalities of both R1 and R2 can be seen in the context of SG of varying aetiologies, including paraneoplasia. Performing the BR in patients with suspected of having SG may be helpful in providing additional evidence of patchy sensory fibre involvement that is characteristic of the disease.

Application of Clinical Neurophysiology

2016 ◽  
pp. 502-536
Author(s):  
Devon I. Rubin ◽  
Jasper R. Daube
Keyword(s):  
Clinical Application ◽  
Clinical Evaluation ◽  
Nerve Conduction ◽  
Neurological Disease ◽  
Clinical Neurophysiology ◽  
Clinical Findings ◽  
Nerve Conduction Studies ◽  
Specific Diagnosis ◽  
Neurophysiological Assessment ◽  
Selection Of

Clinical neurophysiology testing primarily assesses and characterizes neurological disease. Selection of appropriate studies for the problem of an individual patient requires a careful clinical evaluation to determine possible causes of the patient’s symptoms. The approach to testing can be assisted by deciding which structures are likely to be involved. For example, motor and sensory symptoms are best assessed using the different methods of motor and sensory NCS. Deciding which neurophysiological measures to apply in peripheral disorders is sometimes assisted by applying guideline protocols based on the patient’s clinical findings and what is found during testing. Although a clinical neurophysiological assessment rarely provides evidence for a specific diagnosis, it can provide valuable information about the severity, progression, and prognosis of the disease. This chapter reviews the clinical application of neurophysiological tests, particularly nerve conduction studies and needle EMG, in the assessment of patients with a variety of neuromuscular complaints.

CLINICAL AND ELECTROPHYSIOLOGICAL CHARACTERISTICS OF 103 PATIENTS WITH SENSORY NEURONOPATHY

2015 ◽  
Vol 86 (11) ◽  
pp. e4.51-e4
Author(s):  
Timothy Lavin ◽  
Sarah Al-Bachari ◽  
David Yunus Gosal
Keyword(s):  
Nervous System ◽  
Dorsal Root ◽  
Neuroendocrine Tumours ◽  
Age Of Onset ◽  
Unknown Primary ◽  
Sensory Disturbance ◽  
Nervous System Disorder ◽  
Immunomodulatory Treatment ◽  
Sensory Neuronopathy ◽  
System Disorder

Sensory Neuronopathy (SN) represents a distinct peripheral nervous system disorder associated with degeneration of the Dorsal Root Ganglia. We present our retrospective review of 103 patients with an electro-clinical diagnosis of SN.Average age of onset was 54 yr. Aetiologies included Sjogrens (21%), Probable Inflammatory (16%), Idiopathic (29%), Inherited (20%), Toxic (5%) and paraneoplastic (9%).Of those with inherited SN (n=21); CANVAS syndrome 2/21, mitochrondrial cytopathy 9/21 with 4 confirmed POLG1 mutations, 3/21 presumed HSANIIb, Frederich's Ataxia 1/21 and 6/21 unidentified phenotypes.Clinically, acquired causes commonly presented with pain (62%), asymmetrical/non-length dependent sensory disturbance (91%) as compared to the inherited group who are more likely to present with gait disturbance without prominent sensory symptoms (52%).Of the cohort with presumed inflammatory disease, 29 patients were immunosuppressed with 12 patients responding to a combination of steroids and Mycophenolate. IVIG was not found to be beneficial with no sustained benefit in 7 patients.Paraneoplastic causes (n=9) included Breast (n=2), Neuroendocrine tumours (n=2), Carcinoid (n=2), Bowel (n=1), SCLC (n=1) and unknown primary (n=1) with only 4 Hu positiveConclusionsSensory neuronopathy is clinically and aetiologically pleomorphic. In cases with a suspected inflammatory cause it is worthwhile considering a trial of immunomodulatory treatment.

Clinical neurophysiology

2010 ◽  
pp. 35-44
Author(s):  
George Samandouras
Keyword(s):  
Evoked Potentials ◽  
Nerve Conduction ◽  
Clinical Neurophysiology ◽  
Nerve Conduction Studies

Chapter 1.2 covers nerve conduction studies (NCSs), EEG, and evoked potentials.

scholarly journals Atypical Presentation of Medullary Syndrome in a Young Woman

2020 ◽  
pp. 6-11
Author(s):  
Geetanjali Sharma
Keyword(s):  
Ct Scan ◽  
Nerve Conduction ◽  
Visual Evoked Potential ◽  
Evoked Potential ◽  
Blink Reflex ◽  
Nerve Conduction Studies ◽  
Auditory Evoked Potential ◽  
Ct Guided ◽  
Electrophysiological Tests ◽  
Lateral Medullary Syndrome

Wallenburg syndrome occurs due to damage to lateral segment of the medulla. Medial medullary syndrome occurs due to damage to upper portion of the medulla. I report a case of a 30 years old woman diagnosed with medullary syndrome [both medial & lateral features] in absence of CT scan findings sent to the department of Physiology for electrophysiological tests like nerve conduction studies, blink reflex, brainstem auditory evoked potential (BERA) & visual evoked potential (VEP). She had loss of sensations on the ipsilateral half of face (right), hemisensory loss on contralateral trunk & extremities, headache, contralateral hemiparesis (left), ipsilateral lingual paresis with atrophy, fibrillations with contralateral positive Babinski’s sign. The electrophysiological tests showed decrease in conduction velocity of right facial nerve, left tibial & peroneal nerves with decreased amplitude. The nerve conduction studies of median nerve (both motor & sensory) were normal. In blink reflex, latency of R2 ipsilateral & R2 contralateral of supraorbital nerves were increased on right side. There were increased latencies of waves II, III, IV & V of BERA & increased P100 latencies in VEP. The results of the electrophysiological tests of the patient showed that she had features of both medial & lateral medullary syndrome suggesting a lesion of both upper & middle medulla. The CT scan in this case was normal but conduction of MRI & CT guided angiography of posterior cerebral & vertebral arteries could have further localized the lesion causing this mixed symptomology.

scholarly journals Severe Headache, Paraesthesias, Facial Diplegia and Pleocytosis: A Misleading Presentation of Guillain-Barré Syndrome

2021 ◽  
Author(s):  
Mohamed Reda Belkhribchia ◽  
Abderrahim Chekabab ◽  
Yahya Naji ◽  
Latifa Hadrane ◽  
Soufiane Hassar ◽  
...  
Keyword(s):  
Clinical Manifestations ◽  
Severe Headache ◽  
Nerve Conduction Studies ◽  
Guillain Barre Syndrome ◽  
Sensory Disturbance ◽  
Limb Weakness ◽  
Motor Weakness ◽  
Facial Diplegia ◽  
Guillain Barré Syndrome ◽  
Guillain Barré

Guillain-Barré syndrome (GBS) is an acute inflammatory polyradiculoneuropathy. Progressive limb weakness, diminished/absent reflexes, sensory disturbance, and variable autonomic dysfunction are its core clinical manifestations. Bifacial weakness with paraesthesias (BFP) is a rare regional variant of GBS and is characterized by simultaneous facial diplegia, distal paraesthesias and minimal or no motor weakness. The association of headache with classic GBS has been rarely reported in the literature, and has not yet been described in the BFP variant. Here we report a misleading case of BFP variant associated with severe headache and mild pleocytosis. The repetition of nerve conduction studies (NCS) was extremely beneficial in this confusing case.

scholarly journals The Potentials Recorded Around the Spinal Cord

2013 ◽  
Vol 21 (3) ◽  
pp. 449-454
Author(s):  
Lydia Maria Pereira Giuliano ◽  
Karlo Faria Nunes ◽  
Gilberto Mastrocola Manzano
Keyword(s):  
Spinal Cord ◽  
Electric Potential ◽  
Dorsal Root ◽  
Historical Perspective ◽  
Clinical Neurophysiology ◽  
Potential Fields ◽  
Primary Afferent Depolarization ◽  
Dorsal Root Reflex ◽  
Root Potential ◽  
Over Time

Introduction. Clinical Neurophysiology is strongly based on the interpretation of electric potential fields. Such interpretations may sometimes create different conceptual objects that over time end up as different sides of the same phenomenon. An instructive example is represented by the potential fields recorded around the spinal cord viewed from a historical perspective. Method. A brief historical ac­count is given of the potentials recorded around the spinal cord. Re­sults. Dorsal root reflex, dorsal root potential, cord dorsum potential and primary afferent depolarization are described. Conclusion. all these potentials are mainly different aspects of the same generator - the segmental spinal cord activities - secondary to the recordings by different leads.

scholarly journals Clinical Neurophysiology

2009 ◽  
Author(s):  
Jasper R. Daube ◽  
Devon I. Rubin
Keyword(s):  
Evoked Potentials ◽  
Nerve Conduction ◽  
Clinical Neurophysiology ◽  
Nerve Conduction Studies ◽  
Electrophysiological Testing ◽  
Methods And Techniques ◽  
Disease Entities

This resource provides a didactic, yet accessible, presentation of electrophysiology that describes the analysis of electrophysiological waveforms, the various methods and techniques of electrophysiological testing, and recommendations of symptom complexes and disease entities using electroencephalography, evoked potentials, and nerve conduction studies.

Membrane-associated microtubular areays induced in proximal myelinated processes of dorsal root ganglia by large doses of vitamin B6

1986 ◽  
Vol 44 ◽  
pp. 368-369
Author(s):  
V.J. Montpetit ◽  
S. Dancea ◽  
L. Tryphonas ◽  
D.F. Clapin
Keyword(s):  
Animal Model ◽  
Endoplasmic Reticulum ◽  
Dorsal Root Ganglia ◽  
Rough Endoplasmic Reticulum ◽  
Dorsal Root ◽  
Vitamin B6 ◽  
Morphological Changes ◽  
Model System ◽  
Sensory Nerves ◽  
Peripheral Sensory

Very large doses of pyridoxine (vitamin B6) are neurotoxic in humans, selectively affecting the peripheral sensory nerves. We have undertaken a study of the morphological and biochemical aspects of pyridoxine neurotoxicity in an animal model system. Early morphological changes in dorsal root ganglia (DRG) associated with pyridoxine megadoses include proliferation of neurofilaments, ribosomes, rough endoplasmic reticulum, and Golgi complexes. We present in this report evidence of the formation of unique aggregates of microtubules and membranes in the proximal processes of DRG which are induced by high levels of pyridoxine.

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