Background: 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.

Objectives: 1) Assess which electrodiagnostic studies Canadian clinicians use to aid in the diagnosis of carpal tunnel syndrome (CTS). 2) Assess whether Canadian clinicians follow the American Association of Neuromuscular & Electrodiagnostic Medicine/American Academy of Neurology/American Academy of Physical Medicine and Rehabilitation Practice Parameter for Electrodiagnostic Studies in CTS. 3) Assess how Canadian clinicians manage CTS once a diagnosis has been established. Methods: In this prospective observational study, an electronic survey was sent to all members of the Canadian Neuromuscular Group (CNMG) and the Canadian Association of Physical Medicine and Rehabilitation (CAPM&R) Neuromuscular Special Interest Group. Questions addressed which electrodiagnostic tests were being routinely used for the diagnosis of carpal tunnel syndrome. Management recommendations for CTS was also explored. Results: Of the 70 individuals who completed the survey, fourteen different nerve conduction study techniques were reported. Overall, 36/70 (51%) of participants followed the AANEM/AAN/AAPM&R Practice Parameter. The standard followed by the fewest of our respondents with 64% compliance (45/70) was the use of a standard distance of 13 to 14 cm with respect to the median sensory nerve conduction study. Regarding management, 99% would recommend splinting in the case of mild CTS. In moderate CTS, splinting was recommended by 91% of clinicians and 68% would also consider referral for surgery. In severe CTS, most recommended surgery (93%). Conclusions: There is considerable variability in terms of which electrodiagnostic tests Canadian clinicians perform for CTS. Canadian clinicians are encouraged to adhere to the AANEM/AAN/AAPM&R Practice Parameter for Electrodiagnostic Studies in CTS.