Nicolet viking select

For neurophysiologic study, auditory brainstem responses (ABRs), distortion product otoacoustic emission (DPOAE), and nerve conduction of median nerves were recorded in CMT1A patients. The equipment used to record brainstem auditory evoked potentials was Nicolet Viking Select (Natus Medical Inc., USA). Click stimuli at 80 dB nHL were transmitted via inserted earphone. Absolute latency (stimulus to peak) of each peak (I, III, and V) and inter-peak latencies (I–III, I–V, and III–V) were measured. DPOAE was recorded using an ILOV6 OAE analyzer (Otodynamics Ltd., USA). Primary signals f1 and f2, with f2/f1 = 1.22, generated with test frequencies ranging from 1001 Hz to 6006 Hz with a frequency resolution of one DPOAE per octave was used. Two levels were chosen: L1 = 65 dB SPL, L2 = 55 dB SPL. Response parameters to consider DPOAE as present included DP amplitude and SNR. A peak at 2f1-f2 in the spectrum was accepted as a DPOAE if it was 3 dB above the noise floor. Nerve conduction studies were performed by placing surface electrodes on median nerves. Motor nerve conduction velocities (MNCVs) for median nerves were determined by stimulating at the elbow and wrist while recording compound muscle action potentials (CMAPs) over the abductor pollicis brevis muscle.

Electrodiagnostic studies were performed under general inhalation anesthetic protocol by a board‐certified neurologist or a neurology resident in training supervised by a board‐certified neurologist using similar devices (Nicolet Viking Select or Nicolet Viking Quest; Natus Medical Incorporated, Pleasanton, California, USA) on the left side of the cats.
Electrodiagnostic data were interpreted and compared with retrospectively reviewed results obtained in the intact limb of cats with traumatic plexus injury or non‐neurologic lameness of the contralateral limb from 2010 to 2022.

Electroencephalography (EEG), auditory evoked potentials (AEP), visual evoked potentials (VEP), somatosensory evoked potentials (SEP) of the median nerve were recorded usually within the first two weeks after admission. EEG was done using the international 10/20 system (Neurofax EEG 9000, Nihon Kohden Europe, Rosbach, Germany). Surface electrodes were used for evoked potentials (Nicolet Viking Select, Natus Medical, Middleton, WI, USA). VEPs were recorded with flashing light-emitting diodes (flash VEP, stimulation frequency 1.3Hz). Latencies and amplitudes of wave I-III were examined according to the guidelines of the American Clinical Neurophysiology Society [34 ]. Further, AEP latencies I-V and N20/P25 latencies and amplitudes of median nerve SEPs were analyzed. Neurophysiological examinations were performed by an experienced team of only four paramedics working in this field for many years.