Joao Leote1, Pedro Pereira2, Christopher Cabib3, Federica Cipullo3, Josep Valls-Sole3. 1. Neurosurgery Department, Hospital Garcia de Orta, Almada, Portugal. 2. Neurology Department, Hospital Garcia de Orta, Almada, Portugal. 3. EMG Unit, Neurology Department, Hospital Clinic, University of Barcelona, Barcelona, Spain.
Abstract
INTRODUCTION: Low-intensity electrical stimuli of digital nerves may generate a double peak potential (DPp), composed of a cathodal (caAP) and an anodal (anAP) potential in orthodromic recordings. METHODS: We studied the effects on caAP and anAP of stimuli of variable intensity, duration, and frequency. We also applied a conditioning stimulus to study potential differences in recovery time. RESULTS: The anAP was obtained in 33 of 40 healthy subjects (82.5%) and 4 of 20 patients with various types of sensory neuropathies (20%). Changes in stimulus duration and intensity had reciprocal effects on the amplitude of the anAP and the caAP. There were significant differences in recovery time between caAP and anAP after a conditioning stimulus. CONCLUSION: The caAP and anAP are 2 interdependent waveforms generated by different effects of the same stimulus over axons at the verge of depolarization. Muscle Nerve 53: 897-905, 2016.
INTRODUCTION: Low-intensity electrical stimuli of digital nerves may generate a double peak potential (DPp), composed of a cathodal (caAP) and an anodal (anAP) potential in orthodromic recordings. METHODS: We studied the effects on caAP and anAP of stimuli of variable intensity, duration, and frequency. We also applied a conditioning stimulus to study potential differences in recovery time. RESULTS: The anAP was obtained in 33 of 40 healthy subjects (82.5%) and 4 of 20 patients with various types of sensory neuropathies (20%). Changes in stimulus duration and intensity had reciprocal effects on the amplitude of the anAP and the caAP. There were significant differences in recovery time between caAP and anAP after a conditioning stimulus. CONCLUSION: The caAP and anAP are 2 interdependent waveforms generated by different effects of the same stimulus over axons at the verge of depolarization. Muscle Nerve 53: 897-905, 2016.
Authors: Martin Sommer; Matteo Ciocca; Raffaella Chieffo; Paul Hammond; Andreas Neef; Walter Paulus; John C Rothwell; Ricci Hannah Journal: Brain Stimul Date: 2018-01-05 Impact factor: 8.955