The Neurophysiological Testing

Abstract

Neurophysiological testing has an important role in the evaluation of patients affected by neurogenic or dysfunctional bladder. The tests present limits related to age and child compliance. Despite the utility the tests are not used routinely. Electromyography (EMG), somatosensory evoked potential (SSEP), and bulbocavernous reflex represent classic neurophysiological testing. The EMG should be used during cystometry, pressure/flow study, and noninvasive urodynamic study. In pediatric age it is registered in almost all of the patients through surface electrode. The study could be used to detect either detrusor sphincter dyssynergia in neurological patients or dyscoordination in functional patients. The SSEP provides information of the afferent conduction pathway from the peripheral nerves to the spinal cord and sensory cortex in response to electric stimuli at peripheral site. No relevant information is present in the literature regarding pudendal stimulation in pediatric age. The posterior tibial nerve SSEP is widely used, and it is a sensitive indicator of neurophysiological deterioration due to ischemia of the spinal cord in tethered cord. The bulbocavernous reflex (BCR) reflects the functional integrity of sacral sensory and motor nerve fibers and spinal segments, specifically from the second (S2) to the fourth sacral segment (S4). The integrity of this reflex arc can be clinically investigated by means of gentle squeezing the glans penis or the clitoris, evoking responses from the pelvic floor muscles, including the external anal sphincter. BCR has been also evoked through electrical stimulation, but limits related to the compliance of very young children for BCR need to be mentioned.