Actiuation of the external urethral sphincter
central pattern generator by a 5-HT(1A) receptor agonist in rats with chronic spinal cord injury.
DSD occurs when the bladder contracts against a closed pelvic floor (the external urethral sphincter
Pathways from the PMC project to different levels of the spinal cord, rather than to the bladder and external urethral sphincter
(EUS), via multiple peripheral nerves and elicit different reflexes.[sup.7]-[sup.9] Lesions affecting the connection of the PMC and spinal centres culminate in a lack of EUS inhibition at the time of micturition (detrusor external sphincter dysynergia [DESD]), and in the emergence of segmental reflexes responsible for uncontrolled detrusor contractions in response to bladder distension (detrusor overactivity [DO]).
Hyperesthesia was also frequently seen in the external urethral sphincter
along with a hypertonic sphincter and detrusor-sphincter dyssynergia.
Multiple factors may contribute to the risk of SUI following radical prostatectomy including age, preoperative continence status, surgeon experience, education level, concomitant pulmonary disease and need for adjuvant radiation therapy to the prostatic bed.[sup.11,12] The etiologies of SUI after prostatectomy include injury to the nerve, muscle fibers or support structures of the external urethral sphincter
(EUS).[sup.13]-[sup.15] The somatic and autonomic neural innervation of the EUS arise from Onuf's nucleus of the sacral cord.[sup.16]-[sup.18] The post-synaptic autonomic neurons of the EUS have a high density of serotonergic and noradrenergic terminals.
Post-prostatectomy urinary incontinence (PPUI) is usually due to direct damage to the external urethral sphincter
. The incidence of SUI after treatment of prostatic benign disease either using classical trans-urethral resection or laser therapy is estimated to be less than 1% to 3%.[sup.6] The incidence of post-radical prostatectomy urinary incontinence (PPI) is variable depending on the definition, the evaluation tool, and the collection method used.