Perineal Contraction Research Articles

Urethral pressure response to cough and voluntary perineal contraction in men without previous pelvic surgery.

The aim of this study was to analyze the urethral pressure responses to cough in men to better characterize the neurogenic mechanisms of male urethral function. A prospective study was carried out on 41 men referred for urodynamic assessment. Urethral pressure profiles at rest and during coughing, and urethral pressure response to voluntary perineal contraction were recorded and analyzed in relation to the neurological status of the patients. Voluntary perineal contraction resulted in a urethral pressure increase (delta pU) of approximately 150 cm H2O in neurologically normal patients. Delta pU could be reduced to any degree in patients with either central or peripheral neurological lesions. Urethral pressure response to cough could be easily classified into two main patterns. Pattern I was characterized by a marked increase in urethral closure pressure during the cough (ratio of urethral to rectal pressure increase: 248 +/- 106%), occurring at the distal part of the posterior urethra. All the neurologically normal patients and the majority of those with upper motoneuron lesions had a pattern I response. Pattern II was defined by the absence of any significant increase in urethral closure pressure at any site of the posterior urethra and was observed in 80% of the patients with signs of lower motoneuron lesions. The pattern of the response to cough was significantly related to the neurological status of the patients (P < 0.001). It was dissociated from the response to voluntary contraction, as would be expected for a reflex versus a voluntary response in neurological patients.

Short-term effect of pudendal nerve electrical stimulation on detrusor hyperreflexia in spinal cord injury patients: importance of current strength

Twenty patients with chronic suprasacral spinal cord injury presenting with detrusor hyperreflexia were examined. In a preliminary study in ten patients we investigated the reproducibility of bladder capacity through the repetition of three cystometries. The effect of electrical stimulation (ES) on detrusor hyperreflexia was then investigated in ten patients during three consecutive cystometries, the first one without ES (baseline) and the other two with continuous ES of the dorsal penile or clitoris nerve via surface electrodes. Parameters of stimulation were 5 Hz frequency, 0.50 msec pulse duration, and stimulation strength of 1 and 2 times the bulbocavernosus reflex threshold. No significant differences in bladder capacity were found between the three consecutive cystometries without ES (respectively 97.0 ml, 101.5 ml and 105.6 ml). A current at the bulbocavernosus threshold (mean 24.4 mA) failed to induce a significant increase in bladder capacity compared to baseline (173.0 ml vs 155.5 ml, P = 0.17) whereas a current of twice the bulbocavernosus threshold (mean 48.9 mA) was highly significant (318.5 ml vs 155.5 ml, P < 0.007). ES of twice the threshold resulted in perineal contraction in all of the patients, the threshold ES never did. Our results emphasise the decisive roles of perineal contraction and of current strength for achieving short-term bladder inhibition in spinal cord injury patients. The carry-over effect may also be dependent on the current strength. If so, maximal pudendal ES could represent an alternative procedure in the treatment of detrusor hyperreflexia in these patients.

Management of Incontinent SCI Patients with Penile Stimulation: Preliminary Results

We investigated dorsal penile stimulation for control of incontinence in nine spinal cord impaired (SCI) patients, using a battery-powered home-use stimulator connected to surface electrodes (Unipatch). The efficacy of the penile stimulation was assessed by urodynamic evaluation (NL-2, LifeTech) and surface electrodes (Unipatch); baseline and repeat cystometries (CMG) with and without stimulation were done. Stimulation for home use was begun at threshold parameters for inducing perineal contractions and, after two weeks, was adjusted based upon results. Two subjects successfully completed the study and became continent. One of these patient's CMG demonstrated hyperreflexia and his volume increased from 110 ml to 150 ml after the stimulation protocol. The most effective stimulating parameters were 5 pps, 250 microsec, pulse width and 40 ma current. The other patient also had a hyperreflexic bladder and improved on the protocol. The remaining seven patients did not complete the study for several reasons. Three patients had CMG's that demonstrated areflexia. Stimulation did not alter their bladder function and they dropped out of the program. Three other subjects withdrew because of bothersome sensations even at subthreshold levels and they complained that the technique was cumbersome. Finally, one patient with significant hyperreflexia and incontinence withdrew after trying unsuccessfully and diligently for 10 days. Our encouraging results in two patients with hyperreflexic bladders and decreased sensation suggest that this modality may be effective in this patient group.

Normal anorectum: dynamic MR imaging anatomy.

In this study, the anatomy of the anorectum in relation to the surrounding structures and the anorectal angle were analyzed with magnetic resonance (MR) imaging at rest, during perineal contraction, and during straining in 10 asymptomatic subjects. The intra- and inter-observer and intra- and interpatient variations in the measurements of the anorectal angle, position of the anorectal junction, and position of the plica of Kohlrausch in the rectum were established at rest, during perineal contraction, and during straining. The values for the anorectal angle and position of the anorectal junction obtained with MR imaging were compared with standard radiography defecography findings. It was shown that MR imaging has the potential for measuring these parameters in a more precise and more patient-friendly way than defecography. Unlike dynamic defecography, MR imaging is able to depict the mobility of the posterior rectal wall. A descent of over 20 mm from rest to straining should be considered pathologic. This finding might play a role in patient selection for operation.