Initiation of erection and semen release by rectal probe electrostimulation (RPE)

Effects of transanal pelvic plexus stimulation on penile erection: clinical implications

OBJECTIVE

To determine the ability of transanal pelvic plexus stimulation (TPPS) in inducing penile tumescence in patients with non-neurogenic erectile dysfunction (ED) and to compare the erection degree with papaverine-induced erection.

PATIENTS AND METHODS

The cavernous electrical activity (CEA) in 21 men with non-neurogenic erectile dysfunction was measured during TPPS by electromyography of corpus cavernosum and the erection degree of penis (flaccid, semi-rigid, rigid) was noted. The stimulation amplitude was increased from 20 to 100 mA. All patients also underwent intracavernous papaverine injection and further CEA recordings were obtained.

RESULTS

Twelve and nine patients were diagnosed with vasculogenic (VED) and non-vasculogenic ED (NVED), respectively. TPSS led to a penile erectile response in 12 patients (57%), whereas papaverine injection caused erection in 16 (76.2%) patients. The mean baseline CEA (16.9 +/- 9.1 mV) did not change with TPPS, but papaverine significantly decreased the mean CEA to 12.3 +/- 4.9 mV (P < 0.001). CEA recordings of 16 (76.2%) patients revealed a significant decrease after papaverine injection, however seven (33.3%) patients showed significant CEA decrease in response to TPPS. Both TPPS and papaverine were observed to have a higher effect in patients with NVED in terms of inducing penile erection and decreasing CEA compared to their effects in patients with VED.

CONCLUSION

TPPS induces penile erection and decreases CEA for some extent, but to a lesser degree compared to papaverine. As further improvements are achieved in the methodology of TPPS, it may be a valuable method in the evaluation patients with erectile dysfunction.

Current trends in the treatment of infertility in men with spinal cord injury

OBJECTIVE

To determine current use of penile vibratory stimulation (PVS), electroejaculation (EEJ), and intrauterine insemination (IUI) in treatment of infertility in men with spinal cord injury (SCI).

DESIGN

Prospective survey, retrospective chart review, and literature review.

SETTING

Major university medical center.

PATIENT(S)

Male SCI patients and female partners.

INTERVENTION(S)

A survey administered to professionals determined current treatment methods for infertility in couples with SCI male partners.

MAIN OUTCOME MEASURE(S)

Sperm retrieval methods, ejaculation success rates, total motile sperm (TMS), IUI application, and IUI outcomes.

RESULT(S)

Twenty-eight percent of surveyed professionals do not retrieve sperm from ejaculates of SCI patients, relying instead on retrieval from reproductive tissues. Reasons for not offering PVS or EEJ were lack of familiarity, training, or equipment. Thirty-four percent do not offer IUI to these couples. Chart review showed that semen could be retrieved by PVS or EEJ in 95% of patients. Fifty-three percent and 43% of trials had TMS >5 and >10 x 10(6), respectively. Of survey respondents performing IUI, 42% lacked enough data to estimate pregnancy rates (PRs) in these couples. Literature review showed IUI PRs between 9% and 18% per cycle and 30% and 60% per couple.

CONCLUSION(S)

Based on ejaculation success rates, TMS yields, and IUI outcomes, the methods of PVS, EEJ, and IUI warrant consideration in centers not currently offering these options for couples with SCI male partners.

Fertility following spinal cord injury: a systematic review

STUDY DESIGN

Systematic review.

OBJECTIVES

To review systematically fertility of persons with spinal cord injuries (SCI) and their partners.

METHODS

Reports from six databases (1966-2003), selected annual proceedings (1997-2002) and manufacturer's information were screened against eligibility criteria. Searches covered female obstetrical issues, and the efficacy of vibration and electroejaculation for males, as well as advanced fertility (AF) treatments for partners of SCI males. Data were pooled from case-series reports on SCI males' ejaculation, and pregnancies and live births for partners of SCI males.

RESULTS

In all, 2,127 unique reports were evaluated, of which 66 reports were included. No studies investigated fertility in SCI females. Ejaculation interventions in the last decade resulted in response rates of 95% (95% confidence intervals (CI) 91%, 99%), with 100% response rate reported in several recent publications. A total of 13 studies (1993-2001) yielded pregnancy rates of 51% (95% CI 42%, 60%) in partners of SCI males. Of these, 11 studies (1993-2003) yielded live birth rates of 41% (95% CI 33%, 49%).

CONCLUSIONS

Fertility of SCI males is extensively studied. Semen for fertility purposes can generally be obtained using vibration and electroejaculation. AF techniques are increasing pregnancy rates. Research is needed to improve sperm quality. Freezing of sperm is unlikely to significantly improve fertility rates. Fertility of SCI females is addressed only in case reports and opinion articles. The opinion that female fertility is unaffected by SCI should be further investigated using appropriate research methodology.

Penile erection produced by microstimulation of the sacral spinal cord of the cat

The sacral neural pathways mediating penile erection in the cat were studied by measuring the change in cavernous sinus pressure (CSP) elicited by stimulation of the sacral ventral roots or by microstimulation of the sacral spinal cord. Ventral root stimulation revealed that the S1 segment rather than S2 and S3 spinal segments could evoke the largest CSP responses. Microstimulation in the S1 spinal cord elicited large CSP responses but small or no bladder contractions. Maximal CSP responses were evoked by microstimulation in the middle of the S1 ventral horn, 1.6-2.8 mm below the cord surface and midway between the midline and the lateral edge of the gray matter. The area was 200-400 microm wide (medial to lateral) and extended 1-2 mm in the rostrocaudal direction. Maximal CSP responses to spinal cord microstimulation were elicited by stimulus intensities of 50-150 microA, at a pulse width of 0.2 ms and at frequencies of 3040 Hz and occurred after delay of 8-40 s. This study suggests that focal microstimulation of the sacral spinal cord might be useful in eliciting penile erectile activity in patients with spinal cord injury.

Sperm-damaging effects of electric current: possible role of free radicals

The generation of reactive oxygen species (ROS) and sperm damage was evaluated in (a) samples obtained during electroejaculation (EE) of men with spinal cord injury and (b) in electrolyzed HAM's F-10 medium subjected to electric current in vitro. Chemiluminescence data showed a significant increase in ROS in the ejaculates (6 x 10(7) photons/ml) collected immediately after EE and in the electrolyzed medium (3 to 7 x 10(6) photons/ml) when compared to the control (4 to 7 x 10(4) photons/ml). Incubation of normal human sperm with the electrolyzed medium resulted in a significant threefold decrease in percent motility and a twofold decrease in percent viability. Sperm subjected to direct electric stimulation in vitro exhibited a significant twofold decrease in percent motility and percent viability. Superoxide dismutase (SOD) activity decreased significantly in sperm subjected to direct electric current in comparison to the control or the sample incubated with electrolyzed medium. These studies indicate that in vitro and in vivo electrical stimulation generate reactive oxygen species and affect SOD activity, which in part are responsible for decreased sperm motion and viability.

Laparoscopic implantation of electrodes for stimulation of the hypogastric nerve and the vas deferens in dogs

The minimal invasiveness of laparoscopy prompted us to investigate its use for placement of electrodes for stimulation of the hypogastric nerve and the vas deferens. In an acute canine model, pressure changes in the vas deferens secondary to electrostimulation were recorded. The laparoscopic approach included four ports. Monopolar cuff electrodes were placed around the hypogastric nerve and the vas deferens, and the leads of both were pulled through the abdominal wall. After multiple percutaneous stimulations (20 mAmp., 20 Hz. and 200 microsecond pulse width), the abdomen was opened through a midline incision to check the position of the electrodes. Electrostimulation was repeated with the abdomen open. Electrostimulation of both the hypogastric nerve and vas deferens resulted in marked pressure rises in the vas. These increases were similar in response to both surface and percutaneous stimulation. We thus believe that laparoscopic implantation of electrodes followed by percutaneous preliminary stimulation of the superior hypogastric plexus or the vas deferens may be a viable future approach to anejaculation.

Quality of semen after repeated ejaculation treatment in spinal cord injury men

The study was designed to document the effects of regular drainage after penile vibrator stimulation on the quality of semen in SCI men. Twenty three tetraplegics and 9 paraplegics, 18 to 40 years of age and with neurological levels ranging from C4 to L1, were examined between 1 and 23 years after injury (median 2 years). None had ejaculated after the injury. Penile vibrator stimulation was tried in patients with cervical or thoracic lesions who showed reflex hip flexion on scratching the soles of the feet, 29 out of 32, and rectal electrostimulation in the remaining 3 low lesions with no reflex function in lumbar and sacral segments. The stimulation yielded semen in 29 (91%) of the men; 22 had antegrade and 7 retrograde ejaculation. Sixteen of the 22 patients with antegrade ejaculation entered a home programme of vibrator stimulation prescribed once weekly. Four to 6 months of stimulation resulted in a rise of semen volume and of fructose and acid phosphatase levels in the seminal plasma, suggesting improved function of the seminal vesicles and the prostate. The percentage of motile sperms was low both before and after the treatment period. Despite this, the total count of motile sperms per ejaculate was already high in the patient's first ejaculates compared to the laboratory normal standard, and further clearly increased after the stimulation period. A standardised functional test measuring sperm penetration capacity showed strong evidence of long term stimulation effect. It is suggested that the test is used in the assessment of fertility potential in SCI men.

Electroejaculation in spinal cord injury patients: simplified new equipment and technique

A new simplified electrostimulation system for rectal probe electroejaculation has been developed and tested 17 times in 13 patients. Seminal emissions were obtained easily from 13 of 17 studies and partial emissions were obtained in 4. Patients with cauda equina and conus lesions with partial intact sensorium also could achieve successful ejaculation by longer stimulation from 2 to 5 minutes with lower currents that could be maintained easily and were tolerated by the patient--a feature unique to our new computerized equipment. The simplicity of operation reduces the number of trained personnel for an electrostimulation procedure, which can be done even in an outpatient setting.

The rat as a model for the study of penile erection

A model has been developed for the study of penile erection in the Sprague-Dawley rat. Anatomical dissections demonstrate a bilateral ganglion lateral to the prostate called the major pelvic ganglion. This ganglion receives input from the pelvic and hypogastric nerves and innervates the pelvic viscera. A large fiber from the major pelvic ganglion courses along the urethra and innervates the corpus cavernosum, the cavernous nerve. In 40 animals, electrical stimulation of either the cavernous nerve or the pelvic nerve resulted in reproducible repetitive tumescence of the corpora cavernosum. Following ablation of the cavernous nerve, electrical stimulation failed to produce erections. Standard mating behavior tests of mounting, intromission and ejaculation in 38 rats showed that surgical ablation of the cavernous nerve resulted in a decrease in the rate of intromissions and ejaculations compared with sham operated controls. Present models for the study of erection have been limited to the dog, monkey and cat. The rat model presented here offers several advantages over these existing models: 1) the cavernous nerve is easily identified, 2) electrical stimulation is easily accomplished and reproducible, 3) behavioral and neurophysiological studies are possible, and 4) animal purchase, housing, and maintenance costs are low. These advantages make this model a uniquely useful tool in the further study of penile erection.

Experience in vibratory and electro-ejaculation techniques in spinal cord injury patients: a preliminary report

More than 90 per cent of complete spinal cord injury patients have major fertility problems, depending upon the site and type of injury. During the last 5 years 34 patients were treated by vibratory and/or electrostimulation at our center, and semen was produced in all but 5. In 8 patients ejaculation was attempted by vibratory stimulation alone and in 22 electrostimulation also was used. Vibratory stimulation is the easier and less cumbersome of the 2 methods. No major side effects were noted with either technique. Stimulation was performed by a rectal electrode incorporated in a silicone finger glove with a current of 0.1 msec. in duration, a frequency of 30 Hz. and an average of 60 volts. Vibratory stimulation was applied to the frenulum and/or glans penis with a specially constructed vibrator at a frequency of 80 Hz. and a peak-to-peak oscillation of 1.6 to 2.4 mm. Semen obtained during the first 6 months after injury was not of a quality consistent with successful fertilization owing to poor motility. However, semen quality and motility were better in patients who had been injured for more than 6 months. Repeated electro-ejaculation did not improve the quality of semen. The effects of bladder outlet surgery and autonomic blockers were noted in 5 patients.

Rectal probe electrostimulation in the treatment of anejaculatory spinal cord injured men

This paper reviews our experience with rectal probe electroejaculation (RPE) which is part of a larger effort to determine the correlates of successful ejaculation and fertility in SCI men. RPE is performed in the outpatient clinic using specially designed rectal probes. Over the past 18 months, we have attempted RPE on 38 occasions in 12 subjects (eight paraplegics and four quadriplegics) with an age range of 23-38 years and 0.5-18 years since onset of injury. Anterograde ejaculation occurred in nine subjects with improvement in percent motility and total live sperm count on repeated stimulations in five subjects. Significant retrograde ejaculation occurred in one person and sperm acceptable for artificial insemination (AI) was obtained from four subjects. The major side effects were mild dysreflexia (three subjects) and disruption of a normal bowel program (one subject). We conclude that RPE is a safe, relatively brief outpatient procedure and, with repeated stimulations, has a good potential for producing sperm acceptable for AI in selected patients.

Ejaculatory stimulation in spinal-cord injured men

Anejaculation is a common problem among spinal-cord injured (SCI) men. Only 1-20 per cent of SCI men can ejaculate. Methods of ejaculatory stimulation are needed to obtain sperm for artificial insemination purposes. The methods of stimulation heretofore used include intrathecal neostigmine, rectal probe electro-ejaculation, vibratory stimulation of the penis, and subcutaneous physostigmine. Ejaculatory ability increased to as much as 58 per cent using these techniques, but complications such as nausea and vomiting, elevated blood pressure, and headaches have been reported. The mechanisms of action of these techniques are poorly understood; they are believed to stimulate either reflex spinal ejaculatory centers or efferent peripheral nerves from these centers. The studies with these techniques often fail to use scientific methods of evaluation and are deficient in characterizing the subject population, description of stimulator and technique utilized, definition and presentation of "success" and/or complications observed. The criteria by which future studies of ejaculatory stimulation should be measured are suggested.

Electroejaculation for recovery of semen after retroperitoneal lymph node dissection: case report

Electroejaculation with a rectal probe was used successfully for semen recovery 8 years after bilateral suprarenal hilar lymph node dissection for stage IIB embryonal cell cancer. An adequate ejaculate was obtained in relation to total sperm count, motility and normal morphology. Prior use of sympathomimetic drugs, including imipramine and ephedrine, was unsuccessful in producing an ejaculation. Electrostimulation via a rectal probe seems to be a useful technique for semen recovery in the patient with anejaculation after retroperitoneal lymph node dissection.

Infertility in spinal-cord injured male

Sterility in spinal-cord injured (SCI) men is believed to be caused by ejaculatory dysfunction, genital ductal blockage secondary to infection, and/or impaired spermatogenesis. Semen from SCI men demonstrates diminished numbers of motile, morphologically normal sperm. Testicular biopsies demonstrate impaired spermatogenesis. Leydig and Sertoli cells appear to be normal. Endocrine evaluations reveal normal testosterone levels with an adequate Leydig cell reserve. Luteinizing hormone (LD) and follicle-stimulating hormone (FSH) levels are normal or high with normal or exaggerated stimulation responses. Acute depressions in testosterone, FSH, and LH levels can be seen following SCI, most markedly in quadriplegics. A normal hypothalamic-pituitary-testicular axis is implied by these findings, indicating a primary hypogonadism. Causes of impaired spermatogenesis may include local testicular temperature elevations, nondrainage of the reproductive tract, antisperm antibodies, and recurrent genitourinary infections. Treatment of infertility involves removal of these offending factors, and research is needed to correlate the impaired spermatogenesis with these factors.

Operative recovery of vasal sperm from anejaculatory men: preliminary report

Sperm showing good motility and function, as demonstrated by the in vitro sperm penetration assay using hamster ova, were collected from the vas deferens of 3 men with ejaculatory failure. The collection procedure may be repeated over multiple ovulatory cycles. The sperm may be used to attempt artificial insemination or in vitro fertilization.

Reproductive biology of paraplegics: results of semen collection, testicular biopsy and serum hormone evaluation

The fertility and urological status of 30 male paraplegics between 20 and 47 years old with lesions between the T2 and L3 levels were examined by studying serum hormone levels (estradiol-17 beta, testosterone, prolactin, and follicle-stimulating and luteinizing hormones), sperm and semen characteristics via testicular biopsy and rectal probe electrostimulation, and urodynamic evaluation. Of the patients 13 had reflexic, 4 hyperreflexic and 13 areflexic bladders. Nine of the 13 patients with reflexic and all 4 with hyperreflexic bladders had a positive external sphincter electromyogram with detrusor-sphincter dyssynergia. When catheters were not used to collect semen during rectal probe electrostimulation, retrograde semen flow into the bladder was the rule. A total of 22 patients could tolerate rectal probe electrostimulation, while 6 who could not were injured at the T12 level or lower. Seminal emissions were obtained from 35 to 42 studies in these 22 patients. Total sperm count was variable; in 22 studies it was greater than 20 million. Progressive motility usually was low; 77 per cent of the patients had less than 20 per cent motility. Of 13 biopsy specimens obtained 6 suggested normal testicular morphology, with tubule atrophy and spermatogenic activity only mildly reduced in 6 of the remaining 7. Serum testosterone and luteinizing hormone values were significantly higher (p less than 0.05) among the paraplegic patients than among intact male volunteers of the same age range. Other serum hormone levels were unchanged. Outcome of rectal probe electrostimulation and biopsy did not relate to the number of years of patient injury. Thus, the principal deterrent to the use of semen collected by rectal probe electrostimulation from paraplegics for artificial insemination resides in a predominantly low sperm motility. Suggestions for improvement of motility include 1) great care to minimize or prevent urinary tract infections, 2) selection of medications for urinary tract care that do not compromise sperm survival and 3) prevention of sperm stagnation in lower tract storage sites, perhaps by use of periodical rectal probe electrostimulation.