Evaluation of the azoospermic patient

Azoospermia is found in up to 10 to 20 per cent of the men who present to an infertility clinic. The main causes are testicular failure and ductal obstruction. Testicular biopsy remains the definitive test used to differentiate these 2 disorders. A retrospective study of 133 azoospermic men was performed to determine the accuracy and limitations of noninvasive variables in predicting testicular failure in an effort to limit the need for diagnostic testicular biopsy. Of 49 patients (37 per cent) with ductal obstruction a third had bilateral vasal agenesis. The remaining 84 azoospermic patients (63 per cent) had testicular failure. The results of the complete evaluation of these patients are described. Among the 101 patients with a testicular biopsy confirmed diagnosis there was a significant difference in testicular size (p less than 0.001), ejaculate volume (p less than 0.001) and serum follicle-stimulating hormone (p less than 0.001) between patients with testicular failure and those with ductal obstruction. The sensitivity and specificity of various parameters were determined. The best criteria to predict ductal obstruction preoperatively are a serum follicle-stimulating hormone level of less than 2 times greater than normal and the absence of bilateral testicular atrophy (100 per cent sensitivity and 71 per cent specificity). An algorithm for evaluation of the azoospermic patient is described such that all men with ductal obstruction and a minimal number with testicular failure undergo testicular biopsy.

Effects of varicocele on male fertility

Varicoceles are vascular lesions of the pampiniform plexus and are the most common identifiable abnormality found in men being evaluated for infertility. Despite the long history associated with varicoceles, there remains much controversy regarding their diagnosis and management. The purpose of this manuscript is to address three of the most pressing controversies: (i) the association of varicoceles with male infertility, (ii) whether varicoceles exert a progressive deleterious effect and (iii) the relationship of varicocele size and outcome following varicocele repair. The current literature is reviewed in an effort to answer these questions. Based upon this analysis, conclusions can be drawn regarding the best management of varicoceles in subfertile men, adolescents, young fertile men and men with subclinical varicoceles. Although there remain many controversies due to a paucity of data, there appears to be a significant difference between adults and adolescents with respect to a progressive deterioration of semen parameters and it is clear that subclinical varicoceles do not play a major role in male infertility.

Quantitative pathologic changes in the human testis after vasectomy. A controlled study

To determine whether there are any deleterious changes in the human testis after vasectomy, we obtained testicular biopsy specimens from 31 healthy men undergoing vasectomy reversal and from 21 healthy, fertile volunteers. Morphometric analyses of these specimens revealed a 100 per cent increase in the thickness of the seminiferous tubular walls (P less than 0.001), a 50 per cent increase in the mean cross-sectional tubular area (P less than 0.001), and a significant reduction in the mean number of Sertoli cells (P less than 0.01) and spermatids (P less than 0.01) per tubular cross section in the post-vasectomy group, as compared with the control group. Focal interstitial fibrosis was observed in 23 per cent of the specimens from the post-vasectomy group and in none from the control group. There was a significant correlation (P less than 0.01) between interstitial fibrosis and infertility in patients who underwent a surgically successful vasectomy reversal (sperm in the ejaculate). None of the other measured characteristics correlated with infertility after vasectomy reversal. We conclude that significant morphologic changes occur in the human testis after vasectomy. The presence of focal interstitial fibrosis was associated with a high incidence of infertility in this series.

Penile trauma: an etiologic factor in Peyronie's disease and erectile dysfunction

PURPOSE

It has been postulated that trauma to either the partially or fully erect penis is a potential cause of Peyronie's disease. In addition, it has been proposed that engaging in sexual relations with a partial erection due to mild impotence is a risk factor for the development of Peyronie's disease. This study was performed to determine whether patients with either Peyronie's disease or non-Peyronie's disease impotence had an increased rate of penile trauma compared with potent controls.

MATERIALS AND METHODS

We mailed surveys to 207 men who had been seen for management of Peyronie's disease, 250 impotent men without Peyronie's disease, and 275 age-matched urologic patients without a history of either impotence or Peyronie's disease. The survey inquired whether the individual had a history of penile trauma to the flaccid or erect phallus or injury during sexual intercourse. In addition, patients were questioned whether they had been engaging in sexual relations with a partial erection.

RESULTS

The mean age of the impotent patients was slightly less than both the Peyronie's disease patients and controls. A similar response rate to the survey was found among the 3 groups. The mean duration of illness was 6 years for Peyronie's disease and 10 years for impotence. The frequency of penile trauma of any kind was significantly greater in both the Peyronie's disease (40%) and impotence (37%) patients than in the controls (11%). There was no significant difference between the Peyronie's disease and impotence groups. However, the Peyronie's disease patients had a lower frequency of attempting sexual relations with a partial erection than the 2 other groups.

CONCLUSIONS

The results of this survey demonstrate a significantly higher incidence of penile trauma in both impotent patients and patients with Peyronie's disease compared with controls. This study demonstrates an association between penile trauma and both Peyronie's disease and impotence. The reduced incidence of engaging in sexual relations with a partial erection among the Peyronie's disease patients implies that partial impotence is not a predisposing factor for Peyronie's disease.

Puboprostatic ligament sparing improves urinary continence after radical retropubic prostatectomy

OBJECTIVES

To determine whether a puboprostatic ligament-sparing technique of prostatic apical dissection provided improved urinary continence after radical retropubic prostatectomy.

METHODS

A total of 43 men with clinically localized prostate cancer underwent radical retropubic prostatectomy (standard apical dissection in 25, puboprostatic ligament-sparing technique in 18). Patients were evaluated by independent observer questionnaire to determine their continence status. The questionnaire was tested in a control group of 25 men who had not undergone prostate surgery. The overall continence rate and time to achieve continence was compared between the two surgical groups. In addition, the clinical and pathologic stages and both the rate and location of positive margins were assessed.

RESULTS

Mean patient age and serum prostate-specific antigen values were not significantly different between the two groups. Clinical and pathologic stages were also similar. The mean follow-up period for the puboprostatic ligament-sparing group was 35 weeks compared with 57 weeks for the standard group (P < 0.05). The median time until continence was achieved after surgery was significantly shorter (P = 0.01) for the puboprostatic ligament-sparing group than for the standard method (6.5 and 12 weeks, respectively). However, the overall continence rate at 1-year follow-up for the two groups was similar (100% and 94%, respectively). The positive margin rate and location of positive margins were not different with the puboprostatic ligament-sparing technique.

CONCLUSIONS

The puboprostatic ligament-sparing technique improves the rapidity of return of urinary continence after radical prostatectomy without significantly enhancing overall continence or interfering with the therapeutic efficacy of the procedure.

Clinical efficacy of sildenafil citrate based on etiology and response to prior treatment

PURPOSE

We assess the clinical efficacy of sildenafil citrate and predictors of satisfactory outcome.

MATERIALS AND METHODS

All patients treated with sildenafil citrate within the first 6 weeks of its release were evaluated with a self-administered questionnaire before and at completion of therapy to assess etiology of erectile dysfunction, level of sexual function, libido, response to previous therapies, response to therapy with sildenafil citrate and quality of life. Sexual function was measured before and during therapy using an abbreviated version of the International Index of Erectile Function, with a successful outcome defined as a level of satisfaction of 4 or 5 on a 5-point scale.

RESULTS

Followup was obtained in 267 of the 308 patients who entered the study. Mean age plus or minus standard deviation was 61+/-9.6 years and duration of erectile dysfunction was 4.1+/-3 years. Overall satisfaction with sildenafil citrate for the entire patient population was 65% and response to prior therapies did not affect satisfaction. There was a significant positive correlation between baseline sexual function and response to sildenafil citrate but even patients with severe erectile dysfunction had a 41% satisfaction rate. Etiology of erectile dysfunction had a significant impact on satisfaction rate, with neurogenic causes of erectile dysfunction (diabetes, prostate surgery and so forth) having significantly lower rates than psychogenic or vasculogenic erectile dysfunction.

CONCLUSIONS

Sildenafil citrate is a highly effective oral agent for the treatment of erectile dysfunction in clinical practice. The best predictors for response to sildenafil citrate therapy are baseline sexual function and etiology of erectile dysfunction. However, we could not identify any patient characteristic that would predict absolute failure for sildenafil citrate therapy. Therefore, all patients with erectile dysfunction who do not have specific contraindications should be considered for sildenafil citrate therapy.

Incidence of varicoceles in men with primary and secondary infertility

OBJECTIVES

To determine whether varicoceles are more prevalent in men with secondary infertility than in men with primary infertility.

METHODS

The records of 2188 consecutive men attending three infertility centers were reviewed to determine the incidence of varicoceles in men with primary and secondary infertility. In addition, other factors affecting both male and female infertility were assessed in these patients.

RESULTS

The incidence of varicoceles was not significantly different between the 1447 men with primary infertility versus the 741 men with secondary infertility: 44% and 45%, respectively. The incidence of vasal agenesis was significantly greater in men with primary infertility (P < 0.001). In addition, the female partner was significantly older in couples with secondary infertility (P < 0.001).

CONCLUSIONS

These findings do not support the conclusion that varicoceles have a progressive adverse effect on fertility over time and suggest that further study is needed to determine whether varicocele repair is indicated in patients with normal semen parameters.

Transrectal ultrasonography of infertile men

OBJECTIVE

To determine normal transrectal ultrasonographic anatomy in young men and the frequency of abnormalities in the infertile population.

DESIGN

Transrectal ultrasonography was performed upon 30 fertile volunteers and 150 consecutive men referred for male factor infertility.

SETTING

A male fertility center.

RESULTS

Transrectal ultrasonography was normal in 60% of controls and 53% of infertile group. The frequency of hyperechoic lesions within the prostate was similar in controls (40%) and infertile men (39%). Müllerian duct cysts were present in 11% of the infertile men and none of the volunteers. Rectal exam was normal in all of the men.

CONCLUSIONS

Transrectal ultrasonography is more sensitive at detecting abnormalities of the seminal vesicles and prostate than rectal exam. Hyperechoic lesions within the prostate is frequently a normal finding. Müllerian duct cysts are more frequently observed in infertile men and may be a cause of ejaculatory duct obstruction.

Seminal vesicle aspiration in the management of patients with ejaculatory duct obstruction

Ejaculatory duct obstruction is a rare but significant cause of male factor infertility. Vasography is the current gold standard for the diagnosis of complete obstruction of the ejaculatory ducts. However, there is currently no reliable method to diagnose partial obstruction. We performed seminal vesicle aspiration under transrectal ultrasonographic guidance in 11 infertile men to assess the use of this diagnostic test in the evaluation and management of patients with ejaculatory duct obstruction. The absence of sperm within the seminal vesicle aspirate from 8 patients who had sperm in the ejaculate demonstrates that sperm are not normally present within the seminal vesicles. Numerous motile sperm were observed in the seminal vesicle aspirate from an azoospermic patient in whom vasography documented complete ejaculatory duct obstruction, demonstrating that sperm can reflux into the seminal vesicles in patients with distal obstruction. Two patients with suspected partial ejaculatory duct obstruction had sperm in the seminal vesicles. In conclusion, sperm are not normally present within the seminal vesicles and ejaculatory duct obstruction should be suspected in any patient with numerous sperm within the seminal vesicles.

Varicocele related testicular atrophy and its predictive effect upon fertility

Varicoceles are the most common reversible cause of male factor infertility, yet approximately 80% of men with varicoceles are fertile. Therefore, it is unclear whether all adolescents should undergo prophylactic varicocelectomy to prevent future infertility or whether a subgroup of patients who are at increased risk for future infertility can be identified and treated. Testicular size discrepancy or hypotrophy of the testis associated with a unilateral varicocele has been suggested as an indication for prophylactic varicocelectomy in adolescents. We examined 946 men attending a urological clinic for complaints other than infertility to determine whether testis size discrepancy was predictive of infertility in men with left varicoceles. A left varicocele was detected on physical examination in 211 men, of whom 173 (82%) had been able to father children and 38 (18%) had never fathered children. A group of 630 men without palpable varicoceles served as controls, including 528 (84%) with a history of fertility. Testicular size was measured using an orchidometer and the average testicular volume difference was obtained by subtracting left from right testicular volume. The mean testicular volume difference for the fertile men without varicoceles (1.6 +/- 0.3 ml.) was significantly lower than the fertile men with varicoceles (3.1 +/- 0.4 ml.) (p < 0.05) and infertile men with varicoceles (2.5 +/- 0.6 ml.) (p < 0.05). There was no significant difference between fertile and infertile men with varicoceles. This study confirms prior reports that the majority of men with left varicoceles are able to father children and that varicoceles cause significant ipsilateral testicular atrophy/hypotrophy. However, we were unable to demonstrate a correlation between loss of testicular volume and fertility status in men with left varicoceles. Further study is needed to identify the clinical parameters predictive of future infertility in adolescents with varicoceles.

Penile vascular evaluation of men with Peyronie's disease

A penile vascular evaluation was performed upon 95 consecutive men with Peyronie's disease (19 potent and 76 impotent) and 100 consecutive impotent men without Peyronie's disease to gain further understanding of the pathophysiology of erectile dysfunction in patients with Peyronie's disease. Only 1 of the 19 potent patients with Peyronie's disease had abnormal arterial blood flow by duplex ultrasonography and none had evidence of veno-occlusive dysfunction by either duplex ultrasonography or dynamic infusion cavernosometry/cavernosography. In contrast, 36% of the impotent men with Peyronie's disease had abnormal arterial blood flow and 59% had evidence of veno-occlusive dysfunction. There was no significant difference in historical risk factors for impotence between the impotent patients with Peyronie's disease and the control population of impotent patients. However, the presence of veno-occlusive dysfunction in the control population (16%) was significantly less than that of the impotent Peyronie's disease patients (p < 0.001). Although patients with Peyronie's disease may suffer impotence due to arterial occlusive disease, our results indicate that the principal cause of impotence in this patient population is veno-occlusive dysfunction.

Endocrine evaluation of infertile men

OBJECTIVES

To determine the incidence and type of endocrinologic abnormalities in men undergoing infertility evaluations and the most appropriate testing to detect them.

METHODS

A retrospective review of consecutive patients attending two infertility centers was performed. Results of endocrine testing were compared to medical history and physical and laboratory findings to determine whether endocrinologic screening could be limited to a specific subpopulation.

RESULTS

Only 99 of the 1035 patients (9.6%) had abnormal endocrine studies upon repetitive testing. The majority of these patients had an isolated elevation of serum follicle stimulating hormone (FSH) levels. Only 1.7% had a clinically significant endocrinopathy that would have had an effect upon disease management. Screening with serum testosterone and FSH levels alone was just as effective as a complete hormonal panel of testosterone, FSH, luteinizing hormone, and prolactin for the detection of clinically significant endocrinopathy. Only 1 patient with a clinically significant endocrinopathy would not have been identified if hormonal screening was limited to only those patients with a sperm density of less than 10 x 10(6)/mL.

CONCLUSIONS

Endocrinopathies are a rare cause of male infertility. Endocrine screening of men with sperm counts of less than 10 million/mL with serum testosterone and FSH levels alone will detect the vast majority of clinically significant endocrinopathies.

Placebo-controlled study of oral terbutaline and pseudoephedrine in management of prostaglandin E1-induced prolonged erections

Prolonged erections, priapism, secondary to pharmacologic stimulation are usually treated by drainage of the corporeal bodies and irrigation with a sympathomimetic. To study the efficacy of oral medical therapy in the treatment of priapism, 75 patients with pharmacologically induced (prostaglandin E1) prolonged erections were randomized to receive terbutaline, pseudoephedrine, or placebo. Detumescence occurred in 36 percent, 28 percent, and 12 percent, respectively. Terbutaline was significantly better than placebo (p < 0.05) in achieving detumescence. The results of this study suggest that oral terbutaline should be considered in the initial management of pharmacologically induced prolonged erections.

Ultrasonographic diagnosis of varicoceles

OBJECTIVE

To assess the ability of color duplex scrotal ultrasonography to detect subclinical varicoceles and confirm the diagnosis of clinical varicoceles.

DESIGN

Physical examination, color duplex scrotal ultrasonography and internal spermatic venography was performed on 64 testicular units in 33 men.

SETTING

Male fertility center.

PATIENTS

Two hundred sixty-two consecutive men being evaluated for male factor infertility of whom 33 agreed to undergo venography.

MAIN OUTCOME MEASURES

Ultrasonographic measurement of scrotal vein diameter of patients in the supine and upright position, before and during valsalva maneuver, and scrotal vein blood flow reversal with valsalva maneuver was compared with the findings of varicocele by physical examination and venography.

RESULTS

The best predictor of a varicocele was internal spermatic vein diameter, and the best overall performance of ultrasonography was achieved with the patient at rest in the supine position. The best cutoff point for venous diameter for a clinical varicocele was 3.6 mm and 2.7 mm for a subclinical varicocele, but the overall accuracy was only 63%.

CONCLUSIONS

Confirmatory studies are needed to support the ultrasonographic diagnosis of varicoceles before considering surgical repair.

Is routine endocrine testing of impotent men necessary?

Endocrine screening of impotent men is performed in an effort to identify a treatable cause of impotence. However, the prevalence of endocrinopathy in this patient population is low. We determined whether any historical or physical findings obtained during the initial office visit would identify a subgroup of patients at risk for endocrinopathy to decrease the cost of endocrine screening. The results of routine endocrine screening of 330 consecutive impotent patients formed the basis of this study. A total of 7 patients (2.1%) had endocrinopathy. Testicular atrophy was observed in 5 of these 7 patients and 6 reported decreased libido. All of the patients with endocrinopathy had either decreased libido or bilateral testicular atrophy. Our results indicate that the cost of impotence evaluation can be decreased by screening only those patients with clinical signs of hypogonadism, that is either decreased libido or bilateral testicular atrophy.

Effectiveness of laparoscopic varicocelectomy

Laparoscopic varicocelectomy is a new technique which has been described in a limited number of clinical reports. We reviewed the results of 46 patients undergoing laparoscopic repair of 75 varicoceles over a two-year period to assess the effectiveness of this operative technique. The internal spermatic artery was preserved in 80 percent of the varicoceles and two arteries were present in 5 percent. Our ability to preserve the internal spermatic artery improved significantly with the use of the intraoperative Doppler probe after the first six months of performing this operation (p < 0.01). Nineteen infertile patients had a minimum follow-up of twelve months with seminal improvement in 68 percent and a pregnancy rate of 26 percent. Complications occurred in 2 patients (4%), inferior epigastric vessel bleeding in one, and genitofemoral nerve injury in the other. There was one persistent varicocele (1%). Our results with laparoscopic varicocelectomy are comparable with those reported with standard open surgical approaches.

Seminal vesicle aspiration in spinal cord injured men: insight into poor sperm quality

PURPOSE

In men with spinal cord injury poor quality semen is seen when performing electroejaculation and penile vibratory stimulation. We determined whether sperm stasis within the seminal vesicles is a potential cause of this problem.

MATERIALS AND METHODS

Seminal vesicle aspiration was performed immediately before electroejaculation or penile vibratory stimulation in men with aspermia secondary to spinal cord injury. Sperm count and quality of seminal vesicle aspiration and subsequent ejaculation were compared with historical ejaculated counts, ultrasound findings and patient characteristics.

RESULTS

Mean total number of right plus left seminal vesicle sperm plus or minus standard deviation was 511 +/- 960 x 10(6). Mean total number of sperm obtained by seminal vesicle plus electroejaculation or penile vibratory stimulation was 918 +/- 1,261 x 10(6). Average motility and viability of the seminal vesicle aspirated sperm were 1.3 and 3.2%, respectively. Average motility of the ejaculated sperm was 26.4% after seminal vesicle aspiration versus 16.3% in previous ejaculation induction procedures performed in the same patients. Seminal vesicle aspirated sperm represented 66% of the total number of sperm obtained during the session and was equal to 49% of the sperm obtained at previous electroejaculation or penile vibratory stimulation sessions. The period of abstinence correlated only with ejaculate count (simple regression p = 0.009). No other clinical characteristics had any effect on sperm count or quality.

CONCLUSIONS

Large numbers of poor quality sperm are present within the seminal vesicles of spinal cord injured men and these sperm comprise a large portion of the specimens collected by electroejaculation or penile vibratory stimulation. This phenomenon is independent of the period of abstinence, implicating disordered storage of sperm due to spinal cord injury rather than infrequent ejaculation. The large number of senescent sperm within the seminal vesicles appears to be a primary cause of poor sperm quality in spinal cord injured men.

Effect of obesity and fertility status on sex steroid levels in men

Endocrine studies were performed on fertile and infertile obese men and compared with fertile and infertile nonobese men in order to determine the independent and codependent effects of obesity and fertility status on the male hypothalamic-pituitary gonadal axis. The obese infertile group exhibited significant endocrinologic changes as compared with fertile nonobese control group which was not observed in any of the other three groups. Serum testosterone was significantly lower. The testosterone/estradiol ratio was significantly lower despite a lack of significant change in serum estradiol levels. Serum steroid hormone binding globulin (SHBG) was significantly lower which correlated with elevated bioavailability of both testosterone and estradiol in the obese infertile group. Serum luteinizing hormone levels were no different, suggesting that free testosterone levels were unchanged. Obese infertile men exhibit endocrinologic changes that are not observed in men with either obesity or infertility alone. Reduction of serum SHBG, total testosterone, and testosterone/estradiol ratio appear to be a marker of infertility among obese men.

Physiologic variations of serum testosterone within the normal range do not affect serum prostate-specific antigen

OBJECTIVES

To determine the relationship between endogenous total serum testosterone levels and serum prostate-specific antigen (PSA) concentrations. If a correlation exists between these two parameters, then use of testosterone-specific reference ranges may enhance the utility of PSA as a marker for prostate cancer.

METHODS

Data were obtained from 150 men without previous history of prostate cancer. PSA was measured by the Abbott IMX microparticle enzyme immunoassay and total testosterone determined by the Coat-A-Count radioimmunoassay.

RESULTS

No correlation was found between testosterone and PSA, even when corrected for age and weight.

CONCLUSIONS

The data suggest that determination of the total serum testosterone level does not improve the sensitivity or specificity of PSA as a tumor marker.

Association of antisperm antibodies with chronic nonbacterial prostatitis

Antisperm antibodies are significant in male factor infertility. The prevalence of antisperm antibodies in the infertile population is approximately 10 percent, and it is not cost-effective to test for these antibodies in every male partner of an infertile marriage. Earlier studies have demonstrated a higher prevalence of antisperm antibodies among men with a history of bacterial prostatitis or urethritis. Because of this established association, we measured the prevalence of serum antisperm antibodies, using a gel agglutination assay, in 28 men with chronic nonbacterial prostatitis and in age-matched control group of 69 men without a history of prostatitis. The prevalence was 25 percent (test subjects) and 7.2 percent (controls) (p less than 0.05). This finding indicates that nonbacterial prostatitis is a risk factor for the presence of serum antisperm antibodies and that subfertile men with a history of nonbacterial prostatitis should be tested for these antibodies.

Relationship between antisperm antibodies and testicular histologic changes in humans after vasectomy

OBJECTIVE

To determine whether or not there is an association between testicular histologic changes and antisperm antibodies in vasectomized men.

METHODS

Morphometry was performed on testicular biopsy specimens obtained from 19 vasectomized men and 21 fertile control subjects. Antisperm antibody status was determined on the serum of each patient and control subject using the indirect immunobead assay.

RESULTS

Significant increases in seminiferous tubule wall thickness (p < 0.001), focal interstitial fibrosis (p < 0.001), and percent composition of interstitium (p < 0.01) were observed in vasectomized men as compared with control subjects. Serum antisperm activity was present in 74 percent of the vasectomized men but none in the control subjects (p < 0.001). There was no association between testicular histologic changes and immune status.

CONCLUSIONS

Vasectomized men exhibit significant testicular histologic changes and increased autoimmune activity as compared with fertile control subjects. These histologic changes are not directly associated with antisperm antibody status, suggesting that some other pathophysiologic process must be responsible.

Risk factors for male partner antisperm antibodies

The role of antisperm antibodies in human infertility remains controversial. Indications for antisperm antibody testing of male partners of infertile marriages have been based upon anecdotal reports and studies using outdated assays. In an effort to define the indications for antisperm antibody testing of the male partner, the immunobead assay for antisperm antibodies was performed upon 100 consecutive men referred for evaluation of male factor infertility. The prevalence of antisperm antibodies in this patient population was 18% and only 9% when patients with a history of vasectomy were excluded. Of all the factors analyzed, only a history of vasectomy and sperm agglutination on semen analysis were predictive of antisperm antibody status (p < 0.001). Use of the aforementioned parameters as an indication for antisperm antibody testing would have resulted in a sensitivity of 94%, specificity 73% and negative predictive value 98% in this patient population. The only way to identify all patients with significant levels of antisperm antibody activity (sensitivity 100%) would have been to test every patient.

Risk factors for papaverine-induced priapism

Intracorporeal administration of papaverine hydrochloride is frequently used in the diagnosis and treatment of impotence. Priapism is the most serious potential complication of its use. The historical characteristics of 400 consecutive men receiving a standardized dose of papaverine were reviewed in an effort to determine the risk factors for prolonged erections. Younger men (p less than 0.0001) with better baseline erectile function (p less than 0.023) were more likely to have priapism. Despite use of a significantly lower dose, patients with overt neurological disease also had an increased rate of priapism. Patients with a history of coronary artery disease had a significantly lower risk of priapism (p less than 0.05). Patients with a final diagnosis of either psychogenic or neurogenic impotence had a much greater risk of priapism than those with vasculogenic impotence (p less than 0.001). The initial dosage in pharmacological erection therapy may be adjusted according to these risk factors. However, not all patients with psychogenic or neurogenic impotence had priapism and some patients with vascular disease did have priapism. Therefore, all impotent patients are potentially at risk for pharmacologically induced priapism.