P. Gary Katz

Visually Stimulated Erection in Castrated Men

Sexual interest and activity decrease following castration. We determined by objective criteria the erectile status of 16 men who were sexually active before castration for prostatic cancer. Castration was achieved by orchiectomy or hormonal manipulation. Patients answered a questionnaire regarding the medical status and erectile function before and after castration, and the blood level of testosterone was assessed. During viewing of an erotic videotape penile circumference and erection quality were monitored. Four patients (25%) achieved functional erection. Mean serum free testosterone levels in men who achieved erection were 1.125 +/- 0.362 pg./ml. (standard deviation) and 0.628 +/- 0.098 pg./ml. in those not achieving functional erection (p < 0.001). No statistically significant difference was noted in age, interval since castration, co-morbidity score or method of castration between the men who did and did not achieve erection.

Combining Intracavernous Injection and External Vacuum as Treatment for Erectile Dysfunction

We studied the effect of combining intracavernous injection and an external vacuum in 10 men with erectile dysfunction who previously failed attempts at treatment with either method as single therapy. We measured the length, circumference and buckling pressure of the penis at baseline, after applying negative pressure (250 mm. Hg for 2 minutes), 15 minutes after intracavernous injection of 60 mg. papaverine or 30 micrograms prostaglandin E1 and after combining both modalities. No patient achieved adequate rigidity (defined as a penile buckle pressure greater than 450 gm.) with single therapy. The mean buckle pressure using vacuum alone was 125.0 +/- 53.6 gm. After intracavernous injection the mean buckle pressure was 117.0 +/- 38.3 gm. In contrast, all 10 subjects responded to combination therapy with a mean buckle pressure of 565.0 +/- 56.8 gm. (p < 0.0001). After 10 months of followup 3 subjects were still using the combination and were satisfied with the erectile response, 1 found that he no longer needed the addition of external vacuum after using combination therapy for 3 months, 1 used the combination for 9 months and then stopped because of an intervening acute illness, 1 lost the partner due to death, 2 found combination therapy to be too cumbersome and 2 were lost to followup. We conclude that external vacuum devices can augment a partial response to intracavernous injection and the combination may be an alternative treatment before intrapenile prosthesis implantation.

Treatment of Erectile Failure with Prostaglandin E1: A Double-Blind, Placebo-Controlled, Dose-Response Study

We report a double-blind, randomized, placebo-controlled, dose-response study of prostaglandin E1 as treatment for erectile failure. A total of 15 men 55.8 +/- 9.2 years old with a mean duration of erectile dysfunction of 7.6 years participated. During phase 1 (double-blind) subjects received injections of prostaglandin E1 twice weekly at doses of 0 micrograms. (placebo), 2.5 micrograms., 5.0 micrograms., 7.5 micrograms. and 10 micrograms. During phase 2 (nonblind) the dose was increased until a full erection or intolerance developed. Response was measured using a RigiScan monitor. During phase 3 the subjects injected prostaglandin E1 at home. Of the subjects 66% achieved an erection adequate for intercourse, with an average rigidity of 59%. The dose-response curve reached a plateau at 5 to 10 micrograms. Among those responding to prostaglandin E1 intercourse was rated satisfactory by 81% of the subjects and by 90% of the partners. There were no prolonged erections requiring reversal and pain was reported with only 10% of the injections. In summary, intracavernous prostaglandin E1 is an efficacious and effective treatment for erectile failure.

Transurethral Incision of the Bladder Neck and Prostate

Between March 1983 and December 1988, 66 men 50 years old and older with symptomatic bladder outlet obstruction underwent transurethral incision of the bladder neck and prostate. Patients selected for incision had a small, clinically benign, prostate and peak urinary flow rate of less than 15 ml. per second. Preoperative and postoperative evaluation included symptom questionnaires and uroflowmetry. A single midline incision was made extending from the bladder neck to the verumontanum. Results were available in 64 of the 66 men who underwent the procedure with a mean followup of 2.24 years. Mean symptom scores decreased from 9.66 preoperatively to 4.59 postoperatively (p less than 0.001) and peak urinary flow rates increased from 7.4 to 14.7 ml. per second (p less than 0.0001). Antegrade ejaculation was preserved in 83.3% of the men who preoperatively had antegrade ejaculation. Subsequent transurethral resection of the prostate was required in 5 patients (7.6%). With a mean followup of greater than 2 years transurethral incision of the bladder neck and prostate was effective in treatment of bladder outlet obstruction caused by a small prostate while maintaining antegrade ejaculation in the majority of patients.

Arterial-Ureteral Fistula: Case Study with Review of Published Reports

Arterial-ureteral fistula, a rare cause of gross hematuria, may be associated with life-threatening hemorrhage if not rapidly diagnosed and treated. Recently, a patient at the Hunter H. McGuire Veterans Administration Medical Center developed an arterial-ureteral fistula at the site of the confluence of the external iliac artery and a superior mesenteric artery bypass graft. Review of the worlds literature revealed 31 additional reported cases of arterial-ureteral fistulas [1—31]. This current case is only the second one reported in which the diagnosis was made with arteriography. Several common features of arterial-ureteral fistulas were present in this case: a history of ureteral obstruction and urinary tract infections, upper urinary tract disease, and previous vascular surgery. The condition is usually associated with either prior upper urinary tract instrumentation or vascular surgery, and an antecedent period of intermittent hematuria, followed by life-threatening hematuria, is common. A high index of suspicion and early surgical intervention are required for successful management. The major surgical challenges are to establish unobstructed urinary drainage and restore vascular continuity. Exclusion of prosthetic material from potentially infected areas is mandatory.

The effect of vacuum devices on penile hemodynamics

External vacuum devices are being used increasingly for the management of erectile dysfunction. There is limited information regarding the effect of vacuum devices on penile blood flow and potential for ischemic penile injury. The penile xenon washout rate was measured before and after application of 2 vacuum systems in 15 subjects. Compared to flaccid state measurements the xenon washout rate did not change significantly with the Synergist Erection System but it was significantly reduced with the Osbon ErecAid System. However, the degree and duration of decrease in penile blood flow that may result in ischemic changes are unknown.

Erectile Failure in the Aged: Evaluation and Treatment

With aging, there are changes in both libido and erectile function. Although the majority of aged men remain interested in sex, less than 15% report continued sexual intercourse. The cause of this “libido‐potency gap” is due primarily to erectile failure.

Long-term Efficacy of a New Formulation of Prostaglandin E1 as Treatment for Erectile Failure

PURPOSE We determined the long-term efficacy of intracavernous injection of a new formulation of prostaglandin E1 (Caverject) as treatment for erectile failure. MATERIALS AND METHODS A prospective study was done at a university affiliated Veterans Affairs medical center. Subjects with erectile failure received injections of prostaglandin E1 at the office and self-administered injections at home for up to 18 months. RESULTS Of 16 patients who performed home injections 15 completed 6 months and 10 completed 18 months of therapy. Patient and spousal satisfaction with intercourse was 90% for months 1 to 6, and patient satisfaction was 95% for months 7 to 18. CONCLUSIONS Prostaglandin E1 was highly effective at producing penile rigidity and an erection with satisfactory vaginal intercourse.

Incidence of Penile Pain After Injection of a New Formulation of Prostaglandin E1

PURPOSE We determined the incidence of pain with injection of a new formulation of prostaglandin E1. MATERIALS AND METHODS A total of 63 subjects with erectile dysfunction underwent treatment with the new formulation of prostaglandin E1. Evidence of pain associated with injection was obtained by questionnaire and through questioning. RESULTS A total of 451 injections was given to 63 subjects in the office, with 16 episodes (3.5%) of pain in 10 (15.9%). Then, 680 injections were performed by 38 subjects at home, with 15 episodes (2.2%) of pain in 8 (21%). Pain was not dose related. CONCLUSIONS The new formulation of prostaglandin E1 is less likely to be associated with pain compared with alcohol based formulations.

The Lowest Effective Dose of Prostaglandin E1 as Treatment for Erectile Dysfunction

The recommended dose of prostaglandin E1 as treatment for erectile dysfunction has been reported to be 10 to 40 micrograms. However, adverse effects probably increase with increasing doses. We conducted a prospective, single-blind, dose-escalating study of prostaglandin E1 on 20 men with erectile dysfunction of various etiologies. The response to prostaglandin E1 was assessed by penile palpation and RigiScan rigidity monitoring. A total of 17 patients completed the study: 1 achieved rigidity with 1 microgram., 2 with 2 micrograms. and 4 with 3 micrograms. prostaglandin E1, while more than 70% achieved rigidity with 5 micrograms. or less and more than 80% had a full erection with 20 micrograms. Of 138 injections there were 2 episodes of pain after injection. We conclude that the often recommended starting dose of 20 micrograms. is too high. A more appropriate starting dose is 2.5 micrograms. with increments of 2.5 micrograms. until the lowest effective dose is achieved. This approach may lessen the major impediments to prostaglandin E1 use, that is burning and pain.