Faculty Bibliography

PURPOSE/OBJECTIVE:We evaluated the calcium channel blocking activity of thioridazine, clomipramine and fluoxetine in isolated rat vas deferens and determined their relative order of potency. MATERIALS AND METHODS/METHODS:Cumulative control concentration-response curves to calcium chloride were obtained in isolated rat vas deferens incubated in depolarizing calcium-free Krebs-Henseleit solution. Tissues were washed to baseline length and equilibrated with a given concentration of test drugs. After a 30-minute period a calcium concentration-response curve was repeated. The resulting rightward displacement of the concentration-response curve to calcium provided a dose ratio. The dose ratio was used in the Schild equation and the antagonism of calcium induced contractions was quantified by Schild analysis. RESULTS:The calcium channel blocking activity of thioridazine, clomipramine and fluoxetine was compared with nifedipine. All 4 drugs produced parallel rightward displacement of concentration-response curves to calcium. The potency of this effect was quantified by Schild analysis showing pA estimates, namely nifedipine 7, thioridazine 6.2, clomipramine 5.65 and fluoxetine 5. CONCLUSIONS:A characteristic profile of calcium channel blocking activity on the vas deferens was obtained for all test drugs. The relative order of potency was determined as thioridazine greater than clomipramine greater than fluoxetine. Differences in the potency of calcium entry blockade at peripheral end organs may contribute to differential effects of these drugs on delaying ejaculatory latency in patients with premature ejaculation.

An association between congenital bilateral absence of the vas deferens (CBAVD), normal renal anatomy and cystic fibrosis (CF) gene mutations is well established (CF/CBAVD). We postulate that unilateral renal agenesis (URA) and CBAVD (URA/CBAVD) may have a non-CF mutation-mediated genetic basis that leads to abnormal development of the entire mesonephric duct at a very early stage in embryo development (< or =7 weeks). The physical, laboratory and radiographic findings of men with URA/CBAVD (n = 17) and CF/CBAVD (n = 97) were compared; the fertilization and pregnancy rates in the URA/CBAVD population calculated, and the incidence of renal agenesis in immediate family members and offspring of men with URA/CBAVD analysed. No statistical differences could be identified within any of the above comparisons. The fertilization rate for the URA/CBAVD group was 58.2 +/- 26.3%. Eight infants and two fetuses had normal renal anatomy, while one terminated male fetus had bilateral renal and vasal agenesis. Thirty first-order relatives had normal renal units. Anatomical expression of the reproductive ductal derivatives in men with URA/CBAVD and CF/CBAVD was similar, but the phenotypic outcome of the renal portion of the mesonephric duct was different. The potential for transmission of this fatal anomaly reinforces the need for prenatal ultrasounds with all pregnancies involving URA/CBAVD men.

OBJECTIVES/OBJECTIVE:To obtain data concerning the incidence and management of reservoir herniation in inflatable penile prosthesis surgery in a clinical investigation. Reservoir herniation after scrotal placement of inflatable penile prosthesis is an unusual complication, and a review of the published medical reports reveals only anecdotal reports and no definitive articles. METHODS:A multi-item self-addressed questionnaire was mailed to the members of the Society for the Study of Impotence questioning the occurrence of reservoir migration from the prevesical space to the inguinal canal or scrotum. In addition, the database of one of us was reviewed to determine the incidence of reservoir migration in a large series of 1206 three-piece penile prostheses. RESULTS:The response rate was 38%. A minority of respondents (28%) were familiar with the problem. Of those who had experienced this complication, the occurrence was very rare and usually appeared in the immediate postoperative period, often in association with vigorous coughing spells or vomiting. The responders also indicated that imperfect surgical technique might have been implicated in some cases. Management usually consisted of reservoir replacement or repositioning through an inguinal incision with repair of the defect. Alternatively, several surgeons used the existing scrotal incision if the patient presented in the immediate postoperative period. The incidence of reservoir herniation was 0.7%. CONCLUSIONS:Reservoir herniation is a rare complication of inflatable penile prosthesis surgery that occurs almost exclusively in penoscrotally placed prostheses. Familiarity with various approaches to the management of this complication is clinically useful to urologists performing penile prosthesis surgery.

BACKGROUND:Limits on the frequency of PSA testing and an endpoint for the age of the screened population have not been established. The numbers of performed serum PSA tests, cost evolution, and utilization patterns by various subspecialties in one medical center were analyzed to gain insight into trends in screening for early detection of prostate cancer and gather information about the appropriate use of PSA testing. METHOD/METHODS:Computerized records were reviewed for numbers of PSA tests obtained, prostate biopsies performed, and prostate cancer cases diagnosed in the VA NJ-Health Care System from 1996 to 1998. In addition, PSA tests performed during two representative weeks in 1996 and 1997 were analyzed to evaluate a smaller cohort of patients with regard to age, consequences of the test results in their management, and subspecialties ordering the tests. RESULTS:PSA testing increased steadily between 1992 and 1998, with the most significant change (152% increase) between 1997 (9,410 tests) and 1998 (23,684). Prostate cancer diagnoses by biopsy were 164/434 (37.8%) in 1997 and 195/507 (38.5%) in 1998. For the 14,274 additional PSA tests obtained in 1998, 31 more prostate cancers were diagnosed. Prostate cancer diagnoses per PSA tests were 164/9,410 (1.8%) in 1997 and 195/23,684 (0.8%) in 1998. Primary care providers ordered 61% of the PSA tests. CONCLUSIONS:Most PSA tests at this institution were ordered by general practitioners, and the number of PSA tests ordered for men over 75 was high. The dramatic increase between 1997 and 1998 was not accompanied by a similar rise in the diagnosis of prostate cancer, raising the possibility of indiscriminate PSA testing or unnecessary repetition of testing. Guidelines for prostate cancer screening and continued PSA testing in the geriatric population may need further clarification.

Urologists and health care professionals treating erectile dysfunction face a significant challenge in caring for the HIV-positive patient who seeks restoration of normal sexual function. The encounter between the health care provider and the patient in this setting requires knowledge of HIV disease and potential drug interactions specific to this population, as well as thorough counseling on strategies aimed at reducing the infectiousness of HIV-1. The interaction extends beyond the immediate boundaries of the doctor-patient relationship and their respective rights, to include careful consideration of the rights of the partner/s and the society as a whole. This paper is a summary and analysis of presentations and discussions by medical, legal, nursing and bioethics specialists in an interactive seminar on this topic.

AIM/OBJECTIVE:An improved understanding of the relationship between radial and axial rigdity values would enable better appreciation of the clinical usefulness of RigiScantrade mark, the most widely utilized determination of erectile rigidity testing. Previous studies have shown that axial rigidity (measured by buckling forces) correlated well with radial rigidity (measured by RigiScantrade mark) for radial rigidity values below 60%. For radial rigidity exceeding 60%, there was poor correlation. Heretofore, there has been no physiologic explanation of this phenomenon. METHODS:During dynamic pharmacocavernosometry in 36 impotent patients, we investigated the relationship between axial buckling forces and RigiScan radial rigidity and, for the first time, how they both vary with pressure, (which we varied over over a wide functional range). In addition, we recorded multiple penile length and diameter values enabling us to relate, also for the first time, axial and radial rigidity to individual mechanical erectile tissue and penile geometric properties. RESULTS:Marked differences were found in the manner RigiScan radial rigidity units and axial buckling force magnitudes increased with increases in intracavernosal pressure values in each individual. The former asymptotically approached a maximum finite value while the latter increased continuously towards infinity. Based on data in this study, RigiScan radial rigidity values greater than 55% may be considered a necessary criteria for vaginal intromission capability in all partners but it is not a sufficient one. CONCLUSIONS:Axial and radial rigidity share a common dependency upon intracavernosal pressure, however, they are also dependent upon other unique physical determinants. For axial rigidity, additional dependent variables include cavernosal erectile tissue properties and penile geometry, while for radial rigidity, this may include tunical surface wall tension properties. Clinical devices which assess functional penile rigidity should utilize axial and not radial rigidity testing.