Veno-occlusive Dysfunction Research Articles

Evaluation of Erectile Function in Renal Transplant Recipients

RECTILE dysfunction describes the inability to achieve and maintain penile erection sufficient for coitus. Renal insufficiency is a chronic disease during which erectile function deteriorates, however, the etiology of this condition in such patients is multifactorial, involving organic and nonorganic (psychogenic) factors. 1 The condition may result from neuroendocrine disturbance, uremia, hypoxia, and atherosclerosis. 2 Neuroendocrine disturbance is often reversed by renal transplantation, but not by dialysis. 3 Psychological factors may also cause erectile dysfunction in dialysis patients, since approximately one fourth of these individuals are depressed at any given time. 4 Patients often regain potency after transplantation but in some cases, especially second transplantations, erectile function is adversely affected by interference with arterial blood flow. In this study, we evaluated the effect of renal transplantation on erectile function. PATIENTS AND METHODS Information on erectile function was collected by means of a questionnaire given to 65 men who were renal transplant recipients. The patients ranged in age from 20 to 57 years (mean 42.5 years). A second transplantation had been performed in four cases (6%). Posttransplantation follow-up ranged from 2 to 168 months (mean 72 months). A detailed medical history was taken and complete blood count, urinalysis, and a biochemical and endocrinologic blood analysis were routinely performed for all patients. A papaverine test, penile Doppler ultrasonography, cavernosometry, cavernosography, and pudendal angiography were done where indicated. For patients who had no erectile dysfunction before or after renal transplantation, the questionnaire and routine tests completed the evaluation. This group was considered to have experienced no change in erectile function due to renal transplantation. Similarly, no further tests were performed on patients who were afflicted with erectile dysfunction prior to renal transplantation but regained sexual function following transplantation. These patients were defined as the group with improved sexual function. On the other hand, patients with deteriorated erectile function after renal transplantation were evaluated in detail. All underwent a papaverine test involving intracavernous injection of 50 mg of papaverine and observation of response after 30 minutes. The group which experienced full erection after papaverine treatment (papaverine responders) was considered to have nonorganic (psychogenic) erectile dysfunction. Patients who did not respond to papaverine were further evaluated by penile Doppler ultrasonography for vasculogenic impotence. Papaverine-stimulated penile Doppler ultrasound was performed using a 7.5-MHz linear probe. Peak systolic velocities in the cavernous arteries were measured bilaterally. A peak systolic velocity of ,25 cm/s was considered as arterial insufficiency. Patients with arterial insufficiency underwent pudendal angiography, while those with normal penile Doppler ultrasound findings underwent dynamic infusion cavernosometry and cavernosography to assess for suspected veno-occlusive dysfunction. RESULTS Thirty-two patients (49.2%) experienced no alteration in erectile function before or after renal transplantation. Twelve patients (18.4%) said they regained erectile function after renal transplantation. Twenty-one patients (32.3%) with normal erectile function prior to transplantation during the hemodialysis period reported erectile dysfunction after the transplantation, constituting the group which was evaluated further. Seven of these patients were papaverine responders (nonorganic impotence) and benefited from antiserotoninergic treatment. All seven men received 150 mg/d trazodone initially, however, two patients who reported severe side effects with this drug were switched to sertraline at a dose of 50 mg/d. All patients in this group achieved erections sufficient for coitus within 3 months. In three patients, deterioration of erectile function was associated with hyperprolactinemia accompanied by a low testosterone level. A papaverine test was not performed in these cases. Oral testosterone replacement resulted in improved sexual function. Eleven of 21 patients who reported a deterioration in erectile function after transplantation did not respond to papaverine. These individuals were considered to have vasculogenic impotence. According to penile Doppler ultrasound, nine of these men had arterial insufficiency, while two had normal peak systolic velocities in their cavernous arteries, indicating no arterial insufficiency. These two patients underwent cavernosometry and cavernosography, which confirmed veno-occlusive dysfunction. They were treated with deep dorsal vein embolization using n-butyl cyanoacrylate, and regained satisfactory erections within 3 months, at which time control cavernosometry was normal.

Comparative Study between Corpus Cavernosum‐Electromyography Findings and Electron Microscopy of Cavernosal Muscle Biopsies in Erectile Dysfunction Patients

Biopsy and electrical activity recordings of the corpus cavernosum are 2 new diagnostic methods for the evaluation of impotent men. We evaluated the corpus cavernosum ultrastructure and electromyography (EMG) recordings from patients with erectile dysfunction. Twenty erectile dysfunction patients with veno-occlusive dysfunction underwent a detailed history, physical examination, biochemical tests, hormonal analysis, injection of an intracavernous vasoactive agent (60 mg papaverine-HCl), color penile Doppler ultrasonography, cavernosometry/ cavernosography and corpus cavernosum electromyography (CC-EMG). Thirteen patients underwent total vein ligation and 7 had penile prosthesis implantations. Tissue samples were obtained during surgery from both corpora cavernosa and examined by transmission electron microscopy. Control corporal tissue samples were taken from 3 cadavers. In 15 patients, CC-EMG recordings were 15.6 +/- 0.65 microV in the flaccid state, which decreased in 13 patients after papaverine (5.61 +/- 0.25 microV; P < 0.001). Five patients with diabetes mellitus had low amplitudes in the flaccid state (5.26 +/- 0.45 microV), which did not vary significantly after a papaverine injection (4.99 +/- 0.75 microV). The pathology of the corpus cavernosum biopsy specimens revealed a smooth muscle cell thickened basal membrane, dilated rough endoplasmic reticulum, and increased numbers of fibroblasts, but ultrastructurally normal endothelial cells lining the sinusoids. There was no difference between samples from diabetic or nondiabetic patients, or from either side of the corpora cavernosa. The only pathologic change observed in the controls was mitochondrial swelling. CC-EMG is less invasive and a valuable method in patients with erectile dysfunction, whereas no specific findings were observed from penile biopsy specimens.

Long-term results following dorsal penile vein ligation in 126 patients with veno-occlusive dysfunction.

One hundred and forty-seven patients who had dorsal penile vein ligation (DPVL) between 1987 and 1996 were re-investigated either during clinical consultation or by standardised telephone interview respectively questionnaire. One hundred and twenty-six patients were available for long-term follow-up. Postoperative outcome was classified into complete spontaneous erection, postoperative response to pharmacotherapy or no satisfactory improvement. The short-term success after 1-3 months according to this classification was 31 (24.6%), 25 (19.8%) and 70 (55.6%). These results were found to have deteriorated on long-term observation; with only 14 (11.2%), 24 (19.0%) and 88 (69.8%) respectively. Positive prognostic factors were preoperative duration of erectile dysfunction of < or = 7 y, a normal CC-EMG and a maintenance flow of < or = 45 ml/min. With all three parameters present, longterm success (spontaneous erection plus responder to intracavernous injection) rose from 30 to 67% in this selected group (P < or = 0.001). Our study shows that long-term success for unselected patients undergoing DPVL is disappointing; however, careful patient selection significantly improves long-term results.

RECOVERY OF SPONTANEOUS ERECTILE FUNCTION AFTER NERVE-SPARING RADICAL RETROPUBIC PROSTATECTOMY WITH AND WITHOUT EARLY INTRACAVERNOUS INJECTIONS OF ALPROSTADIL: RESULTS OF A PROSPECTIVE, RANDOMIZED TRIAL

This study was aimed at assessing prospectively the effect of postoperative intracavernous injections of alprostadil on the recovery of spontaneous erectile function after nerve-sparing radical retropubic prostatectomy. A total of 30 potent patients with clinically localized prostate cancer (clinical stage B1 or B2, Gleason sum 7 or greater, prostatic specific antigen less than 20 ng./ml.) underwent nerve-sparing radical retropubic prostatectomy and was subsequently randomized to alprostadil injections 3 times per week for 12 weeks (group 1, 15 patients) or observation without any erectogenic treatment (group 2, 15 patients). Patients were assessed at the 6-month followup by sexual history, physical examination, color Doppler sonography of the cavernous arteries and polisomnographic recording of nocturnal erections. In group 1, 12 patients (80%) completed the entire treatment schedule and were evaluated at the long-term followup. Eight patients in this group (67%) reported the recovery of spontaneous erection sufficient for satisfactory sexual intercourse, compared with 3 patients (20%) in group 2. The difference between the 2 groups was statistically significant (p <0.01). In group 1, all but 1 patient reporting normal postoperative erections also showed normal erections at nocturnal testing, whereas color Doppler sonography demonstrated normal penile hemodynamics in all of them. In these patients, failures were the result of cavernous veno-occlusive dysfunction (2 cases, 17%) and cavernous nerve injury (2 cases, 17%). In group 2, patients with normal erections showed both normal nocturnal testing and penile hemodynamics, whereas failures were the result of cavernous veno-occlusive dysfunction (8 cases, 53%), cavernous arterial insufficiency (2 cases, 13%) or cavernous nerve injury (3 cases, 20%). Complications in patients treated with alprostadil injections accounted for 2 cases (13%) of a penile nodule and 1 further case (6%) of prolonged penile erection. Complications were not seen in group 2 patients. Early postoperative administration of alprostadil injections significantly increases the recovery rate of spontaneous erections after nerve-sparing radical retropubic prostatectomy. It is our belief that programmed vasoactive injections improve cavernous oxygenation, thereby limiting the development of hypoxia-induced tissue damage. The potential complications related to the use of intracavernous injections must be clearly explained to patients.

Contractility Changes of the Deep Dorsal Penile Vein Due to Serotonin

Purpose Penile erection is a complex neurovascular phenomenon that takes place with the active contribution of arterial and sinusoidal structures. However, some authors claim that larger veins including the deep dorsal veins that produce contractions, might be involved in the physiology of erection. This study was designed to clarify the contractile properties of deep dorsal penile veins (DDPV). Materials and Methods The effect of serotonin (5-HT), noradrenaline (NA), adenosine triphosphate (ATP) and acethylcholine (Ach) on the isolated DDPVs of 16 impotent men, 9 with veno-occlusive dysfunction and 7 without venous leakage, and 5 potent men (controls) who underwent radical prostatectomy, were examined in vitro. Results Although NA, ATP and Ach had no effect, 5-HT produced concentration-dependent contractions. E max and pEC 50 of 5-HT were 411 +/− 10 mg., 5.92 +/− 0.25; 1020 +/− 260 mg., 5.83 +/− 0.24 and 160 +/− 40 mg., 6.4 +/− 0.22 in controls and patients who had venous leakage and no venous leakage, respectively. Samples of controls were contracted only with 5-HT 2 agonist, DOI (pEC 50 = 5.63 +/− 0.02), and these contractions were antagonized with 5-HT 2 antagonist ketanserin. On the other hand, both DOI (pEC 50 = 6.30 +/− 0.77) and 5-HT 1 agonist, 5-CT (pEC 50 = 6.23 +/− 0.21) produced venoconstriction in patients with veno-occlusive dysfunction. Conclusions The present findings suggest that 5-HT receptor functions in the DDPVs are of 5-HT 2 subtype in potent men and the altered response to 5-HT in patients with veno-occlusive disease may play a role in the pathophysiology of impotence.

Corporeal Veno-Occlusive Dysfunction: Predominantly Intracavernous Muscular Pathology

Purpose We investigated whether a relationship exists between the flow to maintain an erection obtained at cavernosometry and the alteration of intracavernous structures in impotent patients with corporeal veno-occlusive dysfunction and normal arterial inflow. Materials and Methods Computerized histomorphometric analysis of smooth muscle and elastic fibers, and endothelial cells was compared to the flow necessary to maintain erection after intracavernous vasoactive drug injection in 18 patients with corporeal veno-occlusive dysfunction. Results A significant correlation between percentage of smooth muscle fibers and flow to maintain erection was observed, while no correlation was noted with elastic fibers and endothelial cells. Conclusions Corporeal veno-occlusive dysfunction seems to be due mainly to smooth muscular alterations. According to this observation treatment of impotent patients with this abnormality should not be restricted to the penile veins but should also include the intracavernous structures, predominantly the muscular component.

Relationship Between Cavernosal Ischemia and Corporal Veno-Occlusive Dysfunction in an Animal Model

It has been postulated that cavernosal tissue ischemia secondary to arterial occlusive disease is associated with corporal veno-occlusive dysfunction. The goal was to correlate, for the first time, direct local intracavernosal blood flow measurements as a measure of cavernosal tissue perfusion with the integrity of corporal veno-occlusion in an animal model of vasculogenic impotence. The New Zealand White rabbit model of vasculogenic impotence was utilized (7 control, 9 atherosclerotic). After 16 weeks, intracavernosal blood flow was recorded directly by laser Doppler flowmetry. The relationships among peak intracavernosal blood flow, equilibrium intracavernosal pressure and corporal veno-occlusive function (as determined by intracavernosal pressure decay) were examined. Significant differences in the atherosclerotic compared to control animals were noted in iliac artery blood flow (12 +/- 4 vs 31 +/- 7 ml./min.), peak intracavernosal blood flow during erection (16 +/- 7 vs 25 +/- 4 ml./min./100 gm. tissue), equilibrium intracavernosal pressure (48 +/- 11 vs 72 +/- 6 mm. Hg) and intracavernosal pressure decay (57 +/- 17 vs 36 +/- 8 mm. Hg). Peak intracavernosal blood flow during erection was found significantly related to both equilibrium pressure (r = 0.75) and cavernosal pressure decay (r = -0.8). Abnormal intracavernosal blood flow (cavernosal ischemia) secondary to arterial occlusive disease predicts abnormal veno-occlusive function and poor erection quality.

Sexual Dysfunction in Peyronie's Disease: An Analysis of 222 Patients Without Previous Local Plaque Therapy

We obtained an objective evaluation of erectile function in patients with Peyronie's disease. Sexual dysfunction was analyzed in 222 patients with Peyronie's disease without previous local plaque therapy using a standardized protocol. Of the 222 patients 70 (31.5%) complained of not being able to perform intercourse. In 4 men (1.8%) standardized diagnostic procedure demonstrated only a severe angulation making coitus impossible, and in 3 men (1.4%) intercourse became unsatisfactory due to pain. Seven men (3.1%) reported distal penile flaccidity, including 4 in whom dynamic pharmacocavernosometry and pharmacocavernosography revealed veno-occlusive dysfunction. Of 56 men who complained of a complete loss of erection 51 did not respond to intracavernous pharmacological injection with prostaglandin E1, and 27 (48.2%) had abnormal arterial blood flow as shown by duplex sonography of the cavernous arteries, 47 (83.9%) had evidence of veno-occlusive dysfunction based on cavernosometric criteria and 33 (58.9%) also had cavernosographic evidence of the condition. Plaque associated venous drainage was evident in 15 of the 56 impotent patients (26.8%), equivalent to 45.5% of all cases with abnormal cavernosographic findings. Sexual dysfunction was evaluable in 31.5% of patients, and the main cause of impotence and loss of erection was veno-occlusive dysfunction.

Is deep dorsal vein arterialization an alternative surgical approach to treat venogenic impotence?

Several surgical techniques have been applied for the treatment of cavernosal venous leakage, sufficient enough to create erectile dysfunction. In light of the variable success rates, we report our experience with deep dorsal penile vein arterialization for the management of severe cavernosal venous leakage. Twenty-four impotent patients with venous leakage were treated by the Virag-II type of end-to-end anastomosis of the inferior epigastric artery to the deep dorsal penile vein and ligation of the vein proximally. Diagnostic evaluation included color flow Doppler sonography before and after intracavernous 60 mg papaverine injection and dynamic cavernosometry/ cavernosography, which indicated veno-occlusive dysfunction in 28 patients. Revascularization was technically possible in 24 of the patients, although in 4 anastomosis could not be achieved due to the poor quality of the inferior epigastric artery. Five patients had early occlusion in the immediate postoperative period and 4 had late occlusion within 8 months. Potency was improved initially in 9 (38%) of the 24 patients in whom successful anastomosis had been achieved, with longer term improvement in 6 (25%) of 24 who realized restoration of erectile potency as defined by clinical investigations. The mean follow-up was 24 months (range 3-36 months). We believe that anastomosis of the inferior epigastric artery to the deep dorsal penile vein and ligation of the vein proximally in cases of venous leakage results in a low success rate due probably to a pancavernosal alteration in corporal tissue compliance.

Does the positive intracavernous papaverine test always indicate a normal penile vascular system?

A positive intracavernous papaverine test has been presumed to determine normal erectile hemodynamics. Recently, positive erectile responses to intracorporeal injection tests were reported in patients with penile arterial insufficiency. This hypothesis was assessed by obtaining hemodynamic data using color Doppler ultrasonography in 417 patients with erectile dysfunction aged between 20 and 73 years (mean 43.06 +/- 13.66). A normal penile vascular system was found in 95 patients (22.79%), veno-occlusive dysfunction in 76 (18.22%), arteriogenic erectile dysfunction (ED) in 113 (27.10%) and mixed-type ED in 133 (31.89%). A positive erection response was achieved in 176 patients with combined intracavernosal injection of 60 mg papaverine and self-manual genital stimulation (CIS) test, while a negative response was observed in the remaining 241 (57.79%). Color Doppler ultrasonography combined with pharmacological erection has proved a normal penile vascular system in 94 (53.41%) and penile arterial insufficiency in 82 (46.59%) patients of those who gave a positive response to the CIS test. Also, a positive CIS test response was observed in all patients with unilateral arterial insufficiency (n = 31) and in 51 patients (62.19%) out of 82 with bilateral arterial insufficiency. A positive intracavernous papaverine test indicates veno-occlusive dysfunction competence but does not necessarily signify a normal penile arterial system. The CIS test should be combined with color Doppler ultrasonography in order to determine the vascular component of ED, since the differentiation is not possible between slight penile arterial insufficiency and psychogenic or neurogenic impotence with the CIS test.

Diffuse Veno-Occlusive Dysfunction: The Underlying Hemodynamic Abnormality Resulting in Failure to Respond to Intracavernous Pharmacotherapy

Purpose We established hemodynamic predictors of response to intracavernous pharmacotherapy. Materials and Methods Specific characterization and quantification of hemodynamic abnormalities of the cavernous arterial inflow and corporeal veno-occlusive mechanism associated with failure to respond to intracavernous pharmacotherapy were performed retrospectively in 69 patients with nonendocrinological impotence. We investigated atherosclerotic vascular risk factors, duplex ultrasonography peak systolic and end diastolic velocities (10 microgram prostaglandin E1), and dynamic infusion cavernosometry and cavernosography parameters (60 mg. papaverine and 6 mg. phentolamine). Results The patients were stratified by severity of the various hemodynamic parameters encountered and mean dose required for response. Response subsequently was characterized as excellent (75 percent or greater rigid erections) in 36 patients, adequate (erections sufficient for intromission) in 17 and poor or absent in 16. Psychogenic, neurogenic and mild vasculogenic causes were noted in patients with an excellent response. The adequate responses included all 3 cases with mild to moderate vascular etiologies whereas patients with a poor or no response had only severe venogenic and combined arteriogenic and venogenic etiologies. Mean flow-to-maintain values plus or minus standard deviation of 9.7 plus/minus 3.7, 10.8 plus/minus 9.5 and 59.5 plus/minus 24.2 ml. per minute were demonstrated in the excellent, adequate and poor or no response groups, respectively. There was a good correlation between mean flow-to-maintain values and mean doses of our standard vasoactive solution (r 2 = 0.88, p less than 0.0001). Pharmaco-cavernosography demonstrated diffuse or pan-cavernous corporeal veno-occlusive dysfunction in the poor or no response group. Conclusions Corporeal veno-occlusive dysfunction alone or combined with arterial disease is the specific hemodynamic abnormality causing nonresponse to intracavernous pharmacotherapy. Diffuse drainage, particularly involving the glans penis and corpus spongiosum, is greatly predictive of a poor or no response, reflecting the underlying cavernous smooth muscle myopathy and collagen degenerative alterations in these patients with end-organ failure.

Electromyographic Changes of Corpus Cavernosum Due to Papaverine and Nitroprusside in Veno-Occlusive Dysfunction

Purpose We compared electrical activity of the corpus cavernosum after intracavernous papaverine and nitroprusside injections. Some aspects of the androgen modulator system in patients with veno-occlusive dysfunction are discussed. Materials and Methods Electromyography of the corpus cavernosum was performed before and 1 day after intracavernous injection of 60 mg. papaverine and 400 microgram sodium nitroprusside in 22 patients with veno-occlusive dysfunction. Changes in duration and amplitude of electromyographic potentials were compared in groups with and without incoordination patterns. Results The decreases in electrical amplitude and duration in 15 patients with a negative incoordination pattern, and increases in 7 with a positive pattern were more significant with intracavernous sodium nitroprusside than with papaverine injections. Conclusions Electromyographic changes were more prominent with nitroprusside than with papaverine, which demonstrates the use of nitroprusside when performing corpus cavernosum electromyography.

Electromyographic Changes of Corpus Cavernosum Due to Papaverine and Nitroprusside in Veno-Occlusive Dysfunction

Electromyographic Changes of Corpus Cavernosum Due to Papaverine and Nitroprusside in Veno-Occlusive Dysfunction

Mechanisms of Venous Leakage: A Prospective Clinicopathological Correlation of Corporeal Function and Structure

Purpose We investigated the pathophysiology of structurally based corporeal veno-occlusive dysfunction. Materials and Methods We prospectively evaluated 24 impotent patients (mean age plus or minus standard error 46 plus/minus 3 years) who had exposure to vascular risk factors and/or disorders inducing diffuse trabecular structure alterations and who underwent penile prosthesis insertion. Preoperative indexes of veno-occlusive function (flow to maintain, venous outflow resistance and pressure decay measurements using repeat dosing pharmacocavernosometry) were correlated with postoperative erectile tissue computer assisted color histomorphometry (percent trabecular smooth muscle to total erectile tissue area). To develop further study findings and correlate histomorphometric findings with molecular biological properties molecular biological studies (ribonuclease protection analysis, reverse transcription-polymerase chain reaction assay for expression of transforming growth factor-beta 1 messenger [m] ribonucleic acid [RNA] and protein affinity labeling techniques for specific transforming growth factor-beta receptors) were performed in representative patients with high (39 to 43 percent), intermediate (30 to 37 percent) and low (13 to 29 percent) trabecular smooth muscle content (normal 42 to 50 percent). Results Flow to maintain, venous outflow resistance and pressure decay values significantly correlated with trabecular smooth muscle cell content (r = -0.89, 0.82 and -0.85, respectively). In the high, intermediate and low smooth muscle content subgroups flow to maintain, venous outflow resistance and pressure decay values were 1 to 5, 9 to 30 and 50 to 120 ml. per minute, 17 to 84, 3 to 9 and 1 to 2 mm. Hg/ml. per minute, and 40 to 60, 48 to 80 and 110 to 120 mm. Hg decrease in 30 seconds from 150 mm. Hg, respectively. There were no significant differences in patient age or prevalence of risk factors among the 3 subgroups. Patients representative of all 3 subgroups had transforming growth factor-beta 1 mRNA, auto-induction of transforming growth factor-beta 1 mRNA and induction and/or increased availability of all 3 types of transforming growth factor-beta receptors. Conclusions The pathophysiology of structurally based corporeal veno-occlusive dysfunction is related to elevated corporeal connective tissue content. Based on our data and those in the literature corporeal fibrosis is hypothesized to develop secondary to abnormalities in the regulation of normal collagen synthesis and degradation, most likely associated with adverse influences of chronic ischemia.

Multifactorial evaluation of diabetic erectile dysfunction.

We determined arterial venous and sinusoidal factors in 20 patients with insulin dependent diabetes mellitus and erectile dysfunction by performing dynamic infusion cavernosometry (DIC), colour flow Doppler ultrasonography, penile biothesiometry and corpus cavernosum electromyography (CCE). DIC, colour flow Doppler ultrasonography and penile biothesiometry were done in standard fashion except for CCE. Paradoxical increase in the electrical activity of corpus cavernosum after intracavernous (IC) papaverine was called a discoordination that was due to cavernous smooth muscle contraction instead of relaxation. Arterial and accompanying pathologies were found in 10 (50%) patients. In 3 (15%) of them pure arterial pathology, in 6 (30%) patients arterial and veno-occlusive dysfunction (VOD) and in one patient arterial pathology with abnormal biothesiometry were found. VOD and accompanying pathologies were found in 12 (60%) patients. In 6 (30%) of them VOD and arterial, in 4 (20%) patients VOD and discoordination and in 2 (10%) patients VOD and abnormal biothesiometric values were present. A higher frequency and coexistence of VOD and discoordination pattern were observed. In conclusion, patients with diabetic impotence show a wide range pathophysiology of erection and the evaluation of these patients must include multistep techniques.

O-8-4 - Antiulcer properties of some prolin-containing oligopeptides

To determine the etiology of cases with organic erectile dysfunction (ED), invasive techniques are needed that can induce patient anxiety and disturb test results.To find any special patterns of nocturnal penile tumescence and rigidity (NPTR) records in cases of vasculogenic impotence that can differentiate cases of arterial and venous origin without resorting to the more invasive diagnostic tests.This study included 95 cases of ED (77 cases with abnormal NPTR records plus 18 cases with normal NPTR). History taking and clinical examination with estimation of serum androgen hormones and postprandial blood glucose were done. All patients were then subjected to the following: NPTR monitoring using RigiScan device (Dacomed Corporation, Minneapolis, MN, USA), pharmacopenile duplex ultrasound examination, and redosing pharmacocavernosometry. According to the results of these tests, patients were classified into four groups: psychogenic, arteriogenic, venogenic, and combined arteriogenic–venogenic ED groups. Receiver operator characteristic (ROC) curve analysis of the different RigiScan parameters of venogenic group vs. the arteriogenic group was done. Best parameters were then retested by using them in prediction of veno‐occlusive dysfunction (VOD) in all studied patients.Different RigiScan parameters: number of events, duration of best episode, base tumescence, base rigidity, tip tumescence, and tip rigidity.RigiScan parameters were statistically lower in venogenic than in arteriogenic group and were more correlated with flow to maintain than the peak systolic velocity. ROC curve analysis showed that VOD can be predicted if the duration of the best event is <11.5 minutes (diagnostic accuracy 83.7%) or tip rigidity is <36.5% (diagnostic accuracy 81.6%). On generalizing these values in all patients, duration of best event showed diagnostic accuracy of 88.4%.VOD can be predicted if duration of the best event of NPTR monitoring is less than 11.5 minutes, but the presence of concomitant arterial dysfunction cannot be excluded. Elhanbly S and Elkholy A. Nocturnal penile erections: The role of RigiScan in the diagnosis of vascular erectile dysfunction. J Sex Med 2012;9:3219–3226.

O-8-2 - Therapeutic effect of yohimbine in organic and non-organic erectile dysfunction

To determine the etiology of cases with organic erectile dysfunction (ED), invasive techniques are needed that can induce patient anxiety and disturb test results.To find any special patterns of nocturnal penile tumescence and rigidity (NPTR) records in cases of vasculogenic impotence that can differentiate cases of arterial and venous origin without resorting to the more invasive diagnostic tests.This study included 95 cases of ED (77 cases with abnormal NPTR records plus 18 cases with normal NPTR). History taking and clinical examination with estimation of serum androgen hormones and postprandial blood glucose were done. All patients were then subjected to the following: NPTR monitoring using RigiScan device (Dacomed Corporation, Minneapolis, MN, USA), pharmacopenile duplex ultrasound examination, and redosing pharmacocavernosometry. According to the results of these tests, patients were classified into four groups: psychogenic, arteriogenic, venogenic, and combined arteriogenic–venogenic ED groups. Receiver operator characteristic (ROC) curve analysis of the different RigiScan parameters of venogenic group vs. the arteriogenic group was done. Best parameters were then retested by using them in prediction of veno‐occlusive dysfunction (VOD) in all studied patients.Different RigiScan parameters: number of events, duration of best episode, base tumescence, base rigidity, tip tumescence, and tip rigidity.RigiScan parameters were statistically lower in venogenic than in arteriogenic group and were more correlated with flow to maintain than the peak systolic velocity. ROC curve analysis showed that VOD can be predicted if the duration of the best event is <11.5 minutes (diagnostic accuracy 83.7%) or tip rigidity is <36.5% (diagnostic accuracy 81.6%). On generalizing these values in all patients, duration of best event showed diagnostic accuracy of 88.4%.VOD can be predicted if duration of the best event of NPTR monitoring is less than 11.5 minutes, but the presence of concomitant arterial dysfunction cannot be excluded. Elhanbly S and Elkholy A. Nocturnal penile erections: The role of RigiScan in the diagnosis of vascular erectile dysfunction. J Sex Med 2012;9:3219–3226.

Study of Etiologic Relationship of Arterial Atherosclerosis to Corporal Veno-Occlusive Dysfunction in the Rabbit

Study of Etiologic Relationship of Arterial Atherosclerosis to Corporal Veno-Occlusive Dysfunction in the Rabbit

Study of Etiologic Relationship of Arterial Atherosclerosis to Corporal Veno-Occlusive Dysfunction in the Rabbit

Purpose The aim of this study was to explore the possible etiologic relationship of hypercholesterolemia and atherosclerosis to corporal veno-occlusive dysfunction. Materials and Methods In the New Zealand White rabbit, the competence of the corporal veno-occlusive mechanism was examined at various intervals after exposure to control diet, high cholesterol diet, or aortoiliac atherosclerosis. Results Initially, all animals showed normal erectile function and corporal veno-occlusion. After 8 weeks and 16 weeks, the control animals preserved normal erection and corporal veno-occlusion, while most of the hypercholesterolemic and atherosclerotic animals developed corporal veno-occlusive dysfunction. The incidence of corporal veno-occlusive dysfunction in the hypercholesterolemia and atherosclerotic animals increased with time. Conclusions This study suggests that a close relationship exists between prolonged atherosclerotic occlusion of major penile arteries and the development of corporal veno-occlusive dysfunction. Ischemia-induced corporal veno-occlusive dysfunction may be the result of alterations in corporal smooth muscle relaxation or changes in the structure and fibroelastic properties of erectile tissue.

Penile Vascular Assessment Using Color Duplex Sonography in Men with Peyronie's Disease

Purpose We assessed penile vasculature in men with Peyronie's disease using color duplex ultrasound. Materials and Methods A total of 99 consecutive men with Peyronie's disease underwent duplex ultrasound with 60 mg. intracavernous papaverine to gain an understanding of penile vasculature and its correlation to erectile rigidity. Patients were stratified into groups according to duplex ultrasound vascular parameters and the presence or absence of impotence (that is rigidity adequate for intromission). Results Of 97 men 31 (32 percent) complained of impotence, 8 of 99 (8 percent) had evidence of corporeal veno-occlusive dysfunction on duplex ultrasound (defined as end diastolic flow velocity greater than 4.5 cm. per second) and 43 percent had a history of vascular risk factors that may have contributed to erectile insufficiency. Impotent patients had decreased peak systolic flow velocity, increased end diastolic flow velocity and a higher percent of vascular risk factors (p = 0.0006, 0.027 and 0.0004, respectively) compared to potent patients. Conclusions Duplex ultrasound provides a dynamic noninvasive functional assessment of penile vasculature in Peyronie's disease. Although corporeal veno-occlusive dysfunction has been considered the primary vascular etiology of erectile dysfunction associated with Peyronie's disease, arterial insufficiency is a major contributor, which is best detected before definitive therapy.