Prostacyclin-to-thromboxane A2 ratio in arteriogenic impotence

It has been suggested that penile hypercoagulability predisposes to aging penile vascular changes and impotence, and that elevated thromboxane A2 during erection may contribute to hypercoagulability and atherosclerosis. Since the ratio of the prostacyclin concentration to the thromboxane A2 concentration is constantly maintained in normal hemostatic responses, an imbalance between thromboxane A2 and prostacyclin may be a factor to initiate vascular diseases and decrease blood flow. We assess the usefulness of the prostacyclin-to-thromboxane A2 ratio in penile blood during erection for diagnosis of arteriogenic impotence. The ratio in the arteriogenic impotence group was significantly lower (p less than 0.01) than in the psychogenic and venogenic impotence groups. Therefore, the prostacyclin-to-thromboxane A2 ratio seems to be useful to diagnose arteriogenic impotence.     

Dual radioisotopic study: a technique for the evaluation of vasculogenic impotence.

Arterial and venous systems are the main points for the evaluation of vasculogenic impotence. To evaluate both of these systems in the same study we propose a dual radioisotopic study in which 99mtechnetium (99mTc) and 133xenon (133Xe) were used. The changes in 99mTc and 133Xe radioactivities administered intravenously and intracavernously, respectively, were monitored before and after intracavernous papaverine injection. These changes were determined as time activity curves, which were generated from the region of interest over the penis. A 99mTc penogram index derived from the 99mTc time activity curve was significantly different in the control and arteriogenic impotence groups (131.67 +/- 74.6 versus 62.94 +/- 51.6, p less than 0.01). A meaningful correlation between 99mTc penogram index results and duplex ultrasonographic findings were observed (r = 0.905). 133Xe penogram index, derived from the 133Xe washout curve was significantly different in the control and venogenic impotence groups (-25.65 +/- 24.9 versus -56.09 +/- 13.4, p less than 0.01). Also, a meaningful correlation was obtained between pharmacocavernosometry and 133Xe penogram index results of venogenic impotent patients (r = 0.86). These findings suggest that the dual radioisotopic study will be a useful technique in the evaluation of the entire vascular system of the penis, since it is a noninvasive method.     

Diagnostic tests for impotence: a comparison of papaverine injection with the penile-brachial index and nocturnal penile tumescence monitoring

The diagnostic usefulness of nocturnal penile tumescence monitoring, penile-brachial index and intracorporeal injection of papaverine (60 mg. in 20 ml. normal saline) was compared in 43 impotent men. Intracorporeal pressure was measured with a pressure transducer. Based on turgidity, and the time of onset and duration of erection, we classified the impotence as psychogenic/neurogenic (normal vascular competence), mild or severe arteriogenic, or venogenic. The intracorporeal injection of papaverine was useful as a functional diagnostic test for impotence. The penile-brachial index, an indirect measurement of the flaccid penis, did not correlate well with the results of the papaverine test. A poor response to papaverine injection documents organic impotence and, under these circumstances, nocturnal penile tumescence monitoring is not necessary. We conclude that the intracorporeal injection of papaverine currently is the best screening technique for the differential diagnosis of vasculogenic impotence.     

Functional evaluation of penile arteries with duplex ultrasound in vasodilator-induced erection

In 657 impotent patients in whom erection was induced by intracavernous injection of papaverine, we evaluated changes in the pulsation, diameter, and blood flow velocity of the penile arteries by duplex sonography and pulsed Doppler spectrum analysis. An additional 18 patients who were proved to have good erection by nocturnal tumescence testing were used as controls. All patients were studied before achieving full erection after papaverine injection. In the flaccid state, the inner diameter of the deep penile arteries averaged 0.51 mm, and blood flow velocity was rarely measurable. The normal arterial reaction to papaverine was an initial increase in the inner diameter of the scanned segment of the cavernous artery with good concentric pulsations and a mean peak blood flow velocity of 34.8 cm per second and a mean diameter of 0.89 mm. With this technique, we assessed the functional capability of each deep and dorsal artery. Arterial and erectile response allowed indirect evaluation of the venous system. Of the 657 patients, 48 had neurogenic or psychogenic impotence or both. In 97, impotence could be ascribed to venogenic causes, in 210 to arteriogenic causes, and to mixed arteriogenic and venogenic causes in 282 patients. The exact cause of impotence in the remaining 20 patients could not be determined. Statistically, patients who were older or had diabetes mellitus or coronary artery disease tended to have smaller penile arteries and lower peak blood flow velocity after papaverine injection.     

Vasculogenic impotence and cavernosal oxygen tension

AIMS OF THIS STUDY: To determine the associations, if any, of cavernosal oxygen tension with vasculogenic impotence. MATERIALS AND METHODS: We evaluated penile cavernosal blood gas levels in men with suspected vasculogenic impotence during penile duplex ultrasonography and/or dynamic infusion cavernosometry and cavernosography (DICC). Patients with suspected impotence were evaluated from 1992-1996. Patient ages ranged from 24-75 y (mean 48 y). Eighteen men had arteriogenic impotence diagnosed by abnormal penile duplex ultrasound after injection of a vasoactive agent, and 23 men had venous leakage diagnosed by DICC. RESULTS: Eighteen men with arteriogenic impotence had the following mean blood gas values: pH = 7.38+/-0.01, PCO2 = 45.50+/-0.94, PO2 = 65.17+/-2.16. Twenty-three men with venogenic (venous leak) impotence had the following mean cavernosal blood gas values: pH = 7.41+/-0.01, PCO2 = 42.26+/-0.83, PO2 = 74.17+/-2.51. The differences in PO2 were significant (P<0.05). A subgroup of men with severe venous leakage had PO2 values that were similar to the low arterial PO2 values. CONCLUSION: The low PO2 in patients with arteriogenic impotence, and the subset of men with severe venous leak impotence, support a global concept of low cavernosal PO2 as a mechanism for both arteriogenic and venogenic impotence.     

Role of RigiScan parameters in differentiation of vascular erectile dysfunction

Male nocturnal penile tumescence and rigidity assessed by RigiScan monitoring device (GOTOP Inc.) is a noninvasive tool to differentiate organic from psychogenic erectile dysfunction (ED). This study aimed to determine the diagnostic value of RigiScan parameters in differentiating arterial ED from veno-occlusive ED. We recruited 102 male patients (mean ± SD, 32.3 ± 6.7 years old) presented with an overall score <21 in the 5-item version of the International Index of Erectile Function scoring system. Baseline data of the included subjects were collected, and the patients were then subjected to RigiScan monitoring, penile colour Doppler ultrasound, and dynamic infusion cavernosometry and cavernosography examination. These patients were allocated into psychogenic, arterial and venous ED group based on the results of these specific examinations. At last, psychogenic ED was identified in 56 out of 102 men, while arteriogenic ED was identified in 31 cases and venogenic ED in 15 out of the overall 102 cases. The erection episodes per night (1.6 ± 0.5 vs. 2.5 ± 0.9 for venogenic vs. arterial ED respectively) and the duration of tip erections ≥60% in the venogenic ED group (21.5 ± 10.5 min) were significantly lower than cases in arteriogenic ED individuals (34.5 ± 17.0 min). Besides, receiver operating characteristic analysis showed that the duration of tip erections with a cut-off value of 12.5 min had 81.4% sensitivity and 100% specificity for predicting a venogenic ED in cases with organic impotence. In conclusion, the duration of tip erection of RigiScan parameters was used to distinguish venogenic from arterial ED.     

Electrocavernosogram in erectile dysfunction: a diagnostic tool

Corpora cavernosa (CC) evoke electric waves that appear to be of diagnostic significance in evaluation of erectile dysfunction (ED). We investigated the hypothesis that electrocavernosography (ECG) exhibits different patterns in the various types of ED: neurogenic, vasculogenic, and psychogenic. Electrocavernosography was performed in the flaccid phase in 16 neurogenic, 28 vasculogenic (15 arteriogenic, 13 venogenic), and 24 psychogenic patients with ED, and in 15 healthy volunteers (controls). Two needle electrodes were introduced into the CC and the EMG activity was recorded in each of the 2 CCs of the same subject. Two 20 minute recording sessions were performed for each subject. The controls recorded slow waves (SWs) with regular rhythm and identical frequency, amplitude and conduction velocity from the 2 electrodes of the same subject. Random action potentials (APs) were superimposed on or followed the SWs. The ECG in the neurogenic ED recorded no waves in 14/16 patients and occasional irregular waves in 2. The SWs of the arteriogenic ED had irregular rhythm and variable and low parameters compared to those of the controls. The ECG of the patients with venogenic ED was similar to that of the controls, while the ECG of the psychogenic ED exhibited SWs with irregular rhythm and higher parameters than the controls. The study has revealed various ECG patterns in ED: "silent" in neurogenic. "bradyarrhythmic" in arteriogenic, "normal" in venogenic, and "overactive" in psychogenic ED. We suggest that electrocavernosography has the potential to function as an investigative tool in diagnosing the type of ED provided further studies are performed to verify the described findings.     

VISER检查鉴别心理性与器质性勃起功能障碍(附320例报告)

目的应用VISER鉴别心理性与器质性ED并利用该方法对心理性ED严重性进行客观分级。方法320例ED患者接受了VISER检查。首先海绵体内注射罂粟硷10mg；未诱发勃起，药物剂量增至30mg。将药物试验阳性者定义为心理性ED，并根据海绵体压力、波幅形态以及药物剂量将心理性ED分为轻、中、重二度。两次检查均失败者，行阴茎彩色多普勒超声和海绵体造影检查。结果本组中，心理性ED占81．9％，其中轻度、中度和重度者分别占19．8％，60．7％和19．5％。在部分病例中，检查结果与Zung氏抑郁量表评分具有一定相关性。33例接受阴茎多普勒超声或海绵体造影检查提示，正常13例，动脉性ED5例，静脉性ED9例，动脉静脉混合性ED6例。结论VISER有助于签别心理性与器质性ED，依据其结果对心理性ED严重程度进行客观分级，便于对患者选择有针对性的治疗。     

Penile venous drainage in erectile dysfunction. Anatomical, radiological and functional considerations

To elucidate further the penile venous anatomy and its role in the haemodynamics of erection, we performed pharmacological cavernometry and cavernography in 95 patients with venogenic impotence and in 12 patients with psychogenic impotence. The findings were correlated with those of dissection in 10 adult male cadavers. Cavernography confirmed that the main venous drainage of the corpora cavernosa is via the cavernous veins, with additional drainage through the crural, circumflex and deep dorsal veins and demonstrated that, in patients with venogenic impotence, the cavernous veins are the common site of leakage. Cavernometry provided valuable parameters for the quantification of the degree of venous leakage. Detailed knowledge of the penile venous system and cavernometry and cavernography are essential for the proper diagnosis and treatment of patients with venogenic impotence.     

Nocturnal penile tumescence predicting response to intracorporeal pharmacological erection testing

Although response to intracorporeal pharmacological erection testing has been proposed to determine the etiology of impotence, physiological criteria predicting this response have not been established and the literature includes conflicting results regarding which patients respond to pharmacological erection therapy. In this study 37 impotent patients underwent a diagnostic nocturnal penile tumescence evaluation (including measurements of rigidity, pulsations and bulboischiocavernosus muscle activity) and the results were correlated with subsequent response to intracorporeal pharmacological testing. Most but not all patients with psychogenic impotence and all with neurogenic impotence responded with good erections. For vasculogenic impotence response rate depended upon impairment severity determined from nocturnal penile tumescence measurements; none of the severe cases versus 90 per cent of the milder cases responded. The results indicate that response to intracorporeal pharmacological testing does not accurately distinguish psychogenic from organic impotence, is best for neurogenic impotence and worst for severe vasculogenic impotence, and can be predicted accurately by nocturnal penile tumescence measurements.     

Gravity cavernosometry--a simple diagnostic test for cavernosal incompetence

The papaverine test has been widely used as a diagnostic procedure in erectile impotence. However, when patients do not achieve full erection on the test, it is necessary to differentiate between insufficient inflow and excessive outflow. Gravity cavernosometry is a method designed to evaluate the pressure responses in the corpora when they are subjected to a constant infusion pressure. The infusion flow is of minor significance. The intracavernous pressure (ICP) was measured in cadavers, in psychogenically impotent patients and in patients with arteriogenic impotence, following administration of papaverine and gravity perfusion. During perfusion in cadavers and in psychogenic patients, the ICP showed values above 110 cm H2O, while in arteriogenic patients the values ranged from 30 to 141 cm H2O. In the arteriogenic group, 11/20 patients had an ICP lower than 110 during perfusion. There was no correlation between the pre-perfusion pressure and the final pressure with perfusion. Gravity cavernosometry is a simple, cost-effective and reliable method for the assessment of corporeal competence.     

Radioisotope penogram in diagnosis of vasculogenic impotence

A radioisotope technique to estimate penile blood flow is described. The radioisotope penogram is noninvasive and gives a dynamic evaluation of the arterial supply, venous drainage, and blood flow in the corporeal bodies. The penogram is a valuable adjunct in evaluation of patients with vasculogenic impotence.     

Noninvasive vacuum constriction device in the management of erectile dysfunction

The effectiveness of a device designed to overcome erectile impotence was assessed in 21 patients: 5 patients with vasculogenic impotence due to venous leakage, 6 with diabetes mellitus with or without atherosclerotic cardiovascular disease, 2 paraplegic patients after spinal cord injury, 3 severely obese patients and 5 patients with psychogenic impotence. They were instructed how to use the device, which uses suction to induce penile engorgement and maintains erection with a constriction band. A total of 17 patients (81%) achieved an erection or an erection-like state that was satisfactory for intercourse. No serious ill effect from the use of the device has been reported. In selected patients the device is an alternative to either surgical placement of penile prosthesis, intracavernous injection of vasoactive drugs or sexual abstinence.     

Comparative value of prostaglandin E1 and papaverine in treatment of erectile failure: double-blind crossover study among Egyptian patients.

In a double-blind, crossover designation penile intracavernous prostaglandin E1 and papaverine hydrochloride were compared in regard to effectiveness and safety in 52 patients investigated and treated for sexual erectile dysfunction. In evidence of the reliable effectiveness, prostaglandin E1 (20 micrograms/ml.) induced significant positive erectile response in 42 of 52 patients (81%). This rate reached 100% with neurogenic, hyperprolactinemic and/or psychogenic impotence. However, with papaverine hydrochloride (30 mg./ml.) and exclusively in cases of vasculogenic (most probably arteriogenic) impotence, negative erectile response was revealed as absent erection in 6 of 52 patients (11.5%) and nonrigid tumescence in 13 (25%) versus 2 (3.8%) and 8 (15.4%), respectively, with prostaglandin E1. Moreover, with prostaglandin E1 the regional pain was tolerable and transient, and the positive erectile response was not attended by priapism even in patients who formerly had priapism with papaverine hydrochloride. However, presently with prostaglandin E1 the relatively higher cost and shorter expiration period would probably limit its diagnostic and therapeutic use in Egypt, and probably in other developing countries.     

Erotic erection versus nocturnal erection

To clarify the correlation between erotic and nocturnal erections, and to evaluate the diagnostic efficacy of the audiovisual stimulation penogram as an initial screening test for impotent patients, a comparative study of 137 impotent patients was designed. The audiovisual stimulation penogram shows dynamic penile blood flow change during audiovisual stimulation using a radioisotope (99mtechnetium) and is classified as type 1--similar findings to normal volunteers, type 2A--impossible erection due to insufficient blood flow, type 2B--unstable erection due to severe fluctuation in blood flow and type 2C--delayed erection. The compatibility ratios of the audiovisual stimulation penogram types 1, 2A and 2C with some tests for nocturnal erection were relatively high (63 to 80%) and when compared to the final diagnosis all but 1 of the compatible cases with nocturnal erection studies were able to be diagnosed correctly. However, the compatibility ratio of the audiovisual stimulation penogram type 2B was markedly low (35%) and this group had complicated etiologies, including many more psychogenic than organic causes. Although the mechanisms of the erotic and nocturnal erections have not been fully elucidated to date, our results suggest that the audiovisual stimulation penogram seems to be an appropriate initial screening step if we refine the criteria for type 2B, and a comprehensive interpretation of the tests for erotic and nocturnal erections will result in a more accurate diagnosis.     

静脉性勃起功能障碍中阴茎静脉漏的彩色多普勒超声观察

目的 探讨静脉性勃起功能障碍(ED)患者阴茎静脉的血液动力学变化. 方法 静脉性ED患者32例,年龄26～63岁,平均41岁.病程6个月～10年,平均2.5年.采用前列腺素E1试验后行常规阴茎彩色多普勒超声检查,观察阴茎背深静脉、海绵体静脉、球静脉的超声表现,分析其与海绵体动脉阻力指数(RI)的相关性. 结果 32例患者诱发勃起前静脉内径(0.06±0.15)mm,血流速度(4.30+1.36)cm/s,诱发勃起5 min后阴茎静脉管径(1.23±0.30)mm,血液回流增多,血流速度(11.50+4.02)cm/s.阴茎背深静脉、海绵体静脉、球静脉流量与海绵体动脉RI的相关系数r分别为-0.55,-0.53,-0.24(P＜0.05).考虑存在混合性静脉漏因素的前提下,阴茎静脉流量与海绵体动脉RI的r为-0.88(P＜0.001). 结论 高频超声能清楚显示阴茎静脉漏部位,可初步判断静脉性ED患者的静脉漏部位及其程度.     

High-flow priapism and glans hypervascularization following deep dorsal vein arterialization for vasculogenic impotence.

Microsurgical penile revascularization is becoming an increasingly applied technique in patients with arteriogenic or mixed arteriogenic and venogenic impotence. Deep dorsal vein arterialization has been used successfully in selected patients. Aside from failure of the procedure and the occasional problems associated with vascular surgery, priapism and glans hypervascularization are specific complications of deep dorsal vein arterialization. Priapism in these cases is 'high-flow'; the functional arterial-cavernous fistula can overcome the maintenance of the flaccid state and cause persistent erection. Glans hypervascularization, a syndrome of glans enlargement, skin changes and pain secondary to excessive retrograde filling of the glans penis and corpus spongiosum, can result in urethral compression and glans ulceration. Along with the presentation of the case of a man who suffered both complications, we discuss their pathophysiology, prevention, and treatment.     

Can an intracavernous papaverine injection be used to diagnose arteriogenic impotence?

We injected papaverine into the corpus cavernosum of 93 patients with impotence, and compared the results with findings from nocturnal penile tumescence monitoring, psychogenic erection monitoring after sexual stimulation, penile-brachial indexes, and dynamic cavernosography. There was a significant correlation between the findings from papaverine injection and dynamic cavernosography, but there was no correlation between the papaverine findings and other tests including the penile-brachial index. We conclude that we can disregard the possibility of venous abnormality in those who respond to papaverine injection, but we cannot disregard the possibility of arteriogenic abnormality. We proved that papaverine injection cannot diagnose arteriogenic abnormality.     

Pharmacocavernometry: a modified papaverine test

The papaverine test has become established in the investigation of impotence. Although a full response to papaverine excludes a significant vascular lesion, failure to respond may be due to either arterial deficiency or venous leakage. Pharmacocavernometry, which combines the papaverine test and an artificial erection test, was performed in 126 patients. Intracorporeal pressure was monitored following the intracorporeal injection of 80 mg papaverine; 10 min later, saline was infused to determine the presence of a venous leak. Five different responses were observed. Patients with a Type 1 or 2 response were psychogenic or neurogenic. Patients with a Type 3 response were arteriogenic and patients with a Type 4 or 5 response had significant venous leakage. The modified papaverine test permits more information to be gained concerning the aetiology of the impotence.     

Double-blind, cross-over study comparing prostaglandin E1 and papaverine in patients with vasculogenic impotence

Intracorporeal injection of vasoactive agents is the treatment of choice for many patients with organic impotence. However, some patients with vasculogenic impotence respond poorly to injections of papaverine or papaverine/phentolamine. This study was conducted to determine if patients with vasculogenic impotence who failed to respond to papaverine might respond to prostaglandin E1 and thus be salvaged from possible prosthetic surgery. A total of 54 patients with vasculogenic impotence were administered intracorporeal prostaglandin E1 (20 micrograms) and intracorporeal papaverine (60 mg) randomized in a double-blind fashion and crossed over one week later. Forty-six percent of patients receiving prostaglandin E1 produced a satisfactory erection compared with 14 percent of patients with a similar response to papaverine. The difference between these results was highly significantly by the McNemar test. The number of side effects were similar for both drugs. Prostaglandin E1 might be considered the intracorporeal agent of choice for patients with significant vasculogenic impotence.