Potentiation of drug-induced erection with audiovisual sexual stimulation

Cavernous artery intima-media thickness predicts the response to sildenafil in erectile dysfunction patients as a morphological parameter

While the intima-media thickness (IMT) of the cavernous artery was used for diagnosis for vascular erectile dysfunction (ED) with more accuracy than the peak systolic velocity, the role of the IMT in predicting treatment responses remained unexamined. A total of 136 patients with ED were enrolled. The baseline clinical and laboratory characteristics were collected. Penile Doppler ultrasonography (PDU) was performed on all patients by a blinded sonographer. Sildenafil was administrated to all patients with an adjusted dose of 50 or 100 mg on demand over a period of 3 months. A follow-up was conducted on all patients using the Erectile Hardness Score (EHS) questionnaire along with the visual and tactile version of the standardised EHS tool. The peak systolic velocity (PSV) and IMT were compared between sildenafil responders and sildenafil nonresponders, while receiver operator characteristic (ROC) curves were used to calculate the cut-off values and compare the test power respectively. There was no statistical difference from the baseline characteristics. The IMT of cavernous artery was more accurate than PSV to predict the sildenafil response (AUC = 0.809, 0.626 respectively). IMT could predict sildenafil responders more accurately than PSV, and the cut-off value of the IMT of the cavernous artery was less than 0.22 mm.

Current approaches to the diagnosis of vascular erectile dysfunction

Vascular erectile dysfunction (ED) is closely related to cardiovascular events, and early diagnosis of vascular ED may be helpful to predict the occurrence of cardiovascular events and improve prognosis. At present, there are many approaches to diagnose ED, but each method has its advantages and limitations. This study retrospectively reviewed all available literature focusing on the diagnosis of vascular ED through a systematic PubMed and EMBASE search. According to the different application scenarios, the main methods for the diagnosis of vascular ED are divided into four categories. Intra-cavernous injection of vasoactive drugs is the earliest method used in the diagnosis of vascular ED and is a basic test. For the diagnosis of arterial ED, color duplex Doppler ultrasound, selective penile angiography, magnetic resonance imaging, and computed tomography are more commonly used. While for the diagnosis of venous ED, shear wave elastography, dynamic infusion cavernosometry and cavernosography are more accurate. Endo-peripheral arterial tonometry (PAT) has also been used to detect vascular endothelial function. Although various existing examinations are widely used for the evaluation of vascular ED, they still have some shortcomings, such as invasiveness, contingency, high false positive (negative) rate. New methods of long-term dynamic detection are needed.

Investigation of erectile dysfunction

Erectile dysfunction (ED) represents a common and debilitating condition with a wide range of organic and non-organic causes. Physical aetiologies can be divided into disorders affecting arterial inflow, the venous occlusion mechanism or the penile structure itself. Various imaging modalities can be utilised to investigate the physical causes of ED, but penile Doppler sonography (PDS) is the most informative technique, indicated in those patients with ED who do not respond to oral pharmacological agents (e.g. phosphodiesterase type 5 inhibitors). This review will examine the anatomical and physiological basis of penile erection, the method for performing PDS and features of specific causes of ED, and will also consider the alternative imaging modalities available.

Feasability of a novel audio-video sexual stimulation system: an adjunct to the use of penile duplex Doppler ultrasonography for the investigation of erectile dysfunction

INTRODUCTION

Penile color Doppler ultrasonography (CDUS) with pharmacotesting has become an important tool for evaluating vascular erectile dysfunction (ED), and audio-visual sexual stimulation (AVSS) has been suggested to be helpful in assisting the performance of CDUS during the examination.

AIM

To investigate the feasibility of using a novel, remotely controllable AVSS system to assist CDUS.

METHODS

This prospective randomized cross-over study recruited 60 consecutive ED patients. Each patient received three randomized sessions of CDUS under different conditions-AVSS, intracavernous injection (ICI) of alprostadil 20 microgram, or AVSS plus ICI. Clinical responses (rigidity) and penile vascular parameters including peak systolic velocity (PSV), end diastolic velocity (EDV), and resistive index (RI) were measured. At the end of the study, patients were asked about how they perceived the AVSS system in generating sexual arousal.

MAIN OUTCOME MEASURES

PSV, EDV, RI, and rigidity.

RESULTS

Fifty-eight ED patients (aged 21-79) underwent 174 sessions of CDUS. The mean PSV and maximal rigidity of patients under ICI alone were significantly greater than those of patients under AVSS alone (48.25 ± 22.78 vs. 36.54 ± 23.25 cm/second and 65.00 ± 23.93% vs. 43.28 ± 31.79%, respectively; both P < 0.05). The mean PSV of patients under AVSS plus ICI (55.38 ± 28.81 cm/second) was significantly greater than that of patients under ICI alone (P < 0.05), while the mean maximal rigidity (72.50 ± 22.03%) was only marginally greater (P = 0.082). EDV or RI was of no significant difference among the different conditions. Ultrasonographic diagnoses of ED under different conditions varied substantially. Fifty-four (93%) patients considered the AVSS system "very satisfactory" or "satisfactory" in evoking sexual arousal.

CONCLUSIONS

The novel, remotely controllable AVSS system is well accepted by patients and, in conjunction with ICI, helps to produce higher PSV for patients undergoing CDUS.

Evaluation of the effectiveness of sildenafil using questionnaire methods versus audio-visual sexual stimulation

AIM

In the present study, an audio-visual sexual stimulation (AVSS) test was used to evaluate the effectiveness of sildenafil, and the AVSS test was coevaluated with the international index of erectile function (IIEF) questionnaire.

METHODS

Forty-two patients with erectile dysfunction (ED) were examined (age range, 28-73 years; mean, 51.9 +/- 11.4 years). Each patient answered the IIEF questionnaire and underwent laboratory tests and the AVSS test before administration of sildenafil. The IIEF questionnaire and AVSS test (1 h after administration of 25 mg or 50 mg sildenafil) were re-evaluated in the outpatient clinic 4 weeks later. Questions 3 and 4 of the IIEF test were used to evaluate the effectiveness of sildenafil. Sildenafil was determined to be effective if each score totalled four or five after administration.

RESULTS

The rate of effectiveness of sildenafil was 52.4%, and the mean score of the IIEF 5 improved from 7.2 to 15.4 following treatment with sildenafil. The maximum and mean rigidity of the penile tip improved after the sildenafil treatment (36.1%vs 57.7% and 14.2%vs 35.8%, respectively). The maximum and mean rigidity of the penile base rose (42.4%vs 57.7% and 17.9%vs 36.8, respectively). Similarly, following treatment with sildenafil, the penile tumescence increased from 6.6 cm to 7.6 cm at the penile tip and from 7.5 cm to 8.5 cm at the penile base.

CONCLUSIONS

In some ED patients the results of the IIEF questionnaire are not always consistent with those of objective evaluation, including AVSS. In these patients, combined assessment using the IIEF and AVSS might be more useful to evaluate the precise effectiveness of sildenafil, rather than relying on the IIEF results alone.

Measurement of intracavernosal catecholamine during a prostaglandin E1 test

Background : Erectile dysfunction (ED) can be a cause of male infertility among young men. The prostaglandin E₁ (PGE₁) intracavernous injection test, an erectile function test, is known as an objective method of examining the penile vasculature system. However, some ED patients fail to sufficiently maintain an erection because of the stress load upon them during the test. Thus, we measured changes in catecholamine levels by stress loading when we performed dynamic infusion cavernosometry (DIC). Methods : Among the 221 ED patients undergoing a PGE₁ test, 10 were selected as the subjects for the present study. These 10 patients were 25-56 years of age, with a mean of 32.8 years, whose maximal penile rigidity was normal, but in whom penile erection could not be maintained sufficiently in the PGE₁ test. Stress loading via vibratory sensory measurement during the PGE₁ test suppressed penile rigidity strongly. Catecholamine levels were measured by using blood samples obtained from the corpus cavernosum and the cubital vein when erection was suppressed by stress loading, pain caused by needle insertion, and also when erection recovered from the suppression. Dynamic infusion cavernosometry was performed after each blood sampling time, to check corporeal veno-occlusive function and cavernosal arterial flow. Results : Penile norepinephrine levels were 0.20 ± 0.06 ng/mL during a suppressed erection and 0.15 ± 0.03 ng/mL during an erection, showing a significantly higher level (Student's t-test, P = 0.0309) during suppressed erection. The results of the DIC measurement indicated a normal corporeal veno-occlusive function and cavernosal artery in all cases. Conclusion : The results of the present study revealed that corporeal veno-occlusive function and cavernosal arterial flow are normal in men who have normal maximum penile rigidity, but cannot sufficiently maintain the erection in the PGE₁ test, suggesting the involvement of stress-induced penile norepinephrine in the suppression of erection maintenance. (Reprod Med Biol 2002; 1: 11-15).

Efficacy of virtual glasses in audio-visual sexual stimulation during penile color duplex Doppler ultrasonography

OBJECTIVE

To examine whether audio-visual sexual stimulation (AVSS) with virtual glasses is effective in improving the recording of penile hemodynamics during penile color duplex Doppler ultrasonography.

PATIENTS AND METHODS

A total of 64 consecutive patients with erectile dysfunction underwent penile color duplex Doppler ultrasonography after intracavernosal injection of 10-20 microg prostaglandin El and subsequent genital stimulation. AVSS with virtual glasses and earphones was applied when peak systolic velocities (PSV) were less than 35 cm/s or end diastolic velocities (EDV) were more than 5 cm/s. PSV, EDV and the resistive index of both cavernosal arteries were continuously monitored. Clinical erectile response was assessed with visual inspection and manual palpation.

RESULTS

AVSS with virtual glasses was performed on 40 of 64 patients. AVSS improved the clinical erectile response in 26 (65%) of 40 patients. Doppler ultrasonography without AVSS identified 11 (27.5%), 5 (12.5%), and 24 (60%) patients with arteriogenic, veno-occlusive, and mixed-type impotence, respectively. However, after real-time AVSS 15 (37.5%), 7 (17.5%), 8 (20%), and 10 (25%) patients demonstrated non-vasculogenic, arteriogenic, veno-occlusive, and mixed-type impotence, respectively. Real-time AVSS improved the Doppler wave forms in 65% of cases.

CONCLUSION

AVSS with virtual glasses improves the recording of physiologic erectile response and may be used as a valuable tool during penile color duplex Doppler ultrasonography.

Does vibration offer any advantage over visual stimulation studies (VSS) in the assessment of erectile capacity?

The purpose of this work was to determine whether vibration stimulation or erotic videotape material can provide an acceptable diagnostic yield for patients with erectile dysfunction (ED) without the patient needing to endure more explicit erotic films, which may be distasteful to some patients, or intracavernous injections, to which there may be a high inhibitory response. Ninety-five subjects were randomly exposed to either vibration or videotape alone and erectile response monitored by the RigiScan. Where no clinical response was recorded by the RigiScan or by self-report by the patient, both stimuli were presented to the subject. Forty-nine subjects received vibration first and 46 received videotape first. Use of clinically based standardised measures revealed neither group achieving above threshold responses to the first stimulation and there were no differences between the two groups. Eight subjects (8%) between both groups exceeded the tip threshold during combination stimulation. Single stimulation with vibration or erotic videotape with provocative RigiScan monitoring is unhelpful in the assessment of ED in any of the diagnostic subgroups of ED. In comparison to previous provocative studies, combination of stimuli sets, whilst increasing penile response (circumferential change and rigidity) did not lead to significant evidence of clinically relevant responses using current RigiScan measures or patient self-report of change. Further studies are necessary to determine the most useful set of stimuli for provocation studies with the RigiScan.

Improving the accuracy of vascular testing in impotent men: correcting hemodynamic alterations using a vasoactive medication re-dosing schedule

PURPOSE

Arteriogenic or venogenic vascular insufficiency is the most common pathophysiology of organic erectile dysfunction. While vascular insufficiency may be suspected on history and physical examination, the definitive diagnosis is made by vascular testing. Dynamic infusion cavernosometry is a recognized technique for evaluating the hemodynamics of erection. Assigning the correct vascular diagnosis during testing is important. Complete corporeal smooth muscle relaxation is essential for obtaining accurate data. Previously others have suggested that repeat dosing with vasoactive medication may improve the diagnostic accuracy of vascular testing. We investigated the hemodynamic effect of repeat doses of medication.

MATERIALS AND METHODS

Data were prospectively obtained on men undergoing dynamic infusion cavernosometry. When veno-occlusive parameters were abnormal, the intracavernous vasoactive agent dose was repeated to a maximum of 3 doses. Standard dynamic infusion cavernosometry criteria were used for diagnosing arteriogenic and venogenic erectile dysfunction. We analyzed the proportion of men in whom the vascular diagnosis was altered using this regimen.

RESULTS

Of 420 men undergoing dynamic infusion cavernosometry, 70% warranted re-dosing based on abnormal veno-occlusive parameters. Of these 294 men veno-occlusive values were corrected by repeat medication in 32% and, therefore, they would have been falsely diagnosed with venous leakage during vascular evaluation. Half of all corrections occurred with the second dose, while half of the patients required a third dose of medication.

CONCLUSIONS

These data should encourage clinicians to consider re-dosing during the vascular evaluation of men in whom incomplete corporeal smooth muscle relaxation is suspected. In this way a false diagnosis of venous leakage may be avoided in a significant number of cases.

The importance of visual erotic stimulation in the differential diagnosis of erectile impotence

In this study we aimed to determine the importance of visual erotic stimulation (VES) alone, and in combination with intracavernosal papaverine injection (ICPE) in the differential diagnosis of erectile impotence. Sixty-four patients with erection problems were investigated between June 1992 and January 1994. VES could be the first investigative method in the differential diagnosis of erectile impotence. This will help us in some groups of patients with psychogenic impotence to avoid the application and complications of ICPE. In patients with insufficient erections with VES alone, ICPE must be combined with VES in order to detect the causes of psychogenic erectile impotence more correctly.

Comparison of results of nocturnal penile tumescence and rigidity in a sleep laboratory versus a portable home monitor

OBJECTIVES

To validate the results of the home penile tumescence monitor versus the sleep laboratory studies of erectile function.

METHODS

We used both methods to study 18 episodes of rigidity and 19 episodes of tumescence in 10 subjects with erectile dysfunction before and after the use of an experimental vasodilating medication.

RESULTS

The tumescence measurement in the sleep laboratory compared favorably with the changes in tumescence with the RigiScan portable home monitor: at the base (r = 0.70; P < 0.001), and at the tip (r = 0.84; P < 0.001). In measuring rigidity, the buckling pressure in the sleep laboratory compared favorably with the RigiScan measurements of percent average rigidity at the base (r = 0.56; P = 0.017), at the tip (r = 0.62; P = 0.006), and mean rigidity of the base and tip (r = 0.64; P = 0.004). In a comparison of the buckling pressure with the new RigiScan Plus quantitative program, there was good correlation with the rigidity activity units at the base (r = 0.70; P = 0.001) and at the tip (r = 0.72; P < 0.001). A clinical estimate of penetrable rigidity correlates with the RigiScan base rigidity of 55% to 60% and tip rigidity of about 50%.

CONCLUSIONS

The portable home monitor is a viable and cost-effective clinical tool to measure nocturnal penile activity.

Effect of multidose intracorporeal injection and audiovisual sexual stimulation in vasculogenic impotence

Erections are inhibited by sympathetic stimulation. Anxiety or psychologic inhibition may produce abnormal response during impotence workup. The use of intracorporeal alpha blockers (phentolamine) and audiovisual sexual stimulation (AVSS) has been used to decrease sympathetic outflow and enhance erectile response. Thirty-three patients with suspected vasculogenic impotence were studied. They underwent pulsed Doppler ultrasound (PDUS) with multiple doses of tri-mix (mix of papaverine, phentolamine, and prostaglandin E1). AVSS was applied after maximal response to tri-mix. Seventeen patients (51.5%) responded to multidose with grade IV or V erection. When AVSS was started, 5 more patients responded, and 7 upgraded to grade V with overall response of 40 percent. AVSS can augment the in-office response to pharmacologic testing above that obtained by "maximal" pharmacologic dosing, thereby increasing the sensitivity and specificity of the test.