High resolution ultrasonography and pulsed wave Doppler for detection of corporovenous incompetence in erectile dysfunction

The role of computerized tomography angiography in the management of cases undergoing penile revascularization due to erectile dysfunction: prospective cohort study

BACKGROUND

In this study, the role and efficiency of computerized tomography angiography (CTA) in the postoperative management of patients with penile revascularization were evaluated.

METHODS

Between 2014 and 2018, penile revascularization surgery was performed in 78 patients who presented with the complaint of erectile dysfunction (ED). The mean age of the patients was 47.17 ± 13.26 (23-69) years. Patients with a regular sexual partner and relationship, who hadn't benefitted from medical treatment and who had ED complaints for at least three months were included in the study. The cases were divided into three groups according to their age (20-40, 41-60, and > 61 years). All the cases were evaluated preoperatively using the five and 15-item International Index of Erectile Dsysfunction (IIEF-5 and IIEF-15) questionnaire, cavernosometry, corpus cavernosum electromyography, and penil color doppler ultrasonography. At the postoperative third month, IIEF 5-15 questionnaire was repeated and anastomotic patency was evaluated by performing CTA scanning.

RESULTS

CTA performed at the postoperative third month revealed anastomosis patency in 56. In 22 cases, the anastomosis area could not be observed. Among the patients with anastomosis patency, the rate of the IIEF-5 increase in the postoperative period was between 35.0 and 80.8%, while in those patients without anostomotic patency, the increase rate of IIEF-5 were between 12.5 and 23.3%. Increases in the IIEF-5 and IIEF-15 questionnaire scores were found to be significantly higher in the group in which anastomotic patency was observed on CTA compared to remaining patients.

CONCLUSION

The CTA results and changes in the IIEF rates after penile revascularization had a high correlation. Anastomotic patency with CTA can guide the timing of more invasive procedures such as penile prosthesis implantation.

Duplex Doppler Scanning with Prostaglandin E1 in the Diagnosis of Cavernovenous Leakage

The aim of this study was to find out the normal response of the duplex Doppler (DD) parameter resistance index (RI) during a high dose prostaglandin E1 (40μg) induced erection and to evaluate the clinical usefulness of DD scanning in the diagnosis of cavernovenous leakage (CVL). The results of DD scanning and cavernometry were compared in 10 potent control subjects and 82 impotent patients. RI was ≥ 1 in all control subjects later than 10 min after the intracavernous injection and RI at 20 min after the injection (RI20) was chosen as a clinical parameter. An inverse correlation (r = −0.69, p < 0.001) between RI20 and the maintenance flow (MF) at 150 mm Hg (MF150) was demonstrated. Sensitivity and specificity of RI20 (values <1 indicating CVL) as a test of CVL (MF150 > 18 ml/min) were 89% and 86%, respectively. In conclusion, the measurement of RI20 in DD scanning after an adequate pharmaco-stimulation is a reliable, noninvasive method in the diagnosis of CVL.

Evaluation of penile rigidity with color Doppler flow imaging in Chinese patients with erectile dysfunction

OBJECTIVES

To assess the role of color Doppler flow imaging (CDFI) in the evaluation of Chinese patients with erectile dysfunction (ED) and to explore the association between penile rigidity and hemodynamic parameters of CDFI.

METHODS

Totally 74 ED patients with an age range of 22-69 (median age 47) were included in our study, hemodynamic parameters including the peak systolic velocity (PSV), end-diastolic velocity (EDV) and resistance index (RI) of the penile cavernous artery were measured by CDFI before and after intracavernous pharmacological testing. The degree of penile rigidity was classified according to Schramek grading system. The correlation between the penile rigidity state and its hemodynamic parameters was analyzed.

RESULTS

In ED patients, the abnormalities of cavernous artery and dorsal vein could be evaluated by the value of PSV and EDV with combination of penile rigidity. Among different penile rigidity status, the PSV, EDV and RI of the cavernous artery were significantly different (p < 0.05). The RI correlated significantly with the penile rigidity (r(2) = 0.7948).

CONCLUSION

The CDFI hemodynamics of the penile cavernous artery are helpful in the etiological diagnosis of Chinese ED patients and can be used as one of the quantitative indexes for penile rigidity, which is consistent with western guidelines.

A Mathematical Model of Penile Vascular Dysfunction and Its Application to a New Diagnostic Technique

A noninvasive diagnostic device was developed to assess the vascular origin and severity of penile dysfunction. It was designed and studied using both a mathematical model of penile hemodynamics and preliminary experiments on healthy young volunteers. The device is based on the application of an external pressure (or vacuum) perturbation to the penis following the induction of erection. The rate of volume change while the penis returns to its natural condition is measured using a noninvasive system that includes a volume measurement mechanism that has very low friction, thereby not affecting the measured system. The rate of volume change (net flow) is obtained and analyzed. Simulations using a mathematical model show that the device is capable of differentiating between arterial insufficiency and venous leak and indicate the severity of each. In preliminary measurements on young healthy volunteers, the feasibility of the measurement has been demonstrated. More studies are required to confirm the diagnostic value of the measurements.

Ultrasound evaluation of the penis for assessment of impotence

Image directed Doppler ultrasonography of the cavernous arteries provides functional, quantifiable assessment of penile arterial flow during a pharmacological erection. In this respect, this modality is superior to arteriography as a means of evaluating arteriogenic impotence. Peak flow velocity, arterial dilatation, and vessel pulsation are the most reliable ultrasonic indicators of arterial health. Aberrant arterial anatomy should be noted as this may contribute significantly to total penile blood flow. A thorough understanding of erectile physiology and anatomy is necessary to properly perform and interpret Doppler ultrasound results.

Erectile dysfunction: timing of spectral wave-form analysis in the assessment of the function of the cavernosal arteries

Color Doppler ultrasound seems to be an accurate method to evaluate vascular erectile function, in particular the arterial supply of the penis. Because of its relative noninvasiveness and easy performance, it has to precede more invasive evaluation (cavernosography and invasive angiography). Combination of wave form pattern analysis with peak systolic velocity measurements allows differentiation between arterial and venous insufficiency. Fifty-one patients suffering from erectile dysfunction, were examined with use of color Doppler ultrasound. Nine had adequate vascular function with good penile tumescence. However, during these adequate (late) stages of tumescence, peak systolic velocity fluctuated significantly. We conclude that in the late stages of tumescence, velocity measurements are not reliable as a parameter of arterial function.

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.