Hemodynamics of Erection in the Monkey

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 andaor 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 AE 0.01, PCO2 45.50 AE 0.94, PO2 65.17 AE 2.16. Twenty-three men with venogenic (venous leak) impotence had the following mean cavernosal blood gas values: pH 7.41 AE 0.01, PCO2 42.26 AE 0.83, PO2 74.17 AE 2.51. The differences in PO2 were signi®cant (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.

“…7,8 Canine models have demonstrated speci®c anatomical changes during penile erection. 9 Arteriolar constriction and sinusoidal contraction occur with¯accidity.…”

Section: Discussionmentioning

confidence: 99%

Vasculogenic impotence and cavernosal oxygen tension

Strohl

et al. 2000

“…3,4,9,10,11,13 Sattar et al 11 reported that after injection of PGE 1 , the mean cavernous pO 2 in the control group was signi®cantly different from that in the venogenic and the arteriogenic groups. Furthermore, our data reveal that the femoral artery pO 2 results as well as cavernous pO 2 and sO 2 results following intracavernosal papaverine injection were different in patients with organic erectile dysfunction compared to patients with psychogenic erectile dysfunction.…”

Section: Discussionmentioning

confidence: 99%

Cavernous oxygen tension in the patients with erectile dysfunction

Tarhan¹,

Kuyumcuoğlu²,

Kolsuz³

et al. 1997

We designed a study consisting of 27 consecutive patients with erectile dysfunction in order to evaluate the role of cavernous oxygen tension. Patients were completely evaluated by history, physical examination, multiple blood analyses, serum testosterone level measurements, papaverine test, color duplex sonography and dynamic infusion cavernosometry-cavernosography. Blood gas samples were obtained from femoral artery and corpus cavernosum before drug injection and also from corpus cavernosum at 5, 10, 20, 30, 40min following drug injection. Aetiologic classi®cation of erectile dysfunction in our patients was as follows: psychogenic in 8, cavernosal failure in 14 and arterial disease in 5 cases. At¯accidity, no signi®cant differences were found in the mean pO 2 , sO 2 , pCO 2 and pH values of patient groups. After injection of intracavernous papaverine, results of the cavernous pO 2 (P`0.05), sO 2 (P`0.05) levels were found to be statistically signi®cantly different between patients with vascular and psychogenic erectile dysfunction. Analysis of maximal cavernosal oxygen tension and PSV revealed statistically signi®cant correlation (r 0.66, P`0.001). The results of this study suggest that changes in arterial and cavernosal pO 2 and sO 2 values may be contributing factors or co-factors in erectile failure.

“…This is in accord with investigators who hold the view that electrostimulation of the cavernous nerve, which is autonomic, induces changes in blood¯ow, culminating in full erection with an intracorporeal pressure below the systolic blood pressure. 33 Stimulation of the pudendal nerve, which is somatic, causes contraction of the ischiocavernosus muscle which raises the intracorporeal pressure to above the systolic blood pressure. 33 The question may arise of why did the patients respond with full erections to CN stimulation, but not to intracavernous pharmacotherapy.…”

Section: Discussionmentioning

confidence: 99%

Magnetic stimulation of the cavernous nerve for the treatment of erectile dysfunction in humans

El-Sibai

Shafik

2000

A recent study in dogs has demonstrated that magnetic stimulation (MS) of the cavernous nerve produced an increase of the intracorporeal pressure and full penile erection. In view of these results, we tested the possible application of this procedure in humans with erectile dysfunction (ED). The study comprised 32 patients with ED (age 38.3 AE 9.6 y) and 20 healthy volunteers (age 36.8 AE 8.8 y). Routine erectile function tests suggested that impotence was neurogenic. A magnetic coil was placed over the dorsal aspect of the penis in the vicinity of the symphysis pubis. MS was performed using a stimulation of 40% intensity, 20 Hz frequency, 50 s on and 50 s off for 10 minutes duration. In the healthy volunteers, the coil was placed as aforementioned but was not activated. The intracorporeal pressure was recorded and penile tumescence and rigidity observed during MS in the patients and without stimulation in the controls. MS led to gradual increase in length and diameter of the penis until full erection was achieved; the penis became ®rm, rigid and pulsatile. The intracorporeal pressure increased signi®cantly (P`0.0001) at full erection. Mean latency to full erection was 19.3 AE 3.4 s. Upon off-stimulation, penile erection and intracorporeal pressure returned to baseline after a mean of 22.7 AE 3.2 s. Penile and pressure response to MS was resumed after an off-time of 50 s. The response was reproducible in®nitely if the off-time was observed. The controls showed no penile tumescence or rigidity or increase of the intracorporeal pressure. In conclusion, MS of the cavernous nerve is effective in inducing penile rigidity. It is a simple, easy and non-invasive method which has no adverse effects. It might prove to be suitable for application in patients with ED.