Revascularization of the corpora cavernosa in ischemia-induced erectile dysfunction

Revascularization of the cavernous bodies (CB) has its place in a highly selected patient population as the only causal therapy for erectile dysfunction (ED) and provides an alternative to the implantation of alloplastic erectile aids. The indication for arterialization of the CB is currently only established when conservative treatment has failed. The most important criteria for the intervention are controversial: an age of under 50, an incidence of not more than two classical risk factors for impotence and the exclusion of diabetes mellitus. The leading revascularization procedure in German-speaking countries comprises arteriovenous shunting of the inferior epigastric artery with the dorsal vein and artery of the penis. A retrospective analysis of results is problematic due to the nonuniform indicational criteria, the multiplicity of applied revascularization procedures and a nonstandardized follow-up. Subjective assessment of improved erectility is the sole target criterion in the majority of studies. Therapeutic results range from 33 to 87% with regard to subjective success rates. Attempts to objectify the treatment results were made in only few of the studies and disclosed bypass patency in 44 to 92% one year after the intervention. The conclusions drawn at the last "Consensus Development Conference on Impotence" (CDCI) of the National Institutes of Health (NIH) in Washington have not lost their topicality in view of the great number of still unanswered questions. There the recommendation was made in 1992 to perform penile arterialization only in controlled prospective clinical trials. The European Urological Association (EUA) is currently organizing a Consensus Conference that will provide the framework for prospective studies that can serve as a basis for clarifying the open questions.     

Ultrastructual changes of corpora cavernosa in vascular erectile dysfunction

Corpora cavernosa of 4 impotent patients with arterial pathology and 6 with venous insufficiency were studied by electron microscopy. The findings in all of the smooth muscle samples were the following: pronouned thickening of the basal lamina; marked reduction of contractile myofilaments and electron dense bodies; finger-like cytoplasmic projections; increase in mitochondria with swelling and aggregation; huge protrusions of nuclear membrane into the cytoplasm; increased proportion of interstitial matrix to smooth muscle cells. These were more marked in the dark than in the light cells, which was considered as the beginning of degeneration. Another finding was degenerative changes in the endothelial cell lining of the sinusoids, especially denudation, fragmentation and marked thickening of the basal lamina. Severity of the symptoms did not change in any of the patients with different pathologies. So, we can assume that the pathological alterations may be due to chronic penile vascular insufficiency or vice versa.     

The hypoactive corpora cavernosa with degenerative erectile dysfunction: a new syndrome

Background

In a group of 22 patients with erectile dysfunction, vasculogenic, neurogenic, endocrinologic or psychogenic investigations failed to find a cause for their erectile dysfunction. The electro-cavernosograms of these patients recorded a diminished activity. We investigated the hypothesis that diminished corpus cavernosum electromyography activity was the cause of erectile dysfunction in these patients.

Methods

The study comprised the above mentioned 22 patients (study group, 43.8 ± 5.9 SD years) and 15 healthy volunteers (control group, 41.8 ± 5.1 SD years). The electro-cavernosograms were recorded in the flaccid, erectile and detumescent phases by 2 electrodes inserted into the corpus cavernosum.

Results

The electro-cavernosogram of the healthy volunteers registered in the flaccid phase regular slow waves and random action potentials. The wave variables declined significantly in the erectile phase (p < 0.01). In the study group, the slow wave variables in the flaccid phase exhibited a significant decrease (p < 0.05) compared to the healthy volunteers, and the rhythm was irregular. Erection did not occur with sildenafil administration or intracavernosal papaverine injection, and penile implant was performed. Biopsy examination showed degenerated muscle fibers, and fragmented collagen and elastic fibers with areas of fibrosis.

Conclusion

A novel concept of the cause of erectile dysfunction was presented. Corpora cavernosa showed degenerative changes on histopathologic examination and exhibited diminished electromyography activity. They did not respond to sildenafil administration or intracavernosal papaverine injection. Penile implants were the only treatment. The condition is given the name 'hypoactive corpus cavernosum'. The cause of corpus cavernosum degenerative changes needs further study.     

Comparative analysis of the penis corpora cavernosa in controls and patients with erectile dysfunction

OBJECTIVE: To evaluate the presence of structural disorders of the corpora cavernosa in patients with erectile dysfunction (ED), as despite new drugs being effective in many men with ED, some aspects of structural disorders of the corpora cavernosa remain unknown. MATERIALS AND METHODS: Biopsy specimens were taken from the corpora cavernosa of seven patients (mean age 57.8 years, range 51-72) with severe ED who had a penile prosthesis implanted. The controls tissues were fragments of corpora cavernosa obtained from autopsies of six men (mean age 52.3 years, range 40-66) who died from causes unrelated to the urogenital system. For light microscopy, the specimens were processed routinely to paraffin wax, and by immunohistochemistry to evaluate elastic fibres, and by Masson's trichrome to analyse collagen and smooth muscle fibres. Stereological methods were used to quantitatively evaluate the different elements (as a percentage). RESULTS: The percentages of the different elements in the human penis of controls and men with ED, respectively, were: elastic fibres 13.2% and 9.1%; collagen fibres 40.8% and 41.6%; and smooth muscle, 40.4% and 42%. CONCLUSIONS: In patients with ED there was a statistically significant reduction in the percentage of elastic fibres, but no statistically significant difference in collagen and smooth muscle fibres, and no appreciable differences in collagen distribution between the groups.     

Ultrastructural changes of corpora cavernosa in men with erectile dysfunction and chronic renal failure

Erectile dysfunction (ED) is a common and often distressing side effect of renal failure. Uremic men of different ages report a high variety of sexual problems, including sexual hormonal pattern alterations, reduced or loss of libido, infertility, and impotence, thereby influencing their well-being. The pathogenic mechanisms include physiologic, psychologic, and organic causes. To determine the contribution of morphologic factors to impotence we studied the ultrastructure of the corpora cavernosa in 20 patients with end-stage renal disease who were treated with chronic dialysis and compared the findings with 6 individuals with no clinical history of impotence. Our results indicated that in male uremic patients with sexual disturbances there were major changes in smooth muscle cells. This was characterized by reduction of dense bodies in the cytoplasm, thick basement membranes, and increased interstitial collagen fibers with resultant reduction of cell-to-cell contact. In addition, there was thickening and lamination of basement membranes of endothelial cells and increased accumulation of collagen between nerve fibers. These alterations were more evident in patients with longer time on dialysis and were independent of type of primary renal disease. We hypothesize that ED in dialysis patients is not related to the primary disease but to the uremic state.     

Correction of disproportion of corpora cavernosa as cause of chordee in hypospadias

Correction of chordee is a basic step in hypospadias surgery. In some children with significant chordee, ventral deflection of the shaft will persist after all “chordee tissue” is excised from the surface of the corpora cavernosa. In the flaccid state, this persistent chordee may not be evident but is easily demonstrated with an artificial erection technique. The use of dorsal placation of the tunica albuginea to correct this deformity is emphasized.     

Corpora cavernosa ultrastructure in vascular erectile dysfunction

Open biopsy of the corpus cavernosum was performed in 13 nondiabetic patients with erectile dysfunction. The history and physical examination, sleep rigidity and tumescence monitoring, hormonal assays, duplex ultrasonography with papaverine, and cavernosometry and cavernosography, formed the basis of categorizing each patient into 1 of 5 etiological groups. These groups included neurogenic, moderate arterial, severe arterial, venous and fibrotic causes for organic erectile dysfunction. The cavernous smooth muscle and endothelium in each patient appeared to be normal on light and electron microscopy. We conclude that cavernous biopsy is of limited value to determine therapeutic options in patients with erectile dysfunction.     

Blood gas changes in the corpora cavernosa: metabolic and histomorphometric implications in the patient with erectile dysfunction

PURPOSE: We evaluated corpora cavernosa metabolism in flaccidity and in erection, analyzing some blood gas analytical parameters and comparing them by histomorphometric examination to find a direct relation between biochemical-metabolic parameters and histological data. MATERIALS AND METHODS: We selected 33 patients with erectile dysfunction and divided them into 2 groups, including 1-those with congenital penile deviation who were responders to prostaglandin E1, and 2-those with severe organic erectile dysfunction who were not responders to prostaglandin E1. We evaluated O(2) and CO(2) pressure, pH and O(2) saturation in blood samples. We then made a histomorphometric study of cavernous tissue. We obtained specimens by cavernous biopsies and calculated O(2) and CO(2) exchange, the Haldane effect and the respiratory quotient into the corpora cavernosa. All data were evaluated by statistical analysis. RESULTS: Mean O(2) arterial pressure and saturation +/- SD were lower in group 2 than in group 1 (74.85 +/- 8.78 versus 96.43 +/- 14.87 and 94.98 +/- 1.4 versus 97.35 +/- 0.83, respectively). Mean CO(2) arterial pressure was 35.59 +/- 4.78 group 1 versus 38.8 +/- 2.71 in group 2 with borderline statistical significance. The Haldane effect was superior in flaccidity than in erection because of the influence of arterial-venous O(2) difference and the respiratory quotient, which was also an inverse ratio. Cavernous histomorphometry showed that in group 1 smooth muscle was a mean of 38.8 +/- 8.94% of cavernous tissue versus 24.9% in group 2. CONCLUSIONS: Our study shows that starting with blood gas analytical data we can completely study the metabolism of the corpora cavernosa and its relationships to erectile dysfunction. Cavernous histomorphometry can suggest the presence of smooth muscle into cavernous tissue, whereas our mathematical elaboration allowed us to evaluate all data in a more complete manner.     

Venous surgery in erectile dysfunction.

According to the physiopathological process beyond it, veno-occlusive dysfunction (VOD) may be classified in organic or functional VOD. The former is caused by lack of control of smooth muscle relaxation, while the later is related with morphological alterations of the corporeal tissue. The differential diagnosis of those two types is fundamental when venous surgery is to be discussed. Functional VOD may be treated with sex therapy, while in organic VOD, surgical treatment may be considered. The experience with venous surgery for impotence at the H. Ellis Institute was not encouraging. Although a few patients were cured, the long-term follow-up showed that only 9 out of 57 patients were able to have a normal sexual life. New diagnostic tools, as well as a better understanding of the erectile mechanism, may lead to a better selection of cases with an improvement of the results in the future. Today, venous surgery remains as an option to patients with organic VOD, who are willing to accept a 45% probability of improvement for a few months, having been informed about all the other options in the treatment of erectile disorders.     

Traumatic rupture of the corpora cavernosa

Treatment of penile fracture, due to the low number of cases, still lacks adequate documentation. The authors present two cases of such pathology, which were treated conservatively, and presented penile deformities in the late follow up. Both conservative and surgical management are discussed; since surgery in these cases has low mortality and clinical treatment can be followed by various sequelae, the authors favour the former, stressing that it is mandatory in cases with urinary obstruction, progressive infiltration or cutaneous laceration.     

B超下阴茎海绵体"繁星征"与 ED

目的 探讨B超下阴茎海绵体出现的“繁星征”与ED的关系,研究其发病机制。方法 30例ED患者行阴茎海绵体B超检查,并与30例无ED志愿者行B超对照。另对l例ED“繁星征”患者行阴茎海绵体病理检查。结果 30例ED患者中,29例发现有B超下阴茎海绵体“繁星征”。其中26例全阴茎弥散分布强回声光点,为临床诊断的中、重度ED患者（IIEF-5评分〈11分）。另3例仅局限在一部分,且回声光点较少,为轻度ED（IIEF-5评分12～19分）。而无ED志愿者无此现象。1例“繁星征”患者病理检查为阴茎海绵体胶原纤维增生伴玻璃样变。结论 阴茎海绵体广泛纤维化是出现B超下“繁星征”的病理基础。因限制海绵窦充盈而影响阴茎勃起。外伤与炎症是其致病因素。     

Usefulness of electromyography of the cavernous corpora (CC EMG) in the diagnosis of arterial erectile dysfunction

Electromyography (EMG) of the corpora cavernosa (CC-EMG) is able to record the activity of the erectile tissue during erection, and thus has been used as a diagnostic technique in patients with erectile dysfunction (ED). The present study examines the usefulness of the technique in the diagnosis of arterial ED. A cross-sectional study was made of 35 males with a mean age of 48.5 years (s.d. 11.34), referred to our center with ED for >1 year. The patients were subjected to CC-EMG and a penile Doppler ultrasound study following the injection of 20 μg of prostaglandin E1 (PGE1). The patients were divided into three groups according to their response to the intracavernous injection of PGE1: Group 1 (adequate erection and reduction/suppression of EMG activity); Group 2 (insufficient erection and persistence of EMG activity); and Group 3 (insufficient erection and reduction/suppression of EMG activity). Patient classification according to response to the intracavernous injection of PGE1 was as follows: Group 1: six patients (17%), Group 2: 18 patients (51%), and Group 3: 11 patients (31%). Patients diagnosed with arterial insufficiency according to Doppler ultrasound (systolic arterial peak velocity <30 mm s(-1) in both arteries) were significantly older than those without such damage (54.5 versus 41.8 years, respectively; s.d. 11.12). The patients in Group 3 showed a significantly lower maximum systolic velocity in both arteries than the subjects belonging to Group 2. Likewise, a statistically significant relationship was observed between the diagnosis of arterial insufficiency and patient classification in Group 3. The confirmation of insufficient erection associated with reduction/suppression of EMG activity showed a sensitivity of 66.7% (confidence interval between 50 and 84%) and a specificity of 92.9% (confidence interval between 84 and 100%) in the diagnosis of arterial ED. Owing to the high specificity of CC-EMG response to the injection of PGE1, this test is considered useful as a screening technique in the diagnosis of arterial ED.     

Testosterone receptors in corpora cavernosa of penis

Despite existing information that most impotent patients have normal serum testosterone, testosterone is still used frequently in the treatment of impotence. In 11 patients who underwent penile implantation, we measured the presence of testosterone receptors in the corpora cavernosa. An average value of 1.82 fmol/mg of protein cytosol was found in this group of patients. This value is too low to obtain any significant improvement in erectile function following testosterone application. Testosterone hypogonadism will likely remain the only indication in which testosterone application might improve organically triggered impotence.     

Rupture of corpora cavernosa: clinical practice

Rupture of corpora cavernosa is a rare disease in young adults. In western countries, the most frequent cause is the so-called "faux pas du co?t". In the Middle East, masturbation and penis manipulations aimed at stopping morning erection are the most frequent causes. The fracture which is audible by the patient is accompanied by a rapid detumescence with progressive onset of a haematoma. Diagnosis is based on clinical findings but radiological investigations such as MRI, ultrasonography or cavernography may help localizing the exact fracture site. The treatment of albugineal ruptures is surgery, in an elective manner whenever possible; it consists in the eviction of the subcutaneous haematoma, the suture of the albuginea and treatment of a potentially associated urethral rupture. Conservative treatment is exceptional and limited to patients who reject surgery, since it generates more complications: painful erections, persistent haematoma with a risk of infection, arteriovenous fistula, impotence, and unrecognized urethral rupture. Patients must be clearly informed on all these complications.     

Abnormalities of the suspensory ligament of the penis as a cause for erectile dysfunction

Four patients are described with a defect in the suspensory ligament of the penis. In one patient this was traumatic in origin but in the other 3 aetiology appeared to be congenital. The clinical history, physical findings and treatment are summarised.     

Hemodynamics of canine corpora cavernosa during erection

Being able to induce erection by electrical stimulation of the cavernous nerves, we studied the hemodynamics of canine penile erection. Simultaneous recording of flow and pressure of the internal pudendal artery as well as pressure within the corpus cavernosum clearly demonstrated that increase of arterial flow preceded corporeal pressure increase. When saline was infused directly into the corpus cavernosum, with the aorta clamped, decreasing venous flow during erection could be demonstrated. Tumescence of the corpus cavernosum was found to be a result of active relaxation of sinusoidal spaces, active arteriolar dilatation, and active venous constriction. At full erection, there was still flow into and out of the corpus cavernosum, although it was reduced to only a fraction of a milliliter per minute.