Penile vascular surgery for treating erectile dysfunction (ED) is still regarded cautiously. Thus we reviewed relevant publications from the last decade, summarising evidence-based reports consistent with the pessimistic consensus and, by contrast, the optimistically viable options for vascular reconstruction for ED published after 2003. Recent studies support a revised model of the tunica albuginea of the corpora cavernosa as a bi-layered structure with a 360° complete inner circular layer and a 300° incomplete outer longitudinal coat. Additional studies show a more sophisticated venous drainage system than previously understood, and most significantly, that the emissary veins can be easily occluded by the shearing action elicited by the inner and outer layers of the tunica albuginea. Pascal’s law has been shown to be a significant, if not the major, factor in erectile mechanics, with recent haemodynamic studies on fresh and defrosted human cadavers showing rigid erections despite the lack of endothelial activity. Reports on revascularisation surgery support its utility in treating arterial trauma in young males, and with localised arterial occlusive disease in the older man. Penile venous stripping surgery has been shown to be beneficial in correcting veno-occlusive dysfunction, with outstanding results. The traditional complications of irreversible penile numbness and deformity have been virtually eliminated, with the venous ligation technique superseding venous cautery. Penile vascular reconstructive surgery is viable if, and only if, the surgical handling is appropriate using a sound method. It should be a promising option in the near future.

The human erectile mechanism is an intricate interplay of hormonal, vascular, neurological, sinusoidal, pharmacological, and psychological factors. However, the relative influence of each respective component remains somewhat unclear, and merits further study. We investigated the role of venous outflow in an attempt to isolate the key determinant of erectile function. Dynamic infusion cavernosometry and cavernosography was conducted on 15 defrosted human cadavers, both before and after the systematic removal and ligation of erection-related penile veins. Preoperatively, an infusion rate of more than 28.1 mL/min (from more than 14.0 to 85.0 mL/min) was required to induce a rigid erection (defined as intracavernosal pressure [ICP] exceeding 90 mmHg). Following surgery, we were able to obtain the same result at a rate of 7.3 mL/ min (from 3.1 to 13.5 mL/min) across the entire sample. Thus, we witnessed statistically significant postoperative differences (all P # .01), consistently elevated ICP, lower perfusion volumes, and a general reduction in time taken to attain rigidity. The cavernosograms provided further evidence substantiating the critical role played by erection-related veins, whereas histological samples confirmed the postoperative integrity of the corpora cavernosa. Given that our use of cadavers eliminated the influence of hormonal, arterial, neurological, sinusoidal, pharmacological, and psychological factors, we believe that our study demonstrates that the human erection is fundamentally a mechanical event contingent on venous competence.

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SummaryRecent studies substantiate a model of the tunica albuginea of the corpora cavernosa as a bi-layered structure with a 360° complete inner circular layer and a 300° incomplete outer longitudinal coat spanning from the bulbospongiosus and ischiocavernosus proximally and extending continuously into the distal ligament within the glans penis. The anatomical location and histology of the distal ligament invites convincing parallels with the quadrupedal os penis and therefore constitutes potential evidence of the evolutionary process. In the corpora cavernosa, a chamber design is responsible for facilitating rigid erections. For investigating its venous factors exclusively, hemodynamic studies have been performed on both fresh and defrosted human male cadavers. In each case, a rigid erection was unequivocally attainable following venous removal. This clearly has significant ramifications in relation to penile venous surgery and its role in treating impotent patients. One deep dorsal vein, 2 cavernosal veins and 2 pairs of para-arterial veins (as opposed to 1 single vein) are situated between Buck’s fascia and the tunica albuginea. These newfound insights into penile tunical, venous anatomy and erection physiology were inspired by and, in turn, enhance clinical applications routinely encountered by physicians and surgeons, such as penile morphological reconstruction, penile implantation and penile venous surgery.

ObjectiveTo study the drainage proportions from the corpora cavernosa in defrosted human cadavers, as the veins related to penile erection were recently depicted to comprise the deep dorsal vein (DDV), a pair of cavernous veins (CVs) and two pairs of para-arterial veins (PAVs), as opposed to a single DDV between Buck’s fascia and the tunica albuginea of the human penis.Materials and methodsWith no formalin fixation, 10 defrosted male human cadavers were used for this study. After injecting a 10% solution of colloid, and with the intracavernous pressure (ICP) fixed at 90 mmHg, the perfusion rate was recorded before and after the DDV, CVs and PAVs were removed, respectively. Finally, measurements were again recorded after penile arterial ligation. Cavernosography was used if required.ResultsThe mean (range) perfusion rate for maintaining the ICP at 90 mmHg was 30.2 (15.5–90.8) mL/min, whereas the arterial perfusion rate was 2.8 (0.3–3.9) mL/min. The mean (range) drainage proportion of the corpora cavernosa was 60.5 (50.3–69.7)%, 11.9 (5.8–22.9)% and 11.4 (5.2–15.0)% via the DDV, CVs and PAVs, respectively. The remaining drainage proportion was 15.6 (14.1–18.1)%. This study shows the separate drainage contributions of the DDV, CVs and PAVs to the corpora cavernosa of the human penis.ConclusionWe conclude that the venous drainage system of the corpora cavernosa is much more complex than the previous depictions of it, and the consequent focus on a single DDV. This also shows the independent role of each venous system.