Evaluation of the Effects of Different Prostate Surgeries on Urinary and Sexual Function

Benign prostatic hyperplasia (BPH), one of the most common diseases of aging men, can be associated with bothersome lower urinary tract symptoms (LUTS) that affect quality of life. The prevalence of histopathologic BPH is age dependent, with initial development usually after 40 years of age. Similar to that of histologic evidence, the prevalence of bothersome symptoms also increases with age. Approximately half of all men who have a histologic diagnosis have moderate to severe LUTS.

The other common disorder associated with BPH is sexual dysfunction based purely on age. Sexual dysfunction encompasses not only erectile dysfunction (ED), but also ejaculation abnormalities, difficulty in reaching orgasm, decreased libido and overall dissatisfaction. Many studies suggest that the presence of LUTS is a risk factor for sexual dysfunction. Increasing life expectancy has been associated with improvements in the health and quality of life of the elderly, and many studies examined the sexuality of these groups of subjects and reported that their interest in sex persist.

By reviewing the literature, the effect of different modalities for treating BPH, including medical, open surgical, endourological procedures, on urinary function has been extensively discussed and to a less extent on sexual function. A significant problem which arises when discussing the sexual function with patients and partners, and when reviewing the literature, is to know which aspect of male sexual function is being referred to.

Transurethral resection of the prostate (TURP) is still considered the gold standard in treating BPH. However, most authors accept that there will be some impairment of sexual function secondary to this procedure. The exact magnitude of this problem has been difficult to assess by reviewing the published literature. Most of the large series reported ED rates of 10 to 15%. (11\&12) The etiology of ED secondary to TURP is poorly understood. Most likely it is secondary to electrical trauma to the cavernous nerves close to the prostate apex at 5 and 7 o'clock positions. Furthermore, thrombosis of the cavernosal arteries may result from mechanical trauma or from thermal damage.

Post TURP ejaculatory dysfunction was reported and documented to be in the form of retrograde ejaculation in between 25-99 %. The mechanism for that was destruction of the bladder neck mechanism which is responsible for sympathetic mediated occlusion of the bladder neck during ejaculation ending in forward expulsion of the ejaculate.

Since introduction of TURP as an effective tool for treatment of BPH, many endo-urologic techniques were tried to overcome the limitations and drawbacks of this gold standard procedure mainly caused by perioperative bleeding requiring transfusion or re-intervention, irrigation fluid absorption (TUR syndrome) and need for hospital stay.

Currently holmium laser enucleation of the prostate (HoLEP) seems to be an attractive alternative to standard TURP. The efficacy and safety of HoLEP have been demonstrated even in cases of large prostates that otherwise would usually require open prostatectomy. In several comparative randomized studies, HoLEP was found to be superior to TURP in term of catheter time, hospital stay, weight of removed tissue, blood loss but with longer operative time.

However, its impact on male sexual function has not been well established. The successful outcome of relief of LUTs is postulated to favor improving the overall sexual function. However, other factors including laser heating effect, is hypothesized to contribute to postoperative erectile dysfunction.

The safety of bipolar TURP is enhanced by the use of normal saline eliminating the incidence of the metabolite toxicities and dilutional hyponatremia and the physics of electrical current return theoretically reduce the thermal tissue damage at the site of surgery or at a distant site by faulty patient grounding ( patient return electrode pad ). Urologists have observed better intra-operative visibility during bipolar resection, which may also enhance resident education. The deep coagulation effect of bipolar resection is thought to contribute in the postoperative sexual dysfunction. However, sexual function after bipolar TURP is still not well established in the literature.

To the best of the investigators' knowledge there is no any prospective study in the literature comparing these three widely available procedures monopolar TURP, bipolar TURP and HoLEP in term of their urinary, erectile and ejaculatory outcome.