Correspondence: Wayne J. G. Hellstrom, Department of Urology, Tulane University Health Sciences Center, 1430 Tulane Ave. SL-42, New Orleans, LA 70112, USA. E-mail: [email protected]
Keywords: erectile dysfunction, pelvic fracture urethral injury, penile revascularization, urethral stricture disease
Erectile dysfunction in urethral stricture and pelvic fracture urethral injury patients: diagnosis, treatment, and outcomes P. Sangkum J. Levy F. A. Yafi and W. J. G. Hellstrom
Received: 24-Sep-2014 Revised: 30-Dec-2014 Accepted: 6-Jan-2015
Department of Urology, Tulane University School of Medicine, New Orleans, LA, USA
SUMMARY Urethral stricture disease, pelvic fracture urethral injury (PFUI), and their various treatment options are associated with erectile dysfunction (ED). The etiology of urethral stricture disease is multifactorial and includes trauma, inflammatory, and iatrogenic causes. Posterior urethral injuries are commonly associated with pelvic fractures. There is a spectrum in the severity of both conditions and this directly impacts the treatment options offered by the surgeon. Many published studies focus on the treatment outcomes and the relatively high recurrence rates after surgical repair. This communication reviews the current knowledge of the association between ED and urethral stricture disease, as well as PFUI. The incidence, pathophysiology, and clinical ramifications of both conditions on sexual function are discussed. The treatment options for ED in those patients are reviewed and summarized.
INTRODUCTION Urethral stricture is a scarring process of the urethral mucosa and surrounding spongy tissues of the corpus spongiosum (Latini et al., 2014). The male urethra is divided into four parts: prostatic, membranous, bulbar, and penile urethra. Each urethral segment has recognized differences in the surrounding anatomy and apparent etiologies of urethral narrowing. The term ‘urethral stricture’ refers to anterior urethral disease because the prostatic urethra and the bladder neck are not covered by the corpus spongiosum. Historically, urethral stricture disease was most often associated with gonococcal urethritis. With the evolution of endoscopic techniques for the treatment of various genito-urinary conditions (e.g., transurethral resection for benign prostatic hyperplasia, ureteral assess for stone disease), the etiologies of urethral strictures have changed dramatically (Lumen et al., 2009). Instrumentation is a possible cause of injury to the urethral mucosa. The partial loss of urethral mucosa represents the initiation of the scarring process of the corpus spongiosum or spongiofibrosis (Latini et al., 2014). Other causes of strictures include prior hypospadias repair, urethral catheterization (prolonged or traumatic) related to non-urologic conditions, blunt or penetrating external trauma, and idiopathic causes (Lumen et al., 2009). Posterior urethral injury is usually associated with pelvic fractures. Shear mechanisms resulting in © 2015 American Society of Andrology and European Academy of Andrology
pelvic fracture may tear through the bulbomembranous urethra and lead to urethral disruption and displacement. Treatment options vary as a consequence of these differences. More traditional therapies for urethral stricture disease include urethral dilation, direct visual internal urethrotomy (DVIU) and a variety of open urethroplasty techniques. Treatment options are selected based on the severity (length and density), location, patient comorbidities, and surgeon preference. The urethral stricture and pelvic fracture urethral injury (PFUI) literature recognizes an association between erectile dysfunction (ED) and ejaculatory dysfunction (Feng et al., 2008; Erickson et al., 2010a). It is postulated that surgical treatment of urethral stricture itself might affect sexual function. The objective of this article is to review the associations between urethral stricture, PFUI and ED; namely incidence, pathophysiology, and the consequences on sexual function that occur after each type of operative intervention. The subsequent treatment of ED in this cohort is also addressed.
ED IN URETHRAL STRICTURE PATIENTS The true incidence of ED in urethral stricture patients is not known. Currently, there are only limited studies aimed primarily at evaluating the incidence of ED in this population. There are many factors that affect the incidence of ED in these patients, Andrology, 2015, 3, 443–449
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including baseline erectile function, the underlying cause of the stricture, the location, and severity of the stricture. The incidence of ED is mostly obtained from published studies that have compared the pre-operative and post-operative rates of ED in patients who have undergone anterior urethroplasty. Erickson et al. (2010a) have reported that 44% of these patients had some degree of ED before surgery. In addition, 25% of these patients reported pre-operative ejaculatory dysfunction (Erickson et al., 2010b). Other investigators have documented that urethral stricture had a significant impact on sexual life, particularly in relation to ejaculatory function. As a matter of fact, 35% of surveyed patients expressed fear of worsening quality of sexual life postoperatively (Palminteri et al., 2013). The etiology of urethral stricture varies widely from one patient to another. As such, it is difficult to ascertain whether the etiology of ED is the urethral stricture itself, or the psychological impact of the urethral stricture which may affect sexual interest and erectile function prior to definite treatment, or other causes unrelated to the urethral stricture. As such, large-scale prospective trials, using standardized questionnaires and penile duplex doppler ultrasounds (PDDU) are necessary to clearly demonstrate the incidence and pathophysiology of ED in urethral stricture patients.
ED IN PFUI PATIENTS There is more published data on the incidence of ED in PFUI patients than urethral stricture patients. Perineal trauma and pelvic fracture cause posterior urethral injury in 13% of patients (Lumen et al., 2009). Urethral injury is a major risk factor for ED after pelvic fracture. Forty-two percent of PFUI patients have ED compared with 5% of pelvic fracture patients without urethral injury (King, 1975). However, if one studies the population of patients with pelvic fractures or blunt perineal trauma, this accounts for only 3% of ED patients (Harwood et al., 2005). Clinicians postulate neurovascular injury as the likely cause of ED in traumatic urethral injury patients. Cavernous nerves and branches of the internal pudendal artery are located near the apex of the prostate and pass through the urogenital diaphragm to enter the corporal bodies. The distal internal pudendal artery becomes the common penile artery, which gives rise to the cavernosal (deep penile) and dorsal penile arteries, which are vital for penile tumescence (Rogers & Rocha-Singh, 2012). Pelvic fracture directly injures the urogenital diaphragm, cavernous nerves and arteries, especially when pubic symphysis diastasis occurs (Feng et al., 2008). The incidence of ED in PFUI patients secondary to pelvic fracture and/or perineal trauma ranges from 27.5 to 72% based on diagnostic abnormalities observed on nocturnal penile tumescence studies (Shenfeld et al., 2003; Feng et al., 2008). Penile duplex doppler ultrasound documented that 48.7% of these patients had arterial ED, 14.6% had venous leak and 36.5% had non-vascular ED, most likely secondary to neurogenic causes (Fu et al., 2012). A multivariate analysis documented that diastasis of the pubic symphysis, lateral prostatic displacement, and a long urethral gap at surgery (all of which occur with more severe pelvic traumas) are the predictors of ED after pelvic fracture urethral injuries with an odds ratios (OR) of 15.9, 6.9, and 2.0, respectively (Koraitim, 2013). The mean length of the urethral gap in patients with normal erectile function was 2.2 1.3 cm, whereas that in patients with ED was 3.3 1.4 cm (Koraitim, 2013). Age at the onset of urethral injury is another risk factor for ED. There is 444
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ANDROLOGY higher risk of ED after pelvic fracture urethral injury in children (