Penile prosthesis

Penile prostheses are semi-rigid malleable or inflatable rods, which are inserted surgically into the corpus cavernosa to allow erections (Fig. 48-2). The malleable rods are rigid at all times, but may be bent into position by the patient when desired. The inflatable prostheses remain flaccid until the pump within the scrotum moves fluid from a reservoir to the cylinders within the penis. Detumescence is achieved when the fluid is then transferred back to the reservoir by activating a release button. 

Penile prostheses provide penile rigidity snitable for vaginal intercourse and are associated with a greater than 90% patient satisfaction rate. The surgical success rate after insertion is 82% to 98%. ... 

Injury to the metallic core of malleable prosthe-ses can be detected on pelvic radiographs (Cohan et al. 1989 Hovsepian and Amis 1989 Chiou et al. 1999). Despite the excellent radiopacity of the silver core, however, diagnosis is often difficult, and many fractures have been missed or their severity underestimated using standard radiographic technique. Modern inflatable penile prostheses usually contain saline, which cannot be seen radiographically. 

Surgical insertion of a penile prosthesis, the most invasive treatment for ED, is used after failure of less invasive treatments and for patients who are not candidates for other treatments. 

Siloxane-containing devices have also been used as contact lenses, tracheostomy vents, tracheal stents, antireflux cuffs, extracorporeal dialysis, ureteral stents, tibial cups, synovial fluids, toe joints, testes penile prosthesis, gluteal pads, hip implants, pacemakers, intra-aortic balloon pumps, heart valves, eustachian tubes, wrist joints, ear frames, finger joints, and in the construction of brain membranes. Almost all the siloxane polymers are based on various polydimethylsiloxanes. 

Vacuum coniriclion device Penile prosthesis (2 piece)... 

When treatments for erectile dysfunction are needed, the least invasive forms of treatment should be used first, as they produce the lowest incidence of serions adverse effects. VEDs or phosphodiesterase inhibitors are therefore considered first-line treatments. If these fail, intracavemosal alprostadil injection therapy can be initiated. If this fails, the patient can be tried on a combination of intracavemosal alprostadil pins VED, combination intracavemosal therapy, or intra-nrethral alprostadil. If this fails, the patient may require insertion of a penile prosthesis. 

Hsu GL, Brock G, Martinez-Pineiro L et al (1994) Anatomy and strength of the tunica albuginea its relevance to penile prosthesis extrusion. J Urol 151 1205-1208 Kim ED, Blackburn D, McVary KT (1994) Post-radical prostatectomy penile blood flow assessment with color flow Doppler ultrasound. J Urol 152 2276-2279 Wessells H, Lue TF, McAninch JW (1996) Penile length in the flaccid and erect states guidelines for penile augmentation. J Urol 156 995-997... 

Penile prosthesis implantation is an effective surgical option for treatment of severe vascular erectile dysfunction. However, it remains the third-choice therapeutic option after failure of other less invasive procedures (Wespes et al. 2003 Wespes et al. 2006). 

Implantation of an inflatable penile prosthesis is usually the surgical treatment of choice after unsuccessful medical therapy Implantation of other types of prosthesis or other surgical procedures can be considered only in selected cases (Carson et al. 2000). 

Rods of silicone rubber of semi-rigid and malleable penile prosthesis present at ultrasound as echo-poor structures within the corpora cavernosa (Basu et al. 2002). The central metal core of malleable prostheses appears as an echogenic structure with a characteristic comet-tail artifact. 

Fig. 16.5a-d. Inflatable penile prosthesis. a,b Axial ultrasound images of the penile shaft obtained before (a) and after (b) inflation of the corporeal cylinders show the cylinders as anechoic structures replacing the cavernosal tissue, c Abdominal reservoir ( ). d Scrotal pump ) and deflation valve (open arrow)... 

MRI has gained acceptance in the last years in evaluation of penile prosthesis (Pretorius et al. 2001 VossouGH et al. 2002). However, the characteristics of the prosthesis must be evaluated before the examination because some types of old devices... 

Small, M. R, H. M. Carrion, and 1. A. Gordon. 1975. Small-Carrion penile prosthesis. New implant for management of impotence. Urology 5 479-486. 

Hinds, P.R., Wilson, S.K., Sadeghi-Nejad, H., 2012. Dilemmas of inflatable penile prosthesis revision surgery what practices achieve the best outcomes and the lowest infection rates (CME). J. Sex. Med. 9, 2483-2491. http //dx.doi.Org/10.llll/j.1743-6109.2012.02932.x. quiz 2492. 

Besides evaluation of penile blood supply to the penis, MDCT can be indicated to evaluate large postoperative fluid collections and complications of urethral surgery such as diverticula, fistulas and postoperative strictures (Chou et al. 2005). Also prosthesis malfunction can be investigated in patients who are not candidates for magnetic resonance imaging. Moreover, in patients with penile and urethral malignancies, CT is often used after the operation to evaluate the pelvis in suspicious postoperative complications extending into the perineum and into the pelvis, such as fistulas and inflammation. Also tumor recurrence and pelvic lymphadenopathies can be evaluated effectively. 

Penile abscesses are uncommon. They usually result as a complication of an advanced or untreated superficial balanitis or cellulitis, from infection of the corpora cavernosa, or following a systemic infection with lymphatic or haematogenous dissemination (Sater and Vandendris 1989). Immuno-compromised patients are at high risk of developing a penile abscess. Diabetic patients may develop penile infections after surgical manoeuvres or prosthesis implantation. 

---