Penile prostheses continue to be one of the mainstays of treatment
for erectile dysfunction (ED), though their role has become that of a last resort therapy
used after all other nonsurgical therapies have failed.
A penile prosthesis is particularly beneficial for men with ED and
Peyronie's disease, as their ED and deformity can be corrected at the same time.
Penile prostheses are of two major types: semirigid and inflatable.
The design and functional limitations of each type need to be understood by the implanting
urologist. Proper selection of the device and of operative candidates will maximize the
chance of a satisfactory outcome.
Implantation of penile prostheses can be performed under local,
regional or general anesthesia. Most implanting urologists prefer either the penoscrotal
approach or infrapubic incision, depending on the type of prosthesis to be implanted.
Complications of prosthesis implantation include various
intraoperative complica- tions which occur during dilatation of the corpora cavernosa
(e.g. septal crossover, tunical disruption and urethral perforation), infection, scrotal
hematoma, and mechanical failure of the device.
Postoperatively, patients must avoid sexual intercourse for 5 to 6
weeks. The most common patient complaints with prostheses are of `coldness' of the penile
shaft and decreased sensitivity. Delayed or anejaculation is also a rare complaint.
Vascular surgery for ED is still at an immature state of evolution.
It is most appropriate for patients who exhibit a single mechanism of vasculogenic ED,
namely failure of cavernosal perfusion and a segmental correctable lesion amenable to bypass, endarterectomy or stenting.
The ideal candidate for penile revascularization is a
young patient with a history of trauma and a minimum of modifiable vascular factors.
Patient selection criteria include: (a) age <60
years; (b) history of normal sexual function; (c) absence of endocrine and neurological
abnormalities; (d) absence of diabetes; (e) absence of risk factors for vascular disease;
(f) delayed or absent responses to intracavernosal injections of vasoactive drugs; (g)
penile duplex sonography documenting cavernosal blood flow <25 cm/s during the first 5
minutes; (h) pudendal angiogram documenting dysfunctional or absent cavernosal arteries;
and (i) minimal or no veno-occlusive dysfunction.
Surgical techniques include direct and indirect penile
revascularization procedures and the newer ‘triple-anastomosis’ technique.
Postoperative complications of surgery for
vasculogenic ED include mechanical disruption of microvascular anastomoses, anastomotic
occlusion, glans hyperemia, diminished penile sensation or penile pain, penile length loss
due to fibrosis of the suspensory and fundiform ligaments, wound infection, priapism and
persistent edema.
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