Penile Prosthesis: Difference between revisions

== Contraindications (8): ==

# '''<span style="color:#ff0000">Situational ED'''

# '''<span style="color:#ff0000">ED resulting from relationship conflict'''

# '''<span style="color:#ff0000">Potentially reversible ED'''

# '''<span style="color:#ff0000">Uncontrolled diabetes mellitus'''

# '''<span style="color:#ff0000">Noncompliance with concurrent medication (e.g., for hypertension or diabetes)'''

# '''<span style="color:#ff0000">Inability to follow instructions'''

# '''<span style="color:#ff0000">Hygiene issues and skin cleanliness'''

* '''<span style="color:#ff0000">Semirigid rods'''

**'''<span style="color:#ff0000">Malleable'''

**'''<span style="color:#ff0000">Positional'''

**'''<span style="color:#ff0000">2-piece'''

**'''<span style="color:#ff0000">3-piece'''

=== Semirigid rods ===

* Paired, solid cylinders that fill each corpus cavernosum

* '''Reducing surgical time decreases the risk of infection'''

* Incision and dissection down to corpora

** The three-piece device can be inserted through a scrotal or infrapubic incision.

** '''Narrower inflatable and semirigid devices should be available for all cases in the event that implanting a three-piece device becomes difficult'''.

* Cylinder placement

** The tunica albuginea of each corpus cavernosum is identified on either side of the urethra

** An incision is made in the tunica albuginea taking care to avoid the underlying cavernosal muscle

** Blunt scissors are used to develop a space between the tunica albuginea and cavernosal muscle

** Sequential dilation of the corpora is done using Hegar dilators.

*** The use of force is unnecessary and should be avoided to prevent perforation of the tunica albuginea and damage to the urethra at the meatus or the crus, which can occur during either distal or proximal dilation.

** The corporeal lengths should be measured distally and proximally to select an optimally sized cylinder

** The device is opened on the surgical field and prepared for implantation

** The cylinders are implanted

** A watertight closure of the corporotomy can be achieved with a running 3-0 PDS using a hemostatic stitch or by approximating the previously placed tagging 3-0 PDS

** '''Poor support of the glans penis by cylinder or rod tips leads to a drooping appearance of the glans, in which it appears to "flop" over the prosthesis'''.

*** This deformity may result from inadequate distal dilation, too short cylinders, or in the case of minor deformity, variations in anatomy where the corpora cavernosum does not extend completely under the glans.

*** '''For a severe deformity, definitive correction involves removing both cylinders, perforating the distal corpora with scissors, resizing, and then inserting longer cylinders or the same cylinders with longer rear tip extenders.'''

*** '''For mild defects, dorsal plication of the glans back onto the shaft of the penis (glansplasty) is preferable when there are minor but otherwise bothersome degrees of poor glanular support.'''

* Pump placement

* '''<span style="color:#ff0000">Reservoir placement</span>'''

** '''Before reservoir placement, it is important to ensure the bladder is empty to avoid bladder perforation.'''

** '''<span style="color:#ff0000">The reservoir is typically placed in the space of Retzius.</span>'''

*** '''<span style="color:#ff0000">Submuscular reservoir placement with a flat reservoir or a separate incision should always be performed in all patients after previous surgery involving the space of Retzius (robotic prostatectomy, radical cystectomy, and abdominoperineal resection and in patients with history of pelvic fracture with bladder rupture and pelvic surgery)</span>'''

* '''Closure'''

** '''A closed-suction drain should be used if the surgeon is not satisfied with hemostasis'''

== Complications ==

** '''<span style="color:#ff0000">Corpora cavernosa perforation'''

*** To prevent distal or proximal crossover into the contralateral corpus during initial dilation, constant traction should be applied to the shaft of the penis by pulling on the glans, and the curvature of the scissors should be maintained away from the midline of the penis, with the tips next to the tunica albuginea.  

***'''If crossover occurs, it is usually preferable to recognize it and correct it when recognized, rather than after further dilation or insertion of the cylinders.'''

*** '''Most likely location for perforation is at the septum'''

*** '''Distal perforation'''

**** '''Evaluated by exposing the damaged corpus apex through a transverse incision of the skin and tunica albuginea near the glans'''

**** '''Management'''

***** '''A small hole can usually be''' located distally on the medial aspect of the cavernosal cavity and '''repaired''' using separate PDS stitches. The distal apex of the corpora needs to be closed with a second running suture, and '''a slightly shorter prosthetic cylinder is selected for the perforated side;''' this is necessary to prevent the distal tip of the cylinder from resting on the urethral suture repair.

***** '''A more conservative approach would be to terminate the procedure and bring the patient back for implantation 3 months later.'''

****** The disadvantage of this strategy is that the length of the shaft is foreshortened, and dilation of the scarred corpora is much more difficult.

***** '''If the perforation occurs after both corpora are dilated, a semimalleable cylinder can be placed in the nonperforated side to preserve penile length.'''

*** '''Proximal perforation'''

**** '''Evaluated by placing a dilator in each crura, and their heights can be compared to confirm that one has penetrated too deeply inside the perineum.'''

**** '''Management'''

***** '''Repair''' by anchoring the cylinders to the surrounding corpora tissue by placing stitches above and below the input tubing, which prevents the cylinder from proximal migration and allows the perforation to heal.

** '''<span style="color:#ff0000">Urethral perforation'''

*** '''<span style="color:#ff0000">Management'''

**** '''<span style="color:#ff0000">Abandon the procedure and divert the urine with a urethral catheter''' until deferred repair.

***** '''Urethral repair would be difficult and is unnecessary.'''

***** '''If the contralateral malleable cylinder has already been placed and there is no septal perforation, then it may be left in place.'''

***** '''If this occurs with an inflatable prosthesis, the entire device should be removed and the urethra allowed to heal.'''

* '''Infections'''

** '''<span style="color:#ff0000">Overall infection rates following initial penile prosthesis insertion range from 1-3%</span>; rate is significantly higher (7-18%) for revision surgery'''

** '''Most infections are caused by bacteria on the skin that attach to the device and are then introduced into the patient'''

*** '''The bacterial contamination that causes infection most often occurs at the time of surgery and typically involves organisms that colonize the skin, such as Staphylococcus epidermidis, Staphylococcus aureus, and Candida albicans'''

*** Specially coated three-piece devices have been developed to inhibit bacterial adhesion and proliferation. These coatings have decreased the incidence of infection by 50-70%,

** '''The most important factors to minimize the risk of device infection include the use of antibiotic-coated prostheses and procedures that decrease inoculating bacteria into the surgical wound (i.e., alcohol skin preparation, a no touch surgical technique, and perioperative antibiotic use).'''

*** '''Other risk factors for device infection related to patient history include poor patient hygiene, spinal cord injury, urinary tract infection, distant sites of infection, and revision surgery performed for previous device infection'''

*** '''It is unclear if diabetes or immunosuppression are associated with risk of infection'''

*** Intraoperative risk factors for infection include inadequate skin preparation with alcohol/chlorhexidine; prolonged surgical time (i.e., >2 hours); prolonged and repeated exposure of components of the prosthesis to patient’s skin; frequent repositioning and resizing of the cylinder, pump, or reservoir; scrotal hematoma (particularly if liquefied); and not changing gloves before handling the device; a postoperative factor associated with infection risk is prolonged hospitalization.

** '''Diagnosis and Evaluation'''

*** '''History and Physical Exam'''

**** '''History'''

***** '''<span style="color:#ff0000">Clinical deterioration with persistence of pain and tethering at 3-4 weeks after surgery suggests an infection</span>'''

****** '''Pain that does not seem to improve and is persistent or increased at 2-weeks after surgery should not prompt the use of antibiotics'''

******* '''If the device is not infected, the patient should experience clinical improvement within the next 7-14 days.'''

******* If the device is infected, antibiotics are useless at this point and may delay diagnosis'''.'''

***** '''Fever, erythema, swelling, elevated white blood cell count, and incision drainage are late signs and symptoms of infection and are usually not observed at the initial postoperative visit.'''

***** '''The sooner an infection is diagnosed, the better the chance for successful salvage''' and aggressive early salvage should be considered before systemic symptom such as fever, elevated white blood count, erythema, and abscess formation of scrotum occur

*** Imaging

** '''Management'''

*** '''<span style="color:#ff0000">Infection necessitates the removal of all device components as well as any permanent sutures or graft material used during corporeal reconstruction</span>'''

**** The use of systemic antibiotics to treat symptomatic patients is typically insufficient because of the biofilm and attempts to remove only part of an infected device typically results in persistent infection

*** '''A “salvage” procedure involving removal of the infected prosthesis, wound washout, and immediate device replacement can help facilitate reimplantation and preserve penile length.'''

**** '''Contraindications to salvage prosthesis:'''

***** '''Patients presenting with enterococcus, tissue necrosis, sepsis, diabetic ketoacidosis, or cylinder erosion into the urethra'''

* '''Device malfunction'''

** '''The most common types of malfunction in a three-piece prosthetic device include cracks in the silicone tubing, leaks, and pump disruption'''

** '''Management'''

*** '''If malfunction occurs'''

**** '''Within a few months after implantation: consider replacing only the defective component, especially if this avoids a repeat corporeal incision'''

**** '''After the device has been in place for >2 years: complete replacement is indicated'''

** '''Postoperative complications occurring less frequently than infection and device malfunction include erosion, S-shaped penile deformity, poor glans support (see above), and scrotal hematoma'''.

*** '''Erosion'''

**** '''Typically occurs months or years after implantation'''

**** '''Can manifest in several different locations.'''

**** '''Management'''

***** '''Complete removal of all the components of the device, regardless of the location and possible salvage replacement.'''

****** '''If only one of the cylinder tips has eroded through the meatus, the entire device needs to be removed, including the pump and reservoir, and a malleable cylinder is placed in the noneroded side only, to prevent shortening of the penis.'''

****** '''The perforation must be allowed to heal for 8 to 12 weeks before reimplantation is attempted'''

** '''Pain only when the device is inflated during intercourse'''

*** '''May indicate that the cylinders are too large and are buckling, causing pain.'''

*** '''MRI scan with the prosthesis inflated is the best imaging modality to prove the possible size discrepancy and buckling is the next step.'''

*** '''If the diagnosis is confirmed, revision of the penile prosthesis with placement of smaller cylinders will usually resolve the problem'''