Editing Penile Prosthesis (section)

== Types of Prostheses ==

=== Classification ===

* '''<span style="color:#ff0000">Non-inflatable'''
*#'''<span style="color:#ff0000">Malleable'''
*#'''<span style="color:#ff0000">Positional'''
*'''<span style="color:#ff0000">Inflatable'''
*#'''<span style="color:#ff0000">2-piece'''
*#'''<span style="color:#ff0000">3-piece''' (see [https://www.mdpi.com/2673-4397/3/1/1 Figure])
*At the present time in the US, 70% of patients are implanted with 3-piece inflatable devices, 20% are implanted with 2-piece devices, and 10% are implanted with semirigid rods.

=== Non-inflatable ===

* Also known as semirigid rods
*Paired, solid cylinders that fill each corpus cavernosum
* '''Subdivided into malleable vs. positional devices'''
** A malleable device has a central core that allows a patient to position the penis upward for sexual intercourse and downward at other times.
** A positional device incorporates a series of articulating polyethylene discs with a central metal cable support, which make it better able to maintain upward and downward positions

==== Advantages (4): ====
# '''Relatively inexpensive'''
# '''Easy to implant'''
# '''Easy to use'''
# '''Low mechanical failure rate'''

==== Disadvantages (3): ====

# '''Simulates a constant erection, may be difficult to conceal'''
# '''Does not increase penile girth'''
# '''Quality of erection decreases over time''' (due to loosening of scar capsule around device)

=== Inflatable ===

* '''Designed to approximate normal function more closely by permitting girth and length expansion during erection and penile flaccidity when not in use'''
* Consist of 2 hollow intracorporeal cylinders, each of which fills a corpus cavernosum; the cylinders are inflated with saline solution to produce penile rigidity during sexual activity and are deflated after intercourse.
* '''<span style="color:#ff0000">Subdivided into 2-piece vs. 3-piece devices</span>'''
** '''<span style="color:#ff0000">2-piece device</span>'''
***'''<span style="color:#ff0000">Consists of the two cylinders and a scrotal pump</span>'''.
**** '''Reservoirs in the proximal portion of the cylinders are prefilled with saline''' '''and preconnected to the pump via silicone tubing'''.
**** '''Pressing a valve mechanism''' in the pump transfers the solution from the reservoirs into the distal, inflatable portion of each cylinder.
**** '''Bending the cylinders down for several seconds activates a release valve''' that deflates the device by allowing the fluid to flow back to the reservoirs.
** '''<span style="color:#ff0000">3-piece device</span>''' 
***'''<span style="color:#ff0000">Consists of the two hollow cylinders, a scrotal pump, and a saline-filled reservoir.</span>'''
**** Silicone tubing connects the cylinders to the pump and the pump to the reservoir.
**** '''Repeatedly squeezing the pump''' transfers saline from the reservoir to the cylinders until adequate rigidity is achieved
**** '''Pressing a valve mechanism in the pump causes the fluid to flow back to the reservoir.'''
** Both devices are available in several widths and lengths and come with optional rear tip extensions to allow them to be tailored to each patient.
** '''<span style="color:#ff0000">Advantages of two-piece compared to three-piece (2):</span>'''
**# '''<span style="color:#ff0000">No need to implant a separate reservoir</span>'''
**#* Facilitates surgery and may be useful with patients in whom placement of the reservoir is extremely difficult because of colostomy, ileostomy, kidney transplant, or extensive pelvic surgery
**# '''<span style="color:#ff0000">Reaches full inflation with fewer squeezes of the pump</span>'''
** '''<span style="color:#ff0000">Disadvantages of two-piece compared to three-piece (3):</span>'''
**# '''<span style="color:#ff0000">Pump is very small and hard, making it difficult for patients to manipulate</span>'''
**# '''<span style="color:#ff0000">Implantation requires a larger incision of the tunica albuginea</span>'''
**# '''<span style="color:#ff0000">Feels and acts less like a natural erection</span>'''