Penile implants

Hypersensitivity to the drug conditions that might predispose patients to priapism (eg, sickle cell anemia or trait, multiple myeloma, leukemia) patients with anatomical deformation of the penis patients with penile implants (intracavernosal) use in women, children, or newborns use in men for whom sexual activity is inadvisable or contraindicated for sexual intercourse with a pregnant woman unless the couple uses a condom barrier. 

Calcitonin gene-related peptide (CGRP) induces a dose-related increase in penile arterial inflow, cavernous smooth muscle relaxation, cavernous outflow occlusion, and an erectile response. CGRP plus PGEj may be an alternative to penile implants in selected patients. 

Contraindications Conditions predisposing to anatomic deformation of penis, penile implants, priapism... 

Erectile dysfunction, that is, the inability to maintain penile erection for the successful performance of sexual activity, has both organic and psychogenic causes, including as a sequelae to prostatic surgery. Erectile dysfunction is estimated to affect up to 30 million men in the United States. Previous therapies have included penile implants, and intrape-nile injections of alprostadil (see p. 420). Sildenafil [sil DEN a HI], the first oral drug approved for the treatment of erectile dysfunction in males, was introduced in early 1998. 

Some selective dopamine D4 agents are now being investigated for treatment of ED. Vacuum devices and penile implants are also available. 

Prosthetic Devices. In urology, a prosthetic device almost always refers to a penile implant, which is a treatment option for men with erectile dysfunction for whom other treatments have failed. About 30 million men in the United States have erectile dysfunction, and about one-third of them do not respond to other treatments. Implantation requires a surgical procedure, which is why other options are tried first. Implants have several advanfc es. They do not require the doctor visits for prescriptions and monitoring that are necessary with pills, creams, suppositories, and injections, and they are available for immediate use and are aesthetically pleasing because they prevent the penis from contracting when cold. 

Nukui, F, S. Okamoto, M. Nagata, J. Kmokawa, and J. Fukui. 1997. Comphcations and reimplantation of penile implants. Int J Urol 4 52-54. 

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. 

Taking a product from development to successful PMA usually requires at least seven years. The average time to FDA approval once all required testing is completed and submitted for review is 2-5 years [2. Lewin, N. Faster approvals seen for drug and device combination products. BBI Newsletter 2003 26(9).] Given the time and expense involved, a company must try to predict whether their product, nearly a decade in the future, will fill a significant market need and be profitable. Examples of PMA devices approved in the past include an artificial urinary sphincter a penile infiatable implant and electro-optical sensors for in vivo detection of cervical cancer. [3. http //www.fda.gov/cdrh/devadvice/pma/ (accessed October 2005).]... 

Urologists are continuing to develop their surgical skills to achieve improvements in appearance, function, and sensation. Internal penile pumps remain a popular choice versus flexible implants, vasodilator pills, or external pumps and creams more than 250,000 men have already chosen to have such a device implanted. Surgeons will continue to correct birth defects and repair urogenital trauma. Their aim is to restore function or at least preserve it. 

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). 

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. 

It is now well identified that bacteria connect to solid supports to shape structured communities called biofilms, also known as biopolymer matrix-enclosed microbial populations adhering to each other and/or surfaces [111]. Biofihns occur on both living and inert supports in all environments [112]. They influence various industrial and domestic areas [113] and are accountable for a broad range of human diseases [111], In view of the ever growing number of implanted patients, biofilm-linked infections of indwelling medical devices are more predominantly a foremost public health issue. Various examples of implants that can be inflated by biofilm formation are mechanical heart valves, catheters, pacemakers/defibriUators, ventricular assist devices, vascular prostheses, coronary stents, neurosurgical ventricular shunts, cerebrospinal fluid shunts, neurological stimulation implants, ocular prostheses, inflatable penile, cochlear, joint prostheses, fracture-fixation devices, breast, and dental implants and contact lenses, intrauterine contraceptive devices [114-116]. 

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. 

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