Male Erectile Response and Enhancement
In general, the majority of men can attain an erection after SCI either through the psychogenic (T11-L2) or reflexogenic (S2-S4) pathways, depending on the level and completeness of injury. However, these erections are often unreliable or inadequate for sexual intercourse with difficulties experienced in maintaining an erection (Alexander et al. 1993; Courtois et al. 1993). Treatments for erectile dysfunction (ED) in men with SCI have advanced considerably in recent years with the availability of phosphodiesterase type 5 inhibitors (PDE5i) taken as a tablet orally. However, other methods are still being utilized when oral medication is ineffective or unaffordable. There is stronger evidence for treatment of erectile dysfunction than other areas of sexuality in SCI, primarily due to the advent of the PDE5i and their effectiveness in this population.
Therapies for erectile dysfunction (ED) include:
- Oral medications, which indirectly relax the penile smooth muscle and enhance an erection attained by sexual stimulation, such as the oral phosphodiesterase 5 inhibitors [PDE5i] Viagra®, Levitra® and Cialis®
- Intracavernosal injectable medications, which directly relax the penile smooth muscle creating an erection (prostaglandin E1 penile injections [Caverject® or compounded] and other injectable combinations of papaverine and phentolamine)
- Topical agents for penile smooth muscle relaxation (prostaglandin, minoxidil, papaverine and nitroglycerine)
- Intraurethral preparation of prostaglandin E1 (MUSE®)
- Mechanical methods, such as vacuum devices and penile rings
- Surgical penile implants
- Behavioural methods (perineal muscle training)
- Psychological and sex therapy (non-medicinal) adjunct to medical therapies after SCI
All methods except penile implants are clinically reversible. The use of implantable sacral stimulators to assist an erection via stimulation of S2 and S3 anterior roots has not been well explored due to its limited use in those with complete SCI lesions (Brindley et al. 1989). The detrimental effects on erectile function of baclofen and baclofen pumps are noted, but they appear to be clinically reversible with baclofen discontinuation.
