Spinal Cord Injury The nature of ED caused by spinal cord injury (SCI) is dependent on the acuity and location of the injury. Estimates of the preservation of erectile function vary widely, and are as high as 95% for reflexogenic erection.
Erections in men with SCI are characterized as reflexogenic when the stimulus is tactile or psychogenic when visual, auditory, or memory serve as the stimulus. Since erections are the result of parasympathetic output to the penis arising from S2 to S4, reflexogenic erection is maintained in suprasacral injuries or those not involving the lower motor neurons (LMN).
Cerebrovascular Accidents Cerebrovascular accidents (CVA) are another important cause of sexual dysfunction and, specifically, ED. As with other neurological diseases, the pathophysiology of ED in these patients is multifactorial and related to the physical, psychological, and social consequences of stroke. Sexual complaints in stroke patients include the loss of libido, frequency of sexual intercourse, ED, and sexual satisfaction.
These complaints are most attributable to interpersonal variables, such as the inability to discuss sexuality with a spouse or changed attitude toward sex, but the fear of impotence is a significant variable. Erectile dysfunction increases from 36% prestroke to 76% poststroke, and is associated with the degree of depression poststroke.
In a study that specifically assessed ED in stroke patients, approximately half of stroke patients reported ED.
A more important finding in this study was that preexisting diabetes, hypercholesterolemia, obesity, and smoking increased the prevalence of ED after stroke. The neurogenic component of ED in stroke patients is complex due to the various central structures involved in erectile physiology and the complexity of stroke distributions. Only one study to date has attempted to associate lesions on MRI with sexual dysfunction. Erectile dysfunction was only weakly associated with lesions involving the right pons.
While the specific nature of neurological insults that determine ED in stroke patients is yet to be determined, it is evident that psychosocial factors are an important determinant of sexual dysfunction after stroke.