Venous leak may result from smooth muscle damage in the penis. Nerve messages from the brain or spinal cord do not reach the penis. If nerve stimuli do not reach the penis, an erection problem may occur. Some diseases can cause this problem, including diabetes, multiple sclerosis, and Parkinson's disease. Injuries or surgery to the genitals or pelvic area also can damage the penile nerves.
Diabetes can damage both the nerve and blood supply to the penis.
ED may be the first sign of diabetes or it can develop years after diagnosis. More than half of men with diabetes develop ED within 10 years of diagnosis. Most men with ED resulting from diabetes will respond to ED treatment options. Men Treated for Prostate Cancer Men who have been treated for prostate cancer with radiation therapy or a type of surgery called radical prostatectomy often develop ED as a side effect of treatment. Less Common Causes of ED Hormonal problems.