The dorsal artery provides for engorgement of the glans during erection, whereas the bulbourethral artery supplies the bulb and the corpus spongiosum. The cavernous artery effects tumescence of the corpus cavernosum and thus is principally responsible for erection. The cavernous artery gives off many helicine arteries, which supply the trabecular erectile tissue and the sinusoids. These helicine arteries are contracted and tortuous in the flaccid state and become dilated and straight during erection. 
The venous constriction device is a device designed to compress the veins that drain blood flow out of the penis to keep blood in the penis. These devices may help individuals who have a "venous leak." In these individuals, although blood flow is coming into the penis, it is draining out at the same time and this persistent drainage prevents a fully rigid erection. These devices may be used with other forms of medical therapy, such as medications, injection therapy, or the vacuum device.
As men age they require more stimulation up front to get and maintain an erection firm enough for sex. Engaging in some foreplay either on you or on your partner is a great way to get your arousal levels up and get an erection that is firm enough for sex. Many men begin to rush the process of sex once they experience ED. They worry that they will lose their erection so they rush rather than go slow understanding that rushing will only make the problem worse.
There are risks to prosthetic surgery and patients are counselled before the procedure. If there is a post-operative infection, the implant will likely be removed. The devices are reliable, but in the case of mechanical malfunction, the device or a part of the device will need to be replaced surgically. If a penile prosthesis is removed, other non-surgical treatments may no longer work.
Erectile dysfunction (ED) related to compromise of the nervous system is an increasingly common occurrence. This may be due to the multifactorial nature of ED, the myriad of disorders affecting the neurotransmission of erectogenic signals, and improved awareness and diagnosis of ED. Nevertheless, neurogenic ED remains poorly understood and characterized. Disease related factors such as depression, decreased physical and mental function, the burden of chronic illness, and loss of independence may preclude sexual intimacy and lead to ED as well. The amount of data regarding treatment options in subpopulations of differing neurologic disorders remains scarce except for men with spinal cord injury. The treatment options including phosphodiesterase inhibitors, intracavernosal or intraurethral vasoactive agents, vacuum erection devices (VED) and penile prosthetic implantation remain constant. This review discusses the options in specific neurologic conditions, and briefly provides insight into new and future developments that may reshape the management of neurogenic ED.
Other factors leading to erectile dysfunction are diabetes mellitus, which is a well-known cause of neuropathy). ED is also related to generally poor physical health, poor dietary habits, obesity, and most specifically cardiovascular disease, such as coronary artery disease and peripheral vascular disease. Screening for cardiovascular risk factors, such as smoking, dyslipidemia, hypertension, and alcoholism is helpful.
However, in contrast, a recent systematic review of published studies, the authors concluded that overall, the addition of testosterone to PDE-5 inhibitors might benefit patients with ED associated with testosterone levels of less than 300 ng/dL (10.4 nmol/L) who failed monotherapy.  A limitation of existing studies are their heterogeneous nature and methodological drawbacks.
Organic ED involves abnormalities the penile arteries, veins, or both and is the most common cause of ED, especially in older men. When the problem is arterial, it is usually caused by arteriosclerosis, or hardening of the arteries, although trauma to the arteries may be the cause. The controllable risk factors for arteriosclerosis--being overweight, lack of exercise, high cholesterol, high blood pressure, and cigarette smoking--can cause erectile failure often before progressing to affect the heart.
Ginseng, specifically “red ginseng,” is known as the “herbal Viagra” that helps puts to rest men’s bedroom woes. Red ginseng is when the root has been steamed and then dried. The ginseng root is the part of the plant that is mostly used as a natural remedy when in its supplement form. However, the plant must be grown for a minimum of five years before it can be used. In a 2008 review, seven studies on red ginseng and ED, ranging in dosages from 600 to 1,000 milligrams three times a day, were found to provide evidence for the effectiveness of the herb in ED treatment.
A physical exam checks your total health. Examination focusing on your genitals (penis and testicles) is often done to check for ED. Based on your age and risk factors, the exam may also focus on your heart and blood system: heart, peripheral pulses and blood pressure. Based on your age and family history your doctor may do a rectal exam to check the prostate. These tests are not painful. Most patients do not need a lot of testing before starting treatment.