A man has erectile dysfunction when his penis has regularly failed to give an erection that has been good enough to achieve or maintain sexual penetration.
Most men at some point experience some difficulty with their penis becoming hard, or with maintaining an erection, but this is not erectile dysfunction, which is considered a disorder only if satisfactory sexual performance has been impossible on a persistent number of occasions for some time.
Doctors may look for symptoms to have persisted for at least three months before investigating them further and considering a diagnosis of erectile dysfunction needing treatment.
There is a simple test to offer some suggestion that the problem may have a medical cause rather than a psychological one – men with psychogenic erectile dysfunction usually have normal erections during sleep and as they wake up in the morning, whereas an organic cause will often prevent these erections.
Known as the ‘postage stamp test,’ it checks for the presence of nighttime erections – of which men usually have three to five a night – by seeing if postage stamps applied around the penis before sleep have snapped off overnight.
Other tests of nocturnal erection are the Poten test and Snap-Gauge test. These methods provide limited information, however, and simply lead the doctor in a diagnostic direction.
It is always worth talking to your doctor about problems with erection because they can be the earliest signal of atherosclerotic disease – narrowing of the arteries, which can lead to heart disease.
“Talk with your doctor about a broken sex life, and you might be able to prevent a broken heart.”
There are no formal tests to diagnose erectile dysfunction. Some blood tests are generally done to exclude underlying disease, such as hypogonadism and prolactinoma. Impotence is also related to generally poor physical health, poor dietary habits, obesity, and most specifically cardiovascular disease such as coronary artery disease andperipheral vascular disease.
Duplex ultrasound is used to evaluate blood flow, venous leak, signs of atherosclerosis, and scarring or calcification of erectile tissue. Injecting prostaglandin, a hormone-like stimulator produced in the body, induces erection. Ultrasound is then used to see vascular dilation and measure penile blood pressure.
Tests such as the bulbocavernosus reflex test are used to determine if there is sufficient nerve sensation in the penis. The physician squeezes the glans (head) of the penis, which immediately causes the anus to contract if nerve function is normal. A physician measures the latency between squeeze and contraction by observing the anal sphincter or by feeling it with a gloved finger inserted past the anus.
It is normal for a man to have five to six erections during sleep, especially during rapid eye movement (REM). Their absence may indicate a problem with nerve function or blood supply in the penis. There are two methods for measuring changes in penile rigidity and circumference during nocturnal erection: snap gauge and strain gauge. A significant proportion of men who have no sexual dysfunction nonetheless do not have regular nocturnal erections.
This test uses electromagnetic vibration to evaluate sensitivity and nerve function in the glans and shaft of the penis.
Technique in which fluid is pumped into the penis at a known rate and pressure. It gives a measurement of the vascular pressure in the corpus cavernosum during an erection.
Cavernosography measurement of the vascular pressure in the corpus cavernosum. Saline is infused under pressure into the corpus cavernosum with a butterfly needle, and the flow rate needed to maintain an erection indicates the degree of venous leakage. The leaking veins responsible may be visualised by infusing a mixture of saline and x ray contrast medium and performing a cavernosogram. In Digital Subtraction Angiography (DSA), the images are acquired digitally.
This is similar to magnetic resonance imaging. Magnetic resonance angiography uses magnetic fields and radio waves to provide detailed images of the blood vessels. Doctors may inject a “contrast agent” into the patient’s bloodstream that causes vascular tissues to stand out against other tissues. The contrast agent provides for enhanced information regarding blood supply and vascular anomalies.