Erectile Dysfunction

Introduction 
The problem of an inadequate erection is probably one of the biggest issues a man confronts. It has been listed in the top ten health concerns for men for 2006 and is one of the main complaints for which many men will seek health care. Most men experience erectile problems on occasion, but erectile dysfunction (ED) is the most common. ED is defined as “the persistent failure to develop and maintain erections sufficient rigidity for penetrative sexual intercourse.” ED is further defined as the inability to achieve and maintain an erection adequate for intercourse to the mutual satisfaction of the man and his partner. It is important to remember that both partners are affected by ED. Of course, men have other kinds of sexual problems including lack of desire caused by low testosterone, Peyronies Disease, which is a curvature of the penis making penetration difficult or impossible, and ejaculation difficulties. However, ED is the most common. It affects 35 percent of men age 40 to 70, and risk increases with increased age and with other concurrent diseases.

The best way for a man to begin solving erectile problems is by reading about men’s sexual system -- anatomy, physiology, disease, drugs, diagnosis, and treatment. Some of the problems may be solved simply but others may involve cardiovascular disease and require a visit to your family doctor, an urologist, and in some cases a cardiologist. We often consider the penis as a barometer of cardiovascular health. In either case, we encourage you to become an educated health care consumer, which should help you regardless of the cause or cure for your problem.

Anatomy of the Penis
The anatomy of the penis is complex. It is comprised primarily of two cylinders of sponge-like vascular tissue that fill with blood to create an erection. Blood is pumped from the heart into the penis under great pressure and a series of valves keep it in the penis to maintain the erection. A third cylinder is the urethra, a tube that carries the urine and the ejaculate. The knobby head of the penis is called the glans. Blood flows to the penis by two very small arteries that come from the heart and then the Aorta. These arteries are the same size as the arteries to your finger. The main problem that causes ED is that the lining of theses blood vessels becomes dysfunctional and the blood can not get to the penis. This known as Endothelial Dysfunction, or the real “ED.” The other major problem is leakage of blood from the penis into the veins around the penis, which is called a venous leak. This is very common and is similar to a hole in a tire. The larger the hole, the more air that needs to be pumped into the tire to keep it hard!

Penile Enlargement
The enlargement of the penis by surgery is twofold. The procedure to lengthen the penis is done by cutting the suspensory ligament. This procedure gives the appearance of a longer penis but does not actually increase its length. It also makes the penis more unstable during intercourse and, in due course, more susceptible to injury. The other method of enlargement is by liposuction of tissue from one part of the body and injecting it around the penis to create a fatter penis. This gives the appearance of a fat, wide penis but not longer. These procedures are not recommended and have very high complication rates.

Physiology of Erection: How the Penis Works
The creation of an erection is an extremely complicated cascade of events that requires many different things to happen. There are numerous chemical transmitters involved in this including epinephrine, norepinephrine, acetylcholine, prostaglandins and nitric oxide. The exact mechanism by which erection occurs is still unclear but we do know that the neural input from the brain is extremely important. Reflex erections, as seen in people with cord damage such as paraplegics, are often poor erections and not sustainable for prolonged periods of intercourse.

An erection occurs when the nervous system activates a rapid increase in blood flow. The vascular muscle in the spongy area becomes engorged with blood and the outflow of blood is cut off. An erection can occur as a reflex as we see in spinal cord patients, or can be caused by psychogenic (originating in the mind) stimulation. Numerous sexual stimuli are processed by the brain and transmitted to the penis via the nervous system.

In order to increase the size of an erection, there must be an increase in blood flow and, at the same time, the blood has to be prevented from leaving the penis.

Causes of Erectile Dysfunction

The Effects of Disease States and Drugs

  • Cardiovascular Disease is the most common cause of ED and is due to endothelial dysfunction. Studies have demonstrated that two million people have heart disease but have no symptoms, and one out of four men with no risk factors will die suddenly of a cardiovascular event. Other studies indicate that ED may be present for 2-3 years prior to the diagnosis of heart disease.  
  • Smoking is one of the greatest health enemies and is responsible for over 400,000 deaths per year. Smoking causes endothelial dysfunction, which causes ED. I firmly believe that if manufacturers added a warning to cigarette labels that smoking will make erections go away, no man would smoke.
  • Diabetes is the most common cause of sexual dysfunction in men. It has been estimated that up to 50-75 percent of diabetic men have erectile dysfunction, because diabetes causes endothelial dysfunction. Diabetics must pay attention to diabetic neuropathy -- the loss of vibratory sensations of the lower extremities. With this disease, there is always the possibility of peripheral neuropathies. Other diseases that are associated with peripheral neuropathies include chronic renal failure, carcinomas, rheumatoid arthritis, hypothyroidism, herpes zoster, anemias, breathing problems, such as chronic obstructive pulmonary disease, as well as a long list of hereditary neuropathies. 
  • Hypertension (HTN) or high blood pressure is one of the most common health conditions. HTN is the second most prevalent disease in men with ED. HTN causes endothelial dysfunction, which leads to ED. However, the treatment of HTN can also cause ED.
  • Enlarged Prostates or BPH can be the cause of ED as well. Treatment of the prostate disease can reverse ED but cause ejaculatory disorders.
  • Prostate Cancer as well as the treatment of prostate cancer can lead to ED.
  • Dyslipidemia or abnormal concentrations of lipids in the blood. These high concentrations of bad cholesterol will cause endothelial dysfunction, which leads to ED.
  • It is estimated that fifty percent or more of men with Multiple Sclerosis have erectile dysfunction. Bladder dysfunction can be also be associated with the erectile dysfunction in multiple sclerosis. 
  • Parkinson's disease and temporal lobe abnormalities are risk factors for erectile dysfunction. 
  • Stroke and alcoholism create a very high risk because of damage to the testicles and the resulting decrease of testosterone in the body. 
  • Aging is a common risk for erectile dysfunction, often related to a decrease of male hormones and endothelial dysfunction. The Massachusetts Male Aging Study indicated that 50 percent of men age 40-70 have a minimal, moderate or severe degree of erectile dysfunction.
  • Chronic renal insufficiency is another potential factor. Many drugs used to treat the type of high blood pressure associated with chronic renal insufficiency can cause erectile dysfunction, and many drugs are, by themselves, the culprit.

Drugs That Cause Impotence
Recreational drugs are a major cause of erection problems and the number one problem drug is tobacco. Experiments show that even two cigarettes will markedly decrease the blood flow to the penis if smoked before sex. Marijuana, cocaine and alcohol are also big causes of erection problems.
Prescription drugs are also big culprits, especially blood pressure drugs.

The major problem drugs include: 

  1. Estrogens used in men with prostate cancer 
  2. Antiandrogens (flutamide) used in men with prostate cancer 
  3. Lupron - prostate cancer drug 
  4. Proscar - for men with enlarged prostates, can decrease the volume of ejaculate 
  5. Diuretics - used for men with heart disease and hypertension 
  6. Methyldopa - older treatment for blood pressure 
  7. Beta blockers - for heart disease and hypertension 
  8. Calcium Channel Blockers- newer treatments for hypertension 
  9. Tranquilizers 
  10. Decongestants 
  11. Seizure Medications 
  12. Drugs to lower Cholesterol 
  13. Cimetidine - a drug for ulcers 
  14. Digoxin - a drug for heart failure 
  15. Antidepressants
  16. Antihistamines

Other causes of ED include surgical treatments for prostate problems, bladder removal for cancer, urethral stricture, urinary surgery, carcinoma of the penis, priapism, renal transplantation, colon surgery, radiation, lumbosacral surgery, penile amputations, and penile surgery in children to correct congenital problems.

History and Physical Exam
The single most important part of the evaluation of male sexual dysfunction is the patient's history, with particular attention to sexual history, cardiovascular history, history of diabetes, smoking, medications and family history. A sexual history is often difficult for the inexperienced practitioner, but, again, is extremely important in determining the cause of the problem. Many subject areas should be explored while taking the history of a patient with sexual dysfunction. Specific topics should include cardiovascular disease or surgery, genitourinary disease or surgery, testicular damage, prior testicular torsion, penile surgery, or scrotal surgery such as for hydrocele or spermatocele. In addition to the above, diet and exercise tolerance should be explored as well.

The physician should ask the patient about any symptoms of cardovascular disease such as hypertension, elevated cholesterol, heart attack, intermittent claudication or blood vessel disease to the legs, and specifically, about any diseases such as Lerich syndrome. This last condition is a pattern of buttocks claudication in young men who lose their erections, which is a common cause of erectile dysfunction in men with arterial insufficiency. 

It is also important to document any known endocrine problems. The most common such cause of erectile dysfunction is diabetes mellitus, but there are other endocrine-based causes including hyperprolactinemia, which is an elevated prolactin in the serum. This condition can be caused by pituitary adenomas and creates a very specific type of erectile dysfunction where a man loses desire for sex, but maintains good function of the erectile mechanism.

Any history of debilitating diseases such as cancer should be noted, along with treatments such as chemotherapy or radiation. Neurologic diseases, including multiple sclerosis, strokes, cord damage or other cord problems should also be discussed. Vascular surgeries, neurologic spine or inguinal surgery should also be explored for evidence of damaged blood vessels, damaged innervation, or loss of the sympathetic nerve control.

The physician should ask about sleep disorders, such as sleep apnea syndromes, and about psychologic problems, along with the names of any drugs used to treat them. A marital or relationship history is important and should include the frequency of intercourse and the frequency of ejaculation. Attention should be paid to any changes in mental status. Other questions should focus on the frequency of nocturnal erections, whether a patient wakes up in the morning with an erection, and whether the erections are different when not having intercourse, during oral sex or masturbation, and how they compare to one another.

All medications should be reviewed, including any over the counter products. Tobacco use, including the amount and length of time that the patient has smoked, are important to note. Any alcohol or recreational drug use, especially marijuana or cocaine, should also be documented. The physician should also attempt to ascertain and note the level of interest of the patient's partner in solving the erectile dysfunction problem.

Sexual dysfunction questions should also cover significant personal problems that may exist, such as a stressful job situation, impending divorce, separation, or sex with multiple partners. Also, If the patient has seen other physicians about impotence, it is important that the prior treatment and workup be documented and discussed.

In our clinic, we rate an erection on a scale of one to ten, with ten being rock hard and five being adequate for penetration or "stuffable", but buckles back. We also ask how long intercourse lasts and does it usually end with an ejaculation? What is the character and frequency and what is the force of ejaculation? Is there an odor to the ejaculate? How often does the patient have intercourse? What is the level of interest in sexual relations or how often does this happen? Does the patient's partner provide enough stimulation to allow an adequate sexual relationship to occur? We also discuss alternative sexual measures.

The physical examination should focus on overall body habits, whether the patient is obese, for example, and on such secondary sexual characteristics as breast swelling and enlargement (called gynecomastia), which indicates a hormonal or drug cause of the erectile dysfunction. An examination of the genitalia should include determining the presence or absence of plaque-like formations in the corporal bodies indicative of Peyronie's disease as well as the anatomy of the meatus and the urethra. Examination of the testicles should include the size, location, presence or absence of masses and the presence or absence of hernias. The neurologic examination should focus on penile sensation as well as obtaining a bulbocavernosus reflex. Finally, the pulses should be palpated for evidence of vascular dysfunction.

Several tests should be included in the workup for ED, some are simple and inexpensive. Urinalysis to look for the presence of blood or protein is easy, noninvasive, inexpensive and can be performed at any urologist office. A full assay of blood work includes tests for PSA, testosterone, prolactin, and cholesterol levels.

Treatment
The most important part of the treatment for ED is to address the cause. We must address the cause and not just hand out medication. For any treatment to be effective, the patient must adjust any contributing lifestyle factors; therefore, lifestyle modification is a corner stone to treatment. Also, the patient must have any contributing disease process such as diabetes, HTN or elevated cholesterol levels under control.

After we complete a history, physical examination, and laboratory investigation, and have a good handle on the diagnosis, we talk with the patient about treatment options. There are so many options available; the question becomes which of the many is best for each patient: vacuum pumps, intraurethral medications, venous constriction devices, penile injections, penile prostheses or oral therapy?

The best treatment is goal-directed so that the options are specific to the needs of the patient and his partner, and will be based on how much the patient wants to do about his current problem. Some of the factors to consider: 

  • The patient’s age. 
  • His total health status. 
  • Does the patient have good functioning of his lower and upper extremities? 
  • Does he have a very willing and active sexual partner? 
  • Does the patient have numerous sexual partners?
  • Is the patient’s partner involved in the decision making process? 
  • What are the goals of therapy?

A great deal of effort goes into educating the patient so he can make an informed decision and we also tailor the workup and treatment to the patient’s specific needs. The patient is first instructed in the use of oral therapy and then, if a trial of oral therapy is successful, we stop at this point. Today there are many options for oral therapy: Viagra®, Levitra ®, or Cialis ® can be used in most patients.

If the patient continues to have problems (a fair percentage of men will), we then proceed to educate the patient about the variety of other therapies. He may choose one of the many minimally invasive therapies, such as a vacuum erection device that can be very attractive for an older patient concerned about cost, or he may choose a penile injection program. Once oral therapy is proven ineffective, we educate the patient next about multiple agents and combinations of them that are currently available for penile injection including Papaverine, papaverine with phentolamine, papaverine with phentolamine and prostaglandin, or prostaglandin alone in the form of Caverject or Edex. Information about the cost of each type of injection and their proper use is shared in detail. Many men are somewhat hesitant about the use of penile injections and it often takes a long period of discussion and counseling to ease their minds. They have to understand that sticking a needle into their penis is not nearly as painful an event as one would imagine.

Penile Implants
Penile implants are another option. The latest penile implant technology is a dramatic improvement over what was available in the past. The newest devices are much more reliable and have a much lower incidence of infection, especially since they are now combined with antibiotic coatings to prevent infection. Before proceeding with an implant, we conduct a full investigation to be sure that no other less-invasive treatment alternatives are available or appropriate. At that point, we explain the details of vascular surgery as well as some of the diagnostic imaging modalities available to insure successful surgery, including color duplex ultra-sound evaluation.

Vacuum Erection Devices
The vacuum erection device is a plastic cylinder that is placed around the penis. When negative pressure is applied the penis becomes rigid. A rubber ring traps the blood in the penis and keeps the penis rigid for periods of up to thirty minutes. Ejaculation is possible while using the device.

These devices are made by a number of manufacturers and are available at several levels of sophistication, from manual pumps to battery-operated devices. The devices are reusable and have a very high satisfaction rate. The major drawback is that the cumbersome device is likely to cause loss of sexual spontaneity. One of the more common partner complaints is that the penis is cold and the rigidity is less than a normal erection. In older female partners, vaginal dryness and stenosis (narrowing) may make penetration difficult. Overall, however, these devices are excellent and are widely used. Most insurance companies will reimburse patients for them.

Posted January 2007