The evaluation of the male with erectile dysfunction consists of three distinct parts, namely, a structured interview, physical examination, and adjunctive testing. While the role of the latter is debated for the general erectile dysfunction population, there are some patients who benefit from identifying a cause of the ED. All patients presenting for the evaluation of impotence should undergo a comprehensive history and a focused physical examination. The purpose of this approach is to define (1) that the patient suffers from sexual dysfunction and to determine the nature of this, (2) that the patient has adequate exercise tolerance to resume sexual relations, (3) that the patient does not have any conditions in his medical or surgical history that represent contraindications to specific therapies and (4) to seek out factors in the patient's medical surgical and sexual history that may indicate an etiology of his sexual dysfunction.
It is unknown what percentage of patients presenting to a urologist for nonsexual complaints ever get questioned regarding their sexual function. However, it has been estimated that only 30 percent of all men presenting to primary care physicians are asked questions regarding sexual function. The reason for this is most probably multifactorial, with both patient and physician factors playing a role. From a patient standpoint, it is widely appreciated that embarrassment and fear play a major role in a patient’s reticence to broach this subject. From a physician standpoint, factors interfering with initiating dialogue regarding sexual function include lack of physician time, lack of physician interest, lack of physician knowledge, and cultural and religious issues.
The history taking should begin with a brief survey of the patient demographics, including his partner's age and the duration of his relationship with his partner and the specific dynamics of that relationship. A brief inquiry as to the female partner’s menopausal status is also worthwhile. Furthermore, the dynamics in a homosexual relationship are different than that in a heterosexual one. History taking should then move to the medical and surgical history of the patient. Specifically, attention should be focused on vascular, neurological, endocrinological, operative and psychological issues that may represent risk factors for sexual dysfunction. While urologists, internal medicine physicians, and family practice physicians are not psychologists nor psychiatrists, a brief assessment of the patient's psychological status is important. Specifically, it is important to define if there are overt risk factors for psychogenic ED such as the patient being in his first relationship following divorce or following being widowed, whether he is having significant interpersonal difficulties with his partner, whether he has a significant external stressor load or the presence of an overt affective disorder. With reference to a patient's prior surgical history, defining the time of onset of erectile dysfunction with regard to the date of operation is important. Clearly, those operations most likely to interfere with erectile function are pelvic surgeries.
Obtaining a good medication history is important in sexual function evaluation. Many pharmacologic agents have been associated with erectile dysfunction, however, it is often difficult to determine whether it is the drug itself or the condition for which the patient is being treated that is the primary etiologic factor. Those medications that have been most frequently associated with ED include anti-hypertensives, psychotropic medications, medications with anti-androgenic activity and recreational drugs. It is worth noting that monoamine oxidase inhibitors represent an absolute contraindication to the use of systemic or intracavernosal alpha agonist therapy. The use of recreational drugs such as marijuana, cocaine, and heroine have been reported in the literature to induce erectile dysfunction. Paradoxically, cocaine is also a significant risk factor for priapism. While the effect of cigarette smoking on systemic vasculature is well-documented, it has not yet been clearly defined epidemiologically if cigarette smoking is an independent risk factor for erectile dysfunction. The chronic use of alcohol is associated with ED through several mechanisms including peripheral neuropathy, testicular dysfunction and hepatic dysfunction.
Obtaining a good sexual history requires practice. Firstly, it is important to define of which sexual dysfunction the patient is complaining. It is not uncommon for patients to confuse impotence with other sexual dysfunctions such as premature ejaculation, retarded orgasm, or even retrograde ejaculation. Defining a patient's (and partner’s) expectations and goals is also of value as some patients present purely to obtain information, others’ interest lies only in oral therapy while others want ”whatever it takes“ to resolve their problem.
With regard to erectile dysfunction (ED) the key questions include duration of ED, degree of ED, erectile spontaneity, erectile sustaining capability, early morning/nocturnal erectile function, timing of last sexual intercourse, and whether the erectile dysfunction is situational or not. The definition of erectile dysfunction is “the consistent inability to obtain and/or maintain an erection sufficient for satisfactory sexual performance,” therefore, consistency of ED is important. While the definition of consistency is somewhat debatable most authorities believe that a man with the three-month history of ED warrants treatment. Defining whether the patient has primary problem with spontaneity or sustaining capability may give the clinician an idea as to the etiology of the problem. One of the great myths in sexual medicine is that the presence of a rigid early morning erection indicates psychogenic ED. This is a false concept, as many men with significant arteriogenic ED wake up with good erectile rigidity. The presence of good early morning erections is suggestive only of adequate venocclusive function. The hallmarks of psychogenic ED are sudden onset erectile problems and intermittency of function, therefore assessing these factors by history is also important. Furthermore, defining if the erectile dysfunction is situational, such as a discrepancy in erectile function between partners or between a partner and masturbation, may help support a diagnosis of psychogenic ED.
Even in patients who present with erectile dysfunction, questions regarding ejaculatory function, orgasmic function and libido are important. The goal of the clinician should be to allow the patient to return to satisfactory sexual relations, and while resolution of erectile dysfunction is an important start, addressing and treating any secondary sexual dysfunctions such as premature ejaculation and/or loss of libido will likely be necessary to maintain patient satisfaction. It is not uncommon for patients with long-standing ED to have a significant reduction in their sex drive and furthermore, they are also at risk for developing premature ejaculation particularly if they have problems with maintenance of erectile rigidity. Correcting a patient's erectile dysfunction may have a positive effect on the patient’s secondary premature ejaculation.
There are a number of validated questionnaires available that obtain information regarding a patient’s sexual function. These include the International Index Of Erectile Function (IIEF), which is the questionnaire routinely used at the Sexual Medicine Program at New York Presbyterian Hospital. More valuable to the primary care clinician is the Sexual Health Inventory For Men (SHIM), a five question instrument that can easily define the presence of ED. In routine clinical practice whether these instruments are utilized or not is a matter of style, however, even if the questionnaires are used, they do not circumvent the need for face-to-face discussion as outlined above.
The physical examination of the patient presenting with sexual dysfunction should focus on (1) secondary sexual characteristics, (2) abdominal examination, (3) major pulse examination, (4) S2-4 neurological assessment, and (5) external genitalia examination. Abdominal examination should focus on the assessment for an abdominal aortic aneurysm. It has been estimated that approximately 1 percent of all men presenting for the evaluation of erectile dysfunction will have an enlarged abdominal aorta. The major pulses should be assessed, specifically, the femoral and popliteal pulses as these are excellent markers for systemic atherosclerotic disease. In cases where there is a concern regarding neurogenic ED, an assessment of S2-4 neural pathways is indicated. An assessment of the bulbocavernosus reflex (BCR) is only of significant benefit if the reflex is positive as 30% of neurologically intact patients will have a BCR.
Examination of the penis in this patient population should focus primarily on the presence of Peyronie's disease plaques. A good assessment of the integrity of the erectile tissue may be gained from stretching the penile shaft. In patients with significant corporal fibrosis, such as in men with poorly controlled diabetes, there is significant diminishment in the ability of the penis to stretch, in contrast to young patients with psychogenic or mild arteriogenic ED where penile stretch capabilities are normal. Examination of the testicles is aimed primarily at defining the presence or absence of masses and also to ascertain the testicular volume and consistency. All men over the age of 40 years and those with lower urinary tract symptoms undergo digital rectal examination for prostate assessment.
Obtaining basic hematologic and biochemistry laboratory analyses in men with ED has been recommended by the NIH consensus panel. The screen should include serum glucose estimation in an effort to rule out the presence of diabetes. Many of the patients seen for ED will already have had such laboratory testing by their primary care physician and will not need to have this repeated. Assessment of liver function tests and thyroid function tests are best reserved for those patients who manifest symptoms and or signs suggestive of hepatic or thyroid dysfunction.
One of the great controversies in sexual medicine revolves around the definition of an adequate hormonal assessment of the patient with ED. There is an absence of medical literature that clearly answers this question. At the Sexual Medicine Program at New York Presbyterian Hospital a single early morning total testosterone level is drawn. Most significant endocrinopathies that are of concern will generally manifest with a low serum testosterone level. In the presence of a low total testosterone level we repeat the blood work to include a total and free testosterone level, combined with an LH and a prolactin level. Most would agree that men presenting with classic symptoms or signs of hypogonadism should undergo a full hormone screen as outlined above at the outset.
In routine clinical practice the majority of men presenting with erectile dysfunction do not require any further testing. However a number of investigations exist which are available to aid the clinician in assigning a cause to the patient’s ED. Such investigations include (1) vascular testing such as duplex ultrasound and dynamic infusion cavernosometry/cavernosography, (2) neurological testing such as a biothesiometry, somatosensory evoked potentials and pudendal electromyography and (3) nocturnal penile tumescence and rigidity analysis. Much debate has been conducted on the indications for such investigations. In my practice, adjunctive investigations are reserved for the following groups of patients: (1) patients who are potentially curable: this group includes patients with a high risk for primarily psychogenic ED, patients with endocrinopathy, young males with traumatically induced pure arteriogenic erectile dysfunction and young males with isolated crural venous leak, (2) patients with penile curvature prior to undergoing penile reconstructive surgery and (3) medicolegal cases.
There is also a significant variability in the utilization of psychological assessment during evaluation of the male with ED. Certainly, any patient who presents with an obvious untreated psychiatric disorder should be directed to the appropriate expert. Patients who are routinely sent for psychological evaluation and management in my practice are those who have an overt complex psychological risk factor for sexual dysfunction and those with significant interpersonal difficulties either arising from or leading to their sexual dysfunction.
Two investigations that are frequently used by clinicians in the office setting in evaluation of the impotent male include biothesiometry and office injection testing. The former testing utilizes an electronic device for the assessment of penile vibratory thresholds. Although nomograms have been published for appropriate penile sensory thresholds, the value of routine biothesiometry is debated. Office injection testing involves the administration of intracavernosal vasoactive agents to the ED patient and the assessment of the degree of erectile rigidity in response to this agent. Some clinicians use this test to assess if the patient has psychogenic ED (the development of a fully rigid durable erection) or venogenic ED (failure to obtain a penetration rigidity erection), however, given the fact that approximately 30% of men with normal erectile hemodynamics will fail to obtain a penetration rigidity erection in response to a single dose of intracavernosal vasoactive agent, drawing conclusion from this test may be flawed. A positive response to this test, that is the development of the durable rigid erection, indicates that the patient’s venocclusive mechanism is intact.
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