Erectile Dysfunction Workup
- Author: Edward David Kim, MD, FACS; Chief Editor: Edward David Kim, MD, FACS more...
Approach Considerations
The laboratory investigation for erectile dysfunction (ED) depends on information gathered during the interview. Laboratory testing is necessary for most patients, although not for all. Based on the results of these studies, the physician should be able to determine the medical status of the patient, to identify and characterize the type of dysfunction, and to determine the need for such additional testing as penile or pelvic blood flow studies, nocturnal penile tumescence testing, or other blood tests.
Imaging studies are rarely performed, except in situations in which pelvic trauma or surgery has occurred.
The patient's needs, expectations, and priorities should be discussed in order to decide about further management or referral.
Evaluation of Hormonal Status
According to an American College of Physicians (ACP) guideline, the evidence regarding the utility of hormonal blood tests in identifying and affecting therapeutic outcomes for treatable causes of ED was inconclusive. The ACP does not recommend for or against routine use of hormonal blood tests or hormonal treatment in the management of patients with erectile dysfunction. Clinicians should individualize decisions to measure hormone levels based on the patient’s clinical presentation.
Patients who express a loss of libido, depression, or any signs of diminished secondary sexual characteristics should have an endocrine evaluation. At minimum, this should consist of measuring morning serum testosterone levels.
The relative merits of measuring total, free, and bioavailable testosterone levels and serum hormone–binding globulin are controversial. When screening for hypogonadism, measurement of total and free testosterone levels to investigate the hypothalamic-pituitary-gonadal axis is recommended. Because testosterone levels peak at approximately 8 am; therefore, a morning level should be checked whenever possible. Free or bioavailable testosterone is an important component because this is the testosterone that is usable. The remainder is attached principally to serum hormone–binding globulins.
Measurement of luteinizing hormone (LH) may be helpful. LH levels vary according to the body's need for testosterone. The hypothalamus regulates testosterone levels by releasing or inhibiting LH-releasing hormone, which acts in the pituitary to produce LH. A high LH level associated with a low testosterone level implies primary testicular (Leydig cell) failure. Conversely, a low LH level associated with a low testosterone level suggests a central defect.
In some instances, prolactin levels may be helpful as well. A serum prolactin level is obtained if the patient has evidence of pituitary hyperfunction (eg, from a pituitary tumor), and in documented cases of low serum testosterone levels.
A serum thyroid-stimulating hormone (TSH) evaluation is appropriate in select patients.
Blood Studies
Additional useful screening studies include the following:
- Hemoglobin A1c
- Serum chemistry panel
- Lipid profile
These studies should be considered unless the patient has had them performed recently and the results are available.
Measurement of prostate-specific antigen levels may be appropriate, if the patient is a candidate for prostate cancer screening. Such screening is controversial, however, and should be performed only after reviewing its risks and benefits with the patient. See Prostate Cancer for more information on this topic.
Urinalysis
Performing a urinalysis is recommended. The presence of red blood cells (RBCs), white blood cells (WBCs), protein, or glucose can be important clues to a genitourinary disorder.
Injection of Prostaglandin E1
One of the most common tests used to evaluate penile function is the direct injection of prostaglandin E1 (PGE1) into the corpora cavernosa (see the images below). If the penile vasculature is normal or at least adequate, an erection should develop within several minutes. The patient and the clinician can judge the quality of the erection. If successful, this test also establishes penile injections as one possible therapy.
A vasodilator such as prostaglandin E1 can be injected into one of the corpora cavernosa. If the blood vessels are capable of dilating, a strong erection should develop within 5 minutes. 
Erectile dysfunction. This diagram depicts a cross-section of penile anatomy and is used to instruct patients in the technique of administering intracorporeal medications. Biothesiometry
The sensitivity of the skin of the penis to detect vibrational stimuli (ie, biothesiometry) can be used as a simple nerve function office screening test, but is infrequently indicated. This involves the use of a small electromagnetic test probe placed on the right and left sides of the shaft and on the glans. The vibrational amplitude is adjusted until the subjective sensory threshold is reached, which is determined by questioning the patient (see the image below).
The presence of normal skin sensation adequate to produce an erection is measured with this device. A series of these tests determines the average vibrational sensory threshold in each location; these are then compared to reference range standards for the patient's age group. Although this test does not directly measure the erectile nerves, it serves as a reasonable screening for possible sensory deficit and is simple to perform. Formal nerve conduction studies, such as bulbocavernosus reflex latency time, are reserved for very select situations.
Ultrasonography
Vascular function within the penis can be evaluated with duplex ultrasonography. In this procedure, blood flow in the cavernosal arteries within the corpora is measured before and after the intracavernosal injection of a test dose of a standard vasodilator, such as 20 mcg of PGE1.
There is some variation in the criteria for evaluating the study results. A peak systolic velocity below 25 cm/s is generally agreed to indicate arterial insufficiency. The proposed value for the lower limit of normal ranges from 25-35 cm/s, but a peak systolic velocity of 35 cm/s or higher clearly rules out arterial insufficiency. End-diastolic velocity serves as a proxy for venous outflow; a velocity of 5 cm/s or less when the penis is at full rigidity indicates the absence of abnormal venous leakage.
Ultrasonography of testes and transrectal ultrasonography
Ultrasonography of the testes may help in disclosing abnormalities in the testes and epididymides, but this study is rarely indicated. Transrectal ultrasonography can disclose abnormalities in the prostate and pelvis that may interfere with erectile function.
Angiography
Angiography is useful if the patient is a potential candidate for some type of vascular surgery. Young men with traumatic vascular injuries resulting in ED are candidates for this study because they may qualify for a vascular reconstruction.
Nocturnal Penile Tumescence Testing
Nocturnal penile tumescence testing was once frequently performed, as it was thought to be useful in distinguishing psychogenic from organic impotence. This test involves placing several bands, using a device such as the Rigiscan monitor, around the penis and instructing the patient to wear it for 2-3 successive nights. If an erection occurs, which is expected during rapid eye movement sleep, the force and duration are measured on a graph. Inadequate or absent nocturnal erections suggest organic dysfunction, while a normal result indicates a high likelihood of a psychogenic etiology (see the image below).
This penile tumescence monitor is placed at the base and near the corona of the penis. It is connected to a monitor that records a continuous graph depicting the force and duration of erections that occur during sleep. The monitor is strapped to the leg. The nocturnal penile tumescence test is conducted on several nights to obtain an accurate indication of erections that normally occur during the alpha phase of sleep. Other devices are available to provide similar information. Some are also able to measure rigidity (resistance to mild compression) and tumescence (size). This test is rarely used in current practice, but it can be helpful in situations in which the diagnosis is in doubt.
Neurological Testing
Formal neurological testing is not needed in the vast majority of patients with ED. Those with a history of central nervous system (CNS) problems, peripheral neuropathy, diabetes, or penile sensory deficit may benefit from some level of neurological testing.
Latini DM, Penson DF, Lubeck DP, Wallace KL, Henning JM, Lue TF. Longitudinal differences in disease specific quality of life in men with erectile dysfunction: results from the Exploratory Comprehensive Evaluation of Erectile Dysfunction study. J Urol. Apr 2003;169(4):1437-42. [Medline].
Andersson KE, Wagner G. Physiology of penile erection. Physiol Rev. Jan 1995;75(1):191-236. [Medline].
Anatomy of the Lower Urinary Tract and Male Genitalia. Campbell-Walsh Urology 9th edition. Philadelphia: WB Saunders..
Yucel S, Baskin LS. Identification of communicating branches among the dorsal, perineal and cavernous nerves of the penis. J Urol. Jul 2003;170(1):153-8. [Medline].
Costabile RA. Optimizing treatment for diabetes mellitus induced erectile dysfunction. J Urol. Aug 2003;170(2 Pt 2):S35-8; discussion S39. [Medline].
De Berardis G, Pellegrini F, Franciosi M, Belfiglio M, Di Nardo B, Greenfield S, et al. Identifying patients with type 2 diabetes with a higher likelihood of erectile dysfunction: the role of the interaction between clinical and psychological factors. J Urol. Apr 2003;169(4):1422-8. [Medline].
Romeo JH, Seftel AD, Madhun ZT, Aron DC. Sexual function in men with diabetes type 2: association with glycemic control. J Urol. Mar 2000;163(3):788-91. [Medline].
Burchardt M, Burchardt T, Baer L, Kiss AJ, Pawar RV, Shabsigh A, et al. Hypertension is associated with severe erectile dysfunction. J Urol. Oct 2000;164(4):1188-91. [Medline].
Larson TR. Current treatment options for benign prostatic hyperplasia and their impact on sexual function. Urology. Apr 2003;61(4):692-8. [Medline].
Araujo AB, Durante R, Feldman HA, Goldstein I, McKinlay JB. The relationship between depressive symptoms and male erectile dysfunction: cross-sectional results from the Massachusetts Male Aging Study. Psychosom Med. Jul-Aug 1998;60(4):458-65. [Medline].
Goldstein I. The mutually reinforcing triad of depressive symptoms, cardiovascular disease, and erectile dysfunction. Am J Cardiol. Jul 20 2000;86(2A):41F-45F. [Medline].
Kawanishi Y, Lee KS, Kimura K, Koizumi T, Nakatsuji H, Kojima K, et al. Screening of ischemic heart disease with cavernous artery blood flow in erectile dysfunctional patients. Int J Impot Res. Apr 2001;13(2):100-3. [Medline].
Kloner RA, Mullin SH, Shook T, Matthews R, Mayeda G, Burstein S, et al. Erectile dysfunction in the cardiac patient: how common and should we treat?. J Urol. Aug 2003;170(2 Pt 2):S46-50; discussion S50. [Medline].
Valicenti RK, Bissonette EA, Chen C, Theodorescu D. Longitudinal comparison of sexual function after 3-dimensional conformal radiation therapy or prostate brachytherapy. J Urol. Dec 2002;168(6):2499-504; discussion 2504. [Medline].
Marceau L, Kleinman K, Goldstein I, McKinlay J. Does bicycling contribute to the risk of erectile dysfunction? Results from the Massachusetts Male Aging Study (MMAS). Int J Impot Res. Oct 2001;13(5):298-302. [Medline].
Goldstein I, Lurie AL, Lubisich JP. Bicycle riding, perineal trauma, and erectile dysfunction: data and solutions. Curr Urol Rep. Nov 2007;8(6):491-7. [Medline].
Feldman HA, Goldstein I, Hatzichristou DG, Krane RJ, McKinlay JB. Impotence and its medical and psychosocial correlates: results of the Massachusetts Male Aging Study. J Urol. Jan 1994;151(1):54-61. [Medline].
Seftel AD, Strohl KP, Loye TL, Bayard D, Kress J, Netzer NC. Erectile dysfunction and symptoms of sleep disorders. Sleep. Sep 15 2002;25(6):643-7. [Medline].
Heruti R, Shochat T, Tekes-Manova D, Ashkenazi I, Justo D. Association between erectile dysfunction and sleep disorders measured by self-assessment questionnaires in adult men. J Sex Med. Jul 2005;2(4):543-50. [Medline].
Cosgrove DJ, Gordon Z, Bernie JE, Hami S, Montoya D, Stein MB, et al. Sexual dysfunction in combat veterans with post-traumatic stress disorder. Urology. Nov 2002;60(5):881-4. [Medline].
Rosen RC, Cappelleri JC, Smith MD, Lipsky J, Peña BM. Development and evaluation of an abridged, 5-item version of the International Index of Erectile Function (IIEF-5) as a diagnostic tool for erectile dysfunction. Int J Impot Res. Dec 1999;11(6):319-26. [Medline].
Rosen RC, Riley A, Wagner G, Osterloh IH, Kirkpatrick J, Mishra A. The international index of erectile function (IIEF): a multidimensional scale for assessment of erectile dysfunction. Urology. Jun 1997;49(6):822-30. [Medline].
Alemozaffar M, Regan MM, Cooperberg MR, et al. Prediction of erectile function following treatment for prostate cancer. JAMA. Sep 21 2011;306(11):1205-14. [Medline].
Brock G, Nehra A, Lipshultz LI, Karlin GS, Gleave M, Seger M, et al. Safety and efficacy of vardenafil for the treatment of men with erectile dysfunction after radical retropubic prostatectomy. J Urol. Oct 2003;170(4 Pt 1):1278-83. [Medline].
Raina R, Lakin MM, Agarwal A, Sharma R, Goyal KK, Montague DK, et al. Long-term effect of sildenafil citrate on erectile dysfunction after radical prostatectomy: 3-year follow-up. Urology. Jul 2003;62(1):110-5. [Medline].
Derby CA, Mohr BA, Goldstein I, Feldman HA, Johannes CB, McKinlay JB. Modifiable risk factors and erectile dysfunction: can lifestyle changes modify risk?. Urology. Aug 1 2000;56(2):302-6. [Medline].
Benet AE, Melman A. The epidemiology of erectile dysfunction. Urol Clin North Am. Nov 1995;22(4):699-709. [Medline].
Laumann EO, Paik A, Rosen RC. Sexual dysfunction in the United States: prevalence and predictors. JAMA. Feb 10 1999;281(6):537-44. [Medline].
Braun M, Wassmer G, Klotz T, Reifenrath B, Mathers M, Engelmann U. Epidemiology of erectile dysfunction: results of the 'Cologne Male Survey'. Int J Impot Res. Dec 2000;12(6):305-11. [Medline].
Niederberger C, Lonsdale J. Erectile dysfunction - patient characteristics and attitudes based on a large-scale male health study conducted in US, Europe, Mexico and Brazil. [abstract 594]. J Urol. 2002;167.
Araujo AB, Travison TG, Ganz P, Chiu GR, Kupelian V, Rosen RC, et al. Erectile dysfunction and mortality. J Sex Med. Sep 2009;6(9):2445-54. [Medline].
Thompson IM, Tangen CM, Goodman PJ, Probstfield JL, Moinpour CM, Coltman CA. Erectile dysfunction and subsequent cardiovascular disease. JAMA. Dec 21 2005;294(23):2996-3002. [Medline].
[Guideline] The process of care model for evaluation and treatment of erectile dysfunction. The Process of Care Consensus Panel. Int J Impot Res. Apr 1999;11(2):59-70; discussion 70-4. [Medline].
Lue TF, Giuliano F, Montorsi F, Rosen RC, Andersson KE, Althof S, et al. Summary of the recommendations on sexual dysfunctions in men. J Sex Med. Jul 2004;1(1):6-23. [Medline].
Althof SE, Seftel AD. The evaluation and management of erectile dysfunction. Psychiatr Clin North Am. Mar 1995;18(1):171-92. [Medline].
American Urological Association. Management of Erectile Dysfunction. Available at http://www.auanet.org/content/guidelines-and-quality-care/clinical-guidelines.cfm?sub=ed. Accessed February 9, 2011.
[Guideline] Rosen RC, Jackson G, Kostis JB. Erectile dysfunction and cardiac disease: recommendations of the Second Princeton Conference. Curr Urol Rep. Nov 2006;7(6):490-6. [Medline].
Gupta BP, Murad MH, Clifton MM, et al. The Effect of Lifestyle Modification and Cardiovascular Risk Factor Reduction on Erectile Dysfunction: A Systematic Review and Meta-analysis. Arch Intern Med. Sep 12 2011;[Medline].
Cheitlin MD, Hutter AM Jr, Brindis RG, Ganz P, Kaul S, Russell RO Jr, et al. ACC/AHA expert consensus document. Use of sildenafil (Viagra) in patients with cardiovascular disease. American College of Cardiology/American Heart Association. J Am Coll Cardiol. Jan 1999;33(1):273-82. [Medline].
Jackson G, Kloner RA, Costigan TM, Warner MR, Emmick JT. Update on clinical trials of tadalafil demonstrates no increased risk of cardiovascular adverse events. J Sex Med. Sep 2004;1(2):161-7. [Medline].
[Guideline] Qaseem A, Snow V, Denberg TD, Casey DE Jr, Forciea MA, Owens DK, et al. Hormonal testing and pharmacologic treatment of erectile dysfunction: a clinical practice guideline from the American College of Physicians. Ann Intern Med. Nov 3 2009;151(9):639-49. [Medline]. [Full Text].
Nehra A, Blute ML, Barrett DM, Moreland RB. Rationale for combination therapy of intraurethral prostaglandin E(1) and sildenafil in the salvage of erectile dysfunction patients desiring noninvasive therapy. Int J Impot Res. Feb 2002;14 Suppl 1:S38-42. [Medline].
Gutierrez P, Hernandez P, Mas M. Combining programmed intracavernous PGE1 injections and sildenafil on demand to salvage sildenafil nonresponders. Int J Impot Res. Jul-Aug 2005;17(4):354-8. [Medline].
Aversa A, Isidori AM, De Martino MU, Caprio M, Fabbrini E, Rocchietti-March M, et al. Androgens and penile erection: evidence for a direct relationship between free testosterone and cavernous vasodilation in men with erectile dysfunction. Clin Endocrinol (Oxf). Oct 2000;53(4):517-22. [Medline].
Aversa A, Isidori AM, Spera G, Lenzi A, Fabbri A. Androgens improve cavernous vasodilation and response to sildenafil in patients with erectile dysfunction. Clin Endocrinol (Oxf). May 2003;58(5):632-8. [Medline].
Guay AT, Bansal S, Heatley GJ. Effect of raising endogenous testosterone levels in impotent men with secondary hypogonadism: double blind placebo-controlled trial with clomiphene citrate. J Clin Endocrinol Metab. Dec 1995;80(12):3546-52. [Medline].
Jain P, Rademaker AW, McVary KT. Testosterone supplementation for erectile dysfunction: results of a meta-analysis. J Urol. Aug 2000;164(2):371-5. [Medline].
Morales A, Johnston B, Heaton JW, Clark A. Oral androgens in the treatment of hypogonadal impotent men. J Urol. Oct 1994;152(4):1115-8. [Medline].
Shabsigh R, Kaufman JM, Steidle C. Testosterone replacement therapy with testosterone-gel 1% converts sildenafil nonresponders to responders in men with hypogonadism and erectile dysfunction who failed prior sildenafil therapy. [abstract 954]. J Urol. 2003;S169S.
Hedlund H, Hedlund P. Pharmacotherapy in erectile dysfunction agents for self-injection programs and alternative application models. Scand J Urol Nephrol Suppl. 1996;179:129-38. [Medline].
Lin CS, Ho HC, Chen KC, Lin G, Nunes L, Lue TF. Intracavernosal injection of vascular endothelial growth factor induces nitric oxide synthase isoforms. BJU Int. Jun 2002;89(9):955-60. [Medline].
Linet OI, Ogrinc FG. Efficacy and safety of intracavernosal alprostadil in men with erectile dysfunction. The Alprostadil Study Group. N Engl J Med. Apr 4 1996;334(14):873-7. [Medline].
Shabsigh R, Padma-Nathan H, Gittleman M, McMurray J, Kaufman J, Goldstein I. Intracavernous alprostadil alfadex (EDEX/VIRIDAL) is effective and safe in patients with erectile dysfunction after failing sildenafil (Viagra). Urology. Apr 2000;55(4):477-80. [Medline].
The European Alprostadil Study Group. The long-term safety of alprostadil (prostaglandin-E1) in patients with erectile dysfunction. The European Alprostadil Study Group. Br J Urol. Oct 1998;82(4):538-43. [Medline].
Williams G, Abbou CC, Amar ET, Desvaux P, Flam TA, Lycklama à Nijeholt GA, et al. Efficacy and safety of transurethral alprostadil therapy in men with erectile dysfunction. MUSE Study Group. Br J Urol. Jun 1998;81(6):889-94. [Medline].
Goldstein I, Payton TR, Schechter PJ. A double-blind, placebo-controlled, efficacy and safety study of topical gel formulation of 1% alprostadil (Topiglan) for the in-office treatment of erectile dysfunction. Urology. Feb 2001;57(2):301-5. [Medline].
Lewis RW, Witherington R. External vacuum therapy for erectile dysfunction: use and results. World J Urol. 1997;15(1):78-82. [Medline].
Lewis RW. Long-term results of penile prosthetic implants. Urol Clin North Am. Nov 1995;22(4):847-56. [Medline].
Mulhall JP, Ahmed A, Branch J, Parker M. Serial assessment of efficacy and satisfaction profiles following penile prosthesis surgery. J Urol. Apr 2003;169(4):1429-33. [Medline].
Rajpurkar A, Dhabuwala CB. Comparison of satisfaction rates and erectile function in patients treated with sildenafil, intracavernous prostaglandin E1 and penile implant surgery for erectile dysfunction in urology practice. J Urol. Jul 2003;170(1):159-63. [Medline].
Montorsi F, Salonia A, Deho' F, Cestari A, Guazzoni G, Rigatti P, et al. Pharmacological management of erectile dysfunction. BJU Int. Mar 2003;91(5):446-54. [Medline].
Ernst E, Pittler MH. Yohimbine for erectile dysfunction: a systematic review and meta-analysis of randomized clinical trials. J Urol. Feb 1998;159(2):433-6. [Medline].
Rogers RS, Graziottin TM, Lin CS, Kan YW, Lue TF. Intracavernosal vascular endothelial growth factor (VEGF) injection and adeno-associated virus-mediated VEGF gene therapy prevent and reverse venogenic erectile dysfunction in rats. Int J Impot Res. Feb 2003;15(1):26-37. [Medline].
Burchardt M, Burchardt T, Anastasiadis AG, Buttyan R, de la Taille A, Shabsigh A, et al. Application of angiogenic factors for therapy of erectile dysfunction: protein and DNA transfer of VEGF 165 into the rat penis. Urology. Sep 2005;66(3):665-70. [Medline].
Liu X, Lin CS, Graziottin T, Resplande J, Lue TF. Vascular endothelial growth factor promotes proliferation and migration of cavernous smooth muscle cells. J Urol. Jul 2001;166(1):354-60. [Medline].
| Vascular causes | Atherosclerosis Peripheral vascular disease Myocardial infarction Arterial hypertension Vascular injury from radiation therapy Vascular injury from prostate cancer treatment Blood vessel and nerve trauma (eg, due to long-distance bicycle riding) Medications for treatment of vascular disease |
| Systemic diseases | Diabetes mellitus Scleroderma Renal failure Liver cirrhosis Idiopathic hemochromatosis Cancer and cancer treatment Dyslipidemia Hypertension |
| Neurologic causes | Epilepsy Stroke Multiple sclerosis Guillain-Barré syndrome Alzheimer disease Trauma |
| Respiratory disease | Chronic obstructive pulmonary disease Sleep apnea |
| Endocrine conditions | Hyperthyroidism Hypothyroidism Hypogonadism Diabetes |
| Penile conditions | Peyronie disease Epispadias Priapism |
| Psychiatric conditions | Depression Widower syndrome Performance anxiety Posttraumatic stress disorder |
| Nutritional states | Malnutrition Zinc deficiency |
| Hematologic diseases | Sickle cell anemia Leukemias |
| Surgical procedures | Brain and spinal cord procedures Retroperitoneal or pelvic lymph node dissection Aortoiliac or aortofemoral bypass Abdominal perineal resection Proctocolectomy Transurethral resection of the prostate Radical prostatectomy Cryosurgery of the prostate Cystectomy |
| Medications | Antihypertensives Antidepressants Antipsychotics Antiulcer agents (eg, cimetidine) 5-Alpha reductase inhibitors (eg, finasteride, dutasteride) Cholesterol-lowering agents |
| Treatment | Advantages | Disadvantages |
| Semirigid or malleable rod implants | Simple surgery Relatively few complications No moving parts Least expensive implant Success rate of 70-80% Highly effective | Constant erection at all times May be difficult to conceal Does not increase width of penis Risk of infection Permanently alters or may injure erection bodies Most likely implant to cause pain or erode through skin If unsuccessful, interferes with other treatments |
| Fully inflatable implants | Mimics natural process of rigidity-flaccidity Patient controls state of erection Natural appearance No concealment problems Increases width of penis when activated Success rate of 70-80% Highly effective | Relatively high rate of mechanical failure Risk of infection Most expensive implant Permanently alters or may injure erection bodies If unsuccessful, interferes with other treatments |
| Self-contained inflatable unitary implants | Mimics natural process of rigidity-flaccidity Patient controls state of erection Natural appearance No concealment problems Simpler surgery than fully inflatable prosthesis Success rate of 70-80% Highly effective | Sometimes difficult to activate the inflatable device Does not increase width of penis Mechanical breakdowns possible Long-term results not available Risk of infection Relatively expensive Permanently alters or may injure erection bodies If unsuccessful, interferes with other treatments |
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