Everything you need to know about penile Doppler ultrasound: What is it? How is it conducted? And can it assist in the diagnosis of erectile dysfunction?
A Doppler ultrasound (US) is an imaging test that uses high-frequency sound waves humans cannot hear. This diagnostic test is designed to assess the quality of blood flow and to measure in real time the rate of blood moving through the arteries and veins in the body, including those in the penis.
Doppler US can detect abnormal blood flow within a blood vessel, which can help diagnose and treat a variety of health conditions, including blood clots, narrowing or blockage of a blood vessel, poor circulation to a certain organ, and so forth. This procedure requires minimal preparation and is noninvasive, painless, and without side effects.
What is a Penile Doppler US test?
A penile Doppler US is an important diagnostic tool that helps assess the quality of penile blood flow (inflow) – to achieve an erection and the flow of blood out of the organ (outflow) – which brings the penis back to its flaccid state. The test likewise helps evaluate the function of penile tissues, structures, and surrounding nerves and diagnoses various conditions affecting the penis, including erectile dysfunction (ED), Peyronie’s disease (characterized by penile curvature), lumps, and more. The test can help identify what causes ED, evaluate the success rate of the various treatment options, and benefit the decision-making process regarding choosing the most appropriate treatment.
Penile Doppler US in the Diagnosis of Erectile Dysfunction
ED is a common problem for men of all ages. Under normal circumstances, penile arteries relax during sexual activity, leading to penile blood flow increase, which results in an erection. At the same time, there is a mechanism for sustaining the erection by trapping the blood in the penis by compressing the penile veins and blocking blood drainage through them. After ejaculation, this mechanism allows penile veins to return to their normal state, the blood flows out of the penis, and the organ becomes flaccid again.
When ED occurs, penile Doppler US can help identify what causes problems in achieving or maintaining an erection and can likewise predict whether the patient will respond well to the suggested medical treatment.
Usually, when there are problems in getting a full or partial erection, one of the most common assumptions is that penile arteries fail to dilate properly to allow enough blood to flow into the penis or a faulty mechanism for trapping the blood in the penis causes ‘venous leakage’ (i.e., an outflow of blood from the penis during erection).
Some medical conditions, such as arteriosclerosis (hardening of the arteries), diabetes, high blood pressure, and others, can affect the blood vessel’s ability to relax and expand to enable an increase in blood flow into the penis. One of the causes of a faulty mechanism for trapping the blood within the penis is the degradation of collagen fibers in the Tunica Albuginea – the tissue enveloping the penis. In both cases, the erection will be weak and short lasting.
Penile Doppler US can help assess whether the ED results from a blood vessels disorder (vasculogenic ED) arising out of a reduction in blood flow to the penis (inflow ED) or as a result of venous leakage during erection (outflow ED) or both. In case of inflow ED, PDE5 inhibitors drugs (such as Viagra and Sialis) or penile injections may be able to dilate the arteries enough to allow adequate erections, but this is not always the case. The test can predict whether drug treatment or penile injections will be effective and therefore save unnecessary therapies. In case of outflow ED, PDE5 inhibitors may increase the blood flow enough to achieve an erection hard and long enough for satisfactory intercourse. However, in cases of severe venous leakage (as assessed by the test), these drugs might prove ineffective, and other ED treatments will be required, such as a penile ED ring, penile vacuum device, or penile prosthetics.
Other circumstances in which penile Doppler US may be necessary include complications post pelvic surgery (usually carried out due to malignancies) due to blood vessel injury, nerve injury, or a combination of both [1]. The test can likewise detect sub-clinical (silent) heart disease) among men with ED [2, 3].
How Does Penile Doppler US Work?
A penile Doppler US test examines in real time the rate, the amount, and the direction of blood flow in penile blood vessels. A radiology technician scans the penis using an ultrasound transducer that sends ultrasound waves into the genitals and collects their echoes. The computer processes the echoes to create an image of the inside of the scanned organ while mapping blood flow in the arteries and veins. When the sound waves bounce off the blood vessels, the pitch changes in the echoes of moving blood. Therefore, if the Doppler US echoes do not change pitch, it reflects a lack of blood flow in a certain area.
What to Expect During a Penile Doppler US?
The test is performed when the penis is in the erect state, as this is the only way in which the quality of penile blood flow can be measured in real-time, and small penile structures can be observed in detail. To induce an erection, a fine needle is used to inject a vasodilator substance into the penis to increase penile blood flow. When the penis is erect, the radiology technician presses the ultrasound transducer wand along the side of the penis to perform a dynamic evaluation of blood flow velocity in and out of the organ, observe penile anatomical structures, and assess whether a problem exists in the penile blood vessels.
The patient will be instructed not to take ED medications (Viagra, Sialis, or Levitra) 24-48 hours before the rest. On the day of the penile Doppler US, the recommendation is to avoid sexual intercourse or masturbation.
The Company hereby clarifies that the information contained on the website is for informational purposes only, and is not intended to be a substitute for professional medical and healthcare advice, and does not constitute medical advice or opinion. Always seek the advice of your physician or other qualified health provider with any medical condition or question you may have regarding a medical condition.
