Penile Doppler ultrasound

Doppler penile test has no contraindications.

Your healthcare practitioner will order this test if you have symptoms related to ED such as:

• Recurring inability to get an erection 
• Complete inability to have an erection 
• Recurring inability to maintain an erection for satisfactory sexual activity

The doctor may also order this test to check your response to vasodilator drugs that are used for the treatment of ED.

Doppler penile may be done to diagnose Peyronie’s disease which presents with symptoms such as:

• Lumps in the penis
• Painful erections
• Curved penis
• Soft erections 
• Trouble with sexual intercourse

Additionally, this test helps check for priapism. The symptoms of ischaemic priapism are:

• Erection for more than four hours without sexual interest or stimulation 
• Progressive pain in penis
• Rigid penis with a soft tip

Non-ischaemic priapism is generally not as painful as ischaemic priapism but shows symptoms such as:

• Erection for more than four hours without sexual interest or stimulation
• Erect but not a fully rigid penis

Your doctor may advise you to skip medicines for ED (if you are taking any) one day prior to or on the day of the test.

Avoid nicotine products, such as cigarettes or chewing tobacco, for at least 30 minutes to two hours before the test. This is because nicotine can narrow blood vessels, which may lead to false results.

The following procedure is performed for this test:

• Your healthcare practitioner will explain the steps of the procedure to you before the test. 
• He/she will ask you to undress from the waist down and lie down on the examination table. 
• Next, the doctor will inject a vasodilator drug into the side of your penis using a tiny needle. This will increase the blood flow to your penis and help develop an erection. 
• He/she will then apply a gel on the ultrasound probe and place it on your penis. 
• As the doctor moves the probe, you may hear some swishing sounds from the ultrasound machine. The sounds indicate blood flow inside your penis.

The scanning procedure is painless. However, people who have nerve problems may feel severe aching pain for several hours after the drug is injected. There can also be a feeling of light-headedness after the injection, which usually subsides after some time.

If you experience any other discomfort, make sure to inform your doctor at the earliest.

Healthcare practitioners diagnose ED with the help of the following parameters:

• Peak systolic velocity (PSV) of the cavernosal artery (CA): Abnormal results on PSV indicate that ED is caused by insufficient blood flow from arteries (blood vessels carrying blood from the heart to the organ), also called arterial insufficiency.
• • Normal: >35 centimetre/second (cm/sec)
  • Grey zone: 25-35 cm/sec
  • Abnormal: <25 cm/sec
• Resistive index (RI) of the CA: RI can detect a venous leak even in the presence of arterial insufficiency.
  • Normal: >0.9
  • Venous leak: <0.75
• Arterial compliance of the CA:
  • 60%-75% increase in diameter
• End diastolic velocity (EDV) of the CA: EDV can indicate a venous leak, which can occur due to an impaired veno-occlusive mechanism. Veno-occlusion causes the veins to constrict and entrap blood inside the penis during an erection. A venous leak occurs when the veins do not constrict and the blood flows backwards from the penis to the body, causing ED. However, the results of EDV can be incorrect if a person has arterial insufficiency.
  • Normal: <3-5 cm/sec
  • Venous leak: >5 cm/sec
• Deep dorsal vein: It is an additional parameter to detect venous leak
  • Normal: <3 cm/sec
  • Moderate increase: 10-20 cm/sec
  • Marked increase: >20 cm/sec

The healthcare practitioner can also determine if you have inflow or outflow ED from the images obtained during the penile Doppler test.

The other conditions that can also be detected by Doppler penile are:

• Priapism 
• Peyronie’s disease
• Penile masses
• Penile trauma 
• Penile fibrosis

The most important benefit of this test is that it is non-invasive.

There is a slight risk of having a persistent erection (priapism) for several hours after the test. Inform your doctor if the erection persists for more than three hours after injecting the drug.

You can leave immediately after the test. Do not masturbate or have sexual intercourse for the rest of the day.

The other tests may depend on the conditions detected. For example, the following tests may be done with penile Doppler for ED:

• Nocturnal penile tumescence test
• Neurologic exam

Disclaimer: All results must be clinically correlated with the patient’s complaints to make a complete and accurate diagnosis. The above information is provided from a purely educational point of view and is in no way a substitute for medical advice by a qualified doctor.