Doppler sonography of the penis (synonym: Doppler sonography of the penile arteries) is a noninvasive (nonsurgical) diagnostic procedure in urology and andrology (men’s medicine) that can be used, among other things, to identify the cause of erectile dysfunction (ED; erectile dysfunction). The main pathophysiological component of erectile dysfunction, which is the man’s impairment to get a sexually controlled erection, is the insufficient arterial circulation of blood in the penis. Doppler sonography can be used to accurately assess the arterial blood supply. To clarify erectile dysfunction, native color-coded Doppler sonography (FKDS) is usually first used as part of SKIT (erectile tissue injection therapy), followed by injection of prostaglandin E1, which dilates blood vessels, into the corpus cavernosum (erectile tissue) of the penis. Subsequently, perfusion (blood flow) is determined again.
Indications (areas of application)
- Exclusion of erectile dysfunction – Color-coded Doppler sonography represents the gold standard in imaging for assessing blood supply to the penis. The procedure, along with the application of a vasodilator (vasodilator), provides excellent imaging of perfusion.
- Checking the vessels of the penis in the presence of vasculitis – In the context of an inflammatory systemic vascular disease, the vessels of the penis may also be affected, so checking the perfusion by Doppler sonography may be useful.
- Malignant (malignant) change of the penis – In penile carcinoma, perfusion may be affected. Color-coded Doppler sonography is used as the method of choice for evaluation. As the tumor increases in size, infiltration of the deeper tissue structures can be demonstrated, leading to a reduction in perfusion, among other effects.
Contraindications
There are no contraindications to the performance of native Doppler sonography. However, it is possible that the application of vasodilator (vasodilating) drugs is not possible due to pre-existing conditions.
Before the examination
If erectile dysfunction is suspected, a detailed history and a wide-ranging laboratory analysis must be performed before the examination. The focus of the medical history represents the detection of erectile dysfunction due to medication, for example. In addition to beta blockers and diuretics (dehydrating drugs), psychotropic drugs and Parkinson’s medications, among others, can lead to reversible (reversible) erectile dysfunction. Erectile dysfunction can be permanently corrected by replacing the drugs with other groups of drugs (see also under “Sexual dysfunction caused by drugs”). Laboratory diagnostics should include determination of kidney function, testosterone levels (“male” sex hormone), and prolactin levels (hormone that regulates milk secretion, among other things).
The procedure
Doppler sonography is used to systematically examine the arterial blood supply to the corpus cavernosum. To better assess the function of the profunda penis artery (deep corpus cavernosum artery) supplying the corpus cavernosum (erectile tissue), a vasodilator (vasodilating) substance (usually prostaglandin E1, 5-10 µg) is usually injected into the corpus cavernosum from the lateral (side) with a thin needle (27G) (SKIT, erectile tissue injection therapy). For the examination, the erect penis lies on the patient’s abdomen after SKIT. The examination of the profunda penis artery is performed laterally on the penile shaft. If arterial flow velocities of <25 cm/s are seen in the deep cavernous arteries after stimulation (standard value for peak systolic velocity (PSV) in the penile arteries is at least 25 cm/s), an effective arterial influence disorder is present.
After the examination
The examination is followed by at least 2 hours of monitoring. Before the patient is discharged, the erectile response should have exceeded the maximum. The physician should be available for at least 12 hours. Furthermore, the patient should be given a contact person in case of priapism (permanent erection).
Possible complications
Doppler sonography is completely safe as a procedure.The use of vasoactive medications may be associated with mild complications such as hematoma (bruising) in the penile area, if appropriate.
