A penile doppler is a study that looks at blood flow the penis .To get a normal erection the man needs certain blood vessels to the penis to open up or dilate. The artery that runs through the middle of the penis which causes an erection is called the cavernosal artery. Many of the diseases that cause erectile dysfunction do so by narrowing the blood vessels leading to this artery. This prevents adequate blood flow to the artery and causes poor erections.
The penile doppler is way of evaluating the health of those blood vessels. This a procedure where a medication is injected in the penis to cause an erection. The doppler will then look at flow through that cavernosal artery which causes erections. Two main issues happen with blood vessels in the penis
1) Not enough blood is coming into the penis(arterial disease)
2) Blood isn't trapped in the penis(venous disease)
Also if you have Peyronie's Disease which is caused by a build up of scar tissue a penile doppler can be helpful. The doppler will assess the blood vessels and the ultrasound probe can often see the scar tissue. As well you can measure the curve all of which is helpful for determining treatment.
If you have erectile dysfunction or Peyronie's Disease a doppler may help development a treatment plan for you.