Why Prostate Ultrasounds Are an Important Diagnostic Tool

A prostate ultrasound is often used early as a way of diagnosing prostate cancer. Prostate cancer develops in the prostate, a small gland that makes seminal fluid and is one of the most common types of cancer in men.

Prostate cancer usually grows over time, staying within the prostate gland at first, where it may not cause serious harm. While some types of prostate cancer grow slowly and may need minimal or no treatment, other types are aggressive and can spread quickly. The earlier you catch your prostate cancer, the better your chance of successful treatment.

If your doctor suspects you might have prostate cancer they will conduct a number of tests which may include a prostate-specific antigen (PSA) test, a digital exam of your prostate, and an ultrasound. If your blood work comes back and your PSA is high, your prostate feels abnormal upon exam and the ultrasound show signs of cancer, your doctor will likely want to do a biopsy. 

Advanced prostate cancer can cause signs and symptoms including:

• Trouble urinating
• Decreased force in the stream of urine
• Blood in the semen
• Discomfort in the pelvic area
• Bone pain
• Erectile dysfunction

Ultrasound imaging uses high-frequency sound waves to create a picture of the prostate. Ultrasounds are used early in the diagnostic process to determine whether your prostate is enlarged or has an abnormal or asymmetrical shape. If your prostate is enlarged without any other characteristics of cancer, you may just have benign prostate hyperplasia. As you age, your prostate increases in size. An ultrasound can help your doctor determine if your prostate's size increase is normal and age-related or a sign of prostate cancer.

Ultrasound is also used very frequently during a prostate biopsy to guide the physician to biopsy exactly where needed. In order to produce an image of the prostate, a thin ultrasound probe is inserted a short distance into the rectum. This probe emits high-frequency sound waves and detects their return. These sound waves can then be detected and measured as they reflect off of various structures inside the body.

When sound waves echo off of an object, they change slightly. The ultrasound machine can interpret these very tiny changes in the character of the returning sound wave to make determinations about the object (such as the prostate) that it has hit. Different types of structures reflect or “echo” sound waves differently. These differences can be detected and an image produced that shows where one structure stops and another starts. This allows for a detailed view of the area near the ultrasound probe.

Measurements can be made about the size and shape of the object, how far from the probe it is, and what its makeup is. For instance, ultrasound can determine whether an object is solid, full of liquid, or a little of both. Z

As the ultrasound is being performed, the image that is produced is in real-time. This means your doctor can take a biopsy or do other procedures while an ultrasound image is being produced.