I’m sure many of you hear the word “ultrasound” and correlate it with pregnancy and gynecology, but ultrasound is a very safe and useful tool podiatrists have to visualize and diagnose the source of a patient’s pain. Let’s discuss some of the pros and cons of ultrasound.
First and foremost, ultrasound is very safe to the patient. Ultrasound is simply a machine that sends out sound waves at a certain frequency, which then forms an image from how the waves bounce back. Most importantly, no radiation or tissue damage occurs from these sound waves. This is supported by multiple studies and its long and continued use in visualizing babies in utero. This long history of safety has led to the development of ultrasound machines specifically made to see bone, tendon, and ligament.
Secondly, ultrasound gives a real-time image. X-rays, MRI, and CT scans are frozen images. Ultrasound gives a “living image” so that as the patient moves the foot, the image reflects that movement. This gives the doctor more information on how the foot is functioning as it moves. Without this insight, the doctor might miss the true source of the pain. Ultrasound can be used to visualize bone as well as soft tissue. In addition, when giving an injection, the doctor can give it under the guidance of ultrasound. This can help the doctor insure that the medicine is being placed in the area of inflammation.
Lastly, ultrasound is inexpensive and convenient. Ultrasound machines for foot and ankle imaging are very small and can be moved from exam room to exam room very easily. When compared to CT scans and MRI, ultrasound is much cheaper and therefore, insurances are more likely to cover the cost. Ultrasound does not require a dye to be injected into your veins (often needed for CT scans), neither does it require you to lie motionless (as is needed with MRI). All in all, is a very cost effective way to diagnose foot and ankle conditions.
The main disadvantage to ultrasound is that it requires a trained eye to both know the mechanics of the machine and to read the ultrasound image. Only after much experience can a technician consistently read an ultrasound accurately. Your podiatrist will be able to correctly interpret your ultrasound.
Now that we have covered the ways to image the foot and ankle in the office, we will discuss the more advanced imaging techniques of CT scans and MRIs in our next posts.