Do I need an MRI?

What are the role of imaging studies in the treatment of pilonidal disease?

Any time you perform an imaging study of one kind or another, it is important that the result adds to your understand what is going on, and helps guide treatment. There are various studies used to evaluate the presence and extent of pilonidal disease, including ultrasound, CT scan, and MRI.

  • Ultrasound bounces sound waves off the tissues, and by looking at what bounces back, can make a determination regarding whether there is a pocket of fluid or air under the surface.
  • A CT Scan uses X-ray beams in a circular manner, to reconstruct a 3D image of the tissues, and can show fluid, sinus tracts, swelling or inflammation.
  • A MRI can show anatomic changes, as does the CT Scan, and can also pick up inflammation.

In general, a careful history and physical examination can give a surgeon all the information they need in order to determine if a patient has pilonidal disease; imaging studies are rarely necessary. It helps if the surgeon has extensive experience with pilonidal disease and a high index of suspicion regarding its presence when there is pain or drainage in the gluteal cleft.

In our clinic, we use these imaging studies only in the unusual situation where it is unclear why a patient is having pain – particularly if it is after surgery, and there are no physical findings to explain the discomfort.

I don’t use imaging studies to determine if a patient has pilonidal disease or to define the extent, nor do I find it necessary to plan my operative approach.

So, in general, the answer is “no”, the odds are you don’t need an MRI to figure out what is going on.

What’s The Deal With Pits?

All I see is pits – do I need to worry?

Pilonidal disease occurs because of a deep gluteal cleft. Pressure develops in the cleft, and causes pores in the midline to enlarge. If one looks carefully, there can be one or several of these enlarged pores in a vertical line along the crease in patients with pilonidal disease.

Frequently, I am asked what to do about this. The answer depends on the presence of symptoms, and the personal philosophy regarding being proactive vs. waiting to see what happens.

If there are no symptoms, a reasonable strategy is to see if you can get these pores to resolve. The best way to do that is to prevent the crease from being folded as much as possible. If you are wearing any kind of stretch pants, shorts, tights, or underwear that is compressing the buttocks – wearing looser clothes may set the stage for this to reverse. You can read more about clothing choices on this page. Another way to break up the pressure gradient in the crease is to tuck a piece of gauze in the crease next to the pits. If pressure in the crease is relieved, the pits may resolve.

If there is pain, tenderness, a lump, bleeding, drainage, or a previous infection (abscess) then there is most likely a cyst under the skin, and the odds are that this will eventually cause symptoms or problems in the future. In that case, it’s reasonable to consider some sort of surgical treatment. Depending on the surgeon you see, recommendations may vary. In our clinic, we feel that if a patient is going to undergo a surgical procedure, that the cleft-lift is best, and in this situation has about a 100% success rate. Other surgeons have different strategies. This page discusses what to do with pilonidal disease with minimal symptoms, and you may find it helpful in deciding how to proceed.