Friday, July 18, 2008

Thigh Swelling and Veils

Radiologists have an unparalleled ability to look inside the human body, using our myriad machines. Starting with X-rays in the early part of the 20th century, radiologists eventually integrated ultrasound, CT, and MRI into their imaging armamentarium. These technologies, and others, give physicians the ability to noninvasively display the inner topography of our bodies.

In many cases, however, pictures alone do not give the answer. There is a veil over our understanding, and we cannot always make the correct diagnosis. The phrase "lifting the veil" seems to fit here; once the veil is lifted, the answer is often apparent. The phrase has been associated with wedding rituals from the dawn of civilization. In ancient Judaism, the veil was lifted prior to the consummation of the marriage. Modern brides often still wear a veil:

What, then, lifts the veil for the radiologist? Often, it is the clinical history that delivers the correct diagnosis. We live in the dark ages of medical informatics— in fifty years we will look back and marvel at all the errors that are made in medicine today simply due to a lack of accurate clinical history about the patient.

Radiologists usually read their examinations in an informational vacuum. I am fortunate enough to work with great MRI technologists, who ask the patient the right questions, and usually obtain the information I need to interpret the examination properly. If the pictures do not "fit" the clinical history, then it is time for me to call the patient and/or the physician, to get the information I need to lift the veil.

Forty-five year-old woman with thigh pain and swelling:


Coronal STIR image (above) reveals a fluid collection (red arrow) in the mid right thigh, with extensive soft tissue edema.


(A) Axial T1 and (B) Axial T2 fatsat images show that the fluid collection is associated with the vastus intermedius muscle, and confirm the extensive surrounding soft tissue edema.

The patient was given intravenous gadolinium, and additional imaging was performed:


Axial postcontrast T1 fatsat image depicts rim enhancement of the fluid collection, with some associated enhancement of the adjacent muscle.

The images are there, but the veil is in place— the prescription states "MRI thigh, pain and swelling".
Why would a 45 year old woman develop an angry-looking fluid collection in her thigh? The additional clinical history obtained by the technologist tells us that there is no history of blunt trauma or athletic injury, and that the symptoms have come on over the last two weeks. The mystery remains.

So.... it's time to get more information. I call the patient, and after a few questions, the mists part. She suffers from multiple sclerosis, and injects herself in the thigh with the immunomodulator Avonex. This additional information tells us that this is a case of pyomyositits. The fluid collection is an abscess within the vastus intermedius muscle, and it will have to be drained, and the patient put on antibiotics.

This is not a difficult case, but it illustrates what Professor William Osler taught us over 100 years ago— the importance of accurate information about the patient. Fundamental truths rarely change.


1 comment:

painful said...

I am a 49 year old female that has had a swollen thigh with extreme pain for 4 months. I have been to PT with no great results. I explained that my left thigh is swollen, with a fluid like blue colored area on the left side. Not one orthopedic doc I have seen has bothered to look they all took 1 xray and want to replace my hip because I have too insurance. Even the PT therapist agrees more tests are needed. Now today I called and explained that this weekend it's red and blue and swelled to twice it's size kind of like a bee sting hot and red. I have not been able to walk for 2 days, packed in ice I am in pain an scared. I called my doc again and this time my husband told them this is not normal I am an active person with a high pain tolerance, very high, never usually a complainer. At this point I would like to cut my leg open and find out what is hurting me. I feel like I am carrying a sac of fluid that swishes around as I walk. Hopefully they will find out what is wrong soon.