Medical School 2020, Year 4, Week 29 (Radiology, week 1)

A two-week elective in MSK (musculoskeletal) radiology. The private practice radiology group that staffs our health system’s department offers 4 hours per day for medical students. I’ll be working in a large newly constructed clinic building from 9:00 – 11:00 am and 1:00 – 3:00 pm each weekday.

A typical day is as follows: I meet the attending on the MSK seat at 9:00 am. Precise Prasanna, a 39-year-old MSK fellowship-trained radiologist, is walking on the treadmill and dictating a shoulder MRI. He stops the treadmill to chat for a few minutes. Having arrived at 8:00 am, he is caught up on the worklist and has “parked” five interesting cases from this morning. He leaves the room for five minutes to refill his water and chat with his colleague on the abdominal seat while I go through them on the diagnostic monitor screen. 

I report what I have observed: “There is a high T2 signal in the right superior hip labrum.” He replies, “Good, look at the cam deformity [enlarged femoral head knocks into the acetabulum] causing femoral acetabular impingement.” He continues, “FAI is now known to be the most common cause of early osteoarthrosis. We see this all the time in female soccer players. A 10-year-old presents for anterior hip pain from a labrum tear. When you ask them they sometimes report their hip ‘stopping’ but kids get used to the impingement feeling. Twenty years ago we would have forgotten about it; now we realize FAI causes early OA so we intervene before destruction of the cartilage.” FAI can be diagnosed on a simple AP pelvis radiograph.

(Arthritis includes the suffix “itis,” suggesting inflammation, but most arthritis is due to wear and therefore osteoarthrosis is the preferred term.)

He points out the interesting aspects of 20 X-rays and 6 MRIs before it is time for live patients. We do three arthrograms, in which contrast agent is injected into the joint space under X-ray guidance. Most commonly, this is with gadolinium contrast in preparation for an MRI to fully assess the hip or shoulder labrum. Sometimes, this is to get better information from a patient who is not a candidate for an MRI. For example, Prasanna performs a shoulder arthrogram on a 28-year-old female bicycle accident victim whose implanted hardware following a previous humeral head fracture (motor vehicle collision) would distort the signal from susceptibility artifact. He points to the leaking of contrast from the joint space into the subacromial/subdeltoid bursa (fluid-filled cushion underneath tendons), indicating a full-thickness tear of the supraspinatus tendon. 

After lunch with Jane and our new puppy, I return for the 1:00 pm session. The radiologist in the abdominal seat calls me over to look at a CT scan of the chest and abdomen. “What do you see?” I respond, “There is a clear hypointensity disrupting the bright signal of the right pulmonary artery. Is this a pulmonary embolism?” He answers, “Yeah, I just sent her to the hospital. I don’t see any right heart strain. That’s all!”

Prasanna dictates reports with PowerScribe, voice recognition software specific to radiology. Every word he uses serves to further delineate the pathologic process. He explains to me that the main goal of an musculoskeletal radiologist is to pick up subtle findings of a pathologic process, e.g., rheumatoid arthritis, psoriatic arthritis or severe meniscus tears, before it severely damages the articular (hyaline) cartilage. Once destroyed the joint is unsalvageable and must be replaced (arthroplasty). “For some diseases we can stop the inflammation with drugs or for some mechanical injuries an orthopedist can operate and prevent OA. If you see acute, non-traumatic, monoarticular arthritis, treat it as a septic joint until tapped [remove fluid with a needle].”

Every hour with Prasanna is an opportunity to learn more vocabulary, e.g., the Lisfranc ligament, named after the French surgeon who pioneered the “Lisfranc amputation” of the tarsal-metatarsal joint (mid foot) during the early 1800s. I learn names for common injuries from a shoulder dislocation, including the Hill-Sachs lesion (humeral head fracture as it strikes the glenoid) and the commonly accompanying Bankart fracture of the glenoid.

[Editor: read Madame Bovary for some insight into 19th century French foot surgery.]

School administrators had stressed that I was to work only with the MSK seat and stick to the 9-11, 1-3 schedule. On Thursday, however, I asked the two radiologists if it would be okay to work from 9-1, spending half the time with the abdominal seat, and having the whole afternoon free with the puppy. “Of course,” was the answer.

I watch Prasanna perform a hip arthrogram in prep for an MRI on a 59-year-old with worsening anterior hip pain and clicking for 3 months. He weighs at least 300 lbs. Once the needle is in the joint space, straw-color fluid slowly flows out of the catheter. This went on for a few minutes, until Prasanna aspirates a total of 50mL. “That feels so much better,” exclaims the patient. “I’m glad, the pain might come back a bit as I inject the contrast now.” After the procedure, he asks, “Do I need a hip replacement?” The radiologist explains, “We’ll know more once we get the MRI, but from just this X-ray, I see preservation of the joint space so my guess is no. You do have a large joint effusion and at least a labral tear so you might still need surgery, but not a joint replacement.”

The abdominal seat is reading a pelvic MRI on a 49-year-old female for rectal cancer staging. “The most important thing is if the tumor invades the sphincter complex.” The internal and external anal sphincter muscles are highlighted by the clear “intersphincteric fat pad” that is being pushed by the tumor on the posterior lateral side. The radiologist: “This is bad. She is going to probably have to get an APR (abdominal perineal resection, in which they remove the anus and create a colostomy). We’ll see what the rectal surgeons say at tumor board next week.”

We have a CT angiogram of an 86-year-old for an adrenal mass, her fourth in two years, due to an anomaly discovered on a CT scan after a fall. The abdominal radiologist says that the test should never have been ordered. “Leave this woman alone. Adrenal masses are statistically benign in the absence of metastatic disease (e.g., lung cancer). Teleradiologists never have the guts to ignore something out of fear of getting sued so she’s subject to never-ending imaging follow up.” He continues, “It’s weird to say, but I don’t always want the ordering provider to follow every finding in my report. Don’t treat the image, treat the patient. We balance this with the knowledge that this report will be forever cemented into the patient chart for litigation years in the future. We used to call up the ordering provider, or he would come down to us. With teleradiology, the doctors don’t collaborate and each one tries to defend against any possible lawsuit. It’s almost like we are in a game of tug-of-war on who bears legal ownership of a patient. Tag, you’re it! The result is that a patient who lives 4 hours from the nearest MRI machine will be doomed to perpetual follow-up on a statistically benign tumor.”

Statistics for the week… Study: 0 hours. Sleep: 8 hours/night; Fun: 2 nights. Example fun: Jane and I attend an engagement party for Outdoors Oswald, a mountain biker applying to emergency medicine at prestigious institutions. His fiance works for Epic, which allows her to work from home most days. She hopes to end up in New York City, even though “we’ll be broke.” They rented a private downstairs room, but did not order any food for the gathering. About half of the class was invited and consequently the open bar was used to the fullest extent. We left at 1:00 am with several classmates to grab a slice of pizza before Ubering home.

The rest of the book: http://fifthchance.com/MedicalSchool2020