The Right Exam for the Right Diagnosis

The Department of Radiology at Cincinnati Children’s provides many modalities or imaging services that evaluate pediatric diseases or trauma. The services we offer are MRI, CT, ultrasound, nuclear medicine, radiography (x-ray), fluoroscopy and interventional radiology (IR). These modalities are specialized in the type of imaging that helps our radiologists diagnosis our patients’ particular ailments.

We offered one of our radiologists three examples of patients with certain ailments or traumas and asked which imaging modality they would choose to help them provide a proper diagnosis. We also asked why that particular exam modality was chosen instead of another.

1. If a patient comes in with a head trauma, which modality(s) would we use to diagnose the patient? Also, which modality would we not use and why?
   1. Based on the clinical exam, we would typically get a non-contrast head CT. You would not use contrast for trauma. Contrast is typically used for other reasons such as emphasizing blood vessels.

1. A patient comes in with no bowel movement and abdominal pains. Which modality(s) would we use and not use?
   1. Typically, an abdominal x-ray and/or an ultrasound. A CT or MRI exam would be needed if the plain film (x-ray) or ultrasound warranted further workup.
   2. A fluoroscopy exam such as an upper GI or contrast enema may be needed if there is a concern for abnormal twisting of the bowel.

1. A patient comes in with a soccer game knee injury. Which modality(s) would we use and not use?
   1. We usually start with an x-ray. If there is clinical concern for ligament damage, an MRI may be ordered. CT may be needed if there is a complex fracture.
   2. An ultrasound is not a chosen exam for this type of injury because it cannot evaluate for fractures.

Bonus Question:

1. With the type of ailment and/or trauma mentioned in the questions above, would a nuclear medicine exam be appropriate?
   1. Nuclear medicine exams are mainly used in diagnosing and treating certain illnesses such as thyroid diseases, cancer workup and follow-ups. Radioactive materials called radiopharmaceuticals are used in these procedures. Other exam studies that use nuclear medicine include lung perfusion scans (probably more in adults), bladder scans to diagnosis vesicoureteral reflux, and gastric emptying studies.

Contributions by Dr. Manish Patel, Glenn Miñano, BFA; editor; Meredith Towbin, copy editor