2004 Radiology Exam - Thorax Case 2

Objective of the Case
To evaluate the candidate’s ability to use radiographic findings to build a logical ranked diffential list.

Information Provided to Candidate
1. Signalment: 10 yr FS Dalmatian
2. History: 3 day history of ‘dry heaving’ and 2 episodes of collapse
3. Lateral and dorsoventral radiographs of the thorax are available.
4. State the radiographic findings.
5. What is your assessment of these findings?
6. Are further imaging studies needed? If so, what are they and why? If no, why not?

See images below. Click to enlarge.

Findings Expected from Candidate
There is cardiomegaly present as well as an alveolar infiltrate in the right middle and right caudal lung lobes. Pleural fissure lines can be seen indicative of a small amount of pleural effusion. Because of the infiltrate, it is difficult to assess the pulmonary vasculature, but the pulmonary veins in the cranial lungs are larger than the pulmonary arteries (particularly seen on the DV view).

Conclusion Expected from the Candidate
The candidate’s were expected to conclude that the infiltrate in the lungs was most likely due to congestive heart failure given the cardiac and pulmonary vein changes. No points were deducted if pneumonia in addition to congestive failure was considered. Differentials for the cardiomegaly should have included at least dilated cardiomyopathy and/or chronic valvular disease. Additional imaging procedures that should be performed included an echocardiogram.

Summary of Overall Candidate Performance
Many of the candidates failed to recognize the pulmonary venous distension. The relied on the caudal vasculature for their evaluation, however in this case, the cranial vessels were more easily identified. Because they did not recognize the venous distension, many candidates failed to recognize this as a case of congestive heart failure. Ultimately, this animal was found to have dilated cardiomyopathy based upon echocardiography.