CIP Case of the Month

Coalescent Mastoiditis. Submitted by Harold R. Levine, MD, Kelli Y. Ha, MD, Michael J. Opatowsky, MD, MBA, and Brian O'Rourke, in point

In September 2012, ACR selected "Coalescent Mastoiditis" as the best Case in Point (CIP) submission of the month. CIP is ACR's most popular e-learning activity, offering members the opportunity to earn free CME credit for the completion of each daily case.

The post-case evaluation allows users to share their thoughts about each submission, and "Coalescent Mastoiditis" was deemed a "very useful case" on "an important and not uncommon disease process."

Harold R. Levine, MD, lead author and radiology resident at Baylor University Medical Center in Dallas, Texas, spoke with the ACR Bulletin about the case.

Q: Why did you select "Coalescent Mastoiditis" for submission to CIP?

A: Despite vast pathology at our large tertiary care center, it is still fairly uncommon to encounter a classic case in which almost every described complication of the disease process is exhibited. This is an excellent example of multimodality evaluation of a known pathology in a case that exhibits virtually all of its uncommonly seen, dire complications. Without being completely familiar with the potential complications of a specific disease process, a radiologist may misinterpret an examination with potentially disastrous results. An extreme case such as this one can provide an indelible reminder of the numerous and severe complications of coalescent mastoiditis.

Q: What do you want users to learn from your case?

A: Much of radiology relates to disease-pattern recognition and an understanding of basic underlying pathophysiology. Our case demonstrates important extracranial and intracranial findings seen using different imaging modalities. I want readers to be reminded of the potential consequences of coalescent mastoiditis while reinforcing their own skills effectively detecting such pathological processes.

Q: Was this a diagnostic dilemma or was it a straightforward case?

A: Our differential diagnoses were relatively concise. The patient's history and recent CT findings suggested an acute infectious or inflammatory process. One aspect that we were not able to fully pursue, given the limitations on providing intravascular contrast due to the patient's renal insufficiency, was evaluating whether the parenchymal lesions were abscesses or venous infarctions. At surgery, they proved to be purulent cavities, although on the MRI they easily might have been either abscesses or infarctions.

Q: How does this case differ from acute mastoiditis with associated complications?

A: The diversity of disease complications in a single case example sets this apart from other cases of mastoiditis. Although you occasionally encounter one of these complications, this case demonstrates almost all of the known complications in one example. This case can remind us of the need to be thorough and diligent when we see or suspect any case of acute mastoiditis.

Q: Did you learn anything new about the case while preparing it for submission to CIP?

A: Preparing this case gave me the opportunity to learn more about the intricate anatomy of the temporal bone. I learned that a high relative proportion of patients who develop epidural abscesses also develop dural venous thrombosis. This often poses a therapeutic dilemma, as treatment with anticoagulation can increase risk for intracranial hemorhages. I gained a permanent appreciation of this disease process and learned how to evaluate for potentially subtle but critical radiological findings.

Q: Why should residents take advantage of CIP?

A: CIP is a wonderful resource that I have used to supplement didactic lectures, reading-room learning, and my personal reading program. It is very convenient. Residents can learn something from every case. CIP can be read on personal electronic devices in the reading room, which allows me to ask my staff radiologists for further clarification of key concepts. CIP is also an outstanding medium that can form the backbone of a case review lecture session.

"Coalescent Mastoiditis" was published on Septebmer 6, 2012. To view the full case, visit

By Anastasia Simkanin
Anatasia Simkanin (This email address is being protected from spambots. You need JavaScript enabled to view it.) is the CIP manager for the ACR Education Department

Share this content

Submit to FacebookSubmit to Google PlusSubmit to TwitterSubmit to LinkedIn