E1844. Adaptation from Scarcity: Review of Noncontrast Computed Tomography Findings in Times of Iodinated Contrast Media Shortage
  1. Jacob Musiol; Brooke Army Medical Center
  2. Jason Kim; Brooke Army Medical Center
  3. Matthew Kluckman; Brooke Army Medical Center
  4. Francis Cloran; Brooke Army Medical Center
Iodinated contrast media is an indispensable tool within the field of radiology and recent shortages have given new value to the noncontrast computed tomography (CT) examination for screening of pathologies typically diagnosed on contrast enhanced CT. Vascular disorders, neoplasms and traumatic solid organ injuries are such groups of pathology with subtle findings that may be easily overlooked. In the setting of abdominal trauma specifically, the addition of contrast media increases sensitivity for abdominal solid organ injury from 62% to 92%. Understanding of these noncontrast findings is crucial in the setting of contrast media shortage and, incidentally, on noncontrast examinations ordered for an alternate indication.

Educational Goals / Teaching Points
The purpose of this exhibit is to review the imaging findings seen in disease processes which are typically diagnosed by contrast enhanced CT. Through understanding of these findings, the interpreting radiologist may better advise the ordering provider on which patients truly require contrast for definitive diagnosis of life-threatening conditions. Disease entities to be discussed include portal vein thrombosis, pulmonary embolism, dural venous sinus thrombosis, abdominal neoplasm, solid and hollow abdominal organ injury as well as blunt traumatic aortic injury. Typical noncontrast findings will be demonstrated with brief discussion of traditional methods for diagnosis of the discussed entities.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
A ubiquitous finding of venous thrombosis is hyperattenuation of the vessel lumen, often accompanied by enlargement of vessel caliber due to expansile thrombus. Sequelae of venous occlusion may be seen, to include venous collateralization and ischemia. Diagnosis of traumatic solid organ injury primarily relies on identification of free fluid, intramural gas and parenchymal abnormalities in the setting of known trauma. A high index of suspicion for injury should be assumed with any abnormality in the setting of trauma. Pulmonary embolism is often occult however sequelae of the embolism may be visible as a wedge-shaped consolidation representing pulmonary infarction. Neoplasm identification relies on identification of subtle differences in abdominal organ attenuation which often require utilization of uniquely tailored window and level settings for optimal detection.

Several pathologic entities that typically rely on iodinated contrast media for CT diagnosis demonstrate subtle, but characteristic findings on noncontrast CT examination. Identification of these findings by the interpreting radiologist is invaluable for diagnosis of life-threatening disease, which may otherwise evade detection.