E4801. Spectrum of Intracranial Pathology With Diffusion Abnormalities: A Case-Based Review
  1. Alexander Chavez-Yenter; MedStar Georgetown University Hospital
  2. Earn Chun Christabel Lee; MedStar Georgetown University Hospital
  3. Erini Makariou; MedStar Georgetown University Hospital
DWI reveals information about the movement of water molecules in tissues, aiding in detection and characterization of pathology. Major causes of abnormalities detectable on DWI include ischemia, hypercellularity, and increased viscosity. Beyond identification of ischemic stroke, DWI plays an important role in characterizing and grading tumors, infectious and inflammatory processes, and identification of benign mimickers of disease. This educational exhibit will review the mechanisms that lead to diffusion abnormalities and cover the spectrum of pathology observable on DWI through a series of cases. Examples of cases would include infarct, glioblastoma, lymphoma, medulloblastoma, meningioma, choroid xanthogranuloma, abscess, subdural empyema, epidermoid cyst, cholesteatoma, and cytotoxic lesion of the corpus callosum.

Educational Goals / Teaching Points
Goals of the exhibit include familiarizing participants with the basic principles of DWI, understanding the mechanisms that cause diffusion abnormalities, and reviewing the spectrum of pathology in which DWI plays an important clinical role.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
Abnormalities presented in this case series are that of “restricted diffusion”, observed on DWI as hyperintense signal with corresponding hypointense ADC signal. This combination reflects a relative reduction in the ability of water molecules to diffuse inside of and/or between the intracellular and extracellular compartments.

Observable abnormalities on DWI are often of important clinical relevance. Understanding of the basic mechanisms that cause diffusion abnormalities aids in characterization of pathology. Through this case-based review, participants should be familiar with the range of pathology detectable by DWI abnormalities.