E2784. Bilateral Symmetry is Not Your Enemy: Review of Common Causes of Symmetric Brain Signal Abnormalities
  1. Rana Gordji; University of Mississippi Medical Center
  2. Johnny Yang; University of Mississippi Medical Center
  3. Shiv Patel; University of Mississippi Medical Center
  4. Logan Ryals; University of Mississippi Medical Center
  5. Charlotte Taylor; University of Mississippi Medical Center
Symmetry is an often-used tool by radiologists who have it built into their search patterns since the beginning of their training. However, whether by coincidence or design sometimes a disease presents symmetrically thereby reducing the usefulness that natural symmetry provides in isolating radiologic abnormalities. In these cases, identifying the presence of disease can be difficult.

Educational Goals / Teaching Points
Upon review of this case-based educational exhibit, the reader will be able to: recognize the common disease processes resulting in symmetric brain signal abnormalities; describe the related magnetic resonance (MR) imaging findings; and identify the etiology, clinical presentation, and outcome of the diseases.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
Cases to be reviewed are spread across a wide range of etiologies involving the brain. These cases include diffuse axonal injury, global anoxic brain injury, smoke inhalation injury, Creutzfeldt-Jacob disease, leukodystrophies, posterior reversible encephalopathy syndrome, Wernicke encephalopathy, acute disseminated encephalitis, meningoencephalitis, glial fibrillary acid protein encephalitis, hypertensive hemorrhages, cerebral amyloid angiopathy, cerebellar metastatic disease, fat emboli, chronic small vessel ischemic disease, osmotic demyelination, hypoglycemic brain injury, hypoxic ischemic injury (acute and subacute phases), familial cavernous malformation, cerebral amyloid angiopathy, neurodegeneration with brain iron accumulation, and pantothenate kinase-associated neurodegeneration. For each of these cases, the key MR imaging findings of the cases will be demonstrated and discussed.

Disease processes in the brain that present symmetrically can pose a potential problem to the unsuspecting radiologist. With familiarity of common symmetrically presenting neurologic diseases these critical findings are less likely to be missed allowing the patient to receive appropriate and timely care.