title: Clinically presenting acute/subacute ischemic stroke: differential diagnosis of the non-enhanced CT hypodensity by advanced neuroimaging.
abstract: OBJECTIVE
  Patients presenting to the emergency room with an acute or subacute onset of focal neurological deficits are evaluated initially by non-contrast computed tomogram (CT) of the brain. This is primarily carried out to differentiate an ischemic from hemorrhagic stroke. However, other neurological conditions may have a similar clinical presentation as well as only hypodensities on CT scan, thus mimicking ischemic stroke. This review focuses on the advanced neuroimaging modalities that help differentiate these other conditions from a cerebral infarction.
  
  
  METHODS
  The literature was reviewed in order to ascertain what conditions would clinically and by CT mimic an acute/subacute ischemic infarction, and what advanced neuroimaging techniques would be most useful in differentiating these conditions.
  
  
  RESULTS
  Several infectious, inflammatory, metabolic and vascular diseases were found with clinical presentations identical to subacute/acute ischemic cerebral infarction, which also could demonstrate only hypodensities on a non-enhanced CT scan. However, advanced neuroimaging techniques could readily differentiate these conditions from ischemic infarction.
  
  
  CONCLUSIONS
  As presented in this review, although several diseases initially present a diagnostic dilemma upon presentation because of their clinical and non-enhanced CT similarities to cerebral infarction, advanced diagnostic neuroimaging readily establishes their unique pathologies.
authors.affiliation: Department of Neurology, Louisiana State University School of Medicine in Shreveport, Shreveport, LA 71130, USA.
authors.forename: Vivek
authors.initials: V
authors.lastname: Misra
authors.forename: Halim
authors.initials: H
authors.lastname: Fadil
authors.forename: Romy
authors.initials: R
authors.lastname: Hoque
authors.forename: Uma
authors.initials: U
authors.lastname: Menon
authors.forename: Eduardo
authors.initials: E
authors.lastname: Gonzalez-Toledo
authors.forename: Stephen
authors.initials: S
authors.lastname: Jaffe
mesh_terms: D001921:Brain / Q000098:blood supply / Q000378:metabolism / Q000473:pathology; D002545:Brain Ischemia / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology*; D002494:Central Nervous System Infections / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000473:pathology; D002561:Cerebrovascular Disorders / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000473:pathology; D003711:Demyelinating Diseases / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000473:pathology; D003937:Diagnosis, Differential; D038524:Diffusion Magnetic Resonance Imaging; D006801:Humans; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D020521:Stroke / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology*; D014057:Tomography, X-Ray Computed