title: Sulcal hyperintensity on fluid-attenuated inversion recovery imaging in acute ischemic stroke patients treated with intra-arterial thrombolysis: iodinated contrast media as its possible cause and the association with hemorrhagic transformation.
abstract: OBJECTIVE
  To investigate the effect of iodinated contrast medium on sulcal hyperintensity on fluid-attenuated inversion recovery (FLAIR) imaging immediately after intra-arterial thrombolysis in patients with acute ischemic stroke and to determine whether it may be associated with subsequent hemorrhagic transformation (HT).
  
  
  METHODS
  Fourteen consecutive patients with acute ischemic stroke who were treated with intra-arterial thrombolysis were enrolled. All patients underwent noncontrast computed tomography (NCT) and diffusion-weighted (DWI), perfusion-weighted, gradient-recalled echo (GRE), and gadolinium-enhanced T1-weighted magnetic resonance imaging (MRI). Immediate follow-up NCT and MRI (T2-weighted, FLAIR, GRE, DWI, perfusion-weighted, T1-weighted, and gadolinium-enhanced T1-weighted) were obtained and evaluated to determine the presence of sulcal hyperintensity or subarachnoid hemorrhage (SAH). The same follow-up images were obtained on days 1, 3, and 7 and evaluated to determine HT.
  
  
  RESULTS
  Sulcal hyperintensity was found in 8 (57.1%) of 14 patients and was seen as hyperattenuation on immediate follow-up NCT and as hyperintensity on T1-weighted images in 4 (50%) of 8 patients. It may be suggested that the sulcal hyperattenuation was responsible for the sulcal hyperintensity, considering signal intensity and follow-up imaging. All patients with sulcal hyperintensity showed enhancement in the corresponding gyri on gadolinium-enhanced T1-weighted imaging. Hemorrhagic transformation developed in 5 of 8 patients with sulcal hyperintensity and in 1 of 4 patients without (P = 0.031).
  
  
  CONCLUSIONS
  In acute ischemic patients treated with intra-arterial thrombolysis, sulcal hyperintensity on FLAIR imaging may be caused by iodinated contrast medium, which should not be considered SAH. Sulcal hyperintensity is significantly associated with subsequent HT.
authors.affiliation: Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Eung Yeop
authors.initials: EY
authors.lastname: Kim
authors.forename: Sam Soo
authors.initials: SS
authors.lastname: Kim
authors.forename: Dong Gyu
authors.initials: DG
authors.lastname: Na
authors.forename: Hong Gee
authors.initials: HG
authors.lastname: Roh
authors.forename: Jae Wook
authors.initials: JW
authors.lastname: Ryoo
authors.forename: Ho Kyun
authors.initials: HK
authors.lastname: Kim
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D001812:Blood-Brain Barrier / Q000187:drug effects; D002543:Cerebral Hemorrhage / Q000139:chemically induced* / Q000175:diagnosis; D002544:Cerebral Infarction / Q000175:diagnosis / Q000188:drug therapy*; D003287:Contrast Media / Q000008:administration & dosage / Q000009:adverse effects*; D003937:Diagnosis, Differential; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D019786:Gadolinium DTPA / Q000009:adverse effects*; D006801:Humans; D007089:Image Enhancement; D007091:Image Processing, Computer-Assisted; D018810:Magnetic Resonance Angiography; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D019047:Phantoms, Imaging; D013345:Subarachnoid Hemorrhage / Q000175:diagnosis; D015912:Thrombolytic Therapy / Q000009:adverse effects*; D010959:Tissue Plasminogen Activator / Q000009:adverse effects*; D014057:Tomography, X-Ray Computed
chemical_list: D003287:Contrast Media; D010959:Tissue Plasminogen Activator; D019786:Gadolinium DTPA