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).
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.
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).
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.
From the *Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea; †Department of Radiology, Kangwon National University College of Medicine, Chunchon, Korea; ‡Department of Radiology, Research Institute of Radiologic Science, Yonsei University College of Medicine, Seoul, Korea; §Department of Radiology, Seoul National University College of Medicine, Seoul, Korea; ∥Department of Radiology, Gyeongsang National University College of Medicine, Jinju-Si, Korea; and ¶Department of Radiology, School of Medicine, Catholic University of Daegu, Daegu, Korea.
Received for publication September 5, 2004; accepted January 3, 2005.
Reprints: Soo Kim, Department of Radiology, Kangwon National University Hospital, 17-1 Hyoja 3-dong, Chunchon, Kangwon-do 200-947, Korea (e-mail: firstname.lastname@example.org).