TY - JOUR
T1 - MR imaging of hemorrhagic brain lesions
T2 - A comparison of dual-echo gradient- and spin-echo and fast spin-echo techniques
AU - Melhem, Elias R.
AU - Patel, Rupa T.
AU - Whitehead, Richard E.
AU - Bhatia, Rita G.
AU - Rockwell, David T.
AU - Jara, Hernan
PY - 1998/9
Y1 - 1998/9
N2 - OBJECTIVE. Our objective was to assess the usefulness of the dual-echo gradient- and spin-echo (GRASE) technique in revealing acute hemorrhagic brain lesions and compare GRASE and fast spin-echo techniques for revealing acute hemorrhagic lesions and image artifacts. MATERIALS AND METHODS. Thirty- two consecutive patients with acute intracranial hemorrhage underwent dual- echo GRASE (TE(eff1)/TE(eff2), 35/85) and fast spin-echo (25/110) imaging. The techniques were matched for TR (3032 msec), spatial resolution, and acquisition time. Two neuroradiologists reviewed the images independently, documenting the number, size (<1, >1, or 1 cm in diameter), location, and signal characteristics (hypointense versus hyperintense compared with brain)of detectable lesions. These observers also compared matched T2- and proton density-weighted GRASE and fast spin-echo images for paramagnetic lesion conspicuity, diamagnetic susceptibility artifacts, chemical shift artifacts along the phase- and frequency-encoding directions, and artifactual CSF hyperintensity in the thin curvilinear cortical sulci and the Virchow- Robin spaces on only the proton density-weighted images. RESULTS. The average number and conspicuity of dark (paramagnetic) lesions were significantly greater on GRASE than on fast spin-echo images (p < .05 and p < .001, respectively). We found no significant difference in the average number of bright lesions revealed by either technique (p >. 1). Chemical shift artifacts along the phase-encoding directions were more prominent on GRASE than on fast spin-echo imaging. Chemical shift artifacts along the frequency- encoding directions and artifactual CSF hyperintensity were more prominent on fast spin-echo than on GRASE imaging. No visually apparent difference was found in the degree of diamagnetic susceptibility artifacts seen with the two techniques. CONCLUSION. Dual-echo GRASE imaging can be helpful in the examination of patients with suspected acute brain hemorrhage.
AB - OBJECTIVE. Our objective was to assess the usefulness of the dual-echo gradient- and spin-echo (GRASE) technique in revealing acute hemorrhagic brain lesions and compare GRASE and fast spin-echo techniques for revealing acute hemorrhagic lesions and image artifacts. MATERIALS AND METHODS. Thirty- two consecutive patients with acute intracranial hemorrhage underwent dual- echo GRASE (TE(eff1)/TE(eff2), 35/85) and fast spin-echo (25/110) imaging. The techniques were matched for TR (3032 msec), spatial resolution, and acquisition time. Two neuroradiologists reviewed the images independently, documenting the number, size (<1, >1, or 1 cm in diameter), location, and signal characteristics (hypointense versus hyperintense compared with brain)of detectable lesions. These observers also compared matched T2- and proton density-weighted GRASE and fast spin-echo images for paramagnetic lesion conspicuity, diamagnetic susceptibility artifacts, chemical shift artifacts along the phase- and frequency-encoding directions, and artifactual CSF hyperintensity in the thin curvilinear cortical sulci and the Virchow- Robin spaces on only the proton density-weighted images. RESULTS. The average number and conspicuity of dark (paramagnetic) lesions were significantly greater on GRASE than on fast spin-echo images (p < .05 and p < .001, respectively). We found no significant difference in the average number of bright lesions revealed by either technique (p >. 1). Chemical shift artifacts along the phase-encoding directions were more prominent on GRASE than on fast spin-echo imaging. Chemical shift artifacts along the frequency- encoding directions and artifactual CSF hyperintensity were more prominent on fast spin-echo than on GRASE imaging. No visually apparent difference was found in the degree of diamagnetic susceptibility artifacts seen with the two techniques. CONCLUSION. Dual-echo GRASE imaging can be helpful in the examination of patients with suspected acute brain hemorrhage.
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U2 - 10.2214/ajr.171.3.9725319
DO - 10.2214/ajr.171.3.9725319
M3 - Article
C2 - 9725319
AN - SCOPUS:0031723432
VL - 171
SP - 797
EP - 802
JO - The American journal of roentgenology and radium therapy
JF - The American journal of roentgenology and radium therapy
SN - 0361-803X
IS - 3
ER -