Artificial multiple sclerosis lesions on simulated FLAIR brain MR images: echo time and observer performance in detection.
The institutional review board approved the described HIPAA-compliant study, which was performed to prospectively evaluate observer performance in the detection of artificial multiple sclerosis (MS) lesions that were randomly distributed supra- and infratentorially on simulated fluid-attenuated inversion-recovery (FLAIR) magnetic resonance (MR) images obtained at different echo times (TEs). MR parametric maps were derived from mixed multi-echo inversion-recovery images obtained in a 40-year-old healthy male volunteer and in a patient with MS, both of whom gave informed consent. Pseudo-randomly distributed artificial MS lesions of varying size, number, and location were equally represented on the FLAIR images (11 000/100-200/2600 [repetition time msec/TE msec/inversion time msec]). Twelve images obtained in both regions at each of 11 TEs spaced 10 msec apart were rated by seven neuroradiologists by using a four-point scale. Observer performance in the detection of MS lesions on the FLAIR images, as estimated by using areas under the alternative free-response receiver operating characteristic curve, was highest and most consistent at the 100-msec TE, both supratentorially (93.0% +/- 8.6 [standard error of the mean]) and infratentorially (87.4% +/- 10.0).
Pikus
Lana
L
Department of Radiology, Hospital of the University of Pennsylvania, 3400 Spruce Street, Dulles 2, Philadelphia, PA 19104, USA.
Woo
John H
JH
Wolf
Ronald L
RL
Herskovits
Edward H
EH
Moonis
Gul
G
Jawad
Abbas F
AF
Krejza
Jaroslaw
J
Melhem
Elias R
ER
D000328:Adult; D003198:Computer Simulation; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000592:standards; D009103:Multiple Sclerosis / Q000175:diagnosis*; D011446:Prospective Studies; D013997:Time Factors