title: Evaluation of femoral perfusion in a non-traumatic rabbit osteonecrosis model with T2*-weighted dynamic MRI.
abstract: We evaluated femoral perfusion in a non-traumatic rabbit serum sickness osteonecrosis (ON) model, using serial repetitive T2*-weighted (T2*W) dynamic magnetic resonance imaging (MRI) and investigated prediction of ON occurrence in early stages, comparing T2*W dynamic MRI with non-enhanced (T2-, T1- and fat suppression T1-weighted) and contrast-enhanced MRI. Early microcirculatory injury or necrotic lesion was detected in 0% of femora (extravasation, 0/6) at 72 h, 33% (necrotic, 4/12) at 1 week and 100% (necrotic, 14/14) at 3 weeks using non-enhanced MRI, and in 67% of femora (extravasation, 4/6) at 72 h, 58% (necrotic, 7/12) at 1 week and 100% (necrotic, 14/14) at 3 weeks using contrast-enhanced MRI. In contrast, microcirculatory injury or necrotic lesion was detected in 83% of femora (extravasation, 5/6) at 72 h, 92% (necrotic, 11/12) at 1 week and 100% (necrotic, 14/14) at 3 weeks using T2*W dynamic MRI as no transient decrease or less marked transient decrease in signal intensity of regions of interest (ROIs), compared to normal femora, which showed a clear transient decrease in signal intensity of ROIs. These results indicate that T2*W dynamic MRI with optimal imaging parameters and a dose of contrast agent is the most sensitive of these three MRI methods and may be clinically useful for evaluating femoral perfusion in artery phase and predicting ON occurrence.
authors.affiliation: Diagnostics Research Support, Preclinical Development Department, Nihon Schering, 2-6-64, Nishimiyahara, Yodogawa-ku, Osaka 532-0004, Japan. ttsuji@schering.co.jp
authors.forename: Takashi
authors.initials: T
authors.lastname: Tsuji
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Sugano
authors.forename: Takashi
authors.initials: T
authors.lastname: Sakai
authors.forename: Hideki
authors.initials: H
authors.lastname: Yoshikawa
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005269:Femur / Q000098:blood supply / Q000473:pathology*; D019786:Gadolinium DTPA; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D010020:Osteonecrosis / Q000175:diagnosis* / Q000209:etiology; D011817:Rabbits
chemical_list: D019786:Gadolinium DTPA