title: MR protocols for imaging the guinea pig knee.
abstract: Magnetic resonance images of the femorotibial joints of male Dunkin-Hartley guinea pigs were obtained in two and three dimensions at 2.35 T using a wide range of T1- and T2-weighted imaging sequences. The effect of slice position on visualisation of articular cartilage, bone and periarticular tissues in sagittal and coronal sections was investigated along with the resolution and signal/noise ratio achievable. Based on that survey, a two-dimensional spin echo sequence (repetition time = 1500 ms, echo time = 40 ms) was found to give optimum visualisation of the normal joint anatomy with in-plane resolution of 75 x 150 microns and a 1 mm slice thickness in an imaging time of 25 min. This protocol was also found to be highly effective in distinguishing many features of the spontaneous, osteoarthritic-like pathology found in the joints of older animals compared to juveniles and therefore provides a means of monitoring disease progression longitudinally. Three-dimensional spin echo imaging methods demonstrated focal changes in signal intensity in the articular cartilage of the medial tibial plateau in older animals. The resulting imaging times of several hours, however, precludes their routine use in vivo.
authors.affiliation: Herchel Smith Laboratory for Medicinal Chemistry, University of Cambridge School of Clinical Medicine, UK.
authors.forename: P J
authors.initials: PJ
authors.lastname: Watson
authors.forename: T A
authors.initials: TA
authors.lastname: Carpenter
authors.forename: L D
authors.initials: LD
authors.lastname: Hall
authors.forename: J A
authors.initials: JA
authors.lastname: Tyler
mesh_terms: D000465:Algorithms; D000818:Animals; D002358:Cartilage, Articular / Q000473:pathology; D002985:Clinical Protocols; D004195:Disease Models, Animal; D006168:Guinea Pigs; D007719:Knee Joint / Q000033:anatomy & histology* / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D010003:Osteoarthritis / Q000175:diagnosis*