Abstract
Introduction Magnetic resonance imaging (MRI) is a valid investigation for the diagnosis of intervertebral disc disease, including infection, but it is expensive and difficult to access conveniently for research studies on live animals under anaesthesia. The aim of this study was to compare the MRI signal changes in spines from living and recently deceased sheep.
Methods MRI was conducted on the lumbar spines of six adult sheep from research studies investigating bacterial discitis, chemical discitis and disc degeneration resulting from annular incision. The sheep was anaesthetised and the lumbar spines were imaged with a Siemens Magneton Vision MRI (Numaris VB33G software) using T1 SGE, T1 FSE, STIR and T2 FSE sequences. The sheep were killed with an intravenous overdose of barbiturate and identical images were obtained commencing five minutes post mortem.
Results For each of the disease processes under consideration the MRI contrast relationships were maintained between all of the anatomical structures of interest. The post-mortem images provided improved clarity, particularly in the STIR and T2-weighted sequences, due to the absence of pulsation from the CSF and aorta, as well as the absence of respiratory artefact.
Discussion The MRI appearances of spinal tissues following death correlate well with those in the live animal confirming the validity of this method of investigation. This is particularly relevant for optimisation of a busy clinical resource for research purposes.
The abstracts were prepared by Professor Bruce McPhee. Correspondence should be addressed to him at Orthopaedics Division, The University of Queensland, Clinical Sciences Building, Royal Brisbane & Women’s Hospital, Herston, Qld, Australia
