Skeletal Imaging
Medical imaging has long been a strength in Aberdeen, perhaps most famous for the development of the first whole-body Magnetic Resonance (MR) imager to be used clinically. In addition to traditional MR imaging, Aberdeen is home to the only positional MR scanner in the UK. This is a Fonar Indomitable ä 0.6 T scanner in which individuals can be imaged in the upright, as well as the conventional horizontal, position.Using this we have used active shape modelling to show that each individual has an innate shape to their lumbar spine that is preserved through many postures. We are currently using these techniques to investigate whether this innate shape may predispose to injury.
For the assessment of osteoporosis, dual-energy x-ray absorptiometry (DXA) is still the "gold standard". Aberdeen is a leading centre for research into this disease and DXA is fundamental to a number of patient-based studies. Current studies are using the latest Lunar iDXA imager from GE Healthcare. Recently we have been using active shape modelling and developing novel methods for texture analysis to improve the information obtainable from radiographs and DXA images (http://www.abdn.ac.uk/orthopaedics/res_boneshape.shtml). These appear to promise powerful new imaging biomarkers for identifying individuals at greatest risk of hip fracture from osteoporosis and those likely to develop osteoarthritis . http://www.abdn.ac.uk/orthopaedics/research.shtml.
There are many different styles of hip replacements and despite several decades of use it is still not clear which might be the best or, even, how they work mechanically. The average lifetime of an implant is still only about 15 years. Excessive migration of prosthetic hips is one factor that can lead to premature failure. The movement of different types of implant is being studied using stereo-radiography to build a 3D picture of the position of the implant.
Electron and optical microscopy are fundamental to many of the studies being performed on osteoclasts, osteoblasts and osteocytes. Micro-computed tomography (µCT) is being used to study trabecular architecture in three dimensions with a resolution of better than 10 µm (http://www.abdn.ac.uk/orthopaedics/res_3dm_mct.shtml). In collaboration with colleagues in Chemistry we have a Fourier-transform infra-red microscope and a Raman confocal microscope to characterise the local chemical composition and structure of bone.
Personnel include Dr Paddy Ashcroft, Prof Richard Aspden, Prof Fiona Gilbert, Dr Jenny Gregory, Dr Jude Meakin.
Selected publications
J.R. Meakin, J.S. Gregory, F.W. Smith, F.J. Gilbert and R.M. Aspden. Characterising the shape of the lumbar spine using an active shape model: reliability and precision of the method. Spine 33: 807-813, 2008.
J.S. Gregory, J.H. Waarsing, J. Day, H.A. Pols, M. Reijman, H. Weinans, R.M Aspden. Early identification of osteoarthritis of the hip from radiographs using an active shape model to quantify changes in bone morphometry: a prospective study. Arthritis and Rheumatism 56: 3634-3643, 2007. Doi: 10.1002/art.22982
M. M. Tilanus-Linthorst, I. M. Obdeijn, W. C. Hop, P. A. Causer, M. O. Leach, E. Warner, L. Pointon, K. Hill, J. G. Klijn, R. M. Warren, and F. J. Gilbert. BRCA1 mutation and young age predict fast breast cancer growth in the Dutch, United Kingdom, and Canadian magnetic resonance imaging screening trials. Clin.Cancer Res. 13:7357-7362, 2007.
F. J. Gilbert, S. M. Astley, M. A. McGee, M. G. Gillan, C. R. Boggis, P. M. Griffiths, and S. W. Duffy. Single reading with computer-aided detection and double reading of screening mammograms in the United Kingdom National Breast Screening Program. Radiology 241 (1):47-53, 2006.
N. Forrest, A. Welch, A. D. Murray, L. Schweiger, J. Hutchison, and G. P. Ashcroft. Femoral head viability after Birmingham resurfacing hip arthroplasty: assessment with use of [18F] fluoride positron emission tomography. J.Bone Joint Surg.Am. 88 Suppl 3:84-89, 2006.
S. I. Semple, R. T. Staff, S. D. Heys, T. W. Redpath, A. E. Welch, T. S. Ahearn, A. Hutcheon, and F. J. Gilbert. Baseline MRI delivery characteristics predict change in invasive ductal breast carcinoma PET metabolism as a result of primary chemotherapy administration. Ann Oncol. 17 (9):1393-1398, 2006.
J.S. Gregory, A. Stewart, P.E Undrill, D.M. Reid and R.M Aspden. Bone shape, structure and density as determinants of osteoporotic hip fracture: A pilot study investigating the combination of risk factors. Investigative Radiology 40: 591-597, 2005.
S. Rahmatallah, Y. Li, H.C. Seton, I.S. Mackenzie, J.S. Gregory and R.M. Aspden. NMR detection and one-dimensional imaging using the inhomogeneous magnetic field of a portable single-sided magnet. Journal of Magnetic Resonance 173: 23-28, 2005. Doi: 10.1016/j.jmr.2004.11.014.
Stewart A, Kumar V, Torgerson DJ, Fraser WD, Gilbert FJ, Reid DM.. Axial BMD, change in BMD and bone turnover do not predict breast cancer incidence in early postmenopausal women. Osteoporosis International, 16: 1627-1632, 2005.
Goh KL, Hiller J, Haston JL, Holmes DF, Kadler KE, Murdoch A, Meakin JR, Wess TJ. 2005. Analysis of collagen fibril diameter distribution in connective tissues using small-angle X-ray scattering. Biochimica et Biophysica Acta - General Subjects 1722: 183-188, 2005
J.S. Gregory, A. Stewart, P.E Undrill, D.M. Reid and R.M Aspden. Identification of hip fracture patients from radiographs using Fourier analysis of the trabecular structure: a cross-sectional study. BMC Medical Imaging, 4:4, 2004. Doi:10.1186/1471-2342-4-4.
J.S. Gregory, D. Testi, A. Stewart, P.E. Undrill, D.M. Reid and R.M. Aspden. A method for assessment of the shape of the proximal femur and its relationship to osteoporotic hip fracture. Osteoporosis International 15: 5-11, 2004.
Gilbert FJ, Grant AM, Gillan MG, Vale L, Scott NW, Campbell MK, Wardlaw D, (...), Porter RW.. Does early imaging influence management and improve outcome in patients with low back pain? A pragmatic randomised controlled trial. Health technology assessment (Winchester, England), 8 (17), Pages iii, 1-131, 2004.
Gilbert FJ, Grant AM, Gillan MGC, Vale LD, Campbell MK, Scott NW, Knight DJ, Wardlaw D. Low Back Pain: Influence of Early MR Imaging or CT on Treatment and Outcome - Multicenter Randomized Tria.l Radiology 231: 343-351, 2004.
Garratt AM, Brealey S, Gillespie WJ; DAMASK Trial Team. Patient-assessed health instruments for the knee: a structured review. Rheumatology 43: 1414-23, 2004