AB0751 Semi-automatic quantitative investigation of wrist cartilage in humans using 3t mri

Background Because of its reduced thickness at the carpus level, the MRI identification of cartilage abnormalities has been initially discarded from the usual rheumatologic diagnostic scores and just recently introduced as a qualitative variable related to joint space narrowing. Objectives In the present study we aimed at determining whether carpal cartilage area can be measured using high-field MRI area through a semi-automatic method. We also compared the results related to two different MRI sequences. Methods The study was conducted in 14 healthy volunteers after they provided their written informed consent. MRI investigations were performed at 3T using two 3D sequences i.e. VIBE and DESS for the analysis of carpal cartilage. Cartilage surface was measured on a three-dimensional reconstruction using a conventional image processing radiology software. The protocol received the agreement from the local ethics committee. Results Cartilage measurements performed by two different operators and twice by the same operator showed a very good reproducibility regardless the MRI sequence used. A 15% interindividual variability for the cartilage area was quantified within this control group. Interestingly, the wrist cartilage area was linearly related to the carpal bone height and so for results obtained with both MRI sequences. Conclusions Using high-field MRI, we reported a very reproducible semi-automatic method of cartilage surface measurement in wrist. The measurements were performed on a MRI section accurately defined thanks to 3D acquisitions. The large variability of the corresponding measurements illustrated that cartilage area cannot be used as a stand-alone diagnostic criterion. The standardized linear relationship between wrist cartilage area and carpal bone height captures the natural diversity of these measurements and provides a promising index for future diagnostic and therapeutic studies in the field of rheumatologic diseases. Disclosure of Interest None Declared