Published in:
01-08-2007 | Original Article
Early detection and monitoring of cartilage alteration in the experimental meniscectomised guinea pig model of osteoarthritis by 99mTc-NTP 15-5 scintigraphy
Authors:
Elisabeth Miot-Noirault, Aurélien Vidal, Philippe Pastoureau, Jacques Bonafous, Agnès Chomel, Laurent Sarry, Laurent Audin, Jean-Claude Madelmont, Nicole Moins
Published in:
European Journal of Nuclear Medicine and Molecular Imaging
|
Issue 8/2007
Login to get access
Abstract
Purpose
This study in the meniscectomised guinea pig aimed to demonstrate that the radiotracer 99mTc-NTP 15-5 would have pathophysiological validity for in vivo osteoarthritis imaging.
Methods
The specificity of 99mTc-NTP 15-5 for cartilage was determined in healthy animals (n = 13), by tissue radioactivity counting, joint autoradiography and scintigraphy. 99mTc-NTP 15-5 scintigraphy was performed at 20, 50, 80, 115, 130, 150 and 180 days after medial meniscectomy (n = 10 MNX) or sham operation (n = 5), and scintigraphic ratios (operated/contralateral) were calculated for femoral (F) and tibial (T) areas. F and T ratios were compared with those of 99mTc-MDP bone scintigraphy. At the study end-point, autoradiographic analysis of joint 99mTc-NTP 15-5 distribution and macroscopic scoring of cartilage integrity were performed.
Results
The high and specific accumulation of 99mTc-NTP 15-5 in normal cartilage (about 5.5 ± 1.7 % of injected dose/g of tissue), which permitted joint imaging with high contrast, was affected by osteoarthritis. In the MNX group, 99mTc-NTP 15-5 accumulation in cartilage within the operated joint, relative to the contralateral joint, was observed to change in the same animals as pathology progressed. Although F and T ratios were significantly higher in MNX (F = 1.7 ± 0.2; T = 1.6 ± 0.1) than in shams (F = 1.0 ± 0.1; T = 1.0 ± 0.1) at day 50, they were significantly lower in MNX (F = 0.6 ± 0.1; T = 0.7 ± 0.1) than in shams (F = 1.0 ± 0.1; T = 0.9 ± 0.1) at day 180. No change in 99mTc-MDP uptake was observed over 6 months. Macroscopic analysis confirmed features of osteoarthritis only in MNX knees.
Conclusion
These results in MNX guinea pigs provide additional support for the use of 99mTc-NTP 15-5 for in vivo imaging of osteoarthritis.