Clinical Research Abstracts of the British Equine Veterinary Association Congress 2015.
Authors: Satchell G, McGrath M, Dixon J, Pfau T, Weller R
Journal: Equine veterinary journal
Summary
# Editorial Summary: Standardising Infrared Thermography in Equine Practice Infrared thermography is increasingly used alongside conventional diagnostic techniques in equine medicine, yet questions remain about its reliability under real-world conditions. Satchell and colleagues investigated whether time of day, ambient temperature, and relative humidity systematically influenced thermographic readings by repeatedly imaging 15 sound horses at three time points (08:00, 12:00, and 16:00 hours) across multiple anatomical regions including the carpus, tendons, thoracic and pelvic limbs, and axial skeleton. Significant temperature variations occurred across all regions between imaging sessions, with caudal (distal) areas showing strong correlations to both ambient temperature and humidity, whilst cranial regions proved more stable—a distinction with important implications for monitoring lower limb pathology. Left-right symmetry was generally reliable for clinical comparison, though the carpus and thoracic tendons showed minor asymmetries during morning sessions. These findings underscore the critical need for standardised environmental conditions and consistent timing when using thermography diagnostically; practitioners should document ambient conditions, perform serial comparisons at the same time of day, and exercise caution when interpreting subtle asymmetries, particularly in distal limb structures where environmental variables exert measurable influence.
Read the full abstract on PubMed
Practical Takeaways
- •Standardize thermography timing and environmental conditions (temperature and humidity) when imaging horses, particularly for caudal regions, to ensure reproducible results and valid comparisons over time
- •Be cautious interpreting apparent left-right asymmetry in the carpus and thoracic tendon regions, as these may reflect time-of-day effects rather than pathology
- •Consider environmental factors as confounding variables when using infrared imaging as a diagnostic aid, especially in outdoor or poorly controlled settings
Key Findings
- •Significant differences in thermography readings occurred across three time points (08:00, 12:00, 16:00 h) in all anatomical regions (P<0.014)
- •Ambient temperature and relative humidity significantly correlated with thermography readings in caudal body regions (P<0.008 and P<0.032 respectively) but not cranial regions (P<0.365 and P<0.992)
- •Left-right side symmetry was largely maintained except in carpus and thoracic tendon areas during morning sessions (P=0.033, 0.034)