Radiation from the equine perineal region is low compared with the elbow and head 24 hours after bone scintigraphic examination

Abstract

The timing of follow-up radiography and ultrasound in horses that undergo skeletal scintigraphy for lameness investigation varies internationally and between equine hospitals. The prospective, one-group, pretest, posttest study aimed to estimate radiation levels from horses three and 24 h after injection of hydroxydiphosphonate labeled with metastable technetium (99mTc-HDP) and investigate which anatomical locations of the horse had higher radiation levels. Included were 46 horses referred for lameness investigation between June and December 2021. Radiation levels from the horse surface were measured using an electronic device from six anatomical locations (head, elbow, dorsum, ventrum, stifle, and perineum) at two time points and adjusted to three and 24 h after injection of 99mTc-HDP using the radioactive decay law. The radiation measured was significantly different in the various locations of the horses for both time points. At 3 h after injection of 99mTc-HDP, the ventrum had the highest radiation dose. At 24 h, the radiation emitted from the perineal region was significantly lower (P