title: Quantitative evaluation of bone scintigraphy of the spinous processes of the equine thoracic spine at different times after administering ⁹⁹mTc-hydroxymethylene-diphosphonate.
abstract: Scintigraphic examination of the thoracic spine is well documented. However, there is limited information about the effects of time on image quality in the period following injection of radionuclide. This study aimed to determine the optimal time point after injection of (99m)Tc-HDP (hydroxymethylene-diphosphonate) to achieve scintigraphic images with the best possible contrast and adequate count rates. Scintigraphic images of the thoracic spine of 21 horses were acquired two, four and six hours after administering (99m)Tc-HDP. Eight regions of interest were drawn in the images, four in the spinous processes and four in the adjacent soft tissue. The bone uptake, soft tissue uptake and the bone-to-soft tissue ratio were determined and compared between the different time points. Total count rates decreased with time after injection, but were at least as high as 150,000 counts per image at every time point after injection. The bone-to-soft tissue ratio was significantly higher for the images acquired after six hours compared to those acquired after two and four hours (P<0.01). Delayed scintigraphic examinations of the spinous processes of the equine thoracic spine achieved images with high contrast and sufficient count rates. Therefore, the scintigraphic examination of the equine thoracic spine is recommended to be done four to six hours after injecting (99m)Tc-HDP. However, additional studies should be performed to determine the effect of delayed image acquisition compared to images taken after three hours on the detectability of lesions in other parts of the thoracic spine and the soft tissue.
authors.affiliation: Faculty of Veterinary Medicine, University of Leipzig, Large Animal Clinic for Surgery, Leipzig, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Sporn
authors.affiliation: Faculty of Veterinary Medicine, University of Leipzig, Large Animal Clinic for Surgery, Leipzig, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Berner
authors.affiliation: University of Leipzig, Translational Centre for Regenerative Medicine (TRM), Leipzig, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Winter
authors.affiliation: Faculty of Veterinary Medicine, University of Leipzig, Large Animal Clinic for Surgery, Leipzig, Germany; Faculty of Veterinary Medicine, Department of Surgery and Anaesthesiology Khartoum, University of Khartoum, Khartoum, Sudan.
authors.forename: M
authors.initials: M
authors.lastname: Mageed
authors.affiliation: Faculty of Veterinary Medicine, University of Leipzig, Large Animal Clinic for Surgery, Leipzig, Germany.
authors.forename: W
authors.initials: W
authors.lastname: Brehm
authors.affiliation: Faculty of Veterinary Medicine, University of Leipzig, Large Animal Clinic for Surgery, Leipzig, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Gerlach
mesh_terms: D000818:Animals; D005260:Female; D006734:Horse Diseases / Q000000981:diagnostic imaging; D006736:Horses; D008297:Male; D011877:Radionuclide Imaging / Q000379:methods / Q000662:veterinary; D019275:Radiopharmaceuticals; D013122:Spinal Diseases / Q000000981:diagnostic imaging / Q000662:veterinary; D013131:Spine / Q000000981:diagnostic imaging*; D013669:Technetium Tc 99m Medronate / Q000031:analogs & derivatives*; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging*; D013997:Time Factors
chemical_list: D019275:Radiopharmaceuticals; C024226:technetium Tc 99m hydroxymethylene diphosphonate; D013669:Technetium Tc 99m Medronate