Equine skeletal scintigraphy: Comparing lesion detection ability of methylene diphosphonate and hydroxymethylene diphosphonate in the caudal cervical and proximal metacarpal/metatarsal regions.

BACKGROUND: Data regarding the lesion detection ability of different radiotracers are lacking in equine bone scintigraphy. METHODS: In this prospective study, hydroxymethylene diphosphonate (HMDP) and methylene diphosphonate (MDP) were compared in horses with increased radiopharmaceutical uptake either in the caudal cervical region (CS group) or in the proximal metacarpal/metatarsal region (PMR group). Region of interest analysis was used to determine normal bone-to-soft tissue ratios, lesion-to-normal bone ratios and lesion-to-soft tissue ratios. Qualitative scoring and total count rates were recorded for each image. RESULTS: A total of 213 scintigrams were included. Within the PMR group, there were significantly higher lesion-to-normal bone ratios for MDP compared with HMDP (p = 0.02). In the CS group, normal bone-to-soft tissue ratios were significantly higher for HMDP (p = 0.01). The interobserver agreement with regard to the qualitative assessment of the scintigrams was poor. LIMITATION: Paired studies, comparing the different radiotracers in the same patient, were not feasible. CONCLUSION: This study revealed minor differences between the two radiotracers, although these have no practical implications. Both radiopharmaceuticals are well suited for detecting lesions at the investigated sites using equine bone scintigraphy.

Comparison between head-tail-rope assisted and unassisted recoveries in healthy horses undergoing general anesthesia for elective surgeries.

OBJECTIVE: To compare attempts to stand, duration, quality, and occurrence of injuries between head-tail rope assistance and unassisted recoveries in healthy horses undergoing general anesthesia for elective surgeries. STUDY DESIGN: Randomized, prospective, clinical trial. METHODS: Three hundred one healthy horses undergoing elective surgeries were randomly assigned to recover with head-tail rope assistance (group A) or unassisted (group U); 305 recoveries (group A, n = 154; group U, n = 151) were analyzed. Anesthesia was maintained with isoflurane and triple drip. For each recovery, attempts to stand, duration, quality, and recovery-associated injuries were recorded. Data were analyzed by linear regression and analysis of covariance. RESULTS: Anesthesia duration was similar between groups (mean ± SD, 70 ± 29 minutes). Compared with group U, group A had fewer attempts to stand (median [range], group A = 1 [1-7] vs group U = 3 [1-34]) and shorter duration of recovery (mean ± SD, A = 36 ± 12 minutes vs U = 41 ± 15 minutes). Recovery quality in group A (28 points [15-70]) was better than that in group U (38 points [11-87]). More horses had recovery-associated injuries in group U (9 horses) compared with group A (2 horses). One horse per group was euthanized. CONCLUSION: Head-tail rope assistance reduced standing attempts, shortened recovery duration, improved recovery quality, and reduced recovery-associated minor injuries after general anesthesia for elective surgery in healthy horses. Fatalities could not be prevented. CLINICAL SIGNIFICANCE: Head-tail rope assistance may improve recovery in healthy horses after short-duration elective surgeries with isoflurane and triple drip.