Renal uptakes of 99mTc-MAG3, 99mTc-DTPA, and 99mTc-DMSA in rabbits with unilateral ureteral obstruction.

Renal function measurements using (99m)Tc-DTPA and (99m)Tc-MAG(3) dynamic scintigraphs were compared to those obtained using (99m)Tc-DMSA static scintigraphy. Eighteen experimental rabbits were randomly divided into (99m)Tc-DTPA-, (99m)Tc-MAG(3)-, and (99m) Tc-DMSA-injected groups. Experimental unilateral renal damage was induced by ligating a unilateral right ureter in 18 rabbits. Scintigraphic images were obtained at 2 and 5 h after intravenous injection of (99m)Tc-DMSA, or immediately after administration of (99m)Tc-DTPA or (99m)Tc-MAG(3). For the dynamic images using (99m)Tc-DTPA and (99m)Tc-MAG(3), rapid sequential images were obtained every 2 s for 30 images up to 1 min. The three groups presented different relative renal functions between the left normal and the right abnormal kidneys at 1, 2, 3, and 4 weeks post-ligation (p<0.05). However, the between-group comparisons showed no significant differences at any time. These results suggest that dynamic images of (99m)Tc-DTPA and (99m)Tc-MAG(3) can be used to measure the relative renal function in place of the static image of (99m)Tc-DMSA.

Scintigraphic evaluation of TPLO and CTWO in canine osteoarthritis.

The objective of this study was to evaluate the bone uptake of the bone-seeking radionuclide (99m)technetium-methylene diphosphonate ((99m)Tc-MDP) in order to examine and compare the clinical efficacies of tibial plateau leveling osteotomy (TPLO) and cranial tibial wedge osteotomy (CTWO) for the correction of experimentally induced cranial cruciate ligament (CrCL) transected stifle. Fifteen healthy adult beagle dogs, weighing between 10 and 15 kg, were used for this study. Dogs were assigned to TPLO (n=5), CTWO (n=5) or a control sham group (n =5) and screened with both physical and complete orthopedic examinations. Left CrCLs were transected and two of the three groups were stabilized using TPLO and CTWO. Scintigraphic evaluation of the stifle was performed before TPLO or CTWO surgical repair of the left limb and again at 4, 8 and 12 weeks after surgery. Bone uptake values at 8 and 12 weeks for the TPLO and CTWO groups were not significantly different from their preoperative values, but these differed significantly from the control group at 4, 8 and 12 weeks (p<0.01). No significant differences were found between TPLO and CTWO values. In summary, the relative efficacy of CTWO approximately equals that of TPLO. Moreover, the results of this study confirmed that TPLO and CTWO inhibited the progression of osteoarthritis in CrCL-deficient dogs.

Comparison of the effect of 99mTc-DPD and 99mTc-MDP on experimentally-induced osteoarthritis in the stifle joint of the dog.

This study was designed to evaluate the effect of 99mTechnetium-dicarboxypropane diphosphonate (99mTc-DPD) and 99mTechnetium-methylene diphosphonate (99mTc-MDP) on bone scan image quality and time in dogs with osteoarthritis. The left cranial cruciate ligament (CrCL) in ten healthy adult Beagle dogs was transected under general anesthesia. The dogs were assigned to 99mTc-DPD-injected or 99mTc-MDP-injected groups. Stifle joint scintigraphy was performed after intravenous injection of 10 mCi 99mTc-DPD or 99mTe-MDP. Scintigraphy was conducted before CrCL transection and 2, 4, 6, 8, 10 and 12 weeks after the procedure. There were no significant differences in density, sensitivity and pathological foci between the 99mTc-DPD and 99mTc-MDP groups of experimentally-transected CrCL dogs. A comparison of the images obtained with Pinhole type and low energy general purpose type collimators of the stifle joint of normal dogs and after CrCL transaction revealed no significant differences in bone radioactivity. Scintigraphs were obtained 3 h after 99mTc-MDP and 2 h after 99mTc-DPD injection. In conclusion, application of 99mTc-DPD and 99mTc-MDP in experimentally-induced osteoarthritis of the stifle joint in dogs results in similar effects on radioactive uptake ratio and image quality. 99mTc-DPD is more efficient than 99mTc-MDP in reducing the overall time of scintigraphy.