RT Journal Article SR Electronic T1 Assessment of 99mTc-Succimer Residual Activity Using Inert Nonreactive Syringes JF Journal of Nuclear Medicine Technology JO J. Nucl. Med. Technol. FD Society of Nuclear Medicine SP 61 OP 63 DO 10.2967/jnmt.114.147983 VO 43 IS 1 A1 Wendy Galbraith A1 Xinlian Chen A1 Katie Talley A1 Vesper Grantham YR 2015 UL http://tech.snmjournals.org/content/43/1/61.abstract AB It has been widely reported that 99mTc-succimer adsorbs to plastic syringes significantly (up to 50%), often resulting in a lower administered dose than intended or inaccurate dosing. This adsorption rate is especially problematic in the pediatric population. To improve 99mTc-succimer dosing, we compared the adsorption of 99mTc-succimer with 2 types of syringes: silicone-coated syringes with nonlatex rubber on the plunger and inert nonreactive syringes with no silicone coating and no rubber on the plunger. Methods: 99mTc-succimer kits were compounded according to the manufacturer’s instructions. 99mTc-succimer doses (37–185 MBq) were drawn into 3-mL (silicone-coated or inert nonreactive) syringes in a 1-mL volume. Thirty min, 1 h, 2 h, and 4 h later, the syringes were assayed in a dose calibrator and assayed again after being emptied and rinsed with saline. In addition, we examined the data collected from 129 99mTc-succimer doses administered in a pediatric department, in which 52 were dispensed in silicone-coated syringes and 77 were dispensed in inert nonreactive syringes. The doses were assayed immediately before and after injection. The syringes were flushed with normal saline. Results: The labeling efficiency of the 99mTc-succimer kits was more than 95%. Residual activity left in the inert nonreactive syringes was 0.73% (SD, ±0.18%), which was significantly lower than the activity left in the silicone-coated syringes, 20.9% (SD, ±5.6%; P < 0.0001). The extent of adsorption did not change significantly between 30 min and 4 h of incubation. The clinical data showed that the residual activity was 30.6% (SD, ±12.5%) from doses dispensed in silicone-coated syringes and 6.38% (SD, ±2.95%) from doses dispensed in inert nonreactive syringes (P < 0.001). Conclusion: The inert nonreactive syringes had significantly less residual of 99mTc-succimer than silicone-based syringes, making it possible to accurately administer calculated doses of 99mTc-succimer to pediatric patients.