Accuracy and Reproducibility of Seven Brands of Small-Volume Syringes Used for Intraocular Drug Delivery

Abstract

BACKGROUND AND OBJECTIVE: Little is known about the accuracy and precision of syringes used to deliver small-volume intravitreal injection of medication. The authors investigated the accuracy and reproducibility of seven brands of small-volume syringes used for intravitreal injection. MATERIALS AND METHODS: This experimental laboratory investigation compared EXELint 1 cc TB, BD Luer-lok, BD 1 cc TB, Kendall Monoject TB, Nipro TB, Terumo 1 cc, and Terumo 0.5 cc syringes. A calibrated Pipetman served as a control. One hundred syringes of each brand delivered 0.05 mL and 0.10 mL distilled water onto a balance. One-sample t-test (P < .01) compared delivered and intended volumes. RESULTS: The Nipro TB was the most accurate syringe at 0.05 mL. All other brands over-delivered the target volume. At 0.10 mL, the BD Luer-lok and Nipro TB were the most accurate. BD Luer-lok over-delivered while Nipro TB under-delivered, but these deviations were not statistically significant. The Pipetman control was the most accurate and reproducible device at both volumes. CONCLUSION: Nipro TB was the most accurate syringe at both volumes. Terumo 0.5 cc gave the most reproducible results but lacked accuracy. These findings may affect treatment efficacy and explain variability in treatment responses. Industry-standardized delivery devices may increase the accuracy and reproducibility of medication delivery.