TY - JOUR T1 - Experimental Determination of Dose Calibrator Settings and Study of Associated Volume Dependence in V-Vials for Rhenium-186 Perrhenate Solution Sources JF - Journal of Nuclear Medicine Technology JO - J. Nucl. Med. Technol. SP - 264 LP - 270 VL - 28 IS - 4 AU - Brian E. Zimmerman AU - David W. Pipes Y1 - 2000/12/01 UR - http://tech.snmjournals.org/content/28/4/264.abstract N2 - Objective: Accurate activity measurements of glass conical v-vials are only possible if dose calibrator dial settings are experimentally determined for the specific vial and volume range over which the measurements of a particular radionuclide is to be made. V-vials are used to transport and store unit doses of radiopharmaceuticals containing high-energy beta-emitters, such as 186Re. We have determined the correct dose calibrator dial settings for measuring 186Re in 3-mL glass conical v-vials from 2 manufacturers. Methods: The 186Re solutions used were calibrated for radioactivity content at the National Institute of Standards and Technology (NIST) using liquid scintillation counting with 3H-standard efficiency with a maximum expanded (k = 2) uncertainty of 1.2% on the activity. Volumes of the solutions then were accurately dispensed into a set of v-vials from each of the 2 manufacturers and assayed in the dose calibrator maintained at NIST. Results: For filling volumes above 1 mL, the dose calibrator response was found to be constant for both of the vials studied, enabling a single dial setting to be used for each vial type. The expanded uncertainties on the activity from uncertainty in the dial setting in that volume range were 0.4%–0.7%. Variability in vial construction contributed another 0.2%–0.3% in the uncertainty in the activity determination. Conclusion: These studies indicate a strong volume dependence on the response of the dose calibrator and highlight the need for experimental verification of dose calibrator settings for nonstandard geometries. ER -