Determination of radioiodine uptake in thyroids by two methods.

Abstract

There are several methods available for the determination of radioiodine (I131) uptake by the thyroid gland. Some methods involve a single detector, either a scintillation counter or a Geiger-Muller tube, or four detectors, either scintillation counters or Geiger-Muller tubes. There are advantages and disadvantages in both methods. Since both a single scintillation counter and a four-tube setup are in use at the New England Deaconess Hospital, it was decided to compare the uptake of I131in the thyroid gland as determined by each method. Radioiodine emits beta particles, having a maximum energy of 0.60 mev and a range in tissue of 2 to 3 mm.; the I131also emits gamma rays. This isotope has a half-life of eight days. Since the I131normally concentrates in the thyroid gland in varying amounts, depending on the condition of the gland, the isotope is very useful in diagnostic tests.