Technical Note: Determination of individual thyroid clearance effective half-life with a common handheld electronic dosimeter

Abstract

Purpose: To determine the thyroid clearance effective half-life with a common handheld electronic dosimeter (ED) in patients undergoing radioiodine treatment for hyperthyroidism.Methods: Dose rates from twelve inpatients were measured daily with an ED and with a clinical uptake counter. The ED was attached to the patient with two different setups, one using a cervical collar and another employing a neck strap. Estimation of was performed by linear regression analysis of the log of both the ED and the uptake counter measurements versus time. The latter provided the reference data.Results: Based on repeated neck strap dose rate measurements, individual s were determined with clinically required accuracy. The mean difference from the reference method equaled to -0.090.35 days. Conclusions:Determination of individual is feasible with a common handheld ED using the simple and easy to instruct neck strap measurement setup. This simple method complements stationary uptake counter measurements and thus may improve the accuracy of radioiodine treatment planning by adding an individual for dose calculation..

Prediction of thyroidal 131I effective half-life in patients with Graves' disease

“…It is commonly known that short Teff increases the risk for RIT failure, so it is crucial for GD patients intended to receive RIT therapy to determine Teff before RIT [ 16 ]. However, it is inconvenient to determine Teff directly, which demands 131 I uptake measurements at 24 hours, 48 hours, and 4-6 days, requiring no less than five patient visits over a 5-7 day period, and some authors suggested that up to 10 measurements over a 7-day period are required [ 14 , 15 ]. Based on this, we investigated the factors that could be used to predict Teff and further developed a Teff prediction model in our patient population, which was confirmed to be used more conveniently and practically for our routine work.…”

“…It is commonly known that short Teff increases the risk for RIT failure, therefore, it is crucial for GD patients intended to receive RIT therapy to determine Teff. However, it is often argued that determining Teff is laborious, which requires no less than five patient visits over a 5-7 day period– this makes a novel, highly accurate Teff prediction model very valuable [ 14 , 15 ].…”

A method to measure the absorbed dose of the thyroid during I‐131 therapy, using a collar detector system and a SPECT acquisition

“…Each module is connected to the data acquisition unit and contains a scintillation detector (3 mm × 3 mm active detection surface) faced to the body surface. The use of a comparable device was recently explored by Fürstner et al Example photos of the CoTI are shown in Fig. .…”