Combined parameters estimation for ¹³¹I dosimetry treatment planning in Hyperthyroidism using 2D and 3D

Abstract

Optimization and verification of Specific Patient Treatment Planning with unsealed 131I sources in hyperthyroidism diseases is a desirable goal from medical and radiation protection viewpoints. In order to verify the estimation of patient’s specific treatment dose and his/her related parameters, a combination of 3 different apparatus or pieces of equipment used in nuclear medicine were studied - the Iodine Probe, a Philips Forte Camera with pinhole collimators and a Mediso Nucline with HEGP for planar and SPECT techniques- by using the typical neck phantom and 131I sources simulating diagnosis and treatment procedure. The linear behavior on diagnostic and therapeutic activity range was verified, showing a linear correlation fitting factor R2 > 0,99. The differences between thyroid uptake determinations in all equipment were less than 6 % for therapeutic activities and less than 1,1 % in the diagnostic range. The combined protocol to calculate all the necessary parameters for the patient treatment dose planning using 2D or 3D approach was established and verified, avoiding wasting time with gamma cameras and with only one administration of 131I.

Keywords

• optimización
• dosimetría
• pacientes
• terapia
• yodo 131
• hipertiroidismo
• verificación