Recombinant human thyroid-stimulating hormone versus thyroid hormone withdrawal in the identification of metastasis in differentiated thyroid cancer with 131I planar whole-body imaging and 124I PET.

Unlabelled: Various studies have compared the detection of functioning residual thyroid tissue after thyroidectomy using radioiodine whole-body (WB) imaging following preparation of patients with injections of recombinant human thyroid-stimulating hormone (rhTSH) and thyroid hormone withdrawal (THW). However, metastases may have radiopharmacokinetics different from normal thyroid tissue. The objective of this study was to evaluate these 2 methods of patient preparation for the detection of metastases from differentiated thyroid cancer (DTC) using (131)I WB imaging and (124)I PET.

Standardization and quantification of radionuclide solid gastric-emptying studies.

Unlabelled: The purposes of this investigation were to standardize and validate a simple quantitative method for performing radionuclide solid gastric emptying that can be used for any dual-head gamma-camera and to establish reference values.

Methods: After eating a solid meal (egg sandwich) labeled with a radionuclide, 20 healthy volunteers (9 male, 11 female) underwent a 90-min gastric-emptying study performed with a triple-head gamma-camera. Two sets of 3 simultaneous projections were acquired sequentially for 30 s each: anterior, right posterior oblique (RPO), left posterior oblique (LPO), posterior, left anterior oblique (LAO), and right anterior oblique (RAO), and this sequence was repeated continuously for 90 min.