TABLE 4

Effect of Thyroid Hormone Replacement and Thyroid Blockade on Net Thyroid Counts on Early and Late 123I-mIBG Imaging

ParameterThyroid hormone replacementNumber of subjectsMean ROI net early thyroid countsMean ROI net decay-corrected late thyroid countsMean net count change% count change
NonblockedNo2058,425 (SD, 7,040)14,733 (SD, 10,423)+6,30874.9
Yes224,012 (SD, 4,057)5,754 (SD, 6,140)+1,74243.4
P = 0.0043P = 0.0001
BlockedNo3999,585 (SD, 9,031)*5,695 (SD, 6,176)†−3,890−40.6
Yes433,908 (SD, 4,547)3,069 (SD, 3,573)−839−21.4
P = 0.0001P = 0.0064

  • ↵* P = 0.11 vs. no/no.

  • ↵† P < 0.0001 vs. no/no.

  • Early = 15 min after administration; late = 3 h 50 min after administration.