Radioiodine uptake following iodine-131 therapy for Graves' disease: an early indicator of need for retreatment.
Forty-five patients with Graves' disease were studied prospectively to determine if 24-hour I-131 uptake measurements alone or in combination with serum thyroid hormone levels at six weeks would determine the necessity for retreatment of the thyrotoxicosis. All patients with an I-131 uptake greater than 30% at six weeks required retreatment. No patient with an I-131 uptake of less than 15% required retreatment. Patients with uptakes between 15% and 30% were variable. An elevated free thyroxin index at 6 weeks is not helpful to determine which patients will remain thyrotoxic. Patients with a free thyroxin index within the normal range at six weeks can be predicted to be euthyroid by 12 weeks if their 24-hour I-131 uptake is between 15% and 30% and to be hypothyroid if their 24-hour I-131 uptake is below 15%. There was no difference between patient groups treated initially with antithyroid medication and those who were not.
Carpentier
W R
WR
Department of Radiology, Scott and White Clinic, Temple, Texas 76508.
Gilliland
P F
PF
Piziak
V K
VK
Petty
F C
FC
McConnell
B G
BG
Verdonk
C A
CA
Ibarra
J D
JD
Thompson
J Q
JQ
D000328:Adult; D000368:Aged; D004334:Drug Administration Schedule; D004351:Drug Resistance; D005260:Female; D006111:Graves Disease / Q000000981:diagnostic imaging / Q000378:metabolism / Q000532:radiotherapy*; D006801:Humans; D007457:Iodine Radioisotopes / Q000008:administration & dosage / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011877:Radionuclide Imaging
D007457:Iodine Radioisotopes