Radiology, Vol 147, 793-795, Copyright © 1983 by Radiological Society of North America
Thyroid CT number and its relationship to iodine concentration
Y Iida, J Konishi, T Harioka, T Misaki, K Endo and K Torizuka
Sixty-seven patients with thyroid disease and 24 normal controls were
examined with computed tomography (CT). The mean CT number (Hounsfield
units +/- SD) in the normal controls (118.1 +/- 12.2) was significantly
higher (p less than 0.001) than the mean CT number in patients with
diseased thyroids, except for 2 cases of simple goiter (CT numbers 113,
132). The mean CT numbers in the patients with Graves disease (69.5 +/-
17.6) and Hashimoto thyroiditis (61.4 +/- 9.1) were significantly higher
than those in patients with adenoma (41.7 +/- 10.6, p less than 0.001),
cyst (33.1 +/- 14.8, p less than 0.001), or cancer (48.7 +/- 13.0, p less
than 0.01). In 14 patients studied, a significant correlation was observed
between thyroid CT numbers and the iodine concentration of the tissue (r =
0.889; p less than 0.001).
