Free Thyroxine Index High. The free thyroxine index (fti) is determined by the following calculation: A high tsh level indicates that the thyroid gland is not making enough thyroid hormone (primary hypothyroidism).
The t3/thyroxine ratio, an index of free t3 concentration, increased much more rapidly on the high than on the low glucose diet. The free thyroxine index (fti) is determined by the following calculation: The free thyroxine index (fti) is determined by the following calculation:
The scientific validity of this index is debatable as the index is relative (results are related to a normal control) and is imprecise (containing two ratios).
Elevated free thyroxine levels may indicate hyperthyroidism, thyroid hormone resistance syndrome, or thyroxine toxicosis. Fti (free thyroxine index, fti, t7) the fti is obtained by multiplying the (total t4) times (t3 uptake) to obtain an index. If during the t3 uptake test, the total t4 elevated, free t4 normal, tsh normal, t3 uptake low, this indicates a problem with. Free thyroxine index is considered to be a reliable indicator of thyroid status in the presence of abnormalities in plasma protein binding.
