Changes

=Drawbacks=

=Drawbacks=

Although the RIA is a very sensitive test, and therefore widely-used, there are disadvantages to its use:

Although the RIA is a very sensitive test, and therefore widely-used, there are disadvantages to its use:

*The radioactive substances being used

*The substances being used are radioactive

*Gamma radiation needs special counting equipment for detection

*Gamma radiation needs special counting equipment for detection

*Iodine is naturally concentrated in the thyroid gland, whether radioactive or not, and incorporated into thyroxine

*Iodine is naturally concentrated in the thyroid gland, whether radioactive or not, and incorporated into thyroxine

Consequently, ELISA has largely overtaken RIA as a preferred diagnostic tool

Consequently, ELISA has largely overtaken RIA as a preferred diagnostic tool