Chapter 19, Problem 59A

Interpretation Introduction

Interpretation: The use of radioisotopes $I$ and $Tl$ in medical diagnosis or treatment of diseases with reasoning needs to be explained.

Concept introduction: An isotope is an atom that has the different number of neutrons but same number of protons. Radioisotopes can be defined as an atom which have an unstable nucleus and readily undergoes radioactive decay.

Radioisotopes have wide application in medical diagnosis or treatment of diseases.

Answer to Problem 59A

To treat thyroid $I$ is used. To treat cardiac damage $Tl$ is used.

Explanation of Solution

  $I$ is used in diagnosis as well as treatment of thyroid cancer. The thyroid will absorb iodine to produce the iodine-containing thyroid hormones. A hyperactive thyroid gland will absorb the radioactive material which can then destroy excess thyroid tissue or any cancer of the thyroid.

  $Tl$ decays by electron capture process. It also emits low intensity gamma ray which makes the radiation damage fairly negligible. It remains in the body for some time because its half-life is about seventy three hours. $Tl$ is used to diagnose cardiac damage or myocardial perfusion imaging (MPI). This test that shows how well blood flows through our heart muscle. $Tl$ flows in the blood stream; if there is less blood flow in the heart, then concentration of the isotope will be low in heart muscle.

Conclusion

To treat thyroid $I$ is used. To treat cardiac damage $Tl$ is used.