Q. Illustrate Thallium Scintigraphy?
It is often done with SPECT (single photon emission computed tomography) which further increases the sensitivity. However, a stress test with thallium is costly and has the undesirable side effect of exposure to radiation. A total body radiation exposure associated with intravenous injection of 2mCi of thallium-201 is approximately 420 mrad; this amount is equivalent to that of approximately 30 chests X-rays. Thallium scintigraphy, however, is preferable to exercise ECG alone when the resting ECG shows a non-specific abnormality impairing interpretation of exercise ECG alone or when information on the probable reversibility (or nonreversibility) of apparently infarcted segment is needed to estimate the potential value of revascularization therapy. In the majority of cases of disability evaluation, thallium testing is not necessary in determining the disability status, above and beyond what information that can be derived from a standard exercise test.