What type of radiation does Thallium 201 emit?

Tl-201 emits emitting mainly X-rays of energy 67–82 keV (88% abundance) and gamma photons of 135 and 167 keV (12% abundance). X or gamma rays could not be visible.

What is thallium 201used for?

Thallium-201 is a radiopharmaceutical agent used in the diagnosis of coronary artery disease and parathyroid hyperactivity. Other useful applications for a thallium-201 scan, like tumor diagnosis and olfacto-scintigraphy, are being explored and have shown promising results in various studies.

How is Thallium 201 excreted?

The dosimetry data in Table 4 reflect this distribution pattern and are based on a biological half-life of 2.4 days. Thallous Chloride Tl-201 is excreted slowly and to an equal extent in both feces and urine. Five minutes after intravenous administration only 5 to 8 percent of injected activity remained in the blood.

Is Thallium-201 toxic?

The radioisotope thallium-201 (as the soluble chloride TlCl) is used in small amounts as an agent in a nuclear medicine scan, during one type of nuclear cardiac stress test. Soluble thallium salts (many of which are nearly tasteless) are highly toxic, and they were historically used in rat poisons and insecticides.

What is a NM cardiac myocardial perfusion scan?

Myocardial perfusion is an imaging test. It’s also called a nuclear stress test. It is done to show how well blood flows through the heart muscle. It also shows how well the heart muscle is pumping. For example, after a heart attack, it may be done to find areas of damaged heart muscle.

Who invented thallium-201?

Elliot Lebowitz introduced thallium-201 for myocardial perfusion imaging, first proposed by Kawana.

What is thallium 201 TL?

Thallium-201 ( 201 Tl) is the conventional perfusion tracer [4]. 201 Tl behaves like a potassium analog and enters the myocytes through Na + /K + ATPase channels. 201 Tl is injected intravenously at peak exercise or during pharmacological stress and imaging is started soon after completion of stress.

What is the dose of Tl-201?

• Tl-201 (Thallous Chloride) is supplied in isotonic solution as a sterile, non-pyrogenic diagnostic radiopharmaceutical for intravenous administration. Thallous ions mimic potassium’s biological behavior. • Recommended radiopharmaceutical dose is approximately 1-2 millicuries.

What is Tl-201 used for?

Tl-201 became available in the mid-1970s for myocardial scintigraphy. It behaves as a potassium analog, with high net clearance (~85%) in its passage through the myocardial capillary bed, which makes it an excellent marker of regional blood flow to viable myocardium.

What is the efficacy of Tl-201 in the diagnosis of brain tumors?

201Tl has high uptake in brain tumors46,47 on both early and delayed imaging, which is different from studies obtained from patients with cerebral edema and infection. Harvey A. Ziessman MD, James H. Thrall MD, in Nuclear Medicine (Third Edition), 2006 Tl-201 can successfully differentiate malignant from benign bone lesions.