What are the three types of stress tests? The three basic types are exercise, pharmacologic vasodilatory, and adrenergic agonist stress tests. • Exercise stress tests are typically performed using a treadmill with several possible protocols that sequentially increase the speed and grade of the treadmill. An alternative exercise test uses a stationary bicycle. The goal is to …
What are the different types of radiotracers available for stress testing? There are three basic categories: thallium-201 ( 201 Tl) and technetium-99m ( 99m Tc)-labeled compounds for SPECT, and positron emitting compounds for PET. The below table compares 201 Tl and 99m Tc-labeled compounds. The most commonly used 99m Tc-labeled compounds are tetrofosmin and sestamibi, which have similar imaging and chemical characteristics. 99m Tc-labeled compounds generally provide …
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How to prepare for stress myocardial perfusion imaging (SMPI)? Patients should be informed that the test takes approximately one half day and consists of two parts: a resting part and a stress part. The placement of an intravenous catheter (usually inserted at the beginning of the study) is required to administer the radiotracer. The order …
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What is a pentetreotide scan and what is it used for? A pentetreotide scan (sometimes referred to as an octreotide scan or an OctreoScan™, utilizes the radiotracer indium-111 ( 111 In) pentetreotide, which binds to neuroendocrine tumors that express somatostatin receptors. Typically, patients are injected on the first day and imaged at 24 hours post injection. The …
Nuclear medicine scans to detect a pheochromocytoma What are some available nuclear medicine scans that can be used to detect a pheochromocytoma? There are several radiotracers that can be used for detection of a pheochromocytoma. The pentetreotide scan mentioned above is useful for detecting pheochromocytomas. However, two related radiotracers, iodine-131 ( 131 I) metaiodobenzylguanidine (MIBG) and iodine-123 …
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What physiologic factors normally affect gastric emptying? Numerous factors can affect gastric emptying. Factors that increase the gastric emptying rate include upright patient positioning, younger age with male gender, higher liquid content of food, smaller size of food particles, larger volume of food, and lower fat content of food. Factors that can slow the rate …
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How does a gastric emptying study work? A gastric emptying study involves the ingestion of a standardized meal consisting of some food source that is tagged with a radioactive label. The most common meal utilized for the study consists of egg whites tagged with 99m Tc sulfur colloid. Meals must be standardized for content and calories so …