Related Experiment Video
Updated: Jul 13, 2026
09:39
The Trier Social Stress Test Protocol for Inducing Psychological Stress
Published on: October 19, 2011
Tl-201 stress tests and homeland security
Lawrence T Dauer1, Matthew J Williamson, Jean St Germain
1Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA. dauerl@mskcc.org
Summary
Patients may trigger radiation detectors for up to 51 days after thallium-201 (Tl-201) cardiac imaging, necessitating patient advisories. This is significantly longer than after technetium-99m myocardial imaging.
Area of Science:
- Nuclear Medicine
- Radiopharmacology
- Security Technology
Background:
- Increasing use of thallium-201 (Tl-201) for cardiac imaging.
- Deployment of sensitive radiation detection devices by the US Department of Homeland Security.
- Potential for patients undergoing nuclear medicine procedures to trigger security alarms.
Purpose of the Study:
- To estimate the duration patients may trigger security radiation detection devices after Tl-201 cardiac imaging.
- To inform security protocols and patient advisories regarding post-imaging radiation detection.
Main Methods:
- Estimation based on Tl-201 radiopharmacokinetics and radioactive contaminants.
- Consideration of current radiation detection device sensitivity.
- Modeling of radioactive source distribution and attenuation within the patient.
Main Results:
- Patients may trigger portable pager devices for up to 33 days post-Tl-201 imaging.
- Patients may trigger portal detectors for up to 51 days post-Tl-201 imaging.
- This duration is substantially longer than the up to 6 days for technetium-99m myocardial imaging.
Conclusions:
- Standard practice should include issuing information cards to patients.
- Cards should detail the potential time for triggering security radiation detectors after Tl-201 procedures.
- Advisories are crucial for diagnostic cardiac procedures involving Tl-201 or other radiopharmaceuticals.
Related Concept Videos
01:26Exercise Stress Test
Introduction
Exercise stress testing, commonly known as a treadmill test, is a noninvasive procedure used to evaluate cardiovascular function and diagnose heart conditions.
Definition
An exercise stress test measures the heart's response to exertion using a treadmill or stationary bicycle. Chest electrodes record the heart's electrical activity through an ECG, and blood pressure is monitored regularly.
Purposes
Exercise stress testing, commonly known as a treadmill test, is a noninvasive procedure used to evaluate cardiovascular function and diagnose heart conditions.
Definition
An exercise stress test measures the heart's response to exertion using a treadmill or stationary bicycle. Chest electrodes record the heart's electrical activity through an ECG, and blood pressure is monitored regularly.
Purposes
01:27Introduction to Stress and Lifestyle
Stress is a multifaceted response to events perceived as challenging or threatening, highlighting physical, emotional, cognitive, and behavioral reactions. Physically, stress can lead to fatigue, sleep disruptions, and various health issues such as frequent colds, chest pains, and nausea. Emotionally, it can manifest as anxiety, depression, irritability, and anger triggered by both minor and major life events. Cognitively, it may result in difficulty in concentration, memory, and...
01:24Stress Concentrations
Stress concentration is when stress intensifies near discontinuities such as holes or abrupt cross-sectional changes in a structural member. This localized stress can often surpass the average stress within the member. The stress distribution in flat bars, either with a circular hole or varying widths connected by fillets, can be determined experimentally using a photoelastic method. The results are based on ratios of geometric parameters like the ratio of the hole's radius to the smaller width...
01:13Stress Concentrations
The concept of stress concentration is crucial for understanding how materials respond under bending stresses, particularly when there are irregularities or discontinuities in the material's geometry. Normally, stress in a symmetric member subjected to pure bending is assumed to be uniformly distributed across the entire cross-section. However, this assumption does not hold when there are variations in the cross-sectional geometry or the presence of notches and holes.
The stress concentration...
The stress concentration...
01:21General State of Stress
The general state of stress within a material can be accurately depicted using a stress tensor. This tensor encapsulates the internal forces distributed within a material subjected to external forces or deformations.
Specifically, consider a tetrahedral element where one face, labeled XYZ, is perpendicular to the line OA, and the remaining faces align with the coordinate axes with point O as the origin. At any point, such as point O, the stress tensor can be used to determine the stress...
Specifically, consider a tetrahedral element where one face, labeled XYZ, is perpendicular to the line OA, and the remaining faces align with the coordinate axes with point O as the origin. At any point, such as point O, the stress tensor can be used to determine the stress...
01:21Stress Response System
The stress response system, also known as the fight-or-flight response, is the body's automatic physiological reaction to perceived threats. Hans Selye introduced the concept of General Adaptation Syndrome (GAS) to describe the predictable pattern of changes that occur in response to stress. GAS consists of three sequential stages: alarm, resistance, and exhaustion. This model helps explain how chronic stress can contribute to health problems.
Alarm stage
In the alarm stage, the body's initial...
Alarm stage
In the alarm stage, the body's initial...