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A century of indicator dilution technique
Jens H Henriksen1, Gorm B Jensen, Henrik B W Larsson
1Department of Clinical Physiology and Nuclear Medicine 239, Center of Functional and Diagnostic Imaging and Research, Hvidovre Hospital, Faculty of Health Sciences, University of Copenhagen, Hvidovre, Denmark.
Clinical Physiology and Functional Imaging
|July 23, 2013
Summary
The indicator dilution technique, a century-old method, continues to evolve. Modern advancements integrate this flow measurement technique into advanced imaging like SPECT, PET, and MRI.
Area of Science:
- Physiology
- Medical Imaging
- Biomedical Engineering
Background:
- The indicator dilution technique, originating 100 years ago, measures flow using injected substances.
- Its application expanded significantly with intravascular dyes in 1928.
- Key developments include multiple indicators, radioactive tracers, and advanced detection methods from the 1950s-1960s.
Observation:
- Clinical applications broadened in the 1970s for organ systems like the heart, brain, lungs, liver, and kidneys.
- Powerful computing in the 1980s-1990s significantly enhanced the technique's capabilities.
- The technique remains fundamental, forming the basis for modern imaging modalities.
Findings:
- The indicator dilution technique has a rich history spanning a century.
- It has continuously adapted, integrating new technologies and indicators.
- Current applications range from traditional flow measurement to advanced quantitative imaging.
Implications:
- This technique's foundational principles are integral to contemporary medical diagnostics.
- It underpins quantitative SPECT, positron emission tomography, and dynamic MRI.
- Ongoing refinements suggest substantial future potential for this enduring concept.
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