Dynamic Susceptibility Contrast Perfusion, Part 1: The Fundamentals

Area of Science:

• Physiology
• Medicine
• Biomedical Engineering

Background:

• Accurate measurement of blood flow is vital in medicine and physiology.
• Initial focus was on organ-level blood flow, but shifted to capillary blood flow for local tissue nutrient delivery.
• Early methods involved gases and microspheres, but faced practical challenges.

Purpose of the Study:

• To highlight the evolution of blood flow measurement techniques.
• To emphasize the shift towards capillary blood flow assessment.
• To explain the prevalence of indicator dilution methods.

Main Methods:

• Discusses the historical development of blood flow measurement techniques.
• Compares early methods (gases, microspheres) with current approaches.
• Focuses on the principles of indicator dilution.

Main Results:

• Indicator dilution has emerged as the most practical and prevalent method.
• Microsphere-based methods are less practical for widespread use.
• Capillary blood flow measurement is key for understanding local tissue perfusion.

Conclusions:

• Indicator dilution is the current standard for measuring capillary blood flow.
• The impracticality of older methods drove the adoption of indicator dilution.
• Understanding capillary blood flow remains a critical area in physiological research.