Tomographic digital subtraction angiography for lung perfusion estimation in rodents

Area of Science:

• Biomedical Imaging
• Medical Physics
• Small Animal Research

Background:

• In vivo perfusion measurement in small animals is challenging due to resolution requirements.
• Existing techniques like MRI, microCT, and microPET have limitations in spatial and temporal resolution for perfusion studies.
• Accurate perfusion imaging is crucial for understanding disease models and therapeutic responses.

Purpose of the Study:

• To demonstrate the utility of tomographic digital subtraction angiography (TDSA) for estimating small animal perfusion.
• To establish the capabilities of TDSA in small animal lung perfusion studies.
• To optimize TDSA imaging parameters for a balance between resolution, contrast, and artifact reduction.

Main Methods:

• Developed and utilized an in-house imaging system for four-dimensional (4D) imaging.
• Employed tomosynthesis algorithms to reconstruct 3D spatial information from 2D DSA projections.
• Acquired data with high temporal resolution (140 ms) and in-plane spatial resolution (100 microm).
• Optimized TDSA parameters including slice thickness, contrast injections, and noise reduction.

Main Results:

• Successfully applied TDSA for in vivo perfusion estimation in rat lung models.
• Achieved high-resolution 4D imaging data suitable for parametric perfusion mapping.
• Demonstrated a trade-off optimization for TDSA imaging parameters.
• Generated parametric maps of perfusion using both DSA and TDSA.

Conclusions:

• TDSA is a promising technique for accurate in vivo perfusion measurement in small animals.
• The method offers high spatial and temporal resolution, surpassing limitations of conventional imaging modalities.
• TDSA has significant potential for advancing research in animal models of disease and evaluating therapeutic efficacy.