Related Experiment Video
Updated: Sep 26, 2025

Quantifying Single Microvessel Permeability in Isolated Blood-perfused Rat Lung Preparation
Published on: June 30, 2014
Pulmonary perfusion imaging and delayed imaging to measure pulmonary capillary permeability in pulmonary contusion
Kai Xiong1, Shicong Li1, Yao Yu1
1Cardiovascular Thoracic Surgery.
Purpose:
Explore the application value of pulmonary perfusion imaging and delayed imaging for evaluating pulmonary capillary permeability.
Materials And Methods:
After establishing a rat model of pulmonary contusion, changes in the metabolic index of technetium-99m macroaggregated albumin (99mTC-MAA) in the lungs of model rats were evaluated for two consecutive days. 99mTC-MAA metabolic indices of rat lungs with pulmonary contusion of varying severity (mild, moderate, and severe) were correlated with lung wet/dry weight ratio (W/D) and Evans blue extravasation. Finally, the method was validated in patients with pulmonary contusion and one healthy volunteer.
Results:
The 99mTC-MAA metabolic index was 23.56% ± 2.44% in healthy control (HC) rat lung, 8.56% ± 3.42% immediately after lung contusion (d0), 8.35% ± 3.20% after 1 day (d1), and 17.45% ± 6.44% after 2 days (d2); indices at d0 and d1 were significantly higher than those at HC (P < 0.05). The metabolic index of 99mTC-MAA in lung had significant negative correlations with W/D (r = -0.8025; P = 0.0092) and Evans blue extravasation (r = -0.9356; P = 0.0002). Metabolic and oxygenation indices of 99mTC-MAA exhibited a significant positive linear correlation in patients with pulmonary contusion (r = 0.8925; P = 0.0416).
Conclusion:
Pulmonary perfusion and delayed imaging of 99mTC-MAA have potential value for evaluating pulmonary capillary permeability.
Related Concept Videos
Pulmonary Embolism II: Diagnostic Studies and Interprofessional Care
Radiological Investigation III: Pulmonary Angiogram and PET Scan
Pulmonary Angiogram
A Pulmonary Angiogram is an invasive procedure involving injecting a contrast medium through a catheter threaded into the pulmonary artery or the right side of the heart to visualize the pulmonary vasculature. Computed Tomography (CT) scans have mainly replaced this...
Radiological Investigation II: MRI and Ventilation Perfusion Scan
Magnetic Resonance Imaging (MRI) and Ventilation Perfusion Scans are two radiological investigations that offer detailed diagnostic images of the body, particularly lung structures.
MRI
MRI uses magnetic fields and radiofrequency signals to distinguish between normal and abnormal tissues. This technology provides a more detailed diagnostic image than CT scans, enabling it to characterize pulmonary nodules, stage bronchogenic carcinoma, and evaluate inflammatory activity in...
Assessment of Diffusion and Perfusion
The Role of Diffusion in Respiration
Diffusion is the process by which molecules move from an area of higher concentration to an area of lower concentration. In the respiratory system, this...

