Pulmonary function-morphologic relationships assessed by SPECT-CT fusion images

Area of Science:

• Radiology
• Pulmonary Medicine
• Medical Imaging

Background:

• Pulmonary SPECT-CT fusion imaging enhances the assessment of lung function and morphology.
• Understanding lung pathophysiology in diverse disorders is crucial for diagnosis and management.

Purpose of the Study:

• To review significant findings in lung pathophysiology across various disorders using SPECT-CT fusion images.
• To highlight the utility of SPECT-CT in correlating lung function with CT morphology.

Main Methods:

• Review of 8 years of experience with pulmonary SPECT-CT fusion imaging.
• Analysis of SPECT-CT findings in conditions like pulmonary thromboembolism, COPD, interstitial lung diseases, and hepatopulmonary syndrome.

Main Results:

• SPECT-CT confirmed low CT attenuation mechanisms related to hypoxic vasoconstriction and pulmonary arterial obstruction.
• Lung perfusion distribution correlated better with CT attenuation than ventilation in mosaic attenuation.
• SPECT-CT identified perfusion defects beyond CT findings in COPD and ILD, and revealed 'steal phenomenon' in hepatopulmonary syndrome.

Conclusions:

• Pulmonary SPECT-CT fusion imaging provides a comprehensive understanding of lung pathophysiology.
• It demonstrates superior sensitivity for detecting subtle lung lesions compared to CT alone in certain conditions.
• This imaging modality is valuable for assessing the functional impact of vascular abnormalities on lung perfusion.