[CT measurement of the thoracic density]

Area of Science:

• Radiology
• Pulmonary Medicine
• Medical Imaging

Background:

• Lung density assessment is crucial for estimating ventilation capacity.
• Lung parenchyma is heterogeneous, requiring precise CT number measurement of normal tissue.
• Accurate CT values are needed for reliable pulmonary function estimation.

Purpose of the Study:

• To establish normal lung density using computed tomography (CT) of the chest.
• To determine if CT numbers can quantify effective ventilation capacity.
• To analyze variations in lung density across different thoracic regions.

Main Methods:

• Assessed mean CT values in 34 patients (including those with lung disease and healthy controls).
• Measured density of normal peripheral lung tissue at 6 points per slice using a GE9800 CT scanner.
• Utilized regions of interest (0.01 cm²) for precise CT number calculation.

Main Results:

• No significant difference in lung density was found between the left and right lungs.
• Lung density showed no significant variation among different CT slices.
• A significant difference in lung density was observed between anterior and posterior regions.

Conclusions:

• Normal lung density can be established using CT imaging.
• CT numbers provide a basis for estimating lung ventilation capacity.
• Understanding lung density variations is key for accurate pulmonary function assessment.