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My Canadian Pharmacy: Use of CT Morphometry To Detect Changes in Lung Weight and Gas Volume

Chronic lung diseasesDuring the last decade, investigators have begun to quantify the amount of disease in patients with chronic lung diseases, including emphysema and interstitial lung disease. This quantification is based on the fact that the changes in lung structure caused by progression of the disease produce changes in lung density, which is linearly related to the attenuation of x-rays. This has been best shown for emphysematous destruction of the lung where the decrease in tissue and increase in gas volume lowers lung density, but it also occurs in end-stage interstitial lung disease, where the decrease in the volume of gas in the tissue raises lung density. Because of the spatial information contained with the CT image, CT scans can be used to measure the total volume of the lung. The combination of lung volume and density makes it possible to estimate other volumetric parameters such as lung weight and gas volume. We refer to the collection of techniques used to quantify lung structure using CT as CT morphometry (CTM).

The present study was designed to test the hypothesis that CTM can be used to track the changes in lung density in diffuse lung disease. Pulmonary alveolar proteinosis (PAP) was used as a model of diffuse lung disease because there is significant improvement, and in some instances almost complete resolution, of the infiltrate following an intervention with the unique opportunity that the dry weight of the material removed from the lung can be measured and compared to the change in CT measured lung weight from before to after lavage. People undergo so many medical screenings to be sure they are safe and sound but if you come across with problems you are welcome on My Canadian Pharmacy.