The basic high resolution CT scan is the next-preferred CT scan for collecting LTRC scan data from patients enrolled in this study.

The basic high resolution CT scan protocol will include high-resolution images of the lungs (approximately 1.0 mm) obtained at 10mm intervals acquired in full inspiration. These images will be acquired as single axial scans or groups of scans each of which will require the participant to hold his/her breathe less than a 15 second breath-hold.

The specific acquisition parameters, including high spatial frequency reconstruction algorithms mAs and kVp settings will be tailored for each scanner available at the Clinical Centers.

The maximum effective dosage delivery for this LTRC CT scan will be no more than 5 mSv. These images will be sent to the RCL for analysis and storage.