Specific Aim #1: To further test the feasibility of the new OBC system for guiding accurate and reproducible breath-hold levels that correlate with internal target position in human volunteers. Hypothesis: The OBC system is as good as or better than the currently used IBC system with regard to accuracy and reproducibility of a reference breath-hold level.~Specific Aim #2: To compare the use of 2 optical-based belts (wrapped around the chest and abdomen) versus 1 optical-based belt (wrapped around the chest or abdomen, depending on which region expands the most during respiration) with regard to accuracy and reproducibility of a pre-determined reference breath-hold level in a subset of patients (prone and/or obese). Hypothesis: The use of 2 optical-based belts allows increased accuracy and reproducibility of a pre-determined reference breath-hold level compared with the use of only one belt in this subset of patients.~Specific Aim #3: To test the clinical feasibility of the new OBC system in patients undergoing CT-guided biopsy of the lung or upper abdomen where respiratory motion is a problem. Hypothesis: The OBC system is as good as or better than the currently used IBC system with regard to the accuracy and reproducibility of the reference breath-hold and ease of use.
The objective or our study is to test the feasibility of a new optical-based breath-hold control (OBC) system for monitoring breath-hold levels and providing patient feedback during CT-guided biopsies of the lung and upper abdomen where respiratory motion is a problem.