Comparing Xperguide vs. Conventional Methods During Percutaneous Image Guided Procedures

Background: \- Procedures that use medical tools in or near a possible abnormality in the body often use computed tomography (CT) scans to locate the abnormality and guide the path that a needle will take to collect a sample of tissue. Xperguide and electromagnetic (EM) tracking are two new procedures being studied to help guide the needle. Xperguide is software that uses CT images to help the doctor choose the needle path. EM tracking uses special medical tools with miniature coils that act like a Global Positioning Satellite (GPS) device to show the location of the needle in the body. Xperguide and EM tracking have been used in humans and have good results, but they have not been compared with each other and regular CT to determine whether they are better than the standard approach. Objectives: \- To compare the results of Xperguide, electromagnetic tracking, and regular computed tomography during a guided percutaneous procedure. Eligibility: \- Individuals at least 18 years of age who are required to have a CT-guided percutaneous procedure. Design: * Participants will be screened with a physical examination and medical history, and the results of any previous imaging studies will be examined before study enrollment. * After a pilot phase, the study will involve two phases to compare the results of the different procedures. The first phase will involve comparing Xperguide to CT, and the second will involve comparing Xperguide to EM tracking. * Phase 1 participants will be assigned to one of two procedure groups: Group 1 will have Xperguide, and Group 2 will have regular CT. Participants who are scheduled to have repeated procedures (like a biopsy before and after chemotherapy) will be randomized for the first procedure and the second procedure will be done using the other method. * Phase 2 participants will be assigned to one of two procedure groups: Group 1 will have Xperguide, and Group 2 will have EM tracking. Participants who are scheduled to have repea