Body Composition/Bone Density Facility
The Body Composition/Bone Density Facility provides access to state-of-the-art methods for measuring body composition and bone density in humans. Under the direction of Michael Jensen, M.D., the facility's staff offer Mayo researchers advice and assistance in the use of body composition/bone density techniques to address relevant experimental questions. The services and equipment chosen for this facility are those that are currently heavily utilized by Mayo investigators.
The facility serves any researcher in need of human body composition or bone mineral density data. We have worked with investigators studying metabolic, cardiovascular, respiratory, muscle and bone-related diseases, and are eager to help those in other areas of research.
Consolidating body composition and bone density measurement technology into one shared facility benefits Mayo investigators, as it provides an area with concentrated expertise to assist in study design and interpretation. The consolidation also allows for longitudinal quality control, which permits stable measurements over decades despite changes in equipment or software versions.
Services and equipment
Dual energy X-ray absorptiometry (DEXA)
The GE Lunar iDEXA whole body scanner — incorporates significant design changes over the facility's previous densitometer:
- Spatial resolution of the detectors has been improved by a factor of two, enhancing image quality and thereby leading to better definition and detection of bone edges. Improved detection of bone edges allows the software algorithms to calculate bone density with improved precision and accuracy.
- Use of a scalable x-ray energy (adjustable up to a factor of three) and the strengthening of the patient table. These two changes are important as they now allow, for the first time, evaluation of obese subjects up to 450 pounds.
Measuring visceral fat by computed tomography (CT) scanning
The facility coordinates access for clinical and translational investigators to measurements of visceral and subcutaneous abdominal adipose tissue content via the Mayo Clinic Department of Radiology. Single-slice CT images of the abdomen at the L2 (vertebra) interspace level are provided for a fee. The scans are performed with a Siemens Sensations 64 CT slice; the images can be analyzed using TomoVsion sliceOmatic software or an in-house program developed in the Department of Radiology (RIL-Contour) that has machine learning features that reduce the time needed to analyze images.
HR-pQCT (Xtreme CTII)
High resolution images of the distal radius and distal tibia are obtained using the Scanco HR-pQCT device (Xtreme CTII). This second-generation device allows for noninvasive assessment of bone microstructure.
Accessing the facility
Approval from both the Mayo Clinic Institutional Review Board (IRB) and the Radiation Safety Committee is required before an investigator may use the Body Composition/Bone Density Facility. Requests for use are initiated through completion of the Clinical Research and Trials Unit (CRTU) section of the IRBe application.
During the protocol development process, Body Composition/Bone Density Facility staff can assist with study design and advise which facility resources would best suit the needs of a particular study. During the study, technical support is provided by staff with limited radiography certification. Upon completion of the study, scan results are given to the investigational team.
Location and hours
A Lunar iDEXA is located in the Body Composition/Bone Density Facility on Joseph 5, Saint Marys CRTU and the Charlton CRTU and the Xtreme CT II are also located in the Charlton CRTU. Other CT instruments used are in Mayo Clinic Hospital, Saint Marys Campus, one floor above the Body Composition/Bone Density Facility.
Facility hours are Monday-Friday from 7 a.m. to 4 p.m. Studies requiring measurements outside these times require investigative teams to work directly with facility staff to determine coverage of involved measurements.