The lack of rigidity in the loosely overlaid structure of the organs in the peritoneal cavity makes it difficult to identify normal organ structure and position by sonography in a micro-gravity environment. The nature of sonographic imaging, an extremely difficult skill that relies on the ability to identify landmarks in the body to locate structures, exacerbates the problem. NASA has used ultrasound imaging previously on the KC-135 Reduced Gravity Flight and in space. Early experiments were confounded by, and in some cases, failed because of the movement of an astronaut?s organs in space [Wayne Sternberger Ph.D., John Hopkins Univ. APL, Jan 24, 2000] [Steve Carter M.D., Dept. of Radiology, University of Washington, personal communication, Feb 27, 2000]. The Applied Physics Laboratory (APL) of the University of Washington has undertaken an extensive effort to develop technology that would permit minimally trained personnel to utilize diagnostic and therapeutic ultrasound to terminate both external and internal bleeding, ultimately to be used in space [Lawrence Crum, NSBRI proposal]. Such a procedure is complicated by the phenomenon of micro-gravity induced organ shift. NASA owns two SonoSite 180 handheld ultrasound-imaging units [Steve Carter M.D., Dept. of Radiology, University of Washington, personal communication, Feb 24, 2000], which is the same instrument this flight team will use.

The objectives of this project are two-fold. First, the flight team will measure organ displacement using ultrasound. In these measurements, taken at 0-, 1- and 2-Gs of acceleration, the locations of specific landmarks will be identified in three dimensions from the collected data. By taking repeated measurements of organ position as a result of different gravitational environments and comparing the images, this project will characterize organ shift patterns for the kidney, and thereby increase the predictability of organ location for future endeavors with ultrasound in micro-gravity environments. Additionally, by collecting ultrasound data at specific values of gravitational forces, we hope to identify problems that have not yet been anticipated so that future missions involving ultrasound can be better prepared for space flight. Our second objective is to provide an outreach program. By visiting local schools, publishing a web site, evoking local media coverage, and presenting our findings at a scientific conference, we will reach out to a broad spectrum of people, thus providing positive publicity for NASA, APL, and the UW.