Back pain and injury are recognized risks that can affect the well-being and performance of crewmembers during missions, as well as their long-term health. Spine elongation is a documented effect of microgravity, back pain is a common occurrence in early flight, and the post-flight incidence of spinal injury is higher than the population average. These observations suggest that spinal unloading results in a transition to a new set point for the spine, and causes discomfort and an increased risk of injury.

Due to the lack of appropriate technology and methodology, in-flight spinal changes have been studied only with stadiometry. MRI is currently considered the gold standard for spinal imaging, but the only imaging modality available on the International Space Station (ISS) is ultrasound. To explore the possibility of using ultrasound for spinal imaging, a groundbased phase feasibility testing was previously conducted to demonstrate the ability to correlate spinal MRI and ultrasound imagery. The subsequent spaceflight phase of the study is directed at refining this methodology and expanding its use to address questions about spinal changes induced by spaceflight. This study compares pre-, in-, and post-flight ultrasound images of the cervical and lumbar spine to the respective MRI data.

Intervertebral disk (IVD) measurements and mutual positions of the vertebrae will be included in the analysis to characterize the microgravity-induced changes to the spine during the course of a mission. In-flight, crewmembers will use experiment- unique multimedia software that is designed to enhance image reproducibility through just-in-time review of the experiment protocol and specific techniques for each segment of the spinal column.

Experiment-specific software is initially used as part of preflight training to enhance understanding of the proper imaging technique and associated imagery as well as to reduce training time. This software is then used just prior to each on-orbit imaging session to review the spinal ultrasound technique using animations, imaging tips, target imagery, and equipment settings. In place of a step-by-step scanning procedure, the crewmember operators use intuitive software to prepare for the procedure, which is then conducted with real-time guidance from the Telescience Center at NASA JSC.

This software is Flash-based, and is the fourth release of this type of training tool by members of NASA and these investigators. The original tool was released in 2004 aboard ISS as a bilingual (Russian and English) multimedia interactive program called OPE (On-orbit Proficiency Enhancement). It was used primarily to familiarize the operators with the hardware setup, anatomy of the patient, principles of ultrasound, and remote guidance techniques. Included in OPE was a series of games to prepare the novice ultrasound operators in a selfpaced and entertaining virtual environment. At any time during the OPE session, the operator could switch languages. To aid in education and future training material development, all OPE keystrokes, menu selections, and language choices were recorded and retrospectively analyzed to correlate software use details with operator experience during the subsequent imaging session.

This release takes advantage of the enhanced features of the Second Generation ISS Ultrasound, including the keyboard overlay. This “guidance-optimized” keyboard concept was largely influenced by previous versions of this software and is used now in real-time remote guidance universally across all experiments and medical uses of the ultrasound system on ISS. Additionally, the OPE software and just-intime training and refresher tools were adapted for use at all American Olympic training facilities in both Summer and Winter Games. The second and third iterations of the multimedia training software were not manifested on the ISS, but were used throughout the world in training more advanced remotely guided ultrasound activities, and furthered the efforts to bring enhanced ultrasound capabilities to remote settings. These products and techniques are critical components of bringing medical care to parts of the world that do not have advanced imaging equipment and highly trained personnel at each site of care. Without access to technology such as X-ray Computed Tomography (CT) or MRI, for the time being ultrasound will remain the only feasible general diagnostic imaging modality.

This work was done by Scott Dulchavsky of Henry Ford Hospital; and Douglas Ebert, Kathleen Garcia, Ashot Sargsyan, and Vicky Byrne of Wyle Laboratories for Johnson Space Center. MSC-25501-1

Photonics & Imaging Technology Magazine

This article first appeared in the January, 2016 issue of Photonics & Imaging Technology Magazine.

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