The Use of Quantitative SPECT/CT Imaging to Assess Residual Limb Health

Service members from recent conflicts are suffering traumatic injuries that result in limb amputations at an increased rate compared to previous conflicts. Thus, tremendous efforts have been made in recent years at improving prosthetic devices. The socket is a critical feature of a prosthetic device as it acts as the interface between the prosthesis and residual limb. Numerous residual limb health issues have been associated with traditional socket technologies. The health of residual limb tissue in persons with lower-limb amputation is of critical importance. Breakdown of tissue viability of the residual limb can negatively impact the progress of the patient's rehabilitation and/or lead to prosthesis abandonment, thus reducing their mobility, function, and overall quality of life. New socket technologies are being developed to aid in the maintenance of tissue health in the residual limb. However, limited technologies are available to assess the impact of these sockets on the health of the residual limb. A non-invasive, sensitive, and quantitative imaging modality that could provide an objective assessment of the overall health of the residual limb would advance the standard of care for affected patients. Radiotracer-based imaging with single photon emission tomography (SPECT)/X-ray computed tomography (CT) (SPECT/CT) can provide a quantitative assessment of bulk tissue perfusion within three-dimensional regions of interest under resting or stress conditions. The main objectives of the current research proposal are to assess the utility of SPECT/CT perfusion imaging for evaluation of patients with lower extremity amputation and to assess the effectiveness of SPECT/CT imaging in determining the impact of new socket technologies on the health of the residual limb. Completion of the proposed study could greatly benefit patient care by providing a highly sensitive, non-invasive tool for clinicians and researchers to use for assessment of tissue health in the residual limb of patients with lower extremity amputations, both in the acute setting following surgical intervention and chronically, to evaluate next-generation prosthetic socket technologies. This 2-year pilot study will provide important preliminary data to assess the utility of non-invasive quantitative imaging as a means to evaluate residual limb health. This type of evidence-based research is becoming critical for insurance companies to pay for higher priced devices that may provide greater benefits to patients. As such, results from the proposed study could significantly reduce cost and burden to the Department of Defense and Department of Veterans Affairs systems by providing justification towards the prescription of prosthetic socket technologies that are most effective at promoting the overall health/tissue viability of the residual limb.