Designing a New Molecular Probe: The Potential Role for Tilmanocept (Lymphoseek®) in the Assessment of Patients with Painful Hip and Knee Joint Prostheses

摘要

Background:There is a long history of nuclear medicine developments in orthopaedics beginning in the early 20^th century. Technetium-99m (^99mTc) has a short half-life of six hours, emits 140 keV gamma rays and is the most widely used isotope, imaged with the Anger (gamma) camera. Gamma image quality and test sensitivity in painful prosthetic joints can be improved with single photon emission computed tomography (SPECT) and SPECT/CT. Positron Emission Tomography-Computed Tomography (PET-CT) with Sodium Fluoride (¹⁸F-NaF) and ¹⁸Fluorine-fluorodeoxyglucose (¹⁸F-FDG) PET have promising and limited roles respectively in the investigation of painful prosthetic joints. New SPECT/CT and PET-CT isotopes targeting activated macrophages with ^99mTc Tilmanocept (Lymphoseek^®) and ⁶⁸Gallium labelled Tilmanocept respectively show potential as agents to demonstrate wear particles ingested by macrophages and multinucleated giant cells. An imaging algorithm using SPECT and/or PET agents is proffered as a cost effective way of speedily and accurately arriving a diagnosis.