Chronic pain is a debilitating disease, which affects approximately 1.5 billion people worldwide, and of those, approximately 4% suffer from neuropathic pain. Neuropathic pain is often described as a shooting or burning pain that can come and then disappear but equally it may become chronic, where the pain may become unrelenting and severe. It often is the result of nerve damage or a malfunctioning nervous system. Additionally there is the impact upon society where the costs related to disability allowance, treatment, lost wages and productivity impacts the economy. Current treatments for chronic pain are not fully reliable and there is a severe lack of tools to diagnose or visualise the pain process within the dorsal root ganglia (DRG). Humans have 62 DRGs which are the first relay stations in the pain pathway. Local targeted treatment at the level of those DRGs involved in the pain process is the solution to circumvent side effects and optimise treatment. 

We aim to identify involved DRGs by visualising cells or molecules in the DRG which are directly or indirectly associated with the generation of pain. We will use a novel method of nanoparticles targeted towards pain-associated cells or molecules in the DRG. A vast amount of neuropathic pain studies have shown an eminent infiltration of macrophages into affected DRGs. These nanoparticles will be specifically designed to target initially the macrophages in the DRG, encapsulating both therapeutic payloads and imaging contrast reagents to monitor pain-associated activities. The goal of PIANO is therefore to facilitate a state-of-art approach to visualisation of neuropathic pain / inflammation at DRG sites as well as to simultaneously release analgesic molecules from the nanoparticles.