ICG Fluorescence Imaging in Post-traumatic Infection

The focus of this prospective observational study is to (1) establish the range and variation associated with bone/soft tissue perfusion in fracture patients, using ICG fluorescence imaging; (2) examine the relationship between perfusion and complications such as surgical site infection (SSI), persistent SSI, and fracture nonunion; (3) to determine whether the quantitative ICG fluorescence can be used to guide bony debridement in the setting of infected fracture to minimize complications.

This will be a prospective observational trial to better understand the range and variation associated with bone/soft tissue perfusion in fracture patients and examine the relationship between perfusion, measured using quantitative Indocyanine green (ICG) fluorescence and complications such as surgical site infection (SSI), persistent SSI, and fracture nonunion. Primary outcome measure is complication (either infection, recurrent infection or nonunion).

Eligible consenting patients will receive standard of care treatment for their fracture or infection including irrigation and debridement of their operative site and/or fracture fixation. After exposure, 0.1 mg/Kg ICG will be injected intravenously and video rate ICG fluorescence images will be acquired 20 seconds before and 4 minutes after the injection, each before and after debridement.

A subset of 30 post-fracture complication patients will undergo surgical treatment for their infection in Center of Innovation Surgery (CIS) and have either an intraoperative Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) after exposure but before the ICG injection or a preoperative DCE-MRI. Patients receiving surgery in the CIS will be required to sign an additional CIS-specific consent document.

The need for repeat surgical procedure will be left up to the treating surgeon. If repeat procedure is needed, pre- and post-debridement quantitative ICG fluorescence images will be obtained at each procedure.

Study participants will be followed at 2 weeks, 6 weeks, 3 months, 6 months, and one year from their index study surgery. Complication including index infection, recurrent infection or delaying union/nonunion will be identified at the time of diagnosis and/or during each participants assessment that occurs during routine outpatient clinic visit. Detailed information on the infection including date of diagnosis, participant signs and symptoms, culture test results, method of treatment(s), and date of resolution will be documented.