ICG-based fluorescence imaging to assess muscle perfusion for guiding surgical debridement after acute compartment syndrome.

Abstract

Acute Compartment Syndrome (ACS) is a severe condition that can threaten limb viability, particularly in patients who experience prolonged immobility, such as in the found-down phenomenon. Inadequate removal of nonviable muscle after fasciotomy increases the risk of infection. While non-invasive imaging modalities have been explored for early ACS diagnosis, no tools currently exist to guide precise debridement intraoperatively. Existing technologies are limited by susceptibility to interference, lack of standardized thresholds and insufficient real-time surgical utility. This study aimed to evaluate the association between muscle perfusion, quantified by indocyanine green (ICG)-based dynamic contrast-enhanced fluorescence imaging (DCE-FI), and the degree of muscle necrosis in ACS, assessed via histopathological analysis, to explore the potential of DCE-FI to guide intraoperative muscle debridement. A total of 15 adults (aged 18 years or older) undergoing ACS surgical treatment were included in this study between 2023 and 2024. DCE-FI imaging was performed and eight muscle specimens spanning the entire length of the incision were obtained for each patient. Necrosis percentage was assigned to each sample based on histopathological evaluation by a pathologist. Patients were then classified into high necrosis (HN) and low necrosis (LN) groups based on their average necrosis scores from these eight samples, using 50 % necrosis as a cutoff. Perfusion-related kinetic parameters derived from DCE-FI, including maximum fluorescence intensity (I_max) and blood flow (BF), were evaluated and compared between the two groups. The HN group exhibited significantly lower I_max (p < 0.001) and BF (p < 0.001), compared to those in the LN group, indicating substantially reduced muscle perfusion. The HN group had significantly lower median values (I_max 23.0 RFUs, BF 1.9 mL/min/100g) compared to the LN group (I_max 32.4 RFUs, BF 3.1 mL/min/100g). ICG-based DCE-FI demonstrated strong potential for intraoperative identification of muscle damage resulting from ACS. This technique may serve as a valuable adjunct for guiding surgical debridement which may minimize complications and reduce the number of debridement procedures required, particularly in challenging cases of delayed or missed diagnosis of compartment syndrome.