Objective:

To evaluate the agreement of key Q-ICG-FA parameters across two independent software platforms using identical ICG-FA recordings.

Approach:

• Study Design: Retrospective comparative analysis of 80 ICG-FA recordings from reconstructive procedures using two software platforms: AMS and EPA.
• Data Analysis: Fluorescence-time curves (FTCs) were generated, and seven perfusion parameters were calculated. Agreement was assessed using intraclass correlation coefficients (ICC), non-parametric testing, and Bland–Altman analysis.

Key Findings:

• Excellent agreement for time-to-peak (TTP) with ICC = 0.979 (95% CI: 0.967–0.987).
• Normalized mean slope inflow showed good agreement with ICC = 0.944 (95% CI: 0.913–0.964).
• Poor to moderate agreement for normalized maximum slopes with ICC values of 0.412 for inflow and 0.315 for outflow.
• Significant systematic differences for six out of seven parameters, with AMS showing higher TTP values than EPA (p < 0.001).
• Normalized mean slope inflow demonstrated the least variability and best agreement across platforms.

Interpretation:

TTP and normalized mean slope inflow may be reliable candidates for defining quantitative perfusion thresholds, although further clinical validation is needed.

Limitations:

• Study limited to two software platforms and a single cohort of patients.
• Potential variability in imaging protocols and analysis methods not fully addressed.

Conclusion:

Further clinical validation is necessary to establish reliable perfusion thresholds based on Q-ICG-FA parameters.