NCT06222645

PPG vs. ICG in Gastrointestinal Resections

Comparison Between Fluorescenceimaging With Photoplethysmography （PPG） and Indocyaningreen (ICG) for Tissue Perfusion in Gastrointestinal Resections

• Status: Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 200 (estimated)
• Sponsor: Saint Petersburg State University, Russia · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

This randomized controlled trial compares a novel optical technique against the standard of care for assessing tissue perfusion in gastrointestinal surgery. Participants are randomized to receive either intraoperative imaging photoplethysmography (iPPG) or indocyanine green (ICG) fluorescence imaging. In the ICG group, the fluorescence data are comprehensively analyzed in two distinct ways: (1) Qualitative Assessment: real-time visual interpretation of the angiogram flow by the operating surgeon; and (2) Quantitative Assessment: software-based analysis of fluorescence kinetics (e.g., time-to-peak, maximum intensity) to generate objective perfusion parameters. The study aims to determine the agreement between the iPPG-based evaluations and both the qualitative and quantitative dimensions of the ICG standard.

Detailed description

This randomized, parallel-group clinical study aims to compare two intraoperative imaging strategies for assessing tissue perfusion in a spectrum of gastrointestinal anastomoses, including both gastro-intestinal and entero-enteric reconstructions. The primary objective is to evaluate the diagnostic performance and clinical utility of a novel, non-contact optical technique-imaging photoplethysmography (iPPG)-against the current clinical standard, indocyanine green (ICG) fluorescence imaging. Eligible and consented patients will be randomly assigned to one of two arms. The iPPG Arm will undergo perfusion evaluation solely using the investigational iPPG system. This method leverages a conventional video camera to detect pulsatile blood volume changes in microvascular tissue, offering a non-invasive, contrast-agent-free approach to perfusion assessment. The ICG Arm will be assessed using the standard fluorescence imaging protocol. A key feature of the study design is the pre-specified, comprehensive analysis within the ICG arm, which will incorporate both a qualitative assessment (the surgeon's real-time visual interpretation of the angiogram) and a quantitative analysis (computer-based calculation of fluorescence kinetics parameters, such as time-to-peak and inflow slope). The study is designed to provide a head-to-head comparison of the two guiding strategies. Outcomes from the iPPG-guided arm will be systematically benchmarked against those from the ICG-guided arm. Furthermore, the internal comparison between qualitative and quantitative assessments within the ICG arm will yield valuable insights into the optimal methodology for interpreting perfusion data in clinical practice. This design allows for the evaluation of iPPG not only as a potential alternative to ICG but also for the refinement of the standard itself.

Conditions

• Anastomosis
• Perfusion
• Postoperative Complications
• Gastrointestinal Neoplasms
• Gastric Cancer (GC)
• Colorectal Cancer

Interventions

Type	Name	Description
DRUG	ICG fluorescence imaging technology	This intervention involves the intravenous injection of the fluorescent contrast agent Indocyanine Green (ICG), followed by imaging with a near-infrared fluorescence camera system. Upon illumination with near-infrared light, ICG in the bloodstream fluoresces, allowing for real-time visualization of blood flow and tissue perfusion (qualitative assessment). Additionally, the fluorescence intensity over time can be recorded for subsequent quantitative analysis of perfusion kinetics.
DEVICE	Imaging Photoplethysmography System	Imaging photoplethysmography is a non-contact, camera-based optical imaging technique. This investigational system operates by detecting subtle modulations in optical signals associated with pulsatile blood volume changes in microvascular tissue. It utilizes a conventional video camera to capture these signals and generates real-time tissue perfusion maps without the need for any exogenous contrast agents. The system is designed to provide intraoperative guidance for assessing tissue viability during gastrointestinal anastomoses.

Timeline

• Start date: 2023-11-01
• Primary completion: 2026-04-30
• Completion: 2026-05-31
• First posted: 2024-01-25
• Last updated: 2025-11-18

Locations

3 sites across 2 countries: China, Russia