Intraoperative Doppler Ultrasonography with Superb Microvascular Imaging for Intestinal Perfusion Assessment in...

Area of Science:

• Surgical Oncology
• Medical Imaging
• Vascular Imaging

Background:

• Intraoperative indocyanine green fluorescence imaging (ICG-FI) aids in reducing anastomotic leakage in colorectal surgery.
• Limitations of ICG-FI include contrast agent use, repeatability issues, and timing-dependent interpretation.
• There is a need for alternative methods to assess intestinal perfusion during surgery.

Purpose of the Study:

• To explore the utility of Doppler ultrasonography with superb microvascular imaging (SMI) for assessing intestinal perfusion during colorectal cancer surgery.
• To compare the perfusion boundary identified by SMI with that identified by ICG-FI.
• To evaluate the inter-observer reproducibility and safety of the SMI method.

Main Methods:

• A single-center prospective pilot study enrolled patients undergoing colorectal cancer resection with anastomosis.
• Intramural microvascular flow was assessed using SMI to determine the perfusion boundary, followed by ICG-FI.
• The primary endpoint was the difference in blood flow boundaries between ICG-FI and SMI; secondary endpoints included inter-observer reproducibility and safety.

Main Results:

• The median difference in perfusion boundaries between ICG-FI and SMI was -4 mm, with SMI indicating a more proximal boundary.
• Inter-observer variability for SMI boundary detection showed a median absolute difference of 2 mm.
• The SMI method was technically feasible, with analyzable data obtained in seven of eight patients, and no procedure-related adverse events occurred.

Conclusions:

• Intraoperative SMI is a technically feasible and reproducible method for assessing intestinal perfusion boundaries during colorectal cancer surgery.
• Differences exist in perfusion boundary location between SMI and ICG-FI.
• Further prospective validation is required for clinical implementation of SMI.