# Objective Perfusion Assessment With Near Infrared Fluorescence for Guidance of Bowel Resection Margins Following Superior Mesenteric Artery Thrombosis: A Case Report

## TL;DR

This case report shows how near infrared fluorescence imaging can help surgeons assess bowel perfusion and make better decisions during surgery for superior mesenteric artery thrombosis.

## Contribution

Demonstrates the practical use of NIRF imaging for objective perfusion assessment during SMA embolectomy in a clinical case.

## Key findings

- NIRF imaging identified malperfusion in a jejunal segment pre- and post-embolectomy.
- Quantitative fluorescence analysis showed clear percentage differences in perfusion between viable and ischaemic tissue.
- NIRF imaging helped guide resection and anastomosis, preserving viable bowel tissue.

## Abstract

Acute occlusion of the superior mesenteric artery (SMA) results in extensive bowel ischaemia, with mortality rates approaching 70%. Management involves acute revascularisation, typically via embolectomy, and intra-operative evaluation to distinguish viable from non-viable intestinal tissue. Near infrared fluorescence (NIRF) imaging with indocyanine green (ICG) enables real time, minimally invasive assessment of tissue perfusion. This case report illustrates the usability of NIRF imaging to guide surgical decision making for bowel preservation and patient survival in a clinical situation where research is limited.

A 40 year old male presented, in June 2023, with severe postprandial abdominal pain. Imaging revealed a non-occlusive thrombus in the SMA, which together with clinical deterioration resulted in an emergency embolectomy. Intra-operative NIRF imaging with ICG identified malperfusion of a jejunal segment. A second NIRF assessment post-embolectomy confirmed persistent malperfusion, guiding resection with a primary anastomosis. Quantitative fluorescence analysis confirmed the intra-operative findings of malperfusion and demonstrated potential utility for objective perfusion assessment to resect non-viable tissue and limit viable tissue resection. The patient recovered uneventfully and was discharged on post-operative day five.

This case highlights the use of NIRF imaging as a safe, low cost technique for evaluating bowel perfusion during SMA embolectomy. By selecting adjacent regions of interest, surgeons can compare objective perfusion curves intra-operatively and select optimal anastomosis sites. Quantified parameters further aid decision making, showing clear percentage differences in perfusion between viable and ischaemic tissue. Although standardised cut off values are lacking, combining clinical evaluation, subjective assessment, and quantitative data offers a patient tailored approach to optimising resection margins.

•Current assessment tools lack accuracy in predicting ischaemia during superior mesenteric artery (SMA) occlusion.•Fluorescence imaging aids in bowel perfusion assessment during SMA embolectomy.•Quantified perfusion curves and parameters enhance resection margin determination.•Fluorescence imaging helps preserve viable tissue and maintain bowel function.

Current assessment tools lack accuracy in predicting ischaemia during superior mesenteric artery (SMA) occlusion.

Fluorescence imaging aids in bowel perfusion assessment during SMA embolectomy.

Quantified perfusion curves and parameters enhance resection margin determination.

Fluorescence imaging helps preserve viable tissue and maintain bowel function.