# Automatic Couinaud segmentation using AI and pictorial representation landmarking

## TL;DR

This paper introduces an AI framework that improves the accuracy of liver segment segmentation for surgery and monitoring.

## Contribution

A novel AI framework combining deep learning and landmark identification for precise Couinaud segmentation.

## Key findings

- The personalized model outperformed benchmarks in 5/8 landmarks and 7/8 segments.
- The system is explainable, modality-agnostic, and scalable across clinical contexts.
- It reduces the need for retraining when incorporating new data.

## Abstract

Delineating the Couinaud segments is a critical component of liver surgery and monitoring that has traditionally relied on labor-intensive methods that are prone to variability. While fully or semi-automatic methods exist, they generally lack accuracy or require extensive post-processing or corrections to the outputs.

We present a framework that integrates deep learning-based segmentation with auxiliary landmark identification to create a personalized pictorial model on which to base precise Couinaud landmark localization. Data from 225 non-contrast T1-weighted MRIs from 4 different studies were used to evaluate the performance against benchmark techniques and human-defined ground truth.

The personalized model outperformed the benchmark method in every landmark placement and Couinaud segment volume estimation, being significantly better in 5/8 landmarks and 7/8 segments.

The proposed system is explainable, agnostic to imaging modality and is able to incorporate new data without retraining, enhancing its robustness and scalability across diverse clinical contexts. These findings underscore the potential of our framework to substantially improve Couinaud accuracy and streamline clinical workflows, optimizing liver surgery planning and monitoring.

The online version contains supplementary material available at 10.1007/s00261-025-05123-3.