MRI Plane Orientation Detection using a Context-Aware 2.5D Model

TL;DR

This paper presents a context-aware 2.5D model for accurately detecting MRI plane orientations, significantly improving metadata generation and enhancing brain tumor detection accuracy through a gated strategy.

Contribution

The study introduces a novel 2.5D context-aware approach for MRI plane orientation detection, outperforming 2D models and demonstrating practical utility in diagnostic tasks.

Findings

2.5D model achieves 99.49% accuracy, surpassing 2D reference by 0.75%.

Metadata improves brain tumor detection accuracy from 97.0% to 98.0%.

Metadata-based predictions reduce misdiagnoses by 33.3%.

Abstract

Humans can easily identify anatomical planes (axial, coronal, and sagittal) on a 2D MRI slice, but automated systems struggle with this task. Missing plane orientation metadata can complicate analysis, increase domain shift when merging heterogeneous datasets, and reduce accuracy of diagnostic classifiers. This study develops a classifier that accurately generates plane orientation metadata. We adopt a 2.5D context-aware model that leverages multi-slice information to avoid ambiguity from isolated slices and enable robust feature learning. We train the 2.5D model on both 3D slice sequences and static 2D images. While our 2D reference model achieves 98.74% accuracy, our 2.5D method raises this to 99.49%, reducing errors by 60%, highlighting the importance of 2.5D context. We validate the utility of our generated metadata in a brain tumor detection task. A gated strategy selectively uses metadata-enhanced predictions based on uncertainty scores, boosting accuracy from 97.0% with an image-only model to 98.0%, reducing misdiagnoses by 33.3%. We integrate our plane orientation model into an interactive web application and provide it open-source.