Lymph Node Detection in T2 MRI with Transformers

TL;DR

This paper introduces a Transformer-based method for detecting lymph nodes in T2 MRI scans, achieving improved accuracy and sensitivity over previous approaches, aiding in better cancer staging.

Contribution

The study applies the DETR network to lymph node detection in T2 MRI, incorporating a bounding box fusion technique to reduce false positives, and demonstrates superior performance compared to existing methods.

Findings

Achieved 65.41% precision and 91.66% sensitivity at 4 false positives per image.

Improved detection performance over current state-of-the-art methods.

Validated robustness across different scanners and protocols.

Abstract

Identification of lymph nodes (LN) in T2 Magnetic Resonance Imaging (MRI) is an important step performed by radiologists during the assessment of lymphoproliferative diseases. The size of the nodes play a crucial role in their staging, and radiologists sometimes use an additional contrast sequence such as diffusion weighted imaging (DWI) for confirmation. However, lymph nodes have diverse appearances in T2 MRI scans, making it tough to stage for metastasis. Furthermore, radiologists often miss smaller metastatic lymph nodes over the course of a busy day. To deal with these issues, we propose to use the DEtection TRansformer (DETR) network to localize suspicious metastatic lymph nodes for staging in challenging T2 MRI scans acquired by different scanners and exam protocols. False positives (FP) were reduced through a bounding box fusion technique, and a precision of 65.41\% and sensitivity of 91.66\% at 4 FP per image was achieved. To the best of our knowledge, our results improve upon the current state-of-the-art for lymph node detection in T2 MRI scans.