🔥 FLARE23 Solution

This repository contains our solution for the FLARE23 challenge, based on nnU-Netv2.

For a detailed explanation of our specific methods and approaches, you can refer to our paper: Exploiting Pseudo-Labeling and nnU-Netv2 Inference Acceleration for Abdominal Multi-Organ and Pan-Cancer Segmentation.

🔍 Overview

Our approach employs a two-stage pseudo-labeling method to tackle the issue of partial labels for organs and tumors in the FLARE23 dataset. For more details, see the pipeline diagram below:

Additionally, we present a speed comparison for inference, both before and after optimizations on nnU-Netv2. The following diagram illustrates the improvements:

⚙️ Environment Setup

To set up the environment, follow these steps:

conda create -n FLARE23_blackbean
conda activate FLARE23_blackbean

Then make sure to install PyTorch 2 compatible with your CUDA version.

pip install -e .

🚂 Train

Training our nnU-Netv2 model consists of five main steps, as depicted in the pipeline figure above. Follow these instructions to conduct the training process effectively:

Step 1: Large Organ Model Training

Firstly, prepare a dataset of 250 images with 13-organ labels. Use this dataset to train a large organ model.

nnUNetv2_train TASK_ID 3d_fullres all -tr STUNetTrainer_large

Step 2: Generate Pseudo Labels for Tumor Images

With the model trained in Step 1, generate pseudo labels for 1494 tumor-annotated images.

nnUNetv2_predict -i INPUT_FOLDER -o OUTPUT_FOLDER -d TASK_ID -c 3d_fullres -f all -tr STUNetTrainer_large

Step 3: Merge Labels and Train Large Model

Merge the pseudo organ labels and actual tumor labels in 1497 images, and then train a large model using this merged dataset.

nnUNetv2_train TASK_ID 3d_fullres all -tr STUNetTrainer_large

Step 4: Generate Pseudo Labels for All Images

Using the model trained in Step 3, generate pseudo labels for all 4000 images in the dataset.

nnUNetv2_predict -i INPUT_FOLDER -o OUTPUT_FOLDER -d TASK_ID -c 3d_fullres -f all -tr STUNetTrainer_large

Step 5: Train Small Model for Deployment

Finally, train a small model on the dataset of 4000 images. This model will be used for deployment.

nnUNetv2_train TASK_ID 3d_fullres all -tr STUNetTrainer_base

⬇️ Download Checkpoints

Download the checkpoint_final.pth file from BaiduNetDisk or Google Drive. Place it in the ./model/fold_all/ directory.

🚀 Inference

1. Place your input images in the ./inputs directory.
2. Run the prediction script:

sh predict.sh

This will generate the output in the ./outputs directory.