_version_ 1866913976890163200
author Li, Wenjie
Zhang, Yujie
Sun, Haoran
Li, Yueqi
Zhang, Fanrui
Xu, Mengzhe
Clausich, Victoria Borja
Mellin, Sade
Yang, Renhao
Wang, Chenrun
Wang, Jethro Zih-Shuo
Yao, Shiyi
Li, Gen
Xu, Yidong
Wang, Hanyu
Huang, Yilin
Wang, Angela Lin
Shi, Chen
Zhang, Yin
Guo, Jianan
Yang, Luqi
Li, Renxuan
Xu, Yang
Liu, Jiawei
Zhang, Yao
Liu, Lei
SanRomán, Carlos Gutiérrez
Wang, Lei
author_facet Li, Wenjie
Zhang, Yujie
Sun, Haoran
Li, Yueqi
Zhang, Fanrui
Xu, Mengzhe
Clausich, Victoria Borja
Mellin, Sade
Yang, Renhao
Wang, Chenrun
Wang, Jethro Zih-Shuo
Yao, Shiyi
Li, Gen
Xu, Yidong
Wang, Hanyu
Huang, Yilin
Wang, Angela Lin
Shi, Chen
Zhang, Yin
Guo, Jianan
Yang, Luqi
Li, Renxuan
Xu, Yang
Liu, Jiawei
Zhang, Yao
Liu, Lei
SanRomán, Carlos Gutiérrez
Wang, Lei
contents Chest X-ray (CXR) imaging is one of the most widely used diagnostic modalities in clinical practice, encompassing a broad spectrum of diagnostic tasks. Recent advancements have seen the extensive application of reasoning-based multimodal large language models (MLLMs) in medical imaging to enhance diagnostic efficiency and interpretability. However, existing multimodal models predominantly rely on "one-time" diagnostic approaches, lacking verifiable supervision of the reasoning process. This leads to challenges in multi-task CXR diagnosis, including lengthy reasoning, sparse rewards, and frequent hallucinations. To address these issues, we propose CX-Mind, the first generative model to achieve interleaved "think-answer" reasoning for CXR tasks, driven by curriculum-based reinforcement learning and verifiable process rewards (CuRL-VPR). Specifically, we constructed an instruction-tuning dataset, CX-Set, comprising 708,473 images and 2,619,148 samples, and generated 42,828 high-quality interleaved reasoning data points supervised by clinical reports. Optimization was conducted in two stages under the Group Relative Policy Optimization framework: initially stabilizing basic reasoning with closed-domain tasks, followed by transfer to open-domain diagnostics, incorporating rule-based conditional process rewards to bypass the need for pretrained reward models. Extensive experimental results demonstrate that CX-Mind significantly outperforms existing medical and general-domain MLLMs in visual understanding, text generation, and spatiotemporal alignment, achieving an average performance improvement of 25.1% over comparable CXR-specific models. On real-world clinical dataset (Rui-CXR), CX-Mind achieves a mean recall@1 across 14 diseases that substantially surpasses the second-best results, with multi-center expert evaluations further confirming its clinical utility across multiple dimensions.
format Preprint
id arxiv_https___arxiv_org_abs_2508_03733
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle CX-Mind: A Pioneering Multimodal Large Language Model for Interleaved Reasoning in Chest X-ray via Curriculum-Guided Reinforcement Learning
Li, Wenjie
Zhang, Yujie
Sun, Haoran
Li, Yueqi
Zhang, Fanrui
Xu, Mengzhe
Clausich, Victoria Borja
Mellin, Sade
Yang, Renhao
Wang, Chenrun
Wang, Jethro Zih-Shuo
Yao, Shiyi
Li, Gen
Xu, Yidong
Wang, Hanyu
Huang, Yilin
Wang, Angela Lin
Shi, Chen
Zhang, Yin
Guo, Jianan
Yang, Luqi
Li, Renxuan
Xu, Yang
Liu, Jiawei
Zhang, Yao
Liu, Lei
SanRomán, Carlos Gutiérrez
Wang, Lei
Machine Learning
Artificial Intelligence
Computation and Language
Computer Vision and Pattern Recognition
Chest X-ray (CXR) imaging is one of the most widely used diagnostic modalities in clinical practice, encompassing a broad spectrum of diagnostic tasks. Recent advancements have seen the extensive application of reasoning-based multimodal large language models (MLLMs) in medical imaging to enhance diagnostic efficiency and interpretability. However, existing multimodal models predominantly rely on "one-time" diagnostic approaches, lacking verifiable supervision of the reasoning process. This leads to challenges in multi-task CXR diagnosis, including lengthy reasoning, sparse rewards, and frequent hallucinations. To address these issues, we propose CX-Mind, the first generative model to achieve interleaved "think-answer" reasoning for CXR tasks, driven by curriculum-based reinforcement learning and verifiable process rewards (CuRL-VPR). Specifically, we constructed an instruction-tuning dataset, CX-Set, comprising 708,473 images and 2,619,148 samples, and generated 42,828 high-quality interleaved reasoning data points supervised by clinical reports. Optimization was conducted in two stages under the Group Relative Policy Optimization framework: initially stabilizing basic reasoning with closed-domain tasks, followed by transfer to open-domain diagnostics, incorporating rule-based conditional process rewards to bypass the need for pretrained reward models. Extensive experimental results demonstrate that CX-Mind significantly outperforms existing medical and general-domain MLLMs in visual understanding, text generation, and spatiotemporal alignment, achieving an average performance improvement of 25.1% over comparable CXR-specific models. On real-world clinical dataset (Rui-CXR), CX-Mind achieves a mean recall@1 across 14 diseases that substantially surpasses the second-best results, with multi-center expert evaluations further confirming its clinical utility across multiple dimensions.
title CX-Mind: A Pioneering Multimodal Large Language Model for Interleaved Reasoning in Chest X-ray via Curriculum-Guided Reinforcement Learning
topic Machine Learning
Artificial Intelligence
Computation and Language
Computer Vision and Pattern Recognition
url https://arxiv.org/abs/2508.03733