医学图像分割和语言模型终于打通了，MedPixel一个模型搞定定位加问答，还自带44万样本的数据集，搞医学AI的值得看看。
MedPixel是一个统一的医学像素-语言模型，通过共享的语言-掩码接口连接临床语言、视觉推理与像素级定位。研究团队构建了MedPLG-440K数据集，包含约44万个像素-语言任务样本，通过临床驱动的合成流程生成，无需外部LLM标注。模型采用联合多任务监督微调和像素级偏好优化训练，后者利用真实掩码作为离线验证器，从掩码质量推导响应偏好。MedPixel支持显式定位、隐式推理、空间交互、可解释分割和医学VQA等任务，在像素级预测和响应生成上均表现强劲，并具备对零样本外部基准和模糊空间提示的鲁棒性。
MedPixel: A Unified Pixel-Language Model for Medical Reasoning and Segmentation
Reliable medical image understanding requires models to connect clinical language and visual reasoning with pixel-level grounding. Yet medical vision-language models often lack precise localization, whereas medical segmenters typically rely on explicit target categories or precise spatial prompts. This divide is reinforced by a supervision mismatch: segmentation datasets provide precise masks but little language supervision, whereas medical vision-language data rarely pair language with dense spatial annotations. To address this gap, we present MedPixel, a unified medical pixel-language model built around a shared language--mask interface. To provide scalable supervision, we introduce MedPLG-440K, comprising approximately 440K pixel-language task samples constructed through a clinically motivated synthesis process without external LLM annotation. MedPixel is trained with joint multi-task supervised fine-tuning followed by Pixel-Level Preference Optimization, which uses ground-truth masks as offline verifiers to derive response preferences from mask quality. MedPixel supports a broad spectrum of tasks spanning explicit grounding, implicit reasoning, spatial interaction, grounded explanation, and medical VQA. Across this task spectrum, MedPixel achieves strong performance in both pixel-level prediction and response generation, together with effective zero-shot transfer to external grounding benchmarks and robustness to imperfect spatial prompts. Code and model checkpoints will be released at https://github.com/yhy-whu/Medpixel.