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Yiheng Li李易恒

Research Staff · Stanford University School of Medicine医学深度学习研究员 · 斯坦福大学医学院
Division of Computational Medicine · Palo Alto, CA计算医学部 · 加州帕洛阿尔托

I build self-supervised foundation models for cancer imaging — pretrained on unlabeled 3D scans, fused with pathology and clinical records, and held to the questions oncology actually asks: a tumor's genotype, how far it has spread, how it responds to treatment over time.我做的是面向肿瘤影像的自监督基础模型——在无标注的三维影像上预训练,再与病理和临床数据融合,用来回答肿瘤学真正关心的问题:肿瘤的基因型、扩散到了哪一步、以及随时间如何响应治疗。

Focus方向
Medical imaging医学影像 Image registration图像配准 Quality control质量控制 Self-supervised learning自监督学习 Multimodal fusion多模态融合 LoRA / diffusionLoRA / 扩散模型

Experience经历

09/2023—

Research Staff研究员

STANFORD MEDICINE · GEVAERT LAB, COMPUTATIONAL MEDICINE斯坦福医学院 · 计算医学部 GEVAERT 实验室

Self-supervised foundation models for cancer imaging: a 3D β-VAE that learns lung-tumour morphology from unlabelled CT and transfers to nodal-stage and KRAS prediction; multi-modal COVID-19 triage from CT radiomics and clinical records; supervised pre-training for glaucoma detection on fundus photographs.面向肿瘤影像的自监督基础模型:一个三维 β-VAE,从无标注 CT 中学习肺部肿瘤形态,并迁移到淋巴结分期与 KRAS 突变预测;结合 CT 影像组学与临床记录的多模态 COVID-19 分诊;以及用于眼底照片青光眼检测的有监督预训练。

08/2021—08/2023

Deep Learning Research Scientist深度学习研究科学家

SUBTLE MEDICAL · MENLO PARK, CASUBTLE MEDICAL · 加州门洛帕克

Registration, registration QC, and self-supervised keypoint detection for 3D MRI. Four accepted meeting abstracts across ISMRM, ASNR and RSNA.三维 MRI 的配准、配准质量控制与自监督关键点检测。四篇会议摘要分别被 ISMRM、ASNR 与 RSNA 接收。

07/2020—07/2021

Research Assistant助理研究员

STANFORD UNIVERSITY · BMI斯坦福大学 · 生物医学信息学

Three labs alongside the MSc. In Dr. David Camarillo's lab: head-impact biomechanics and brain-strain modelling, which became five co-authored papers. In Dr. Olivier Gevaert's lab: multi-modal pre-training — SimCLR, BYOL, DINO — across pathology, CT and EHR. In Dr. Akshay Chaudhari's lab: a U-Net vertebral segmentation pipeline for the Opportunistic CT initiative.硕士期间同时在三个实验室。David Camarillo 教授实验室:头部撞击生物力学与脑应变建模,最终有五篇合著论文。Olivier Gevaert 教授实验室:跨病理、CT 与电子病历的多模态预训练(SimCLR、BYOL、DINO)。Akshay Chaudhari 教授实验室:为 Opportunistic CT 项目搭建的 U-Net 椎体分割流水线。

Selected work研究

2023—2024

A 3D lung lesion variational autoencoder三维肺部病灶变分自编码器

A 3D β-VAE that learns lung-tumour morphology from unlabelled CT — no manual labels — reconstructing nodule volumes at SSIM 0.774 and PSNR 26.1 while compressing them into a compact latent code. Individual latent dimensions turn out to track clinical characteristics such as nodule size, so moving along them synthesises plausible lesions; the same embeddings, transferred to an independent radiogenomic cohort, predict pathological nodal stage and KRAS mutation status on par with fully supervised models.一个三维 β-VAE,不用人工标注,直接从无标签 CT 中学习肺部肿瘤形态:重建结节体数据的 SSIM 为 0.774、PSNR 为 26.1,同时把它压缩成一段紧凑的隐编码。隐空间的单个维度与结节大小等临床特征高度相关,沿着这些方向移动即可合成看起来合理的新病灶;把同一套嵌入迁移到独立的影像基因组队列上,对病理淋巴结分期与 KRAS 突变状态的预测可与全监督模型持平。

PYTORCH · β-VAE · RADIOGENOMICSPYTORCH · β-VAE · 影像基因组学

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FIG. 2 · CELL REPORTS METHODS 2024 · CC BY-NC-NDFIG. 2 · CELL REPORTS METHODS 2024 · CC BY-NC-ND
2024—2025

Glaucoma detection by supervised pre-training on intermediate phenotypes以中间表型做有监督预训练的青光眼检测

Pre-training on a clinically meaningful intermediate marker — the vertical cup-to-disc ratio — rather than on ImageNet or a self-supervised proxy. A multi-task setup learns diagnosis and VCDR regression together on AIROGS, then transfers to six independent cohorts (DRISHTI, G1020, ORIGA, PAPILA, REFUGE1, ACRIMA). It beats out-of-domain and self-supervised pre-training on every backbone tried: ResNet-18, DINOv2 and RETFound.预训练的目标不是 ImageNet,也不是某个自监督代理任务,而是一个临床上真正有意义的中间指标——垂直杯盘比(VCDR)。模型在 AIROGS 上以多任务方式同时学习诊断分类与 VCDR 回归,再迁移到六个独立队列(DRISHTI、G1020、ORIGA、PAPILA、REFUGE1、ACRIMA)。在试过的每一个骨干网络上——ResNet-18、DINOv2 与 RETFound——它都优于域外预训练与自监督预训练。

PYTORCH · MULTI-TASK · RETFOUND / DINOV2PYTORCH · 多任务 · RETFOUND / DINOV2

2024—2025

Benchmarking chest X-ray diagnosis models across multinational datasets跨国数据集上的胸片诊断模型基准评测

Do vision–language foundation models actually generalise better than a plain CNN? Five of them (CheXzero, BioViL-T, MAVL, MedKLIP, PsPG) and three CNNs (DenseNet, ResNet, X-Raydar) put through 37 standardised classification tasks over six public datasets from the USA, Spain, India and Vietnam, plus three previously unreleased hospital datasets from China.视觉—语言基础模型是否真的比普通 CNN 泛化得更好?把五个基础模型(CheXzero、BioViL-T、MAVL、MedKLIP、PsPG)与三个 CNN(DenseNet、ResNet、X-Raydar)放在 37 项标准化分类任务上评测,数据来自美国、西班牙、印度与越南的六个公开数据集,外加三个此前未公开的中国医院数据集。

FOUNDATION MODELS · EXTERNAL VALIDATION基础模型 · 外部验证

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ARXIV:2505.16027ARXIV:2505.16027
2020—2021

AI-based CT triage of COVID-19 patients基于人工智能的 COVID-19 患者 CT 分诊

A multi-modal triage model joining 9,943 chest-CT radiomic features to clinical and laboratory records, predicting the outcomes that decide care — ICU admission, mechanical ventilation, death. Trained on a multi-hospital cohort of 1,662 patients and externally validated on 1,362 more, at AUROC ~0.85—0.94 across tasks.一个多模态分诊模型,把 9,943 项胸部 CT 影像组学特征与临床及实验室记录联合起来,预测真正决定治疗方案的结局——ICU 收治、机械通气与死亡。在 1,662 例患者的多中心队列上训练,并在另外 1,362 例上做外部验证,各任务 AUROC 约 0.85—0.94。

RADIOMICS · MULTI-MODAL · SURVIVAL影像组学 · 多模态 · 生存分析

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FIG. 5 · NPJ DIGITAL MEDICINE 2021 · CC BYFIG. 5 · NPJ DIGITAL MEDICINE 2021 · CC BY
02/2022—09/2022

Multi-contrast MRI registration with a realistic flow field带真实形变场的多对比度 MRI 配准

Ported SynthMorph from TensorFlow to PyTorch and trained variants with Jacobian and cycle-consistency losses to fight unrealistic flow fields and over-smoothing in the VoxelMorph family. ~40% SSIM and ~50% PSNR improvement over baseline on BraTS and Lumbar-Spine.把 SynthMorph 从 TensorFlow 移植到 PyTorch,训练了带雅可比与循环一致性损失的多个变体,用来抑制 VoxelMorph 系列中不真实的形变场与过度平滑。在 BraTS 与腰椎数据上,SSIM 较基线提升约 40%,PSNR 提升约 50%。

PYTORCH · SYNTHMORPH · VOXELMORPHPYTORCH · SYNTHMORPH · VOXELMORPH

08/2021—02/2022

Deep learning based image co-registration quality control基于深度学习的图像配准质量控制

A self-supervised classifier for registration quality on 3D MRI pairs, trained on synthetically mis-registered volumes from an affine plus deformable augmentation pipeline — the labelled failure cases don't exist in the wild, so we manufactured them. Trained on synthetic contrasts alone, it generalises to real brain and spine MRI better than a model trained on either of them.一个针对三维 MRI 图像对的自监督配准质量分类器,训练数据来自仿射加形变增强流水线合成的错配体数据——真实世界里没有带标注的失败样本,于是我们自己造。只用合成对比度训练的模型,在真实脑部与脊柱 MRI 上的泛化性反而好过在其中任一数据集上训练的模型。

PYTORCH · 3D CNN · SELF-SUPERVISIONPYTORCH · 3D CNN · 自监督

2020—2023

Head-impact kinematics and brain-strain prediction头部撞击运动学与脑应变预测

Five co-authored papers on what measurable head kinematics can and cannot say about brain injury: impact subtyping from the spectral densities of the kinematics (J. Sport Health Sci. 2023), piecewise multivariate linearity between kinematic features and the cumulative strain damage measure (Ann. Biomed. Eng. 2022), how far brain injury criteria and simulated strain diverge across impact types (J. R. Soc. Interface 2021), the measurement time window needed for reliable strain and strain-rate estimates, and a statistical reading of which kinematic features actually carry the prediction.五篇合著论文,讨论可测量的头部运动学到底能、以及不能说明脑损伤的哪些方面:基于运动学功率谱密度的撞击亚型划分(J. Sport Health Sci. 2023);运动学特征与累积应变损伤指标(CSDM)之间的分段多元线性关系(Ann. Biomed. Eng. 2022);不同撞击类型下脑损伤判据与仿真应变的分歧程度(J. R. Soc. Interface 2021);可靠估计应变与应变率所需的测量时间窗;以及从统计角度看究竟哪些运动学特征真正承担了预测。

MACHINE LEARNING · BIOMECHANICS · STATISTICS机器学习 · 生物力学 · 统计

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FIG. 1 · J SPORT HEALTH SCI 2023 · CC BY-NC-NDFIG. 1 · J SPORT HEALTH SCI 2023 · CC BY-NC-ND
2022—

Lumos-ToolKitLumos-ToolKit

My own PyTorch-Lightning and MONAI toolkit for training, logging and inference — the parts of medical imaging research nobody wants to write twice. Not released yet; the repository is still private while it is cleaned up.我自己写的一套基于 PyTorch Lightning 与 MONAI 的训练、日志与推理工具包,覆盖医学影像研究里没人想写第二遍的那些部分。尚未发布,仓库仍是私有的,还在整理中。

PERSONAL · OPEN SOURCE · PYTHON个人项目 · 开源 · PYTHON

Accepted abstracts会议摘要

RSNA 2022RSNA 2022 Deep learning quality control for multi-contrast brain MRI alignment多对比度脑 MRI 对齐的深度学习质量控制

Education教育

09/2019—06/2021
Stanford University斯坦福大学 M.Sc. Biomedical Informatics生物医学信息学 理学硕士
09/2015—06/2019
Shanghai Jiao Tong University上海交通大学 B.Sc. Resource and Environmental Science资源与环境科学 理学学士
01/2018—05/2018
University of California, Berkeley加州大学伯克利分校 International Exchange Program国际交换项目

Skills技能

Languages语言 Python, R, SQL, MATLAB, BashPython, R, SQL, MATLAB, Bash
Frameworks框架 PyTorch, PyTorch Lightning, MONAI, ANTs, scikit-learn, TensorFlowPyTorch, PyTorch Lightning, MONAI, ANTs, scikit-learn, TensorFlow
Imaging影像 3D MRI, registration, segmentation, radiomics, DICOM / NIfTI pipelines三维 MRI、配准、分割、影像组学、DICOM / NIfTI 流水线
Statistics统计 Survival analysis, GLMs, mixed models, experimental design生存分析、广义线性模型、混合效应模型、实验设计

Other projects其他项目

01 Repression effect of protein tiles from HT-recruit RNA-seq基于 HT-recruit RNA-seq 的蛋白片段抑制效应 BIOMEDIN 273B · DEEP LEARNING IN GENOMICSBIOMEDIN 273B · 基因组学中的深度学习 2020 fall2020 年秋 02 Meta-learning for head impact strain across datasets跨数据集的头部撞击应变元学习 CS 330 · DEEP MULTI-TASK AND META LEARNINGCS 330 · 深度多任务与元学习 2020 fall2020 年秋 03 Transfer learning for pneumothorax detection on chest X-ray胸片气胸检测的迁移学习 BIOMEDIN 260 · BIOMEDICAL IMAGE ANALYSISBIOMEDIN 260 · 生物医学图像分析 2020 spring2020 年春 04 Two open-topic deep learning projects两个自选题深度学习项目 CS 230 · CS 229 · POSTERS AND REPORTSCS 230 · CS 229 · 海报与报告 2019 — 20202019 — 2020

About关于

I'm Yiheng Li — Terry to most people. Outside work: guitar, singing, travel, badminton.我是李易恒,多数人叫我 Terry。工作之外:吉他、唱歌、旅行、羽毛球。

How this site is made这个站点是怎么做的

Astro, hosted on GitHub Pages. Hugo + PaperMod before that, Hexo + NexT before that. Type is Spectral, IBM Plex Mono, and Noto Serif SC.Astro 搭建,托管在 GitHub Pages。此前是 Hugo + PaperMod,更早是 Hexo + NexT。字体为 Spectral、IBM Plex Mono 与思源宋体。

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