# Karl Hahn > Software and Machine Learning Engineer Location: San Francisco Bay Area, United States Profile: https://flows.cv/karlhahn ## Work Experience ### Senior Software Engineer @ DeepSight Technology Jan 2025 – Present ### Associate Research Scientist @ HeartFlow, Inc Jan 2018 – Jan 2023 • HeartFlow-Imperial College London collaboration on deep learning-based CCTA reconstruction and multi-phase image registration. • Conception, development, and training of deep learning (DL) image registration models on large 3D multiphase coronary computed tomography angiography (CCTA) datasets for construction of cardiac motion models suitable for simulation-based data augmentation of CT acquisition and reconstruction. • Conception, development, and training of DL coronary artery motion quantification from single 3D CCTA images to detect and quantify cardiac motion from CT reconstruction motion artifact signature. • Implemented CUDA-accelerated PyTorch operator for differentiable B-spline deformation field sampling. • Implemented tools to parse and curate multiphase CCTA DICOM files. • Developed interactive, point-to-surface 3D image annotation tool built on Slicer 3D for manual segmentation of cardiac anatomy. ### Senior Imaging Algorithms Engineer @ HeartFlow, Inc Jan 2017 – Jan 2018 • Led transition of Image Analysis team deep learning framework to TensorFlow. • Thought leader for cross-functional proposal to revamp Production Image Quality Assessment process to produce ‘learnable data’ to realize virtuous cycle of automation, learnable human correction, automation improvement. • Scrum master for Image Analysis sub-team. • Training and supervision of new hire algorithms engineer. • Reformulated TensorFlow CMake build system to support dynamic linkage against internal super builds of TensorFlow dependencies. • Implemented TensorFlow support for user-encrypted model persistence leveraging TensorFlow’s memory mapped filesystem. • C++ development support for next generation, deep learning-based centerline extraction and lumen segmentation. ### Associate Medical Imaging Scientist @ HeartFlow, Inc Jan 2014 – Jan 2017 • Development and application of active shape model framework for cardiac chamber segmentation. • Artifact detection in cardiac computed tomography angiography images (motion, blooming, misalignment) to support Production Image Quality Assessment process. • Design and implementation of tools to parcellate Left Ventricular Myocardium segmentation according to AHA 17-segment model. ### Biomedical Engineer @ HeartFlow, Inc Jan 2011 – Jan 2014 | Redwood City, CA • Product management, design, implementation, and testing of C#/WPF-based frontend intermediary between Production Workstation for review and correction of image analysis automation results and Production Backend. • Workflow design for development of next generation Production Workstation. • Participation in pre-commercial case processing for DEFACTO clinical study. • Evaluation of coronary artery lesion segmentation and centerline extraction algorithms. • Generation and curation of product design documentation for 510K FDA filing. ## Education ### Master of Science - MS in Mechanical Engineering Stanford University ### Bachelor of Science - BS in Biomedical Engineering Texas A&M University ## Contact & Social - LinkedIn: https://linkedin.com/in/karl-hahn-a2467336 --- Source: https://flows.cv/karlhahn JSON Resume: https://flows.cv/karlhahn/resume.json Last updated: 2026-04-01