Nicholas Konz

dblp:307/2984 · also Nick Konz · DBLP profile ↗
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12ranked-venue papers
5as first author
12since 2021 · last 2026
0000-0003-0230-1598ORCID · verified

Domains — the database's venue-derived domains; a paper can count in several

Applied, interdisciplinary, general and emerging computing · 8 · 4 first-author · 8 since 2021Graphics, computer vision, multimedia, augmented reality and games · 3 · 2 first-author · 3 since 2021Artificial intelligence and machine learning · 2 · 1 first-author · 2 since 2021Human-computer interaction and ubiquitous computing · 1 · 1 since 2021
YearPublicationVenuePosition
2026 Quantifying the Limits of Segmentation Foundation Models: Modeling Challenges in Segmenting Tree-Like and Low-Contrast Objects
abstract
Image segmentation foundation models (SFMs) like Segment Anything Model (SAM) have achieved impressive zero-shot and interactive segmentation across diverse domains. However, they struggle to segment objects with certain structures, particularly those with dense, tree-like morphology and low textural contrast from their surroundings. These failure modes are crucial for understanding the limitations of SFMs in real-world applications. To systematically study this issue, we introduce interpretable metrics quantifying object tree-likeness and textural separability. On carefully controlled synthetic experiments and real-world datasets, we show that SFM performance (e.g., SAM, SAM 2, HQ-SAM) noticeably correlates with these factors. We attribute these failures to SFMs misinterpreting local structure as global texture, resulting in over-segmentation or difficulty distinguishing objects from similar backgrounds. Notably, targeted fine-tuning fails to resolve this issue, indicating a fundamental limitation. Our study provides the first quantitative framework for modeling the behavior of SFMs on challenging structures, offering interpretable insights into their segmentation capabilities.1
Nicholas Konz, Kevin Kramer, Maciej A. Mazurowski
WACV2
2026 Fréchet radiomic distance (FRD): A versatile metric for comparing medical imaging datasets
Nicholas Konz, Richard Osuala, Preeti Verma, Yuwen Chen 0003, Hanxue Gu, Haoyu Dong 0003, Yaqian Chen, Andrew Marshall, Lidia Garrucho, Kaisar Kushibar, Daniel Lang 0003, Sungheon Gene Kim, Lars J. Grimm, John Lewin, James S. Duncan, Julia A. Schnabel, Oliver Díaz, Karim Lekadir, Maciej A. Mazurowski
Medical Image Anal.1
2026 GuidedMorph: Two-Stage Deformable Registration for Breast MRI
abstract
Accurately registering breast MR images from different time points enables the alignment of anatomical structures and tracking of tumor progression, supporting more effective breast cancer detection, diagnosis, and treatment planning. However, the complexity of dense tissue and its highly non-rigid nature pose challenges for conventional registration methods, which primarily focus on aligning general structures while overlooking intricate internal details. To address this, we propose GuidedMorph, a novel two-stage registration framework designed to better align dense tissue. In addition to a single-scale network for global structure alignment, we introduce a framework that utilizes dense tissue information to track breast movement. The learned transformation fields are fused by introducing the Dual Spatial Transformer Network (DSTN), improving overall alignment accuracy. A novel warping method based on the Euclidean distance transform (EDT) is also proposed to accurately warp the registered dense tissue and breast masks, preserving fine structural details during deformation. It also operates effectively with the VoxelMorph and TransMorph backbones, offering a versatile solution for breast registration. We validate our method on ISPY2 and internal dataset, demonstrating superior performance in dense tissue, overall breast alignment, and breast structural similarity index measure (SSIM), with notable improvements by over 20.9% in dense tissue Dice, 2.1% in breast Dice, and 3.5% in breast SSIM compared to the best baseline.
Yaqian Chen, Hanxue Gu, Haoyu Dong 0003, Qihang Li, Yuwen Chen 0003, Nicholas Konz, Lin Li 0092, Maciej A. Mazurowski
IEEE J. Biomed. Health Informatics6
2026 Accelerating Volumetric Medical Image Annotation via Short-Long Memory SAM 2
abstract
Manual annotation of volumetric medical images, such as magnetic resonance imaging (MRI) and computed tomography (CT), is a labor-intensive and time-consuming process. Recent advancements in foundation models for video object segmentation, such as Segment Anything Model 2 (SAM 2), offer a potential opportunity to significantly speed up the annotation process by manually annotating one or a few slices and then propagating target masks across the entire volume. However, the performance of SAM 2 in this context varies. Our experiments show that relying on a single memory bank and attention module is prone to error propagation, particularly at boundary regions where the target is present in the previous slice but absent in the current one. To address this problem, we propose Short-Long Memory SAM 2 (SLM-SAM 2), a novel architecture that integrates distinct short-term and long-term memory banks with separate attention modules to improve segmentation accuracy. We evaluate SLM-SAM 2 on four public datasets covering organs, bones, and muscles across MRI, CT, and ultrasound videos. We show that the proposed method markedly outperforms the default SAM 2, achieving an average Dice Similarity Coefficient improvement of 0.14 and 0.10 in the scenarios when 5 volumes and 1 volume are available for the initial adaptation, respectively. SLM-SAM 2 also exhibits stronger resistance to over-propagation, reducing the time required to correct propagated masks by 60.575% per volume compared to SAM 2, making a notable step toward more accurate automated annotation of medical images for segmentation model development.
Yuwen Chen 0003, Zafer Yildiz, Qihang Li, Yaqian Chen, Haoyu Dong 0003, Hanxue Gu, Nicholas Konz, Maciej A. Mazurowski
IEEE Trans. Medical Imaging7
2024 The Effect of Intrinsic Dataset Properties on Generalization: Unraveling Learning Differences Between Natural and Medical Images
abstract
This paper investigates discrepancies in how neural networks learn from different imaging domains, which are commonly overlooked when adopting computer vision techniques from the domain of natural images to other specialized domains such as medical images. Recent works have found that the generalization error of a trained network typically increases with the intrinsic dimension ($d_{data}$) of its training set. Yet, the steepness of this relationship varies significantly between medical (radiological) and natural imaging domains, with no existing theoretical explanation. We address this gap in knowledge by establishing and empirically validating a generalization scaling law with respect to $d_{data}$, and propose that the substantial scaling discrepancy between the two considered domains may be at least partially attributed to the higher intrinsic ``label sharpness'' ($K_\mathcal{F}$) of medical imaging datasets, a metric which we propose. Next, we demonstrate an additional benefit of measuring the label sharpness of a training set: it is negatively correlated with the trained model's adversarial robustness, which notably leads to models for medical images having a substantially higher vulnerability to adversarial attack. Finally, we extend our $d_{data}$ formalism to the related metric of learned representation intrinsic dimension ($d_{repr}$), derive a generalization scaling law with respect to $d_{repr}$, and show that $d_{data}$ serves as an upper bound for $d_{repr}$. Our theoretical results are supported by thorough experiments with six models and eleven natural and medical imaging datasets over a range of training set sizes. Our findings offer insights into the influence of intrinsic dataset properties on generalization, representation learning, and robustness in deep neural networks. *Code link: https://github.com/mazurowski-lab/intrinsic-properties*
Nicholas Konz, Maciej A. Mazurowski
ICLR1
2024 Anatomically-Controllable Medical Image Generation with Segmentation-Guided Diffusion Models
Nicholas Konz, Yuwen Chen 0003, Haoyu Dong 0003, Maciej A. Mazurowski
MICCAI (7)1
2023 Understanding the Inner-workings of Language Models Through Representation Dissimilarity
abstract
As language models are applied to an increasing number of real-world applications, understanding their inner workings has become an important issue in model trust, interpretability, and transparency.In this work we show that representation dissimilarity measures, which are functions that measure the extent to which two model's internal representations differ, can be a valuable tool for gaining insight into the mechanics of language models.Among our insights are: (i) an apparent asymmetry in the internal representations of model using SoLU and GeLU activation functions, (ii) evidence that dissimilarity measures can identify and locate generalization properties of models that are invisible via in-distribution test set performance, and (iii) new evaluations of how language model features vary as width and depth are increased.Our results suggest that dissimilarity measures are a promising set of tools for shedding light on the inner workings of language models.
Davis Brown, Charles Godfrey, Nicholas Konz, Jonathan H. Tu, Henry Kvinge
EMNLP3
2023 Unsupervised anomaly localization in high-resolution breast scans using deep pluralistic image completion
Nicholas Konz, Haoyu Dong 0003, Maciej A. Mazurowski
Medical Image Anal.1
2023 Segment anything model for medical image analysis: An experimental study
Maciej A. Mazurowski, Haoyu Dong 0003, Hanxue Gu, Nicholas Konz
Medical Image Anal.5
2023 SWSSL: Sliding Window-Based Self-Supervised Learning for Anomaly Detection in High-Resolution Images
abstract
Anomaly detection (AD) aims to determine if an instance has properties different from those seen in normal cases. The success of this technique depends on how well a neural network learns from normal instances. We observe that the learning difficulty scales exponentially with the input resolution, making it infeasible to apply AD to high-resolution images. Resizing them to a lower resolution is a compromising solution and does not align with clinical practice where the diagnosis could depend on image details. In this work, we propose to train the network and perform inference at the patch level, through the sliding window algorithm. This simple operation allows the network to receive high-resolution images but introduces additional training difficulties, including inconsistent image structure and higher variance. We address these concerns by setting the network's objective to learn augmentation-invariant features. We further study the augmentation function in the context of medical imaging. In particular, we observe that the resizing operation, a key augmentation in general computer vision literature, is detrimental to detection accuracy, and the inverting operation can be beneficial. We also propose a new module that encourages the network to learn from adjacent patches to boost detection performance. Extensive experiments are conducted on breast tomosynthesis and chest X-ray datasets and our method improves 8.03% and 5.66% AUC on image-level classification respectively over the current leading techniques. The experimental results demonstrate the effectiveness of our approach.
Haoyu Dong 0003, Yifan Zhang 0013, Hanxue Gu, Nicholas Konz, Maciej A. Mazurowski
IEEE Trans. Medical Imaging4
2023 Computer Vision Techniques in Manufacturing
abstract
Computer vision (CV) techniques have played an important role in promoting the informatization, digitization, and intelligence of industrial manufacturing systems. Considering the rapid development of CV techniques, we present a comprehensive review of the state of the art of these techniques and their applications in manufacturing industries. We survey the most common methods, including feature detection, recognition, segmentation, and three-dimensional modeling. A system framework of CV in the manufacturing environment is proposed, consisting of a lighting module, a manufacturing system, a sensing module, CV algorithms, a decision-making module, and an actuator. Applications of CV to different stages of the entire product life cycle are then explored, including product design, modeling and simulation, planning and scheduling, the production process, inspection and quality control, assembly, transportation, and disassembly. Challenges include algorithm implementation, data preprocessing, data labeling, and benchmarks. Future directions include building benchmarks, developing methods for nonannotated data processing, developing effective data preprocessing mechanisms, customizing CV models, and opportunities aroused by 5G.
Longfei Zhou, Lin Zhang 0009, Nicholas Konz
IEEE Trans. Syst. Man Cybern. Syst.3
2022 The Intrinsic Manifolds of Radiological Images and Their Role in Deep Learning
Nicholas Konz, Hanxue Gu, Haoyu Dong 0003, Maciej A. Mazurowski
MICCAI (8)1