Exact and Calibrated Diffusion Reconstruction for Digital Breast Tomosynthesis
- URL: http://arxiv.org/abs/2607.12937v1
- Date: Tue, 14 Jul 2026 16:10:10 GMT
- Title: Exact and Calibrated Diffusion Reconstruction for Digital Breast Tomosynthesis
- Abstract summary: Limited-angle digital breast tomosynthesis (DBT) reconstructs a volume from a few low-dose projections over a narrow arc.<n> Conditional diffusion priors achieve strong perceptual quality here but leave three clinical obstacles: inexact data consistency, unlocalized hallucination, and uncalibrated uncertainty.<n>This is the first data-consistent, uncertainty-calibrated learned reconstruction for limited-angle reconstruction.
- Score: 0.0
- License: http://creativecommons.org/licenses/by-nc-sa/4.0/
- Abstract: Limited-angle digital breast tomosynthesis (DBT) reconstructs a volume from a few low-dose projections over a narrow arc. At a representative nine-view, $25^{\circ}$ protocol more than 98% of image space is unmeasured, so a learned prior must supply structure in the missing wedge. Conditional diffusion priors achieve strong perceptual quality here but leave three clinical obstacles: inexact data consistency, unlocalized hallucination, and uncalibrated uncertainty. We enforce measurements exactly by replacing the per-step proximal update of a conditional diffusion sampler with exact Euclidean projection onto the data-consistent set, computed via an $m$-dimensional dual system with a one-time Gram matrix $AA^{\top}$ factorization. This projection costs 4.5 ms per step (a $248\times$ speedup) and drives the data residual to the double-precision floor ($2.4\times10^{-13}$). We prove it is the $ρ\to0$ limit of the proximal step, provide a no-harm theorem, and show that exactly consistent sample ensembles have variance supported on null($A$). Thus, the mean's entire error lies in the unmeasured subspace covered by the uncertainty map. On patient-derived breast phantoms, this improves fidelity at no depth-resolution cost. Conversely, a proximal step applied post-update degrades quality, isolating the consistency step's placement as decisive. Isotonic recalibration brings the ensemble spread to a calibrated error scale (expected calibration error $0.029\to0.008$; standardized error $4.7\to0.96$), ranking errors better than the pure prior. We also repair a 20.3% adjoint mismatch in a deployed projector via a materialized operator of record. This is the first data-consistent, uncertainty-calibrated learned reconstruction for limited-angle DBT. The solver naturally relaxes to discrepancy-ball and maximum-a-posteriori modes for noisy measurements.
Related papers
- Detecting and Discriminating Operator Misspecification in Hybrid PDE-Parameter Learning: a Reference-Free Instrument, with Discrimination Bounded In Sample [0.0]
We build an instrument that reads from a single fit and with no oracle.<n>We report where the instrument is blind, a pre-registered negative where a neural estimator loses to Tikhonov-regularized inversion at recovery.
arXiv Detail & Related papers (2026-08-04T21:20:44Z) - Round-Trip Consistency: Bidirectional Diffusion Models Can Predict Their Own Rollout Errors [51.56484100374058]
Autoregressive models accumulate error over long rollouts, yet at deployment there is no ground truth to measure it against.<n>We train a single conditional latent diffusion model that steps a dynamical system forward or backward in time via a direction flag.<n>We show that this bidirectionality supplies a measurement-free test-time error signal.
arXiv Detail & Related papers (2026-08-01T13:49:46Z) - Calibrated Closed-Form Uncertainty for Radiative Gaussian Splatting in Sparse-View CT [13.147279382369293]
We present the first systematic calibration study for Gaussian-splatting CT.<n>We show that the resulting per-voxel uncertainty ranks true reconstruction error on 14 of 15 scenes of the official benchmark.<n>We then dissect why uncalibrated acquisition scores can nevertheless select acceptable views.
arXiv Detail & Related papers (2026-07-15T10:25:05Z) - Fixed-Protocol Amortized MPS Tomography with Conformalized Predictive Uncertainty [31.082191748525137]
Quantum state tomography is sample-starved, and the states one prepares live on a narrow, learnable manifold.<n>A prior estimate is already near-optimal, so high fidelity at few measurements'' can be family memorization rather than tomography.<n>We propose a emph-protocol amortized MPS estimator trained once with a gauge-invariant fidelity loss.
arXiv Detail & Related papers (2026-07-13T08:57:23Z) - $\mathbfλ$-VAE: Variance Equalization for Posterior Collapse [0.0]
Variational Autoencoders (VAEs) frequently suffer from posterior collapse, a failure mode in which the approximate posterior converges to the prior.<n>We identify and formalize two logically independent but coupled causes.
arXiv Detail & Related papers (2026-07-06T18:07:46Z) - The Right Measure for Physics-Constrained Generation: A Co-Area Correction for Posterior-Consistent PDE Inverse Problems [28.97171921966014]
Generative models are increasingly used to solve partial differential equation (PDE) inverse problems.<n>We show that this widely adopted recipe samples the wrong distribution.<n>We introduce textbfCoCoS, a measure-aware constrained sampler that targets the correct co-area posterior.
arXiv Detail & Related papers (2026-06-03T12:30:03Z) - Bandit Convex Optimization with Gradient Prediction Adaptivity [56.816177049016794]
We investigate whether optimistic gradient predictions can improve worst-case regret guarantees in a prediction-adaptive manner.<n>The key idea is a novel variance-reduced gradient estimator whose variance scales with the prediction error rather than the gradient norm.<n>We establish an information-theoretic lower bound that scales as $(sqrtmathbbE[S_T])$, providing a fundamental characterization of the best achievable prediction-adaptive regret.
arXiv Detail & Related papers (2026-05-21T08:57:38Z) - Correction and Corruption: A Two-Rate View of Error Flow in LLM Protocols [51.56484100374058]
We propose a paired-outcome measurement interface for auditing a single protocol step on exact-match tasks.<n>For each instance, the interface records a baseline correctness bit and a post-step correctness bit.<n>These rates predict accuracy changes and define a reusable empirical interface testable across seeds, mixtures, and pipelines.
arXiv Detail & Related papers (2026-04-20T13:25:40Z) - Optimal Unconstrained Self-Distillation in Ridge Regression: Strict Improvements, Precise Asymptotics, and One-Shot Tuning [61.07540493350384]
Self-distillation (SD) is the process of retraining a student on a mixture of ground-truth and the teacher's own predictions.<n>We show that for any prediction risk, the optimally mixed student improves upon the ridge teacher for every regularization level.<n>We propose a consistent one-shot tuning method to estimate $star$ without grid search, sample splitting, or refitting.
arXiv Detail & Related papers (2026-02-19T17:21:15Z) - Orthogonal Causal Calibration [55.28164682911196]
We develop general algorithms for reducing the task of causal calibration to that of calibrating a standard (non-causal) predictive model.<n>Our results are exceedingly general, showing that essentially any existing calibration algorithm can be used in causal settings.
arXiv Detail & Related papers (2024-06-04T03:35:25Z) - On the Distance from Calibration in Sequential Prediction [4.14360329494344]
We study a sequential binary prediction setting where the forecaster is evaluated in terms of the calibration distance.
The calibration distance is a natural and intuitive measure of deviation from perfect calibration.
We prove that there is a forecasting algorithm that achieves an $O(sqrtT)$ calibration distance in expectation on an adversarially chosen sequence of $T$ binary outcomes.
arXiv Detail & Related papers (2024-02-12T07:37:19Z) - Analytic Signal Phase in $N-D$ by Linear Symmetry Tensor--fingerprint
modeling [69.35569554213679]
We show that the Analytic Signal phase, and its gradient have a hitherto unstudied discontinuity in $2-D $ and higher dimensions.
This shortcoming can result in severe artifacts whereas the problem does not exist in $1-D $ signals.
We suggest the use of Linear Symmetry phase, relying on more than one set of Gabor filters, but with a negligible computational add-on.
arXiv Detail & Related papers (2020-05-16T21:17:26Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.