Computing Null Space Hallucinations on Simulated SPECT Image Reconstructions

Nau M, Reymann M, Massanes F, Vija AH, Maier A (2023)

Publication Language: English

Publication Type: Conference contribution, Abstract of a poster

Publication year: 2023

Event location: Vancouver, BC, Canada CA

ISBN: 979-8-3503-3866-9

URI: https://ieeexplore.ieee.org/abstract/document/10338608

DOI: 10.1109/NSSMICRTSD49126.2023.10338608

Abstract

Iterative reconstruction techniques have been integrated into clinical practice for emission tomography reconstruction. While these techniques have shown promising results in image reconstruction, there remains a lack of clarity regarding which parts of the image are reliably estimated and which are not. Currently, there is a missing measure to differentiate between epistemic and aleatoric errors. One approach to address this issue is to estimate the null space of the imaging model for a given object. In this study, we utilize a previously proposed adaptation of the Landweber iteration, known as the Wilson-Barret method, for calculating the null space of a noiseless reference phantom and for a corresponding reconstruction of a simulated phantom. Using the calculated null spaces we can apply a method for creating hallucination maps, that allow derivation of the epistemic error. Our findings suggest that the hallucinated components of the image are primarily attributable to the edges or high-frequency components of the phantom as well as the center of the phantom, which is consistent with expectations.

Authors with CRIS profile

Merlin Nau Lehrstuhl für Informatik 5 (Mustererkennung) Maximilian Reymann Lehrstuhl für Informatik 5 (Mustererkennung) Andreas Maier Lehrstuhl für Informatik 5 (Mustererkennung)

Involved external institutions

Siemens AG, Healthcare Sector DE Germany (DE)

How to cite

APA:

Nau, M., Reymann, M., Massanes, F., Vija, A.H., & Maier, A. (2023, December). Computing Null Space Hallucinations on Simulated SPECT Image Reconstructions. Poster presentation at 2023 IEEE Nuclear Science Symposium, Medical Imaging Conference and International Symposium on Room-Temperature Semiconductor Detectors (NSS MIC RTSD), Vancouver, BC, Canada, CA.

MLA:

Nau, Merlin, et al. "Computing Null Space Hallucinations on Simulated SPECT Image Reconstructions." Presented at 2023 IEEE Nuclear Science Symposium, Medical Imaging Conference and International Symposium on Room-Temperature Semiconductor Detectors (NSS MIC RTSD), Vancouver, BC, Canada Ed. IEEE, 2023.

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