Physics in medicine and biology最新文献

{"title":"HWA-ResMamba: automatic segmentation of coronary arteries based on residual Mamba with high-order wavelet-enhanced convolution and attention feature aggregation.","authors":"Jinzhong Yang, Peng Hong, Lu Wang, Lisheng Xu, Dongming Chen, Chengbao Peng, An Ping, Benqiang Yang","doi":"10.1088/1361-6560/adc0dd","DOIUrl":"https://doi.org/10.1088/1361-6560/adc0dd","url":null,"abstract":"<p><p>Automatic segmentation of coronary arteries is a crucial prerequisite in assisting in the diagnosis of coronary artery disease. However, due to the fuzzy boundaries, small-slender branches, and significant individual variations, automatic segmentation of coronary arteries is extremely challenging. To address these challenges, this study proposes a residual Mamba with high-order wavelet-enhanced convolution and attention feature aggregation (HWA-ResMamba). The network consists of three core modules: high-order wavelet-enhanced convolution block (HWCB), residual Mamba (ResMamba) module, and attention feature aggregation (AFA) module. Firstly, the HWCB captures low-frequency information of the image in the shallow layers of the network, allowing for detailed exploration of subtle changes in the boundaries of coronary arteries. Secondly, the ResMamba module establishes long-range dependencies between features in the deep layers of the encoder and at the beginning of the decoder, improving the continuity of the segmentation process. Finally, the&#xD;AFA module in the decoder reduces semantic differences between the encoder and decoder, which can capture small-slender coronary artery branches and further improve segmentation accuracy. Experiments on two coronary artery segmentation datasets have shown that the&#xD;HWA-ResMamba outperforms other state-of-the-art methods in terms of performance and generalization. Specifically, in the self-built dataset, HWA-ResMamba obtained Dice of&#xD;0.8857 and Hausdorff Distance (HD) of 1.9028, outperforming nnUnet by 0.0521, and 0.5489, respectively. HWA-ResMamba obtained Dice of 0.8371, and HD of 3.7205 in the public dataset, outperforming nnUnet by 0.0255, and 2.7533, respectively. These results demonstrate that the proposed model performs well in segmenting coronary arteries.&#xD.</p>","PeriodicalId":20185,"journal":{"name":"Physics in medicine and biology","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143630838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimizing<i>in vivo</i>data acquisition for robust clinical microvascular imaging using ultrasound localization microscopy.","authors":"Chengwu Huang, U-Wai Lok, Jingke Zhang, Xiang Yang Zhu, James D Krier, Amy Stern, Kate M Knoll, Kendra Petersen, Kathryn A Robinson, Gina K Hesley, Andrew J Bentall, Thomas D Atwell, Andrew D Rule, Lilach O Lerman, Shigao Chen","doi":"10.1088/1361-6560/adc0de","DOIUrl":"https://doi.org/10.1088/1361-6560/adc0de","url":null,"abstract":"<p><strong>Objective: </strong>Ultrasound localization microscopy (ULM) enables microvascular imaging at spatial resolutions beyond the acoustic diffraction limit, offering significant clinical potentials. However, ULM performance relies heavily on microbubble (MB) signal sparsity, the number of detected MBs, and signal-to-noise ratio (SNR), all of which vary in clinical scenarios involving bolus MB injections. These sources of variations underscore the need to optimize MB dosage, data acquisition timing, and imaging settings in order to standardize and optimize ULM of microvasculature. This pilot study aims to investigate the temporal changes in MB signals during bolus injections in both pig and human models to optimize data acquisition for clinical ULM.</p><p><strong>Approach: </strong>Quantitative indices, mainly including individual MB SNR, normalized cross-correlation (NCC) of the MB signal with the point-spread function (PSF), and the number of localizable MBs, were developed to evaluate MB signal quality and guide the selection of acquisition timing. The effects of transmitted voltage and dosage on signal quality for MB localization were also explored.</p><p><strong>Main results: </strong>In both pig and human studies, MB localization quality (primarily indicated by NCC) reached a minimum at peak MB concentration, then improved as MB counts decreased during the wash-out phase. An optimal acquisition window was identified by balancing localization quality (empirically, NCC > 0.57) and MB concentration. In the pig model, a relatively short time window (approximately 10 seconds) for optimal acquisition was identified during the rapid wash-out phase, highlighting the need for real-time MB signal monitoring during data acquisition. The slower wash-out phase in humans allowed for a more flexible imaging window of 1-2 minutes, while trade-offs were observed between localization quality and MB density (or acquisition length) at different wash-out phase timings. Guided by these findings, robust ULM imaging was achieved in both pig and human kidneys using a short period of data acquisition (3.6 s and 9.6 s of data), demonstrating its feasibility in clinical practice.</p><p><strong>Significance: </strong>This study provides insights into optimizing data acquisition for consistent and reproducible ULM, paving the way for its standardization and broader clinical applications.</p>","PeriodicalId":20185,"journal":{"name":"Physics in medicine and biology","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143630845","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Role of modeled high-grade glioma cell invasion and survival on the prediction of tumor progression after radiotherapy.","authors":"Wille Häger, Iuliana Toma-Dașu, Mehdi Astaraki, Marta Lazzeroni","doi":"10.1088/1361-6560/adbcf4","DOIUrl":"10.1088/1361-6560/adbcf4","url":null,"abstract":"<p><p><i>Objective.</i>Glioblastoma (GBM) prognosis remains poor despite progress in radiotherapy and imaging techniques. Tumor recurrence has been attributed to the widespread tumor invasion of normal tissue. Since the complete extension of invasion is undetectable on imaging, it is not deliberately treated. To improve the treatment outcome, models have been developed to predict tumor invasion based standard imaging data. This study aimed to investigate whether a tumor invasion model, together with the predicted number of surviving cells after radiotherapy, could predict tumor progression post-treatment.<i>Approach.</i>A tumor invasion model was applied to 56 cases of GBMs treated with radiotherapy. The invasion was quantified as the volume encompassed by the 100 cells mm^-3isocontour (<i>V</i>₁₀₀). A new metric, cell-volume-product, was defined as the product of the volume with cell density greater than a threshold value (in cells mm^-3), and the number of surviving cells within that volume, post-treatment. Tumor progression was assessed at 20 ± 10 d and 90 ± 20 d after treatment. Correlations between the disease progression and the gross tumor volume (GTV),<i>V</i>₁₀₀, and cell-volume-product, were determined using receiver operating characteristic curves.<i>Main results.</i>For the early follow-up time, the correlation between GTV and tumor progression was not statistically significant (<i>p</i>= 0.684). However, statistically significant correlations with progression were found between<i>V</i>₁₀₀and cell-volume-product with a cell threshold of 10^-6cells mm^-3with areas-under-the-curve of 0.69 (<i>p</i>= 0.023) and 0.66 (<i>p</i>= 0.045), respectively. No significant correlations were found for the late follow-up time.<i>Significance.</i>Modeling tumor spread otherwise undetectable on conventional imaging, as well as radiobiological model predictions of cell survival after treatment, may provide useful information regarding the likelihood of tumor progression at an early follow-up time point, which could potentially lead to improved treatment decisions for patients with GBMs.</p>","PeriodicalId":20185,"journal":{"name":"Physics in medicine and biology","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143567956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reference dosimetry for MRI-Linacs: an addendum to the 2020 IPEM code of practice for high-energy photon therapy dosimetry.","authors":"Ilias Billas, Geoff J Budgell, Ben George, Russell A S Thomas, Simon Duane, David J Eaton","doi":"10.1088/1361-6560/adc0e0","DOIUrl":"https://doi.org/10.1088/1361-6560/adc0e0","url":null,"abstract":"<p><p>The 2020 Institute of Physics and Engineering in Medicine code of practice (COP) for megavoltage dosimetry (Eaton et al 2020, Phys. Med. Biol. 65(19): 195006) provides standardised and practical methods for measurement of absorbed dose to water, linked to calibration by the National Physical Laboratory. This report extends the use of that COP to MRI-Linacs through the addition of two correction factors: (1) to account for the influence of the magnetic field on the absorbed dose and model-specific chamber response; and (2) to account for differences in chamber response in the beam spectrum of the MRI-Linac and the Linac where the cross-calibration is performed. Guidance is provided on practical aspects of chamber calibration and dose measurement in MRI-Linac beams, including the use of liquid water, consistent chamber orientation and corrections for other influence quantities. Using this approach uncertainties are similar to other applications of the COP.</p>","PeriodicalId":20185,"journal":{"name":"Physics in medicine and biology","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143630849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimisation of magnetic field sensing with optically pumped magnetometers for magnetic detection electrical impedance tomography.","authors":"Kai Mason, Florencia Maurino-Alperovich, Kirill Y Aristovich, David S Holder","doi":"10.1088/1361-6560/adc0df","DOIUrl":"https://doi.org/10.1088/1361-6560/adc0df","url":null,"abstract":"<p><strong>Objective: </strong>Magnetic Detection Electrical Impedance Tomography is a novel technique that could enable non-invasive imaging of fast neural activity in the brain. However, commercial magnetometers are not suited to its technical requirements. The purpose of this work was to optimise the number, orientation and size of optically pumped magnetometers for MDEIT and inform the future development of MDEIT-specific magnetometers.</p><p><strong>Approach: </strong>Computational modelling was used to perform forward and inverse MDEIT modelling. Images were reconstructed using three sensing axes, arrays of 16 to 160 magnetometers, and cell sizes ranging from 1 to 18 mm. Image quality was evaluated visually and with the weighted spatial variance.</p><p><strong>Main results: </strong>Single-axis measurements normal to the surface provided the best image quality, and image quality increased with an increase in sensor number and size. The optimal sensing arrangement balancing image quality and practical implementation was measurement normal to the surface of the scalp using between 48 and 96 magnetometers with a cubic cell with an 18 mm side length.</p><p><strong>Significance: </strong>This study can inform future OPM design, showing the size of the vapour cell need not be constrained to that of commercially available OPMs, and that the development of a small array of single-axis, highly sensitive, high-bandwidth OPMs should be prioritised for fast neural MDEIT.</p>","PeriodicalId":20185,"journal":{"name":"Physics in medicine and biology","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143630840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Model observers and detectability index in x-ray imaging: historical review, applications and future trends.","authors":"Elsa Bifano Pimenta, Paulo Roberto R Costa","doi":"10.1088/1361-6560/adc070","DOIUrl":"https://doi.org/10.1088/1361-6560/adc070","url":null,"abstract":"<p><p>The detectability index, originally developed in psychophysics, has been applied in medical imaging to integrate objective metrics with subjective assessments. This index accounts for both image processing properties and the limitations of the human visual system, thus enhancing the clinical efficacy of imaging technologies. By providing a single metric that captures multiple aspects of image quality, the detectability index offers a comprehensive evaluation of clinical images. Numerous applications of this index across various areas of medical imaging are documented in the literature, along with recommendations for its use in periodic performance evaluations of imaging devices. However, since different modalities of images may require different detectability indices, it is crucial to assess the adequacy of the properties of the image being analyzed and those from the adopted index. A thorough understanding of this metric, including its statistical nature and complex relationship with model observers, is essential to ensure its proper application and interpretation, and to prevent misuse. Medical physicists face the challenge of a lack of organized guidance on the detectability index, necessitating a comprehensive review of its merits and drawbacks. This paper aims to trace the origins, concepts, and clinical applications of the detectability index, offering insight into its strengths, limitations, and future potential. To achieve this, an extensive literature review was conducted, covering the evolution of the index from its early use in radar interpretation to its current applications in modern imaging techniques and future trends. The paper includes supplementary materials such as a compendium of fundamental concepts, ancillary information, and mathematical deductions to help readers less experienced in the subject.</p>","PeriodicalId":20185,"journal":{"name":"Physics in medicine and biology","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143625265","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development and dosimetric evaluation of a modulated intraoperative radiotherapy (mIORT) system using the Zeiss intrabeam device.","authors":"Xavier Jones, Gabor Neveri, Marsha Chin, Pejman Rowshanfarzad","doi":"10.1088/1361-6560/adc06f","DOIUrl":"https://doi.org/10.1088/1361-6560/adc06f","url":null,"abstract":"<p><p>Objective&#xD;Intraoperative radiotherapy (IORT) is a specialised radiotherapy technique that delivers a precise, single high-dose fraction to the tumour bed after surgical removal of the tumour, aiming to eliminate residual cancer cells. This study investigates the incorporation of novel applicators into an existing intraoperative radiotherapy (IORT) system to enable dose modulation, performing Monte Carlo simulations, 3D printing, and experimental validation. The Zeiss Intrabeam IORT device, a low-kV IORT system capable of delivering X-rays nearly isotropically, with energies up to 50 kV, was used in this study. &#xD;Approach&#xD;Applicators were modified to alter dose distributions, incorporating features such as shielding or changes to an ellipsoid shape. The EGSnrc Monte Carlo (MC) code was employed to simulate the dose distributions of each applicator design, generating data such as dose maps, percentage depth dose (PDD) curves, percent difference maps between shielded and unshielded regions, and energy spectra to characterise each applicator. Gafchromic EBT3 film measurements were performed on select 3D printed applicators, to verify the MC simulations, with dose distribution data extracted for comparison. &#xD;Main Results&#xD;Visual comparisons of dose and percentage different maps indicate a high correlation between the MC simulations and film measurements. Most PDD points for spherical applicators showed deviations within 4%, while ellipsoid applicators had deviations of 14% for the unshielded and 5% for the shielded applicators. All RMSEs were below 0.05 for spherical and 0.18 for ellipsoid designs. Based on film data, shielded ellipsoid applicators reduced the dose by ~99%, 48%, 22%, and 8% at 0.3, 1, 2, and 3 cm, respectively, while shielded spherical applicators achieved ~83%, 35%, 14%, and 7% reductions at the same distances. Energy spectra for photons exiting shielded regions were also generated. &#xD;Significance&#xD;Results of this study may be used in the development of patient-specific IORT techniques, or the development of a treatment planning system involving mIORT. &#xD.</p>","PeriodicalId":20185,"journal":{"name":"Physics in medicine and biology","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143625260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"3D<i>π</i>: three-dimensional positron imaging, a novel total-body PET scanner using xenon-doped liquid argon scintillator.","authors":"Azam Zabihi, Xinran Li, Alejandro Ramirez, Iftikhar Ahmad, Manuel D Da Rocha Rolo, Davide Franco, Federico Gabriele, Cristiano Galbiati, Michela Lai, Daniel R Marlow, Andrew Renshaw, Shawn Westerdale, Masayuki Wada","doi":"10.1088/1361-6560/adbaac","DOIUrl":"10.1088/1361-6560/adbaac","url":null,"abstract":"<p><p><i>Objective.</i>This paper introduces a novel PET imaging methodology called 3-dimensional positron imaging (3D<i>π</i>), which integrates total-body coverage, time-of-flight (TOF) technology, ultra-low dose imaging capabilities, and ultra-fast readout electronics inspired by emerging technology from the DarkSide collaboration.<i>Approach.</i>The study evaluates the performance of 3D<i>π</i>using Monte Carlo simulations based on NEMA NU 2-2018 protocols. The methodology employs a homogenous, monolithic scintillator composed of liquid argon (LAr) doped with xenon (Xe) with silicon photomultipliers (SiPMs) operating at cryogenic temperatures.<i>Main results.</i>Substantial improvements in system performance are observed, with the 3D<i>π</i>system achieving a noise equivalent count rate of 3.2 Mcps at 17.3 kBq ml^-1, continuing to increase up to 4.3 Mcps at 40 kBq ml^-1. Spatial resolution measurements show an average FWHM of 2.7 mm across both axial positions. The system exhibits superior sensitivity, with values reaching 373 kcps MBq^-1with a line source at the center of the field of view. Additionally, 3D<i>π</i>achieves a TOF resolution of 151 ps at 5.3 kBq ml^-1, highlighting its potential to produce high-quality images with reduced noise levels.<i>Significance.</i>The study underscores the potential of 3D<i>π</i>in improving PET imaging performance, offering the potential for shorter scan times and reduced radiation exposure for patients. The Xe-doped LAr offers advantages such as fast scintillation, enhanced light yield, and cost-effectiveness. Future research will focus on optimizing system geometry and further refining reconstruction algorithms to exploit the strengths of 3D<i>π</i>for clinical applications.</p>","PeriodicalId":20185,"journal":{"name":"Physics in medicine and biology","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143516494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Regularized origin ensemble with a beam prior for range verification in particle therapy with Compton-camera data.","authors":"Jona Kasprzak, Jorge Roser, Julius Friedemann Werner, Nadja Kohlhase, Andreas Bolke, Lisa-Marie Kaufmann, Magdalena Rafecas","doi":"10.1088/1361-6560/adbfd8","DOIUrl":"https://doi.org/10.1088/1361-6560/adbfd8","url":null,"abstract":"<p><strong>Objective: </strong>In particle therapy (PT), several methods are being investigated to help reduce range margins and identify deviations from the original treatment plan, such as prompt-gamma (PG) imaging with Compton cameras (CC). To reconstruct the images, the Origin Ensemble (OE) algorithm is commonly used. In the context of PT, artifacts and strong noise often affect CC images. To improve the ability of OE to identify range shifts, and also to enhance image quality, we propose to regularize OE using beam a-priori knowledge (beam prior).&#xD;Approach: We implemented the beam prior to OE using the class of Gibbs' distribution functions. For evaluation, Monte-Carlo simulations of centered and off-center beams with therapeutic energies impinging on a PMMA target were conducted in GATE. To introduce range shifts, air layers were introduced into the target. In addition, the effect of a bone layer, closer to a realistic scenario, was investigated. OE with the beam prior (BP-OE) and conventional OE (reference) were compared using the spill-over-ratio (SOR) as well as shifts in the distal falloff in projections using cubic splines with Chebyshev nodes.&#xD;Main results: BP-OE improved the shift estimates by up to 11% compared to conventional OE for centered and up to 250% with off-centered beams. BP-OE&#xD;decreased the image noise level, improving the SOR significantly by up to 96%.&#xD;Significance: BP-OE applied to CC data can improve shift estimations compared to conventional OE. The developed Gibbs-based regularization framework also allows&#xD;further prior functions to be included into OE, for instance, smoothing or edge-preserving priors. BP-OE could be extended to PET-based range verification or multiple-beam scenarios.</p>","PeriodicalId":20185,"journal":{"name":"Physics in medicine and biology","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143616773","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ultra-high energy spectral prompt PET.","authors":"Satyajit Ghosh, Valerio Cosmi, Ruud M Ramakers, Freek J Beekman, Marlies C Goorden","doi":"10.1088/1361-6560/adbfd7","DOIUrl":"https://doi.org/10.1088/1361-6560/adbfd7","url":null,"abstract":"<p><strong>Objective: </strong>Utilizing prompt gammas in preclinical pinhole-collimated PET avoids image degradation due to positron range blurring and photon down scatter, enables multi-isotope PET and can improve counting statistics for low-abundance positron emitters. This was earlier reported for 124I, 89Zr and simultaneous 124I -18F PET using the VECTor scanner (MILabs, The Netherlands), demonstrating sub-mm resolution despite long positron ranges. The aim of the present study is to investigate if such sub-mm PET imaging is also feasible for a large variety of other isotopes including those with extremely high energy prompt gammas (>1 MeV) or with complex emission spectra of prompt gammas.</p><p><strong>Approach: </strong>We use Monte Carlo simulations to assess achievable image resolutions and uniformity across a broad range of spectrum types and emitted prompt gamma energies (603 keV - 2.2 MeV), using 52Mn, 94Tc, 89Zr, 44Sc, 86Y, 72As, 124I, 38K, and 66Ga.</p><p><strong>Main results: </strong>Our results indicate that sub-millimeter resolution imaging may be feasible for almost all isotopes investigated, with the currently used cluster pinhole collimators. At prompt gamma energies of 603 keV of 124I, an image resolution of ~0.65 mm was achieved, while for emissions at 703, 744, 834, and 909 keV of 94Tc, 52Mn, 72As, and 89Zr, respectively, ~0.7 mm resolution was obtained. Finally, at ultra-high energies of 1.2 (44Sc) and 1.4 MeV (52Mn) resolutions of ~0.75 mm and ~0.8 mm could still be achieved although ring artifacts were observed at the highest energies (1.4 MeV). For 38K (2.2 MeV), an image resolution of 1.2 mm was achieved utilizing its 2.2 MeV prompt emission.</p><p><strong>Significance: </strong>This work shows that current cluster pinhole collimators are suitable for sub-mm resolution prompt PET up till at least 1.4 MeV. This may open up new avenues to developing new tracer applications and therapies utilizing these PET isotopes.</p>","PeriodicalId":20185,"journal":{"name":"Physics in medicine and biology","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143616775","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}