1
|
Syed MBJ, Fletcher AJ, Debono S, Forsythe RO, Williams MC, Dweck MR, Shah ASV, Macaskill MG, Tavares A, Denvir MA, Lim K, Wallace WA, Kaczynski J, Clark T, Sellers SL, Masson N, Falah O, Chalmers RTA, Tambyraja AL, van Beek EJR, Newby DE. 18F-Sodium Fluoride Positron Emission Tomography and Computed Tomography in Acute Aortic Syndrome. JACC Cardiovasc Imaging 2022; 15:1291-1304. [PMID: 35798405 DOI: 10.1016/j.jcmg.2022.01.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 01/01/2022] [Accepted: 01/07/2022] [Indexed: 12/11/2022]
Abstract
BACKGROUND Acute aortic syndrome is associated with aortic medial degeneration. 18F-sodium fluoride (18F-NaF) positron emission tomography (PET) detects microscopic tissue calcification as a marker of disease activity. OBJECTIVES In a proof-of-concept study, this investigation aimed to establish whether 18F-NaF PET combined with computed tomography (CT) angiography could identify aortic medial disease activity in patients with acute aortic syndrome. METHODS Patients with aortic dissection or intramural hematomas and control subjects underwent 18F-NaF PET/CT angiography of the aorta. Aortic 18F-NaF uptake was measured at the most diseased segment, and the maximum value was corrected for background blood pool activity (maximum tissue-to-background ratio [TBRmax]). Radiotracer uptake was compared with change in aortic size and major adverse aortic events (aortic rupture, aorta-related death, or aortic repair) over 45 ± 13 months. RESULTS Aortic 18F-NaF uptake co-localized with histologically defined regions of microcalcification and elastin disruption. Compared with control subjects, patients with acute aortic syndrome had increased 18F-NaF uptake (TBRmax: 1.36 ± 0.39 [n = 20] vs 2.02 ± 0.42 [n = 47] respectively; P < 0.001) with enhanced uptake at the site of intimal disruption (+27.5%; P < 0.001). 18F-NaF uptake in the false lumen was associated with aortic growth (+7.1 mm/year; P = 0.011), and uptake in the outer aortic wall was associated with major adverse aortic events (HR: 8.5 [95% CI: 1.4-50.4]; P = 0.019). CONCLUSIONS In patients with acute aortic syndrome, 18F-NaF uptake was enhanced at sites of disease activity and was associated with aortic growth and clinical events. 18F-NaF PET/CT holds promise as a noninvasive marker of disease severity and future risk in patients with acute aortic syndrome. (18F Sodium Fluoride PET/CT in Acute Aortic Syndrome [FAASt]; NCT03647566).
Collapse
Affiliation(s)
- Maaz B J Syed
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom.
| | - Alexander J Fletcher
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Samuel Debono
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Rachel O Forsythe
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Michelle C Williams
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Marc R Dweck
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Anoop S V Shah
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Mark G Macaskill
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Adriana Tavares
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Martin A Denvir
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Kelvin Lim
- Department of Cardiothoracic Surgery, Royal Infirmary of Edinburgh, NHS Lothian, Edinburgh, United Kingdom
| | - William A Wallace
- Department of Pathology, University of Edinburgh, Edinburgh, United Kingdom
| | - Jakub Kaczynski
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Tim Clark
- Edinburgh Imaging, Queens Medical Research Institute, University of Edinburgh. Edinburgh, United Kingdom
| | - Stephanie L Sellers
- Centre for Heart Lung Innovation, St Paul's Hospital and University of British Columbia, Vancouver, British Colombia, Canada
| | - Neil Masson
- Department of Radiology, Royal Infirmary of Edinburgh, NHS Lothian, Edinburgh, United Kingdom
| | - Orwa Falah
- The Edinburgh Vascular Service, Royal Infirmary of Edinburgh, NHS Lothian, Edinburgh, United Kingdom
| | - Roderick T A Chalmers
- The Edinburgh Vascular Service, Royal Infirmary of Edinburgh, NHS Lothian, Edinburgh, United Kingdom
| | - Andrew L Tambyraja
- The Edinburgh Vascular Service, Royal Infirmary of Edinburgh, NHS Lothian, Edinburgh, United Kingdom
| | - Edwin J R van Beek
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom; Edinburgh Imaging, Queens Medical Research Institute, University of Edinburgh. Edinburgh, United Kingdom
| | - David E Newby
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| |
Collapse
|
2
|
Debono S, Nash J, Fletcher AJ, Syed MBJ, Semple SI, van Beek EJR, Fletcher A, Cadet S, Williams MC, Dey D, Slomka PJ, Forsythe RO, Dweck MR, Newby DE. Quantifying sodium [ 18F]fluoride uptake in abdominal aortic aneurysms. EJNMMI Res 2022; 12:33. [PMID: 35666397 PMCID: PMC9170850 DOI: 10.1186/s13550-022-00904-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 05/25/2022] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Aortic microcalcification activity is a recently described method of measuring aortic sodium [18F]fluoride uptake in the thoracic aorta on positron emission tomography. In this study, we aimed to compare and to modify this method for use within the infrarenal aorta of patients with abdominal aortic aneurysms. METHODS Twenty-five patients with abdominal aortic aneurysms underwent an sodium [18F]fluoride positron emission tomography and computed tomography scan. Maximum and mean tissue-to-background ratios (TBR) and abdominal aortic microcalcification activity were determined following application of a thresholding and variable radius method to correct for vertebral sodium [18F]fluoride signal spill-over and the nonlinear changes in aortic diameter, respectively. Agreement between the methods, and repeatability of these approaches were assessed. RESULTS The aortic microcalcification activity method was much quicker to perform than the TBR method (14 versus 40 min, p < 0.001). There was moderate-to-good agreement between TBR and aortic microcalcification activity measurements for maximum (interclass correlation co-efficient, 0.67) and mean (interclass correlation co-efficient, 0.88) values. These correlations sequentially improved with the application of thresholding (intraclass correlation coefficient 0.93, 95% confidence interval 0.89-0.95) and variable diameter (intraclass correlation coefficient 0.97, 95% confidence interval 0.94-0.99) techniques. The optimised method had good intra-observer (mean 1.57 ± 0.42, bias 0.08, co-efficient of repeatability 0.36 and limits of agreement - 0.43 to 0.43) and inter-observer (mean 1.57 ± 0.42, bias 0.08, co-efficient of repeatability 0.47 and limits of agreement - 0.53 to 0.53) repeatability. CONCLUSIONS Aortic microcalcification activity is a quick and simple method which demonstrates good intra-observer and inter-observer repeatabilities and provides measures of sodium [18F]fluoride uptake that are comparable to established methods.
Collapse
Affiliation(s)
- Samuel Debono
- The University of Edinburgh Centre for Cardiovascular Science, Chancellor's Building, University of Edinburgh, 49 Little France Crescent, Edinburgh, EH16 4SB, UK.
| | - Jennifer Nash
- The University of Edinburgh Centre for Cardiovascular Science, Chancellor's Building, University of Edinburgh, 49 Little France Crescent, Edinburgh, EH16 4SB, UK
| | - Alexander J Fletcher
- The University of Edinburgh Centre for Cardiovascular Science, Chancellor's Building, University of Edinburgh, 49 Little France Crescent, Edinburgh, EH16 4SB, UK
| | - Maaz B J Syed
- The University of Edinburgh Centre for Cardiovascular Science, Chancellor's Building, University of Edinburgh, 49 Little France Crescent, Edinburgh, EH16 4SB, UK
| | - Scott I Semple
- The University of Edinburgh Centre for Cardiovascular Science, Chancellor's Building, University of Edinburgh, 49 Little France Crescent, Edinburgh, EH16 4SB, UK
| | - Edwin J R van Beek
- The University of Edinburgh Centre for Cardiovascular Science, Chancellor's Building, University of Edinburgh, 49 Little France Crescent, Edinburgh, EH16 4SB, UK
- Edinburgh Imaging Facility, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, UK
| | - Alison Fletcher
- Edinburgh Imaging Facility, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, UK
| | - Sebastien Cadet
- Division of Artificial Intelligence, Department of Medicine, Cedars-Sinai Medical Centre, Biomedical Imaging Research Institute, Los Angeles, USA
| | - Michelle C Williams
- The University of Edinburgh Centre for Cardiovascular Science, Chancellor's Building, University of Edinburgh, 49 Little France Crescent, Edinburgh, EH16 4SB, UK
| | - Damini Dey
- Division of Artificial Intelligence, Department of Medicine, Cedars-Sinai Medical Centre, Biomedical Imaging Research Institute, Los Angeles, USA
| | - Piotr J Slomka
- Division of Artificial Intelligence, Department of Medicine, Cedars-Sinai Medical Centre, Biomedical Imaging Research Institute, Los Angeles, USA
| | - Rachael O Forsythe
- The University of Edinburgh Centre for Cardiovascular Science, Chancellor's Building, University of Edinburgh, 49 Little France Crescent, Edinburgh, EH16 4SB, UK
| | - Marc R Dweck
- The University of Edinburgh Centre for Cardiovascular Science, Chancellor's Building, University of Edinburgh, 49 Little France Crescent, Edinburgh, EH16 4SB, UK
| | - David E Newby
- The University of Edinburgh Centre for Cardiovascular Science, Chancellor's Building, University of Edinburgh, 49 Little France Crescent, Edinburgh, EH16 4SB, UK
| |
Collapse
|
3
|
Akerele MI, Mushari NA, Forsythe RO, Syed M, Karakatsanis NA, Newby DE, Dweck MR, Tsoumpas C. Assessment of different quantification metrics of [ 18F]-NaF PET/CT images of patients with abdominal aortic aneurysm. J Nucl Cardiol 2022; 29:251-261. [PMID: 32557152 PMCID: PMC8873073 DOI: 10.1007/s12350-020-02220-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Accepted: 05/26/2020] [Indexed: 01/22/2023]
Abstract
BACKGROUND We aim to assess the spill-in effect and the benefit in quantitative accuracy for [18F]-NaF PET/CT imaging of abdominal aortic aneurysms (AAA) using the background correction (BC) technique. METHODS Seventy-two datasets of patients diagnosed with AAA were reconstructed with ordered subset expectation maximization algorithm incorporating point spread function (PSF). Spill-in effect was investigated for the entire aneurysm (AAA), and part of the aneurysm excluding the region close to the bone (AAAexc). Quantifications of PSF and PSF+BC images using different thresholds (% of max. SUV in target regions-of-interest) to derive target-to-background (TBR) values (TBRmax, TBR90, TBR70 and TBR50) were compared at 3 and 10 iterations. RESULTS TBR differences were observed between AAA and AAAexc due to spill-in effect from the bone into the aneurysm. TBRmax showed the highest sensitivity to the spill-in effect while TBR50 showed the least. The spill-in effect was reduced at 10 iterations compared to 3 iterations, but at the expense of reduced contrast-to-noise ratio (CNR). TBR50 yielded the best trade-off between increased CNR and reduced spill-in effect. PSF+BC method reduced TBR sensitivity to spill-in effect, especially at 3 iterations, compared to PSF (P-value ≤ 0.05). CONCLUSION TBR50 is robust metric for reduced spill-in and increased CNR.
Collapse
Affiliation(s)
- Mercy I. Akerele
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, LS2 9NL UK
| | - Nouf A. Mushari
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, LS2 9NL UK
| | - Rachael O. Forsythe
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
- Edinburgh Imaging Facility, Queen’s Medical Research Institute, University of Edinburgh, Edinburgh, UK
| | - Maaz Syed
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
- Edinburgh Imaging Facility, Queen’s Medical Research Institute, University of Edinburgh, Edinburgh, UK
| | - Nicolas A. Karakatsanis
- Division of Radiopharmaceutical Sciences, Department of Radiology, Weil Cornell Medical College of Cornell University, New York, NY USA
- Biomedical Engineering & Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, NY USA
| | - David E. Newby
- Edinburgh Imaging Facility, Queen’s Medical Research Institute, University of Edinburgh, Edinburgh, UK
| | - Marc R. Dweck
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
- Edinburgh Imaging Facility, Queen’s Medical Research Institute, University of Edinburgh, Edinburgh, UK
| | - Charalampos Tsoumpas
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, LS2 9NL UK
- Biomedical Engineering & Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, NY USA
- Invicro, London, UK
| |
Collapse
|
4
|
Bellinge JW, Schultz CJ. Optimizing arterial 18F-sodium fluoride positron emission tomography analysis. J Nucl Cardiol 2021; 28:1887-1890. [PMID: 31873832 DOI: 10.1007/s12350-019-01992-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Accepted: 11/30/2019] [Indexed: 12/19/2022]
Affiliation(s)
- Jamie W Bellinge
- School of Medicine, University of Western Australia, Perth, WA, Australia.
- Department of Cardiology, Royal Perth Hospital, 197 Wellington St, Perth, WA, 6000, Australia.
| | - Carl J Schultz
- School of Medicine, University of Western Australia, Perth, WA, Australia
- Department of Cardiology, Royal Perth Hospital, 197 Wellington St, Perth, WA, 6000, Australia
| |
Collapse
|
5
|
Lassen ML, Slomka PJ. Cardiac PET/MR: Are sophisticated attenuation correction techniques necessary for clinical routine assessments? J Nucl Cardiol 2021; 28:2205-2206. [PMID: 32034663 DOI: 10.1007/s12350-020-02057-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 01/24/2020] [Indexed: 10/25/2022]
Affiliation(s)
- Martin Lyngby Lassen
- Artificial Intelligence in Medicine Program, Cedars-Sinai Medical Center, 8700 Beverly Blvd. Ste. A047, Los Angeles, CA, 90048, USA.
| | - Piotr J Slomka
- Artificial Intelligence in Medicine Program, Cedars-Sinai Medical Center, 8700 Beverly Blvd. Ste. A047, Los Angeles, CA, 90048, USA
| |
Collapse
|
6
|
Deidda D, Akerele MI, Aykroyd RG, Dweck MR, Ferreira K, Forsythe RO, Heetun W, Newby DE, Syed M, Tsoumpas C. Improved identification of abdominal aortic aneurysm using the Kernelized Expectation Maximization algorithm. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2021; 379:20200201. [PMID: 33966459 PMCID: PMC8107650 DOI: 10.1098/rsta.2020.0201] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Abdominal aortic aneurysm (AAA) monitoring and risk of rupture is currently assumed to be correlated with the aneurysm diameter. Aneurysm growth, however, has been demonstrated to be unpredictable. Using PET to measure uptake of [18F]-NaF in calcified lesions of the abdominal aorta has been shown to be useful for identifying AAA and to predict its growth. The PET low spatial resolution, however, can affect the accuracy of the diagnosis. Advanced edge-preserving reconstruction algorithms can overcome this issue. The kernel method has been demonstrated to provide noise suppression while retaining emission and edge information. Nevertheless, these findings were obtained using simulations, phantoms and a limited amount of patient data. In this study, the authors aim to investigate the usefulness of the anatomically guided kernelized expectation maximization (KEM) and the hybrid KEM (HKEM) methods and to judge the statistical significance of the related improvements. Sixty-one datasets of patients with AAA and 11 from control patients were reconstructed with ordered subsets expectation maximization (OSEM), HKEM and KEM and the analysis was carried out using the target-to-blood-pool ratio, and a series of statistical tests. The results show that all algorithms have similar diagnostic power, but HKEM and KEM can significantly recover uptake of lesions and improve the accuracy of the diagnosis by up to 22% compared to OSEM. The same improvements are likely to be obtained in clinical applications based on the quantification of small lesions, like for example cancer. This article is part of the theme issue 'Synergistic tomographic image reconstruction: part 1'.
Collapse
Affiliation(s)
| | - Mercy I. Akerele
- Biomedical Imaging Science Department, University of Leeds, Leeds, UK
- Department of Radiology, Weill Cornell Medicine, New York, NY, USA
| | | | - Marc R. Dweck
- Edinburgh Imaging Facility, Queen’s Medical Research Institute, Edinburgh, UK
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | | | - Rachael O. Forsythe
- Edinburgh Imaging Facility, Queen’s Medical Research Institute, Edinburgh, UK
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | | | - David E. Newby
- Edinburgh Imaging Facility, Queen’s Medical Research Institute, Edinburgh, UK
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - Maaz Syed
- Edinburgh Imaging Facility, Queen’s Medical Research Institute, Edinburgh, UK
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | | |
Collapse
|
7
|
Wong JM, Puri T, Siddique MM, Frost ML, Moore AEB, Blake GM, Fogelman I. Comparison of ordered-subset expectation maximization and filtered back projection reconstruction based on quantitative outcome from dynamic [18F]NaF PET images. Nucl Med Commun 2021; 42:699-706. [PMID: 33625180 DOI: 10.1097/mnm.0000000000001393] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
[18F]NaF PET imaging is a useful tool for measuring regional bone metabolism. However, due to tracer in urine, [18F]NaF PET images of the hip reconstructed using filtered back projection (FBP) frequently show streaking artifacts in slices through the bladder leading to noisy time-activity curves unsuitable for quantification. This study compares differences between quantitative outcomes at the hip derived from images reconstructed using the FBP and ordered-subset expectation maximization (OSEM) methods. Dynamic [18F]NaF PET data at the hip for four postmenopausal women were reconstructed using FBP and nine variations of the OSEM algorithm (all combinations of 1, 5, 15 iterations and 10, 15, 21 subsets). Seven volumes of interest were placed in the hip. Bone metabolism was measured using standardized uptake values, Patlak analysis (Ki-PAT) and Hawkins model Ki-4k. Percentage differences between the standardized uptake values and Ki values from FBP and OSEM images were assessed. OSEM images appeared visually smoother and without the streaking artifacts seen with FBP. However, due to loss of counts, they failed to recover the quantitative values in VOIs close to the bladder, including the femoral head and femoral neck. This was consistent for all quantification methods. Volumes of interest farther from the bladder or larger and receiving greater counts showed good convergence with 5 iterations and 21 subsets. For VOIs close to the bladder, including the femoral neck and femoral head, 15 iterations and 10, 15 or 21 subsets were not enough to obtain OSEM images suitable for measuring bone metabolism and showed no improvement compared to FBP.
Collapse
Affiliation(s)
- James M Wong
- Department of Anaesthesia, Royal Berkshire Hospitals NHS Foundation Trust, Reading
| | - Tanuj Puri
- Department of Biomedical Engineering, School of Biomedical Engineering and Imaging Sciences, Kings College London, St Thomas' Hospital, London
| | | | - Michelle L Frost
- Clinical Trials & Statistics Unit (ICR-CTSU), Institute of Cancer Research, Sutton
| | - Amelia E B Moore
- Department of Biomedical Engineering, School of Biomedical Engineering and Imaging Sciences, Kings College London, St Thomas' Hospital, London
| | - Glen M Blake
- Department of Biomedical Engineering, School of Biomedical Engineering and Imaging Sciences, Kings College London, St Thomas' Hospital, London
| | - Ignac Fogelman
- Osteoporosis Research Unit, Guy's & St Thomas' Hospital, King's College London, London, UK
| |
Collapse
|
8
|
Bell M, Gandhi R, Shawer H, Tsoumpas C, Bailey MA. Imaging Biological Pathways in Abdominal Aortic Aneurysms Using Positron Emission Tomography. Arterioscler Thromb Vasc Biol 2021; 41:1596-1606. [PMID: 33761759 DOI: 10.1161/atvbaha.120.315812] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
[Figure: see text].
Collapse
Affiliation(s)
- Michael Bell
- Leeds Institute of Cardiovascular and Metabolic Medicine, School of Medicine, University of Leeds, United Kingdom
| | - Richa Gandhi
- Leeds Institute of Cardiovascular and Metabolic Medicine, School of Medicine, University of Leeds, United Kingdom
| | - Heba Shawer
- Leeds Institute of Cardiovascular and Metabolic Medicine, School of Medicine, University of Leeds, United Kingdom
| | - Charalampos Tsoumpas
- Leeds Institute of Cardiovascular and Metabolic Medicine, School of Medicine, University of Leeds, United Kingdom
| | - Marc A Bailey
- Leeds Institute of Cardiovascular and Metabolic Medicine, School of Medicine, University of Leeds, United Kingdom
| |
Collapse
|
9
|
Akerele MI, Karakatsanis NA, Deidda D, Cal-Gonzalez J, Forsythe RO, Dweck MR, Syed M, Newby DE, Aykroyd RG, Sourbron S, Tsoumpas C. Comparison of Correction Techniques for the Spill in Effect in Emission Tomography. IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES 2020; 4:422-432. [PMID: 33542967 DOI: 10.1109/trpms.2020.2980443] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
In positron emission tomography (PET) imaging, accurate clinical assessment is often affected by the partial volume effect (PVE) leading to overestimation (spill-in) or underestimation (spill-out) of activity in various small regions. The spill-in correction, in particular, can be very challenging when the target region is close to a hot background region. Therefore, this study evaluates and compares the performance of various recently developed spill-in correction techniques, namely: background correction (BC), local projection (LP), and hybrid kernelized (HKEM) methods. We used a simulated digital phantom and [18F]-NaF PET data of three patients with abdominal aortic aneurysms (AAA) acquired with Siemens Biograph mMR™ and mCT™ scanners respectively. Region of Interest (ROI) analysis was performed and the extracted SUV mean , SUV max and target-to-background ratio (TBR) scores were compared. Results showed substantial spill-in effects from hot regions to targeted regions, which are more prominent in small structures. The phantom experiment demonstrated the feasibility of spill-in correction with all methods. For the patient data, large differences in SUV mean , SUV max and TBR max scores were observed between the ROIs drawn over the entire aneurysm and ROIs excluding some regions close to the bone. Overall, BC yielded the best performance in spill-in correction in both phantom and patient studies.
Collapse
Affiliation(s)
- Mercy I Akerele
- Biomedical Imaging Science Department, Faculty of Medicine and Health, University of Leeds, UK; Department of Radiology, Weil Cornell Medical College of Cornell University, NY, USA
| | - Nicolas A Karakatsanis
- Department of Radiology, Weil Cornell Medical College of Cornell University, NY, USA; Biomedical Engineering and Imaging Institute, Icahn School of Medicine at Mount Sinai, NY
| | - Daniel Deidda
- Biomedical Imaging Science Department, Faculty of Medicine and Health, University of Leeds, UK; Department of Statistics, University of Leeds, UK; Nuclear Medicine Imaging, Medical Radiation Physics, National Physical Laboratory, London, UK
| | | | | | | | | | | | | | - Steven Sourbron
- Biomedical Imaging Science Department, Faculty of Medicine and Health, University of Leeds, UK
| | - Charalampos Tsoumpas
- Biomedical Imaging Science Department, Faculty of Medicine and Health, University of Leeds, UK; Biomedical Engineering and Imaging Institute, Icahn School of Medicine at Mount Sinai, NY
| |
Collapse
|