The Impact of Acquisition Time on Image Quality in Whole-Body 18F-FDG PET/CT for Cancer Staging

SummaryThe clinical significance of 18F-FDG-PET/CT in the follow-up of patients with differentiated thyroid carcinoma was evaluated and the results were compared with those of 18F-FDGPET, 131I-whole-body scintigraphy including SPECT/CT (WBS) and ultrasound. In addition, it was the aim to investigate the impact of 18F-FDG-PET/CT on the therapeutic management. Patients, methods: 327 patients (209 women, 118 men; mean age 53 ± 18 years) with differentiated thyroid cancer (242 papillary, 75 follicular, 6 mixed, 1 Hürthle cell and 3 poorly differentiated tumours) were analyzed retrospectively at four tertiary referral centres. 289 18F-FDG-PET/CT and 118 18F-FDG-PET studies were performed in these patients between 2007 and 2010. In addition, an overall clinical evaluation was performed, including cytology, histology, thyroglobulin level, ultrasound, WBS, and subsequent clinical course in order to compare the molecular imaging results. Finally, the change in therapeutic management due to findings of 18F-FDG-PET/CT was investigated. Results: The sensitivity of 18F-FDG-PET/CT was 92%, the specificity was 95%. Sensitivity and specificity of 18F-FDG-PET alone were 67% and 93%, respectively. WBS showed a sensitivity of 65% and a specificity of 94%. The corresponding values of ultrasound were 37% and 94%, respectively. The sensitivity of 18F-FDG-PET/CT in the group of patients with a negative WBS (n=194) amounted to 96%. When 18F-FDG-PET/CT and WBS were considered in combination, tumour tissue was missed in only 2 out of 133 patients; when 18F-FDG-PET and WBS were combined, tumour tissue was missed in 1 out of 24 patients. 18F-FDG-PET/CT resulted in management change in 43% (n=57/133) with a decision on surgical approach in 20% (n=27/133). Conclusions: 18F-FDG-PET/CT is superior to 18F-FDG-PET alone in patients with differentiated thyroid cancer and has a direct impact on the therapeutic management of patients with suspected local recurrence or metastases, particularly in those with negative WBS.

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Feasibility of equivalent performance of 3D TOF [18F]-FDG PET/CT with reduced acquisition time using clinical and semiquantitative parameters

EJNMMI Research ◽

10.1186/s13550-021-00784-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Julia Pilz ◽

Lukas Hehenwarter ◽

Georg Zimmermann ◽

Gundula Rendl ◽

Gregor Schweighofer-Zwink ◽

...

Keyword(s):

Image Quality ◽

Fdg Pet ◽

Lesion Detection ◽

Whole Body ◽

Body Region ◽

Acquisition Time ◽

Routine Practice ◽

Short Acquisition Time ◽

Pet Ct ◽

Fdg Pet Ct

Abstract Background High-performance time-of-flight (TOF) positron emission tomography (PET) systems have the capability for rapid data acquisition while preserving diagnostic image quality. However, determining a reliable and clinically applicable cut-off of the acquisition time plays an important role in routine practice. This study aimed to assess the diagnostic equivalence of short acquisition time of 57 with routine 75 seconds per bed position (s/BP) of [18F]-fluoro-deoxy-glucose (FDG) PET. Phantom studies applying EARL criteria suggested the feasibility of shortened acquisition time in routine clinical imaging by 3D TOF PET/CT scanners. Ninety-six patients with melanoma, lung or head and neck cancer underwent a standard whole-body, skull base-to-thigh or vertex-to-thigh [18F]-FDG PET/CT examination using the 3D TOF Ingenuity TF PET/CT system (Philips, Cleveland, OH). The [18F]-FDG activity applied was equal to 4MBq per kg body weight. Retrospectively, PET list-mode data were used to calculate a second PET study per patient with a reduced acquisition time of 57 s instead of routine 75 s/BP. PET/CT data were reconstructed using a 3D OSEM TOF algorithm. Blinded patient data were analysed by two nuclear medicine physicians. The number of [18F]-FDG-avid lesions per body region (head&neck, thorax, abdomen, bone, extremity) and image quality (grade 1–5) were evaluated. Semiquantitative analyses were performed by standardized uptake value (SUV) measurements using 3D volume of interests (VOI). The visual and semiquantitative diagnostic equivalence of 214 [18F]-FDG-avid lesions were analysed in the routine standard (75 s/BP) as well as the calculated PET/CT studies with short acquisition time. Statistical analyses were performed by equivalence testing and Bland–Altman plots. Results Lesion detection rate per patient’s body region agreed in > 98% comparing 57 s/BP and 75 s/BP datasets. Overall image quality was determined as equal or superior to 75 s in 80% and 69%, respectively. In the semiquantitative lesion-based analyses, a significant equivalence was found between the 75 s/BP and 57 s/BP PET/CT images both for SUVmax (p = 0.004) and SUVmean (p = 0.003). Conclusion The results of this study demonstrate significant clinical and semiquantitative equivalence between short acquisition time of 57 s/BP and standard 75 s/BP 3D TOF [18F]-FDG PET/CT scanning, which may improve the patient’s workflow in routine practice.

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Reducing Radiation Exposure to Paediatric Patients Undergoing [18F]FDG-PET/CT Imaging

Molecular Imaging and Biology ◽

10.1007/s11307-021-01601-4 ◽

2021 ◽

Author(s):

Hunor Kertész ◽

Thomas Beyer ◽

Kevin London ◽

Hamda Saleh ◽

David Chung ◽

...

Keyword(s):

Image Quality ◽

Fdg Pet ◽

Signal To Noise Ratio ◽

Paediatric Oncology ◽

Whole Body ◽

Oncology Patients ◽

Pet Ct ◽

18F Fdg ◽

Noise Ratio ◽

Fdg Pet Ct

Abstract Purpose To investigate the possibility of reducing the injected activity for whole-body [18F]FDG-PET/CT studies of paediatric oncology patients and to assess the usefulness of time-of-flight (TOF) acquisition on PET image quality at reduced count levels. Procedures Twenty-nine paediatric oncology patients (12F/17M, 3–18 years old (median age 13y), weight 45±20 kg, BMI 19±4 kg/m2), who underwent routine whole-body PET/CT examinations on a Siemens Biograph mCT TrueV system with TOF capability (555ps) were included in this study. The mean injected activity was 156 ± 45 MBq (3.8 ± 0.8 kg/MBq) and scaled to patient weight. The raw data was collected in listmode (LM) format and pre-processed to simulate reduced levels of [18F]FDG activity (75, 50, 35, 20 and 10% of the original counts) by randomly removing events from the original LM data. All data were reconstructed using the vendor-specific e7-tools with standard OSEM only, with OSEM plus resolution recovery (PSF). The reconstructions were repeated with added TOF (TOF) and PSF+TOF. The benefit of TOF together with the reduced count levels was evaluated by calculating the gains in signal-to-noise ratio (SNR) in the liver and contrast-to-noise ratio (CNR) in all PET-positive lesions before and after TOF employed at every simulated reduced count level. Finally, the PSF+TOF images at 50, 75 and 100% of counts were evaluated clinically on a 5-point scale by three nuclear medicine physicians. Results The visual inspection of the reconstructed images did not reveal significant differences in image quality between 75 and 100% count levels for PSF+TOF. The improvements in SNR and CNR were the greatest for TOF reconstruction and PSF combined. Both SNR and CNR gains did increase linearly with the patients BMI for both OSEM only and PSF reconstruction. These benefits were observed until reducing the counts to 50 and 35% for SNR and CNR, respectively. Conclusions The benefit of using TOF was noticeable when using 50% or greater of the counts when evaluating the CNR and SNR. For [18F]FDG-PET/CT, whole-body paediatric imaging the injected activity can be reduced to 75% of the original dose without compromising PET image quality.

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Whole-Body [18F]FDG PET/CT Can Alter Diagnosis in Patients with Suspected Rheumatic Disease

Diagnostics ◽

10.3390/diagnostics11112073 ◽

2021 ◽

Vol 11 (11) ◽

pp. 2073

Author(s):

Matthias Fröhlich ◽

Sebastian Serfling ◽

Takahiro Higuchi ◽

Martin G. Pomper ◽

Steven P. Rowe ◽

...

Keyword(s):

Rheumatic Disease ◽

Fdg Pet ◽

Final Diagnosis ◽

Whole Body ◽

Diagnostic Uncertainty ◽

Pet Ct ◽

18F Fdg ◽

Fdg Pet Ct ◽

The Impact ◽

Suspected Diagnosis

The 2-deoxy-d-[18F]fluoro-D-glucose (FDG) positron emission tomography/computed tomography (PET/CT) is widely utilized to assess the vascular and articular inflammatory burden of patients with a suspected diagnosis of rheumatic disease. We aimed to elucidate the impact of [18F]FDG PET/CT on change in initially suspected diagnosis in patients at the time of the scan. Thirty-four patients, who had undergone [18F]FDG PET/CT, were enrolled and the initially suspected diagnosis prior to [18F]FDG PET/CT was compared to the final diagnosis. In addition, a semi-quantitative analysis including vessel wall-to-liver (VLR) and joint-to-liver (JLR) ratios was also conducted. Prior to [18F]FDG PET/CT, 22/34 (64.7%) of patients did not have an established diagnosis, whereas in 7/34 (20.6%), polymyalgia rheumatica (PMR) was suspected, and in 5/34 (14.7%), giant cell arteritis (GCA) was suspected by the referring rheumatologists. After [18F]FDG PET/CT, the diagnosis was GCA in 19/34 (55.9%), combined GCA and PMR (GCA + PMR) in 9/34 (26.5%) and PMR in the remaining 6/34 (17.6%). As such, [18F]FDG PET/CT altered suspected diagnosis in 28/34 (82.4%), including in all unclear cases. VLR of patients whose final diagnosis was GCA tended to be significantly higher when compared to VLR in PMR (GCA, 1.01 ± 0.08 (95%CI, 0.95–1.1) vs. PMR, 0.92 ± 0.1 (95%CI, 0.85–0.99), p = 0.07), but not when compared to PMR + GCA (1.04 ± 0.14 (95%CI, 0.95–1.13), p = 1). JLR of individuals finally diagnosed with PMR (0.94 ± 0.16, (95%CI, 0.83–1.06)), however, was significantly increased relative to JLR in GCA (0.58 ± 0.04 (95%CI, 0.55–0.61)) and GCA + PMR (0.64 ± 0.09 (95%CI, 0.57–0.71); p < 0.0001, respectively). In individuals with a suspected diagnosis of rheumatic disease, an inflammatory-directed [18F]FDG PET/CT can alter diagnosis in the majority of the cases, particularly in subjects who were referred because of diagnostic uncertainty. Semi-quantitative assessment may be helpful in establishing a final diagnosis of PMR, supporting the notion that a quantitative whole-body read-out may be useful in unclear cases.

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Low positive yield from routine inclusion of the brain in whole-body 18F-FDG PET/CT imaging for noncerebral malignancies

Nuclear Medicine Communications ◽

10.1097/mnm.0b013e32836066c0 ◽

2013 ◽

Vol 34 (6) ◽

pp. 540-543 ◽

Cited By ~ 8

Author(s):

Kuruva Manohar ◽

Anish Bhattacharya ◽

Bhagwant R. Mittal

Keyword(s):

Fdg Pet ◽

Ct Imaging ◽

Whole Body ◽

Pet Ct ◽

18F Fdg ◽

Fdg Pet Ct ◽

The Brain

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Comparison of the diagnostic performance and impact on management of 18F-FDG PET/CT and whole-body MRI in multiple myeloma

European Journal of Nuclear Medicine and Molecular Imaging ◽

10.1007/s00259-020-05182-2 ◽

2021 ◽

Author(s):

Olwen Westerland ◽

◽

Ashik Amlani ◽

Christian Kelly-Morland ◽

Michal Fraczek ◽

...

Keyword(s):

Multiple Myeloma ◽

Clinical Data ◽

Bone Disease ◽

Fdg Pet ◽

Diagnostic Performance ◽

Whole Body ◽

Bone Lesions ◽

Pet Ct ◽

18F Fdg ◽

Fdg Pet Ct

Abstract Purpose Comparative data on the impact of imaging on management is lacking for multiple myeloma. This study compared the diagnostic performance and impact on management of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) and whole-body magnetic resonance imaging (WBMRI) in treatment-naive myeloma. Methods Forty-six patients undergoing 18F-FDG PET/CT and WBMRI were reviewed by a nuclear medicine physician and radiologist, respectively, for the presence of myeloma bone disease. Blinded clinical and imaging data were reviewed by two haematologists in consensus and management recorded following clinical data ± 18F-FDG PET/CT or WBMRI. Bone disease was defined using International Myeloma Working Group (IMWG) criteria and a clinical reference standard. Per-patient sensitivity for lesion detection was established. McNemar test compared management based on clinical assessment ± 18F-FDG PET/CT or WBMRI. Results Sensitivity for bone lesions was 69.6% (32/46) for 18F-FDG PET/CT (54.3% (25/46) for PET component alone) and 91.3% (42/46) for WBMRI. 27/46 (58.7%) of cases were concordant. In 19/46 patients (41.3%) WBMRI detected more focal bone lesions than 18F-FDG PET/CT. Based on clinical data alone, 32/46 (69.6%) patients would have been treated. Addition of 18F-FDG PET/CT to clinical data increased this to 40/46 (87.0%) patients (p = 0.02); and WBMRI to clinical data to 43/46 (93.5%) patients (p = 0.002). The difference in treatment decisions was not statistically significant between 18F-FDG PET/CT and WBMRI (p = 0.08). Conclusion Compared to 18F-FDG PET/CT, WBMRI had a higher per patient sensitivity for bone disease. However, treatment decisions were not statistically different and either modality would be appropriate in initial staging, depending on local availability and expertise.

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POSITRON EMISSION TOMOGRAPHY WITH 18F -FDG IN THE DIAGNOSIS OF PROSTHETIC HEART VALVE ENDOCARDITIS

Emergency Cardiology and Cardiovascular Risks ◽

10.51922/2616-633x.2021.5.2.1151 ◽

2021 ◽

Vol 5 (1) ◽

pp. 1151-1160

Author(s):

A.S. Lukashevich ◽

Keyword(s):

Computed Tomography ◽

Positron Emission Tomography ◽

Fdg Pet ◽

Prosthetic Heart Valve ◽

Emission Tomography ◽

Whole Body ◽

Positron Emission ◽

Pet Ct ◽

18F Fdg ◽

Fdg Pet Ct

Purpose. The purpose of the article is to evaluate the diagnostic significance of positron emission tomography / computed tomography with 18F -fluorodeoxyglucose (18F -FDG PET/CT) for the diagnosis of prosthetic endocarditis. Methods of research. The study included 82 patients with suspected prosthetic endocarditis in accordance with the criteria proposed by Duke University [1-5]. The patients received hospital treatment at the State Institution RSPC "Cardiology" from January 2016 to March 2021. The study was of a prospective, non-randomized, single-center cohort design. The duration of the monitor period was 12 months from the moment of patients’ inclusion in the study. Whole-body positron emission tomography / computed tomography (PET/CT) examinations were performed in 82 patients. 27 patients were selected for surgical treatment. Conservative treatment group included 16 patients. 27 patients were selected into the observation group, they were suspected to have prosthetic heart valve infection in the primary referral and underwent PET/CT scanning, according to which the diagnosis of prosthetic endocarditis was excluded. The event under the study did not develop in this group during the year of observation. Results and conclusion. The history of infective endocarditis was not statistically significant and did not increase the risk of developing prosthetic endocarditis in the sample presented. The Duke criteria are less reliable in establishing the diagnosis of prosthetic endocarditis. The median number of days from the date of the first prosthesis implantation to the onset of prosthetic endocarditis was about 4 years. This study revealed that the development of the infectious process in the area of the prosthesis was noted in a more distant postoperative period compared to literature data. Histological confirmation of infection was noted in 100% (27 patients) of cases in reoperated patients. The presence of a more formidable complication such as valve ring abscess located mainly in the projection of the aortic valve ring was quite common in both groups. Presepsin and Interleukin-6 have a statistically significant (U = 394,50 p = 0,01 and U = 94,50 p = 0.004) value in the prognosis of prosthetic endocarditis. Considering the data obtained from ROC analysis, it can be said that the cut-off point at which it is possible to diagnose prosthetic endocarditis based on PETCT is 2.85. The presented methods for the interpretation of whole-body FDG-PET/CT images of patients with suspected infectious complications after cardiac surgery, as well as with the presence of prosthetic endocarditis, show high sensitivity and specificity.

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The Value of 18 Fluorine-fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Imaging in Breast Cancer Staging

Open Access Macedonian Journal of Medical Sciences ◽

10.3889/oamjms.2020.5525 ◽

2020 ◽

Vol 8 (A) ◽

pp. 970-975

Author(s):

Ahmed Tawakol ◽

Maha Khalil ◽

Yasser G. Abdelhafez ◽

Mai Hussein ◽

Mohamed Fouad Osman

Keyword(s):

Breast Cancer ◽

Computed Tomography ◽

Fdg Pet ◽

Cancer Staging ◽

Emission Tomography ◽

Breast Cancer Staging ◽

Positron Emission ◽

Pet Ct ◽

18F Fdg ◽

Fdg Pet Ct

BACKGROUND: Accurate staging is important for management decisions in patients with newly diagnosed breast cancer. AIM: This study was conducted to evaluate the value of 18 fluorine-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) imaging in breast cancer staging.. METHODS: A prospective study of 80 patients (1 male and 79 female) mean age 51.13 years with histologically confirmed breast cancer. The staging procedures included history, physical examination, mammography, and CT of neck, chest, abdomen, and pelvis; then, PET/CT was performed in a time interval <30 days. The findings of PET/CT were compared with those of the other conventional methods. RESULTS: The agreement between conventional methods (mammography, breast ultrasound, contrast-enhanced CT of the neck, chest, abdomen, and pelvis) and 18F FDG-PET/CT was 0.6 for assessing the T stage, 0.39 for N stage, and 0.75 for M stage. There was moderate agreement between CT and 18F FDG-PET/CT in the detection of nodal lesions (K=0.6) and pulmonary lesions (K=0.51), while a perfect agreement was noted for detecting osseous (K=0.82) and liver lesions (K=0.81). In total, 50 patients (62.5%) were concordantly staged between the conventional imaging and 18F-FDG PET/CT, while 30 patients (37.5%) showed a different tumor, node, and metastasis stage. The changes were driven by the detection of additional findings (n=26) or exclusion of findings (n=4), mainly at the lymph nodes (LNs) and/or distant sites. Regarding N status, 18F FDG-PET/CT revealed previously unknown regional lymphatic spread in supraclavicular (n=4; 5%), infraclavicular (n=11; 13.7%), and internal mammary (n=12; 15%) lymph node groups. 18F-FDG PET/CT changed M status in a total of four patients (5%); three of them were upstaged by detecting distant metastases, while osseous deposits were excluded in one patient leading to downstaging. CONCLUSION: 18F-FDG-PET/CT is considered a valuable imaging tool in the initial staging of breast cancer, which significantly impacts the overall American Joint Committee on Cancer staging in 37.5% of our study population.

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Leydig cell tumor of the testis: an incidental finding at 18F-FDG PET/CT imaging

Egyptian Journal of Radiology and Nuclear Medicine ◽

10.1186/s43055-021-00646-3 ◽

2021 ◽

Vol 52 (1) ◽

Author(s):

Almalki Yassir

Keyword(s):

Leydig Cell ◽

Fdg Pet ◽

Chronic Rejection ◽

Ct Imaging ◽

The Body ◽

Whole Body ◽

Pet Ct ◽

18F Fdg ◽

The Right ◽

Fdg Pet Ct

Abstract Background Leydig cell tumors (LCTs) represent the most common form of stromal tumors. We reported the 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) findings of a patient with testicular LCT. Case presentation A 50-year-old man with a history of end-stage renal disease and renal transplantation 19 years ago. One year earlier, he started to have a chronic rejection. During the investigation to determine the cause of chronic rejection, a suspicious lesion in the graft with a collection around it was seen on ultrasound (US) images, raising the possibility of post-transplant lymphoproliferative disorder (PTLD). The patient was referred for further evaluation by whole body 18F-FDG PET/CT imaging. The image finding revealed an incidental hypermetabolic focal lesion in the right testicle—no other specific findings in the remaining parts of the body nor definitive FDG avid lymphadenopathy to suggest PTLD. Testicular US was requested and showed a well-defined right-sided heterogeneous hypoechoic intratesticular focal mass at the upper pole of the right testis with significant internal vascularity on the color Doppler imaging. The patient underwent a right radical orchidectomy, and the tumor was pathologically confirmed as an LCT. Conclusion In our case, 18F-FDG-PET/CT has been helpful in incidentally detecting this rare testicular tumor in a patient with suspected PTLD.

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