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European Journal of Endocrinology Aug 2016Adrenal masses are incidentally discovered in 5% of CT scans. In 2013/2014, 81 million CT examinations were undertaken in the USA and 5 million in the UK. However,... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
Adrenal masses are incidentally discovered in 5% of CT scans. In 2013/2014, 81 million CT examinations were undertaken in the USA and 5 million in the UK. However, uncertainty remains around the optimal imaging approach for diagnosing malignancy. We aimed to review the evidence on the accuracy of imaging tests for differentiating malignant from benign adrenal masses.
DESIGN
A systematic review and meta-analysis was conducted.
METHODS
We searched MEDLINE, EMBASE, Cochrane CENTRAL Register of Controlled Trials, Science Citation Index, Conference Proceedings Citation Index, and ZETOC (January 1990 to August 2015). We included studies evaluating the accuracy of CT, MRI, or (18)F-fluoro-deoxyglucose (FDG)-PET compared with an adequate histological or imaging-based follow-up reference standard.
RESULTS
We identified 37 studies suitable for inclusion, after screening 5469 references and 525 full-text articles. Studies evaluated the accuracy of CT (n=16), MRI (n=15), and FDG-PET (n=9) and were generally small and at high or unclear risk of bias. Only 19 studies were eligible for meta-analysis. Limited data suggest that CT density >10HU has high sensitivity for detection of adrenal malignancy in participants with no prior indication for adrenal imaging, that is, masses with ≤10HU are unlikely to be malignant. All other estimates of test performance are based on too small numbers.
CONCLUSIONS
Despite their widespread use in routine assessment, there is insufficient evidence for the diagnostic value of individual imaging tests in distinguishing benign from malignant adrenal masses. Future research is urgently needed and should include prospective test validation studies for imaging and novel diagnostic approaches alongside detailed health economics analysis.
Topics: Adrenal Gland Neoplasms; Humans; Incidental Findings; Magnetic Resonance Imaging; Positron-Emission Tomography; Sensitivity and Specificity; Tomography, X-Ray Computed
PubMed: 27257145
DOI: 10.1530/EJE-16-0461 -
European Journal of Vascular and... Sep 2016Methods are required to identify abdominal aortic aneurysms (AAAs) at increased risk of rupture. Inflammatory characteristics of AAA can be visualised using advanced... (Review)
Review
BACKGROUND
Methods are required to identify abdominal aortic aneurysms (AAAs) at increased risk of rupture. Inflammatory characteristics of AAA can be visualised using advanced imaging techniques and have been proposed as potential predictors of aneurysm progression. The objective of this review was to determine which inflammatory imaging biomarkers are associated with AAA growth and rupture.
METHODS
A systematic review was carried out in accordance with the PRISMA guidelines. The electronic databases of Medline (PubMed), Embase, and the Cochrane Library were searched up to January 1, 2016 for studies to determine the potential association between inflammatory imaging biomarkers and AAA growth or rupture.
RESULTS
Seven studies were included, comprising 202 AAA patients. (18)F-fluoro-deoxy-glucose positron emission tomography ((18)F-FDG PET-CT) was evaluated in six studies. Magnetic resonance imaging with ultrasmall superparamagnetic particles of iron oxide (USPIO-MRI) was evaluated in one study. Two of six (18)F-FDG PET-CT studies reported a significant negative correlation (r=.383, p = .015) or a significant negative association (p = .04). Four of six (18)F-FDG PET-CT studies reported no significant association between (18)F-FDG uptake and AAA growth. The single study investigating USPIO-MRI demonstrated that AAA growth was three times higher in patients with focal USPIO uptake in the AAA wall compared to patients with diffuse or no USPIO uptake in the wall (0.66 vs. 0.24 vs. 0.22 cm/y, p = .020). In the single study relating (18)F-FDG uptake results to AAA rupture, the association was not significant.
CONCLUSIONS
Current evidence shows contradictory associations between (18)F-FDG uptake and AAA growth. Data on the association with rupture are insufficient. Based on the currently available evidence, neither (18)F-FDG PET-CT nor USPIO-MRI can be implemented as growth or rupture prediction tools in daily practice. The heterogeneous results reflect the complex and partially unclear relationship between inflammatory processes and AAA progression.
Topics: Aorta, Abdominal; Aortic Aneurysm, Abdominal; Aortic Rupture; Aortitis; Aortography; Computed Tomography Angiography; Contrast Media; Dextrans; Disease Progression; Fluorodeoxyglucose F18; Humans; Magnetic Resonance Angiography; Magnetite Nanoparticles; Molecular Imaging; Positron Emission Tomography Computed Tomography; Predictive Value of Tests; Radiopharmaceuticals; Reproducibility of Results; Risk Assessment; Risk Factors
PubMed: 27283346
DOI: 10.1016/j.ejvs.2016.05.002 -
Academic Radiology Nov 2021Hyposmia/anosmia is common among patients with coronavirus disease-2019 (COVID-19). Various imaging modalities have been used to assess olfactory dysfunction in...
RATIONALE AND OBJECTIVES
Hyposmia/anosmia is common among patients with coronavirus disease-2019 (COVID-19). Various imaging modalities have been used to assess olfactory dysfunction in COVID-19. In this systematic review, we sought to categorize and summarize the imaging data in COVID-19-induced anosmia.
MATERIAL AND METHODS
Eligible articles were included after a comprehensive review using online databases including Google scholar, Scopus, PubMed, Web of science and Elsevier. Duplicate results, conference abstracts, reviews, and studies in languages other than English were excluded.
RESULTS
In total, 305 patients undergoing MRI/functional MRI (177), CT of paranasal sinuses (129), and PET/CT or PET/MRI scans (14) were included. Out of a total of 218 findings reported on MRI, 80 were reported on early (≤ 1 month) and 85 on late (>1 month) imaging in relation to the onset of anosmia. Overall, OB morphology and T2-weighted or FLAIR signal intensity were normal in 68/218 (31.2%), while partial or complete opacification of OC was observed in 60/218 (27.5%). T2 hyperintensity in OB was detected in 11/80 (13.75%) and 18/85 (21.17%) on early and late imaging, respectively. Moreover, OB atrophy was reported in 1/80 (1.25%) on early and in 9/85 (10.58%) on late imaging. Last, among a total of 129 CT scans included, paranasal sinuses were evalualted in 88 (68.21%), which were reported as normal in most cases (77/88, [87.5%]).
CONCLUSION
In this systematic review, normal morphology and T2/FLAIR signal intensity in OB and OC obstruction were the most common findings in COVID-19-induced anosmia, while paranasal sinuses were normal in most cases. OC obstruction is the likely mechanism for olfactory dysfunction in COVID-19. Abnormalities in OB signal intensity and OB atrophy suggest that central mechanisms may also play a role in late stage in COVID-19-induced anosmia.
Topics: COVID-19; Humans; Magnetic Resonance Imaging; Olfaction Disorders; Positron Emission Tomography Computed Tomography; SARS-CoV-2
PubMed: 34548231
DOI: 10.1016/j.acra.2021.08.010 -
Molecular Imaging 2021Standard neuroimaging protocols for brain tumors have well-known limitations. The clinical use of additional modalities including amino acid PET (aaPET) and advanced MRI... (Review)
Review
INTRODUCTION
Standard neuroimaging protocols for brain tumors have well-known limitations. The clinical use of additional modalities including amino acid PET (aaPET) and advanced MRI (aMRI) techniques (including DWI, PWI, and MRS) is emerging in response to the need for more accurate detection of brain tumors. In this systematic review of the past 2 years of the literature, we discuss the most recent studies that directly compare or combine aaPET and aMRI for brain tumor imaging.
METHODS
A PubMed search was conducted for human studies incorporating both aaPET and aMRI and published between July 2018 and August 2020.
RESULTS
A total of 22 studies were found in the study period. Recent studies of aaPET with DWI showed a superiority of MET, FET, FDOPA, and AMT PET for detecting tumor, predicting recurrence, diagnosing progression, and predicting survival. Combining modalities further improved performance. Comparisons of aaPET with PWI showed mixed results about spatial correlation. However, both modalities were able to detect high-grade tumors, identify tumor recurrence, differentiate recurrence from treatment effects, and predict survival. aaPET performed better on these measures than PWI, but when combined, they had the strongest results. Studies of aaPET with MRS demonstrated that both modalities have diagnostic potential but MET PET and FDOPA PET performed better than MRS. MRS suffered from some data quality issues that limited analysis in two studies, and, in one study that combined modalities, overall performance actually decreased. Four recent studies compared aaPET with emerging MRI approaches (such as CEST imaging, MR fingerprinting, and SISTINA), but the initial results remain inconclusive.
CONCLUSIONS
aaPET outperformed the aMRI imaging techniques in most recent studies. DWI and PWI added meaningful complementary data, and the combination of aaPET with aMRI yielded the best results in most studies.
Topics: Amino Acids; Brain Neoplasms; Humans; Magnetic Resonance Imaging; Neuroimaging; Positron-Emission Tomography
PubMed: 34194287
DOI: 10.1155/2021/8874078 -
Diabetes Care Aug 2017Diagnosing bone infection in the diabetic foot is challenging and often requires several diagnostic procedures, including advanced imaging. We compared the diagnostic... (Comparative Study)
Comparative Study Meta-Analysis Review
OBJECTIVE
Diagnosing bone infection in the diabetic foot is challenging and often requires several diagnostic procedures, including advanced imaging. We compared the diagnostic performances of MRI, radiolabeled white blood cell (WBC) scintigraphy (either with Tc-hexamethylpropyleneamineoxime [HMPAO] or In-oxine), and [F]fluorodeoxyglucose positron emission tomography (F-FDG-PET)/computed tomography.
RESEARCH DESIGN AND METHODS
We searched Medline and Embase as of August 2016 for studies of diagnostic tests on patients known or suspected to have diabetes and a foot infection. We performed a systematic review using criteria recommended by the Cochrane Review of a database that included prospective and retrospective diagnostic studies performed on patients with diabetes in whom there was a clinical suspicion of osteomyelitis of the foot. The preferred reference standard was bone biopsy and subsequent pathological (or microbiological) examination.
RESULTS
Our review found 6,649 articles; 3,894 in Medline and 2,755 in Embase. A total of 27 full articles and 2 posters was selected for inclusion in the analysis. The performance characteristics for the F-FDG-PET were: sensitivity, 89%; specificity, 92%; diagnostic odds ratio (DOR), 95; positive likelihood ratio (LR), 11; and negative LR, 0.11. For WBC scan with In-oxine, the values were: sensitivity, 92%; specificity, 75%; DOR, 34; positive LR, 3.6; and negative LR, 0.1. For WBC scan with Tc-HMPAO, the values were: sensitivity, 91%; specificity, 92%; DOR, 118; positive LR, 12; and negative LR, 0.1. Finally, for MRI, the values were: sensitivity, 93%; specificity, 75%; DOR, 37; positive LR, 3.66, and negative LR, 0.10.
CONCLUSIONS
The various modalities have similar sensitivity, but F-FDG-PET and Tc-HMPAO-labeled WBC scintigraphy offer the highest specificity. Larger prospective studies with a direct comparison among the different imaging techniques are required.
Topics: Bone and Bones; Databases, Factual; Diabetic Foot; Humans; Leukocytes; Magnetic Resonance Imaging; Osteomyelitis; Positron-Emission Tomography; Radionuclide Imaging; Sensitivity and Specificity
PubMed: 28733376
DOI: 10.2337/dc17-0532 -
International Journal of Molecular... Jun 2023Various papers have introduced the use of positron emission tomography (PET) with [Ga]Ga-radiolabeled fibroblast-activation protein inhibitor (FAPi) radiopharmaceuticals... (Meta-Analysis)
Meta-Analysis Review
Various papers have introduced the use of positron emission tomography (PET) with [Ga]Ga-radiolabeled fibroblast-activation protein inhibitor (FAPi) radiopharmaceuticals in different subtypes of gastric cancer (GC). Our aim was to assess the diagnostic performance of this novel molecular imaging technique in GC with a systematic review and meta-analysis. A straightforward literature search of papers concerning the diagnostic performance of FAP-targeted PET imaging was performed. Original articles evaluating this novel molecular imaging examination in both newly diagnosed GC patients and GC patients with disease relapse were included. The systematic review included nine original studies, and eight of them were also eligible for meta-analysis. The quantitative synthesis provided pooled detection rates of 95% and 97% for the assessment of primary tumor and distant metastases, respectively, and a pooled sensitivity and specificity of 74% and 89%, respectively, for regional lymph node metastases. Significant statistical heterogeneity among the included studies was found only in the analysis of the primary tumor detection rate (I = 64%). Conclusions: Beyond the limitations of this systematic review and meta-analysis (i.e., all the included studies were conducted in Asia, and using [F]FDG PET/CT as a comparator of the index test), the quantitative data provided demonstrate the promising diagnostic performance of FAP-targeted PET imaging in GC. Nevertheless, more prospective multicentric studies are needed to confirm the excellent performances of FAP-targeted PET in this cluster of patients.
Topics: Humans; Positron Emission Tomography Computed Tomography; Stomach Neoplasms; Prospective Studies; Neoplasm Recurrence, Local; Positron-Emission Tomography; Radiopharmaceuticals; Fluorodeoxyglucose F18; Gallium Radioisotopes
PubMed: 37373285
DOI: 10.3390/ijms241210136 -
Clinical Orthopaedics and Related... Mar 2010Imaging protocols for suspected scaphoid fractures among investigators and hospitals are markedly inconsistent. We performed a systematic review and meta-analysis to... (Meta-Analysis)
Meta-Analysis Review
UNLABELLED
Imaging protocols for suspected scaphoid fractures among investigators and hospitals are markedly inconsistent. We performed a systematic review and meta-analysis to assess and compare the diagnostic performance of bone scintigraphy, MRI, and CT for diagnosing suspected scaphoid fractures. Twenty-six studies were included. Sensitivity, specificity, and diagnostic odds ratio were pooled separately and summary receiver operating characteristic curves were fitted for each modality. Meta-regression analyses were performed to compare these modalities. We obtained likelihood ratios derived from the pooled sensitivity and specificity and, using Bayes' theorem, calculated the posttest probability by application of the tests. The pooled sensitivity, specificity, natural logarithm of the diagnostic odds ratio, and the positive and negative likelihood ratios were, respectively, 97%, 89%, 4.78, 8.82, and 0.03 for bone scintigraphy; 96%, 99%, 6.60, 96, and 0.04 for MRI; and 93%, 99%, 6.11, 93, and 0.07 for CT. Bone scintigraphy and MRI have equally high sensitivity and high diagnostic value for excluding scaphoid fracture; however, MRI is more specific and better for confirming scaphoid fracture. We believe additional studies are needed to assess diagnostic performance of CT, especially paired design studies or randomized controlled trials to compare CT with MRI or bone scintigraphy.
LEVEL OF EVIDENCE
Level III, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.
Topics: Databases, Bibliographic; Diagnostic Imaging; Fractures, Bone; Humans; Magnetic Resonance Imaging; Odds Ratio; Predictive Value of Tests; Radionuclide Imaging; Scaphoid Bone; Tomography, X-Ray Computed; Wrist Joint
PubMed: 19756904
DOI: 10.1007/s11999-009-1081-6 -
The Cochrane Database of Systematic... Jan 2017Pulmonary embolism is a leading cause of pregnancy-related death. An accurate diagnosis in pregnant patients is crucial to prevent untreated pulmonary embolism as well... (Review)
Review
BACKGROUND
Pulmonary embolism is a leading cause of pregnancy-related death. An accurate diagnosis in pregnant patients is crucial to prevent untreated pulmonary embolism as well as unnecessary anticoagulant treatment and future preventive measures. Applied imaging techniques might perform differently in these younger patients with less comorbidity and altered physiology, who largely have been excluded from diagnostic studies.
OBJECTIVES
To determine the diagnostic accuracy of computed tomography pulmonary angiography (CTPA), lung scintigraphy and magnetic resonance angiography (MRA) for the diagnosis of pulmonary embolism during pregnancy.
SEARCH METHODS
We searched MEDLINE and Embase until July 2015. We used included studies as seeds in citations searches and in 'find similar' functions and searched reference lists. We approached experts in the field to help us identify non-indexed studies.
SELECTION CRITERIA
We included consecutive series of pregnant patients suspected of pulmonary embolism who had undergone one of the index tests (computed tomography (CT) pulmonary angiography, lung scintigraphy or MRA) and clinical follow-up or pulmonary angiography as a reference test.
DATA COLLECTION AND ANALYSIS
Two review authors performed data extraction and quality assessment. We contacted investigators of potentially eligible studies to obtain missing information. In the primary analysis, we regarded inconclusive index test results as a negative reference test, and treatment for pulmonary embolism after an inconclusive index test as a positive reference test.
MAIN RESULTS
We included 11 studies (four CTPA, five lung scintigraphy, two both) with a total of 695 CTPA and 665 lung scintigraphy results. Lung scintigraphy was applied by different techniques. No MRA studies matched our inclusion criteria.Overall, risk of bias and concerns regarding applicability were high in all studies as judged in light of the review research question, as was heterogeneity in study methods. We did not undertake meta-analysis. All studies used clinical follow-up as a reference standard, none in a manner that enabled reliable identification of false positives. Sensitivity and negative predictive value were therefore the only valid test accuracy measures.The median negative predictive value for CTPA was 100% (range 96% to 100%). Median sensitivity was 83% (range 0% to 100%).The median negative predictive value for lung scintigraphy was 100% (range 99% to 100%). Median sensitivity was 100% (range 0% to 100%).The median frequency of inconclusive results was 5.9% (range 0.9% to 36%) for CTPA and 4.0% (range 0% to 23%) for lung scintigraphy. The overall median prevalence of pulmonary embolism was 3.3% (range 0.0% to 8.7%).
AUTHORS' CONCLUSIONS
Both CTPA and lung scintigraphy seem appropriate for exclusion of pulmonary embolism during pregnancy. However, the quality of the evidence mandates cautious adoption of this conclusion. Important limitations included poor reference standards, necessary assumptions in the analysis regarding inconclusive test results and the inherent inability of included studies to identify false positives. It is unclear which test has the highest accuracy. There is a need for direct comparisons between diagnostic methods, including MR, in prospective randomized diagnostic studies.
Topics: Angiography; Female; Humans; Magnetic Resonance Angiography; Positron-Emission Tomography; Pregnancy; Pregnancy Complications, Hematologic; Pulmonary Embolism; Radionuclide Imaging; Sensitivity and Specificity; Tomography, X-Ray Computed
PubMed: 28124411
DOI: 10.1002/14651858.CD011053.pub2 -
Dementia and Geriatric Cognitive... 2013Healthcare systems face an increased prevalence of Alzheimer's disease and increasing costs. The use of molecular biomarkers and imaging could offer an effective... (Review)
Review
BACKGROUND/AIMS
Healthcare systems face an increased prevalence of Alzheimer's disease and increasing costs. The use of molecular biomarkers and imaging could offer an effective solution for these issues. The objective of this study was to assess amyloid imaging regarding clinical utility and impact.
METHODS
A literature search was performed in several databases, searching articles between 2008 and January 2013 following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The results are reported according to the clinical correlates of amyloid imaging.
RESULTS
Thirty-three studies were included in the final analysis. Five studies evaluated amyloid imaging for diagnosis. Nine studies assessed the prognostic value. Twenty-two studies provided correlations to cognitive measures. Amyloid imaging provides a high reliability in diagnosis and prognosis, but cognitive measures only showed weak correlations.
CONCLUSION
The evidence clearly indicated that amyloid imaging has not arrived yet in clinical practice. However, it can provide substantial benefits in special aspects of diagnostic accuracy and for a diagnosis up to 10 years before clinical diagnosis. This can be a base for early preventive treatment strategies such as anti-amyloid therapy. In this context, amyloid imaging is crucial to understand the early pathologic process in Alzheimer's disease.
Topics: Alzheimer Disease; Amyloid; Biomarkers; Diagnostic Imaging; Humans; Magnetic Resonance Imaging; Positron-Emission Tomography; Predictive Value of Tests; Prognosis; Reproducibility of Results; Sensitivity and Specificity
PubMed: 23949370
DOI: 10.1159/000351679 -
Seminars in Nuclear Medicine Sep 2023Fibroblast activation protein inhibitor (FAPI) is a promising tracer in oncologic positron emission tomography/computed tomography (PET/CT). Numerous studies have... (Review)
Review
Fibroblast activation protein inhibitor (FAPI) is a promising tracer in oncologic positron emission tomography/computed tomography (PET/CT). Numerous studies have demonstrated the superior sensitivity of FAPI PET/CT over fluorodeoxyglucose (FDG) PET/CT in several types of cancer. However, the cancer specificity of FAPI uptake remains understudied, and several cases of false-positive FAPI PET/CT findings have been reported. A systematic search of PubMed, Embase, and Web of Science was conducted for studies published prior to April 2022 reporting nonmalignant FAPI PET/CT findings. We included original peer-reviewed articles of studies in humans using FAPI tracers radiolabeled with Ga or F that were published in English. Papers without original data and studies with insufficient information were excluded. Nonmalignant findings were presented on a per-lesion basis and grouped according to the type of organ or tissue involved. The search identified a total of 1.178 papers, of which 108 studies were eligible. Eighty studies were case reports (74%), and the remaining 28 were cohort studies (26%). A total of 2.372 FAPI-avid nonmalignant findings were reported, with the most frequent being uptake in the arteries, e.g., related to plaques (n = 1178, 49%). FAPI uptake was also frequently related to degenerative and traumatic bone and joint lesions (n = 147, 6%) or arthritis (n = 92, 4%). For organs, diffuse or focal uptake was often seen in cases of inflammation, infection, fibrosis, and IgG4-related disease (n = 157, 7%). FAPI-avid inflammatory/reactive lymph nodes (n = 121, 5%) and tuberculosis lesions (n = 51, 2%) have been reported and could prove to be potential pitfalls in cancer staging. Periodontitis (n = 76, 3%), hemorrhoids (n = 47, 2%), and scarring/wound healing (n = 35, 2%) also presented as focal uptake on FAPI PET/CT. The present review provides an overview of the reported FAPI-avid nonmalignant PET/CT findings to date. A large number of benign clinical entities may show FAPI uptake and should be kept in mind when interpreting FAPI PET/CT findings in patients with cancer.
Topics: Humans; Biological Transport; Fluorodeoxyglucose F18; Gallium Radioisotopes; Inflammation; Positron Emission Tomography Computed Tomography
PubMed: 36813670
DOI: 10.1053/j.semnuclmed.2023.02.001