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Seizure Oct 2021Posterior quadrant disconnection (PQD) is a surgical procedure for medically refractory epilepsy (MRE) involving diffuse regions of the temporo-parieto-occipital lobes.... (Review)
Review
PURPOSE
Posterior quadrant disconnection (PQD) is a surgical procedure for medically refractory epilepsy (MRE) involving diffuse regions of the temporo-parieto-occipital lobes. We sought to compare factors and efficacy according to PQD extent.
METHODS
We performed a systematic review of the literature reporting the use of PQD since 2004. We analyzed various characteristics of pooled cases, including the role of preoperative studies in patient selection, intraoperative techniques, and outcomes.
RESULTS
Our review of 137 patients from nine studies revealed 66% undergoing total PQD and 34% undergoing partial PQD. Interictal electroencephalography (EEG) findings were predominantly characterized as lateralized for total PQD (56%) and localized within the ipsilateral posterior quadrant in patients undergoing partial PQD (53%). Metabolic functional studies [positron emission tomography (PET) or ictal single-photon emission computed tomography (SPECT)] played a role in surgical decision-making in 42% of patients who underwent total PQD. Wada and/or functional magnetic resonance imaging (fMRI) was more often utilized for partial PQD (22%) than total PQD (3%) as was intracranial electroencephalography (icEEG) (30% versus 13%, respectively). Overall, 75% of total PQD patients achieved seizure freedom [defined as Engel I or International League Against Epilepsy (ILAE) Class 1 outcome] in comparison to 63% of partial PQD patients (p = .078). New visual field deficits were seen in 12% and new or worsened hemiparesis in 6%. For patients in either cohort, concordance of interictal and ictal EEG findings was found to be predictive of seizure freedom (p = .048).
CONCLUSION
Both total and partial PQD represent effective alternatives for managing patients with MRE whose seizure onset zone (SOZ) involves a diffuse region within the posterior quadrant. While PET and/or SPECT frequently aided in the decision to proceed with total PQD, patients who underwent a tailored, partial multilobar resection were more likely to undergo Wada and/or fMRI testing as well as stage I icEEG studies.
Topics: Drug Resistant Epilepsy; Electroencephalography; Epilepsy; Humans; Magnetic Resonance Imaging; Positron-Emission Tomography; Retrospective Studies; Tomography, Emission-Computed, Single-Photon; Treatment Outcome
PubMed: 34102378
DOI: 10.1016/j.seizure.2021.05.018 -
Diseases of the Esophagus : Official... May 2023Radiomics can interpret radiological images with more detail and in less time compared to the human eye. Some challenges in managing esophageal cancer can be addressed... (Meta-Analysis)
Meta-Analysis
Performance of radiomics-based artificial intelligence systems in the diagnosis and prediction of treatment response and survival in esophageal cancer: a systematic review and meta-analysis of diagnostic accuracy.
Radiomics can interpret radiological images with more detail and in less time compared to the human eye. Some challenges in managing esophageal cancer can be addressed by incorporating radiomics into image interpretation, treatment planning, and predicting response and survival. This systematic review and meta-analysis provides a summary of the evidence of radiomics in esophageal cancer. The systematic review was carried out using Pubmed, MEDLINE, and Ovid EMBASE databases-articles describing radiomics in esophageal cancer were included. A meta-analysis was also performed; 50 studies were included. For the assessment of treatment response using 18F-FDG PET/computed tomography (CT) scans, seven studies (443 patients) were included in the meta-analysis. The pooled sensitivity and specificity were 86.5% (81.1-90.6) and 87.1% (78.0-92.8). For the assessment of treatment response using CT scans, five studies (625 patients) were included in the meta-analysis, with a pooled sensitivity and specificity of 86.7% (81.4-90.7) and 76.1% (69.9-81.4). The remaining 37 studies formed the qualitative review, discussing radiomics in diagnosis, radiotherapy planning, and survival prediction. This review explores the wide-ranging possibilities of radiomics in esophageal cancer management. The sensitivities of 18F-FDG PET/CT scans and CT scans are comparable, but 18F-FDG PET/CT scans have improved specificity for AI-based prediction of treatment response. Models integrating clinical and radiomic features facilitate diagnosis and survival prediction. More research is required into comparing models and conducting large-scale studies to build a robust evidence base.
Topics: Humans; Positron Emission Tomography Computed Tomography; Fluorodeoxyglucose F18; Artificial Intelligence; Radiomics; Esophageal Neoplasms
PubMed: 37236811
DOI: 10.1093/dote/doad034 -
Arab Journal of Urology Dec 2020: To evaluate the current literature on the accuracy of fluoro-2-deoxy--glucose positron emission tomography-computed tomography (FDG PET-CT) for lymph node (LN) staging... (Review)
Review
Performance of fluoro-2-deoxy-D-glucose positron emission tomography-computed tomography imaging for lymph node staging in bladder and upper tract urothelial carcinoma: a systematic review.
: To evaluate the current literature on the accuracy of fluoro-2-deoxy--glucose positron emission tomography-computed tomography (FDG PET-CT) for lymph node (LN) staging in urothelial carcinoma (UC), as robust evidence on the value of this technology in UC is still lacking. : The Medical Literature Analysis and Retrieval System Online (MEDLINE)/PubMed, Cochrane Library, and Scopus databases were searched for eligible studies. We included all original studies evaluating FDG PET-CT in bladder or upper tract UC. The search results were restricted to the English language, and included prospective and retrospective studies without time restriction. We included only studies reporting the sensitivity and specificity of FDG PET-CT in detecting UC LN metastases. : We identified 23 articles meeting our inclusion criteria. In the preoperative setting, the sensitivity of FDG PET-CT for detecting LN metastases in patients with bladder cancer was widely variable ranging from 23% to 89%; the specificity ranged from 81% to 100%; and the overall accuracy ranged from 65% to 89%. During bladder cancer monitoring the sensitivity for detecting LN metastases ranged from 75% to 92% and the specificity ranged from 60% to 92%. The sensitivity for LN staging in upper tract UC ranged between 82% and 95%, with a specificity of 84-91%. : Despite the inconsistencies in sensitivity between the reports, FDG PET-CT seems to have a high specificity for LN staging in patients with UC. Future prospective, well-designed studies are necessary to evaluate the role of FDG PET-CT in UC management. FDG: fluoro-2-deoxy--glucose; LN: lymph node; PET: positron emission tomography; PRISMA: Preferred Reporting Items for Systematic Reviews and Meta-analyses; PSMA: prostate-specific membrane antigen; (N)(P)PV: (negative) (positive) predictive value; QUADAS-2: Quality Assessment of Diagnostic Accuracy Studies-2; SUV: maximum standard uptake value; (UT)UC: (upper urinary tract) urothelial carcinoma.
PubMed: 33763249
DOI: 10.1080/2090598X.2020.1858012 -
Journal of Cerebral Blood Flow and... May 2016Noninvasive imaging of cerebral blood flow provides critical information to understand normal brain physiology as well as to identify and manage patients with... (Comparative Study)
Comparative Study Review
Noninvasive imaging of cerebral blood flow provides critical information to understand normal brain physiology as well as to identify and manage patients with neurological disorders. To date, the reference standard for cerebral blood flow measurements is considered to be positron emission tomography using injection of the [(15)O]-water radiotracer. Although [(15)O]-water has been used to study brain perfusion under normal and pathological conditions, it is not widely used in clinical settings due to the need for an on-site cyclotron, the invasive nature of arterial blood sampling, and experimental complexity. As an alternative, arterial spin labeling is a promising magnetic resonance imaging technique that magnetically labels arterial blood as it flows into the brain to map cerebral blood flow. As arterial spin labeling becomes more widely adopted in research and clinical settings, efforts have sought to standardize the method and validate its cerebral blood flow values against positron emission tomography-based cerebral blood flow measurements. The purpose of this work is to critically review studies that performed both [(15)O]-water positron emission tomography and arterial spin labeling to measure brain perfusion, with the aim of better understanding the accuracy and reproducibility of arterial spin labeling relative to the positron emission tomography reference standard.
Topics: Arteries; Brain; Cerebrovascular Circulation; Humans; Magnetic Resonance Angiography; Oxygen Radioisotopes; Positron-Emission Tomography; Spin Labels; Water
PubMed: 26945019
DOI: 10.1177/0271678X16636393 -
Theranostics 2023Recent studies suggest that Ga-FAPI PET/CT demonstrated superiority over F-FDG PET/CT in the evaluation of various cancer types, especially in gastric cancer (GC). By... (Meta-Analysis)
Meta-Analysis
Recent studies suggest that Ga-FAPI PET/CT demonstrated superiority over F-FDG PET/CT in the evaluation of various cancer types, especially in gastric cancer (GC). By comprehensively reviewing and analysing the differences between Ga-FAPI and F-FDG in GC, some evidence is provided to foster the broader clinical application of FAPI PET imaging. In this review, studies published up to July 3, 2023, that employed radionuclide labelled FAPI as a diagnostic radiotracer for PET in GC were analysed. These studies were sourced from both the PubMed and Web of Science databases. Our statistical analysis involved a bivariate meta-analysis of the diagnostic data and a meta-analysis of the quantitative metrics. These were performed using R language. The meta-analysis included 14 studies, with 527 patients, of which 358 were diagnosed with GC. Overall, Ga-FAPI showed higher pooled sensitivity (0.84 [95% CI 0.67-0.94] 0.46 [95% CI 0.32-0.60]), specificity (0.91 [95% CI 0.76-0.98] 0.88 [95% CI 0.74-0.96]) and area under the curve (AUC) (0.92 [95% CI 0.77-0.98] 0.52 [95% CI 0.38-0.86]) than F-FDG. The evidence showed superior pooled sensitivities of Ga-FAPI PET over F-FDG for primary tumours, local recurrence, lymph node metastases, distant metastases, and peritoneal metastases. Furthermore, Ga-FAPI PET provided higher maximum standardized uptake value (SUVmax) and tumour-to-background ratios (TBR). For bone metastases, while Ga-FAPI PET demonstrated slightly lower patient-based pooled sensitivity (0.93 1.00), it significantly outperformed F-FDG in the lesion-based analysis (0.95 0.65). However, SUVmax (mean difference [MD] 1.79 [95% CI -3.87-7.45]) and TBR (MD 5.01 [95% CI -0.78-10.80]) of bone metastases showed no significant difference between Ga-FAPI PET/CT and F-FDG PET/CT. Compared with F-FDG, Ga-FAPI PET imaging showed improved diagnostic accuracy in the evaluation of GC. It can be effectively applied to the early diagnosis, initial staging, and detection of recurrence/metastases of GC. Ga-FAPI may have the potential of replacing F-FDG in GC in future applications.
Topics: Humans; Stomach Neoplasms; Positron Emission Tomography Computed Tomography; Fluorodeoxyglucose F18; Gallium Radioisotopes; Positron-Emission Tomography
PubMed: 37649615
DOI: 10.7150/thno.88335 -
JACC. Cardiovascular Imaging Feb 2015Angina without coronary artery disease (CAD) has substantial morbidity and is present in 10% to 30% of patients undergoing angiography. Coronary microvascular... (Review)
Review
Angina without coronary artery disease (CAD) has substantial morbidity and is present in 10% to 30% of patients undergoing angiography. Coronary microvascular dysfunction (CMD) is present in 50% to 65% of these patients. The optimal treatment of this cohort is undefined. We performed a systematic review to evaluate treatment strategies for objectively-defined CMD in the absence of CAD. We included studies assessing therapy in human subjects with angina and coronary flow reserve or myocardial perfusion reserve <2.5 by positron emission tomography, cardiac magnetic resonance imaging, dilution methods, or intracoronary Doppler in the absence of coronary artery stenosis ≥50% or structural heart disease. Only 8 papers met the strict inclusion criteria. The papers were heterogeneous, using different treatments, endpoints, and definitions of CMD. The small sample sizes severely limit the power of these studies, with an average of 11 patients per analysis. Studies evaluating sildenafil, quinapril, estrogen, and transcutaneous electrical nerve stimulation application demonstrated benefits in their respective endpoints. No benefit was found with L-arginine, doxazosin, pravastatin, and diltiazem. Our systematic review highlights that there is little data to support therapies for CMD. We assess the data meeting rigorous inclusion criteria and review the related but excluded published data. We additionally describe the next steps needed to address this research gap, including a standardized definition of CMD, routine assessment of CMD in studies of chest pain without obstructive CAD, and specific therapy assessment in the population with confirmed CMD.
Topics: Coronary Angiography; Coronary Circulation; Diagnosis, Differential; Humans; Magnetic Resonance Imaging, Cine; Microcirculation; Microvascular Angina; Myocardial Revascularization; Positron-Emission Tomography; Practice Guidelines as Topic; Regional Blood Flow
PubMed: 25677893
DOI: 10.1016/j.jcmg.2014.12.008 -
European Journal of Cancer (Oxford,... Mar 2016Imaging biomarkers have a potential to depict the hallmarks of cancers that characterise cancer cells as compared to normal cells. One pertinent example is... (Review)
Review
Imaging biomarkers have a potential to depict the hallmarks of cancers that characterise cancer cells as compared to normal cells. One pertinent example is 3'-deoxy-3'-(18)F-fluorothymidine positron emission tomography ([(18)F]FLT-PET), which allows non-invasive in vivo assessment of tumour proliferation. Most importantly, [(18)F]FLT does not seem to be accumulating in inflammatory processes, as seen in [(18)F]-fludeoxyglucose, the most commonly used PET tracer for assessment of cell metabolism. [(18)F]FLT could therefore provide additional information about the tumour biology before, during and after treatment. This systematic review focuses on the use of [(18)F]FLT-PET tumour uptake values as a measure of tumour response to therapeutic interventions. The clinical studies which evaluated the role of [(18)F]FLT-PET as a measure of tumour response to treatment are summarised and the evidence linking [(18)F]FLT-PET tumour uptake values with clinical outcome is evaluated.
Topics: Cell Proliferation; Dideoxynucleosides; Disease-Free Survival; Humans; Neoplasms; Positron-Emission Tomography; Predictive Value of Tests; Radiopharmaceuticals; Treatment Outcome
PubMed: 26820682
DOI: 10.1016/j.ejca.2015.11.018 -
European Journal of Cancer (Oxford,... Nov 2022Checkpoint inhibition has radically improved the perspective for patients with metastatic cancer, but predicting who will not respond with high certainty remains... (Review)
Review
BACKGROUND
Checkpoint inhibition has radically improved the perspective for patients with metastatic cancer, but predicting who will not respond with high certainty remains difficult. Imaging-derived biomarkers may be able to provide additional insights into the heterogeneity in tumour response between patients. In this systematic review, we aimed to summarise and qualitatively assess the current evidence on imaging biomarkers that predict response and survival in patients treated with checkpoint inhibitors in all cancer types.
METHODS
PubMed and Embase were searched from database inception to 29th November 2021. Articles eligible for inclusion described baseline imaging predictive factors, radiomics and/or imaging machine learning models for predicting response and survival in patients with any kind of malignancy treated with checkpoint inhibitors. Risk of bias was assessed using the QUIPS and PROBAST tools and data was extracted.
RESULTS
In total, 119 studies including 15,580 patients were selected. Of these studies, 73 investigated simple imaging factors. 45 studies investigated radiomic features or deep learning models. Predictors of worse survival were (i) higher tumour burden, (ii) presence of liver metastases, (iii) less subcutaneous adipose tissue, (iv) less dense muscle and (v) presence of symptomatic brain metastases. Hazard rate ratios did not exceed 2.00 for any predictor in the larger and higher quality studies. The added value of baseline fluorodeoxyglucose positron emission tomography parameters in predicting response to treatment was limited. Pilot studies of radioactive drug tracer imaging showed promising results. Reports on radiomics were almost unanimously positive, but numerous methodological concerns exist.
CONCLUSIONS
There is well-supported evidence for several imaging biomarkers that can be used in clinical decision making. Further research, however, is needed into biomarkers that can more accurately identify which patients who will not benefit from checkpoint inhibition. Radiomics and radioactive drug labelling appear to be promising approaches for this purpose.
Topics: Brain Neoplasms; Humans; Positron-Emission Tomography; Radiopharmaceuticals
PubMed: 36096039
DOI: 10.1016/j.ejca.2022.07.034 -
Contrast Media & Molecular Imaging Nov 2016Nowadays molecular imaging plays a vital role in achieving a successful targeted and personalized treatment. Hence, the approach of combining two or more medical imaging... (Review)
Review
Nowadays molecular imaging plays a vital role in achieving a successful targeted and personalized treatment. Hence, the approach of combining two or more medical imaging modalities was developed. The objective of this review is to systematically compare recent dual contrast agents in Positron Emission Tomography (PET)/Magnetic Resonance Imaging (MRI) and in some cases Single photon emission computed tomography (SPECT)/MRI in terms of some their characteristics, such as tumor uptake, and reticuloendothelial system uptake (especially liver) and their relaxivity rates for early detection of primary cancer tumor. To the best of our knowledge, this is the first systematic and integrated overview of this field. Two reviewers individually directed the systematic review search using PubMed, MEDLINE and Google Scholar. Two other reviewers directed quality assessment, using the criteria checklist from the CAMARADES (Collaborative Approach to Meta-Analysis and Review of Animal Data from Experimental Studies) tool, and differences were resolved by consensus. After reviewing all 49 studies, we concluded that a size range of 20-200 nm can be used for molecular imaging, although it is better to try to achieve as small a size as it is possible. Also, small nanoparticles with a hydrophilic coating and positive charge are suitable as a T contrast agent. According to our selected data, the most successful dual probes in terms of high targeting were with an average size of 40 nm, PEGylated using peptides as a biomarker and radiolabeled with copper 64 and gallium 68. Copyright © 2017 John Wiley & Sons, Ltd.
Topics: Animals; Contrast Media; Humans; Magnetic Resonance Imaging; Molecular Probes; Multimodal Imaging; Nanoparticles; Positron-Emission Tomography; Radioisotopes; Tomography, Emission-Computed, Single-Photon
PubMed: 28102031
DOI: 10.1002/cmmi.1719 -
World Journal of Nuclear Medicine 2020Stroke and other thromboembolic events in the brain are often due to carotid artery atherosclerosis, and atherosclerotic plaques with inflammation are considered... (Review)
Review
Stroke and other thromboembolic events in the brain are often due to carotid artery atherosclerosis, and atherosclerotic plaques with inflammation are considered particularly vulnerable, with an increased risk of becoming symptomatic. Positron emission tomography (PET) with 2-deoxy-2-[Fluorine-18] fluoro-D-glucose (F-FDG) provides valuable metabolic information regarding arteriosclerotic lesions and may be applied for the detection of vulnerable plaque. At present, however, patients are selected for carotid surgical intervention on the basis of the degree of stenosis alone, and not the vulnerability or inflammation of the lesion. During the past decade, research using PET with the glucose analog tracer F-fluor-deoxy-glucose, has been implemented for identifying increased tracer uptake in symptomatic carotid plaques, and tracer uptake has been shown to correlate with plaque inflammation and vulnerability. These findings imply that F-FDG PET might hold the promise for a new and better diagnostic test to identify patients eligible for carotid endarterectomy. The rationale for developing diagnostic tests based on molecular imaging with F-FDG PET, as well as methods for simple clinical PET approaches, are discussed. This is a systematic review, following Preferred Reporting Items for Systematic Reviews guidelines, which interrogated the PUBMED database from January 2001 to November 2019. The search combined the terms, "atherosclerosis," "inflammation," "FDG," and "plaque imaging." The search criteria included all types of studies, with a primary outcome of the degree of arterial vascular inflammation determined by F-FDG uptake. This review examines the role of F-FDG PET imaging in the characterization of atherosclerotic plaques.
PubMed: 33623500
DOI: 10.4103/wjnm.WJNM_26_20