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1.
J Migr Health ; 8: 100206, 2023.
Article in English | MEDLINE | ID: mdl-38047140

ABSTRACT

Venezuelan migrant and refugee women and girls (VMRWG) face risks of exposure to and infection from HIV and threats of multiple forms of violence (including GBV) during and after migration. Yet, there is a lack of evidence on barriers and facilitators to VMRWGs' access to HIV prevention and care services this population at all stages of their migration. We addressed this evidence gap by conducting a qualitative study composed of fifty-four semi-structured interviews with practitioners (n = 24) and VMRWG (n = 30) in the two largest receiving cities of migrants in Colombia. We sought to identify perceived barriers and facilitators to HIV prevention and care to inform policies and programmatic efforts. Analysis followed a theory-informed approach using the Socioecological Model. Findings describe multi-level barriers to access to HIV prevention and care related to discrimination, gender-based violence, rigid gender norms, lack of information and system fragmentation. Policies that integrate community-based networks and support intersectoral work are pivotal to breach the gaps between services and communities and develop a gender-sensitive approach that tackles the relationship between gender-based violence and HIV risk.

2.
Physiol Rep ; 11(15): e15773, 2023 08.
Article in English | MEDLINE | ID: mdl-37549967

ABSTRACT

Hypoxic ischemic encephalopathy (HIE) occurs in 2-5/1000 births, with acute kidney injury (AKI) occurring in 40%. AKI increases morbidity and mortality. Caffeine, an adenosine receptor antagonist, and photobiomodulation (PBM), working on cytochrome c oxidase, are potential treatments for AKI. To examine effects of caffeine and PBM on AKI in rats, Day 7 pups underwent a HIE intervention (Modified Rice-Vannucci model) replicating pathology observed in humans. Caffeine was administered for 3 days and/or PBM for 5 days following HIE. Weights and urine for biomarkers (NGAL, albumin, KIM-1, osteopontin) were collected prior to HIE, daily post intervention and at sacrifice. Both treatments reduced kidney injury seen on electron microscopy, but not when combined. HIE elevated urinary NGAL and albumin on Days 1-3 post-HIE, before returning to control levels. This elevation was significantly reduced by PBM or caffeine. KIM-1 was significantly elevated for 7 days post-HIE and was reduced by both treatments. Osteopontin was not altered by HIE or the treatments. Treatments, individually but not in combination, improved HIE-induced reductions in the enzymatic activity of mitochondrial complexes II-III. PBM and caffeine also improved weight gain. PBM and caffeine reduces AKI diagnosed by urinary biomarkers and confirmed by EM findings.


Subject(s)
Acute Kidney Injury , Hypoxia-Ischemia, Brain , Humans , Animals , Rats , Animals, Newborn , Lipocalin-2 , Caffeine/pharmacology , Caffeine/therapeutic use , Ischemia , Hypoxia-Ischemia, Brain/therapy , Biomarkers , Acute Kidney Injury/etiology , Acute Kidney Injury/therapy , Albumins
4.
Clin Radiol ; 76(8): 553-558, 2021 08.
Article in English | MEDLINE | ID: mdl-34053731

ABSTRACT

We present a multimodality pictorial review of axillary lymphadenopathy in patients recently vaccinated against COVID-19. As the mass vaccination programme continues to be rolled out worldwide in an effort to combat the pandemic, it is important that radiologists consider recent COVID-19 vaccination in the differential diagnosis of unilateral axillary lymphadenopathy and are aware of typical appearances across all imaging methods. We review current guidelines on the management of unilateral axillary lymphadenopathy in the context of recent COVID-19 vaccination.


Subject(s)
Axilla/diagnostic imaging , COVID-19 Vaccines , COVID-19/prevention & control , Lymphadenopathy/chemically induced , Lymphadenopathy/diagnostic imaging , Practice Guidelines as Topic , Humans , Mass Vaccination , Pandemics , SARS-CoV-2
5.
S Afr Med J ; 110(9): 850-854, 2020 Aug 31.
Article in English | MEDLINE | ID: mdl-32880266

ABSTRACT

While adolescent mothers' postpartum return to school offers long-term benefits, returning too early in the absence of sufficient support may impede the healthy development of their children. This study assessed the rates of adolescent mothers' return to school in South Africa (SA) and examined how many months after birth school-aged girls resumed schooling. Two independent studies recruited 1 114 adolescent mothers in Eastern Cape Province and Durban, respectively. Across the two studies, 64.7% (n=649) and 47.8% (n=53) of mothers, respectively, had returned to school at the time of the study. Of these mothers, the majority had returned to school within the first 2 months post partum (study 1: 67.6%; n=439; and study 2: 58.5%; n=31), fewer between 2 and 6 months (16.9%; n=110; and 22.6%; n=12), and after 12 months (2.0%; n=13; and unknown). Our findings indicate a mismatch between SA's national policy recommendations and actual return patterns, showing that a large proportion of mothers returned to school much earlier than advised. This study also highlights a particular need to amend school policies that support early-returners and their children. Additional research on the needs of mother-child dyads and studies on the impact of different timescales on educational and health outcomes are needed to further inform policy and practice regarding adolescent mothers' return to school.


Subject(s)
Mothers/statistics & numerical data , Pregnancy in Adolescence , Return to School/statistics & numerical data , Adolescent , Female , Humans , Mothers/education , Parturition , Pilot Projects , Policy , Pregnancy , Rural Population , South Africa , Surveys and Questionnaires , Time Factors , Urban Population , Young Adult
6.
Clin Radiol ; 74(2): 140-149, 2019 02.
Article in English | MEDLINE | ID: mdl-30527518

ABSTRACT

AIM: To investigate whether unenhanced cardiovascular magnetic resonance (CMR) balanced steady state free precession (bSSFP) cine images could be analysed using textural analysis (TA) software to differentiate different aetiologies of disease causing increased myocardial wall thickness (left ventricular hypertrophy [LVH]) and indicate the severity of myocardial tissue abnormality. MATERIALS AND METHODS: A mid short axis unenhanced cine frame of 216 patients comprising 50 cases of hypertrophic cardiomyopathy (HCM; predominantly Left ventricular outflow tract obstruction [LVOTO] subtype), 52 cases of cardiac amyloid (CA; predominantly AL: light chain subtype), 68 cases of aortic stenosis (AS), 15 hypertensive patients with LVH (HTN+LVH), and 31 healthy volunteers (HV) underwent TA of the CMR cine images (CMRTA) using TexRAD (TexRAD Ltd, Cambridge, UK). Among the HV, 16/31 were scanned twice to form a test-retest reproducibility cohort. CMRTA comprised a filtration-histogram technique to extract and quantify features using six parameters. RESULTS: Test-retest analysis in the HV showed a medium filter (3 mm) was the most reproducible (intra-class correlation of 0.9 for kurtosis and skewness and 0.8 for mean and SD). Disease cohorts were statistically different (p<0.001) to HV for all parameters. Pairwise comparisons of CMRTA parameters showed kurtosis and skewness was consistently significant in ranking the degree of difference from HV (greatest to least): CA, HCM, LVH+HTN, AS (p<0.001). Similarly, mean, standard deviation, entropy, and mean positive pixel (MPP) were consistent in ranking degree of difference from HV: HCM, CA, AS and HTN+LVH. CONCLUSION: Radiomic features of bSSFP CMR data sets derived using TA show promise in discriminating between the aetiologies of LVH.


Subject(s)
Hypertrophy, Left Ventricular/diagnostic imaging , Image Interpretation, Computer-Assisted/methods , Magnetic Resonance Imaging, Cine/methods , Cohort Studies , Diagnosis, Differential , Heart Ventricles/diagnostic imaging , Humans , Reproducibility of Results , Retrospective Studies , Sensitivity and Specificity
7.
NMR Biomed ; 31(4): e3900, 2018 04.
Article in English | MEDLINE | ID: mdl-29436039

ABSTRACT

Magnetic resonance imaging (MRI) studies in early Parkinson's disease (PD) have shown promise in the detection of disease-related brain changes in the white and deep grey matter. We set out to establish whether intrinsic cortical involvement in early PD can be detected with quantitative MRI. We collected a rich, multi-modal dataset, including diffusion MRI, T1 relaxometry and cortical morphometry, in 20 patients with early PD (disease duration, 1.9 ± 0.97 years, Hoehn & Yahr 1-2) and in 19 matched controls. The cortex was reconstructed using FreeSurfer. Data analysis employed linked independent component analysis (ICA), a novel data-driven technique that allows for data fusion and extraction of multi-modal components before further analysis. For comparison, we performed standard uni-modal analysis with a general linear model (GLM). Linked ICA detected multi-modal cortical changes in early PD (p = 0.015). These comprised fractional anisotropy reduction in dorsolateral prefrontal, cingulate and premotor cortex and the superior parietal lobule, mean diffusivity increase in the mesolimbic, somatosensory and superior parietal cortex, sparse diffusivity decrease in lateral parietal and right prefrontal cortex, and sparse changes to the cortex area. In PD, the amount of cortical dysintegrity correlated with diminished cognitive performance. Importantly, uni-modal analysis detected no significant group difference on any imaging modality. We detected microstructural cortical pathology in early PD using a data-driven, multi-modal approach. This pathology is correlated with diminished cognitive performance. Our results indicate that early degenerative processes leave an MRI signature in the cortex of patients with early PD. The cortical imaging findings are behaviourally meaningful and provide a link between cognitive status and microstructural cortical pathology in patients with early PD.


Subject(s)
Cerebral Cortex/pathology , Cerebral Cortex/physiopathology , Cognitive Dysfunction/physiopathology , Parkinson Disease/pathology , Parkinson Disease/physiopathology , Aging/pathology , Female , Humans , Male , Middle Aged
8.
Eur Radiol ; 27(3): 1012-1020, 2017 Mar.
Article in English | MEDLINE | ID: mdl-27380902

ABSTRACT

OBJECTIVES: The purpose of this study was to investigate the ability of computed tomography texture analysis (CTTA) to provide additional prognostic information in patients with Hodgkin's lymphoma (HL) and high-grade non-Hodgkin's lymphoma (NHL). METHODS: This retrospective, pilot-study approved by the IRB comprised 45 lymphoma patients undergoing routine 18F-FDG-PET-CT. Progression-free survival (PFS) was determined from clinical follow-up (mean-duration: 40 months; range: 10-62 months). Non-contrast-enhanced low-dose CT images were submitted to CTTA comprising image filtration to highlight features of different sizes followed by histogram-analysis using kurtosis. Prognostic value of CTTA was compared to PET FDG-uptake value, tumour-stage, tumour-bulk, lymphoma-type, treatment-regime, and interim FDG-PET (iPET) status using Kaplan-Meier analysis. Cox regression analysis determined the independence of significantly prognostic imaging and clinical features. RESULTS: A total of 27 patients had aggressive NHL and 18 had HL. Mean PFS was 48.5 months. There was no significant difference in pre-treatment CTTA between the lymphoma sub-types. Kaplan-Meier analysis found pre-treatment CTTA (medium feature scale, p=0.010) and iPET status (p<0.001) to be significant predictors of PFS. Cox analysis revealed that an interaction between pre-treatment CTTA and iPET status was the only independent predictor of PFS (HR: 25.5, 95% CI: 5.4-120, p<0.001). Specifically, pre-treatment CTTA risk stratified patients with negative iPET. CONCLUSION: CTTA can potentially provide prognostic information complementary to iPET for patients with HL and aggressive NHL. KEY POINTS: • CT texture-analysis (CTTA) provides prognostic information complementary to interim FDG-PET in Lymphoma. • Pre-treatment CTTA and interim PET status were significant predictors of progression-free survival. • Patients with negative interim PET could be further stratified by pre-treatment CTTA. • Provide precision surveillance where additional imaging reserved for patients at greatest recurrence-risk. • Assists in risk-adapted treatment strategy based on interim PET and CTTA.


Subject(s)
Fluorodeoxyglucose F18 , Hodgkin Disease/diagnostic imaging , Lymphoma, Non-Hodgkin/diet therapy , Positron-Emission Tomography/methods , Tomography, X-Ray Computed/methods , Adult , Aged , Aged, 80 and over , Disease-Free Survival , Female , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Pilot Projects , Prognosis , Radiopharmaceuticals , Reproducibility of Results , Retrospective Studies , Risk Assessment , Young Adult
9.
Colorectal Dis ; 19(4): 349-362, 2017 Apr.
Article in English | MEDLINE | ID: mdl-27538267

ABSTRACT

AIM: The study aimed to investigate whether textural features of rectal cancer on MRI can predict long-term survival in patients treated with long-course chemoradiotherapy. METHOD: Textural analysis (TA) using a filtration-histogram technique of T2-weighted pre- and 6-week post-chemoradiotherapy MRI was undertaken using TexRAD, a proprietary software algorithm. Regions of interest enclosing the largest cross-sectional area of the tumour were manually delineated on the axial images and the filtration step extracted features at different anatomical scales (fine, medium and coarse) followed by quantification of statistical features [mean intensity, standard deviation, entropy, skewness, kurtosis and mean of positive pixels (MPP)] using histogram analysis. Cox multiple regression analysis determined which univariate features including textural, radiological and histological independently predicted overall survival (OS), disease-free survival (DFS) and recurrence-free survival (RFS). RESULTS: MPP [fine texture, hazard ratio (HR) 6.9, 95% CI: 2.43-19.55, P < 0.001], mean (medium texture, HR 5.6, 95% CI: 1.4-21.7, P = 0.007) and extramural venous invasion (EMVI) on MRI (HR 2.96, 95% CI: 1.04-8.37, P = 0.041) independently predicted OS while mean (medium texture, HR 4.53, 95% CI: 1.58-12.94, P = 0.003), MPP (fine texture, HR 3.36, 95% CI: 1.36-8.31, P = 0.008) and threatened circumferential resection margin (CRM) on MRI (HR 3.1, 95% CI: 1.01-9.46, P = 0.046) predicted DFS. For OS, EMVI on MRI (HR 4.23, 95% CI: 1.41-12.69, P = 0.01) and for DFS kurtosis (medium texture, HR 3.97, 95% CI: 1.44-10.94, P = 0.007) and CRM involvement on MRI (HR 3.36, 95% CI: 1.21-9.32, P = 0.02) were the independent post-treatment factors. Only TA independently predicted RFS on pre- or post-treatment analyses. CONCLUSION: MR based TA of rectal cancers can predict outcome before undergoing surgery and could potentially select patients for individualized therapy.


Subject(s)
Chemoradiotherapy/mortality , Magnetic Resonance Imaging/statistics & numerical data , Rectal Neoplasms/diagnostic imaging , Rectal Neoplasms/pathology , Rectum/pathology , Aged , Biomarkers, Tumor/analysis , Chemoradiotherapy/methods , Disease-Free Survival , Female , Humans , Magnetic Resonance Imaging/methods , Male , Middle Aged , Predictive Value of Tests , Proportional Hazards Models , Rectal Neoplasms/therapy , Regression Analysis , Retrospective Studies , Time Factors , Treatment Outcome
10.
BMJ Open Respir Res ; 3(1): e000156, 2016.
Article in English | MEDLINE | ID: mdl-27843550

ABSTRACT

INTRODUCTION: Solitary pulmonary nodules (SPNs) are common on CT. The most cost-effective investigation algorithm is still to be determined. Dynamic contrast-enhanced CT (DCE-CT) is an established diagnostic test not widely available in the UK currently. METHODS AND ANALYSIS: The SPUtNIk study will assess the diagnostic accuracy, clinical utility and cost-effectiveness of DCE-CT, alongside the current CT and 18-flurodeoxyglucose-positron emission tomography) (18FDG-PET)-CT nodule characterisation strategies in the National Health Service (NHS). Image acquisition and data analysis for 18FDG-PET-CT and DCE-CT will follow a standardised protocol with central review of 10% to ensure quality assurance. Decision analytic modelling will assess the likely costs and health outcomes resulting from incorporation of DCE-CT into management strategies for patients with SPNs. ETHICS AND DISSEMINATION: Approval has been granted by the South West Research Ethics Committee. Ethics reference number 12/SW/0206. The results of the trial will be presented at national and international meetings and published in an Health Technology Assessment (HTA) Monograph and in peer-reviewed journals. TRIAL REGISTRATION NUMBER: ISRCTN30784948; Pre-results.

11.
Br J Radiol ; 88(1052): 20150121, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26090825

ABSTRACT

OBJECTIVE: To investigate the level of psychological burden experienced by patients undergoing positron emission tomography (PET)/MRI scanning compared with PET/CT. METHODS: 100 adult patients referred for PET/CT and underwent PET/MRI scanning were eligible. Initial state, psychological burden of PET/CT and PET/MRI, scan satisfaction and preference were assessed using a purpose-designed questionnaire, comprising 61 five-point Likert scale questions and a three-point tick box question indicating preference between PET/CT and PET/MRI. State anxiety was assessed using the state portion of the State Trait Anxiety Inventory. Wilcoxon signed-rank tests compared psychological burden experienced by participants following PET/CT and PET/MRI scan. RESULTS: A greater level of psychological burden was experienced by patients during PET/MRI than PET/CT p ≤ 0.001, consistent with patients' preference for PET/CT over PET/MRI (p = 0.013). There was a significant relationship between PET/CT psychological burden and initial state (r = 0.386, p ≤ 0.001). No significant relationship was identified between Initial state and psychological burden of PET MRI (r = -0.089; p = 217). There was a significant relationship between psychological burden of PET/CT and PET/MRI (r = 0.354; p = 0.001). CONCLUSION: Patients' experience increased psychological burden during PET/MRI compared with PET/CT. Previous scanning experiences and patients' interactions prior to and during PET/MRI improved patient satisfaction. Interventions could be implemented to improve imaging outcome. ADVANCES IN KNOWLEDGE: This study provides evidence for the increased psychological burden of PET/MRI compared with PET/CT, and that people prefer the PET/CT procedure. We have shown that the patients who expressed a preference for PET/MRI demonstrated significantly lower psychological burden for that procedure than those that preferred PET/CT, which indicates that the benefit of reduced psychological burden could be facilitated by an appropriate intervention.


Subject(s)
Anxiety/etiology , Magnetic Resonance Imaging/psychology , Multimodal Imaging/psychology , Positron-Emission Tomography/psychology , Tomography, X-Ray Computed/psychology , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Patient Preference , Patient Satisfaction , Stress, Psychological/etiology , Surveys and Questionnaires , Young Adult
13.
Br J Radiol ; 87(1038): 20140065, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24597512

ABSTRACT

Tumour heterogeneity has, in recent times, come to play a vital role in how we understand and treat cancers; however, the clinical translation of this has lagged behind advances in research. Although significant advancements in oncological management have been made, personalized care remains an elusive goal. Inter- and intratumour heterogeneity, particularly in the clinical setting, has been difficult to quantify and therefore to treat. The histological quantification of heterogeneity of tumours can be a logistical and clinical challenge. The ability to examine not just the whole tumour but also all the molecular variations of metastatic disease in a patient is obviously difficult with current histological techniques. Advances in imaging techniques and novel applications, alongside our understanding of tumour heterogeneity, have opened up a plethora of non-invasive biomarker potential to examine tumours, their heterogeneity and the clinical translation. This review will focus on how various imaging methods that allow for quantification of metastatic tumour heterogeneity, along with the potential of developing imaging, integrated with other in vitro diagnostic approaches such as genomics and exosome analyses, have the potential role as a non-invasive biomarker for guiding the treatment algorithm.


Subject(s)
Diagnostic Imaging/methods , Genomics/methods , Molecular Imaging , Neoplasm Metastasis/genetics , Neoplasm Metastasis/pathology , Biomarkers, Tumor/genetics , Cell Transformation, Neoplastic/genetics , Epigenesis, Genetic/genetics , Gene Expression Regulation, Neoplastic , Genetic Heterogeneity , Genetic Predisposition to Disease , Humans , Molecular Targeted Therapy , Neoplasm Metastasis/diagnosis , Precision Medicine/methods , Tumor Microenvironment
14.
Acta Paediatr ; 102(9): 868-75, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23789919

ABSTRACT

AIM: Olfactory sensation is highly functional early in human neonatal life, with studies suggesting that odours can influence behaviour and infant-mother bonding. Due to its good spatial properties, blood oxygen level-dependent (BOLD) contrast functional magnetic resonance imaging (fMRI) has the potential to rapidly advance our understanding of the neural activity which underlies the development of olfactory perception in this key period. We aimed to design an 'olfactometer' specifically for use with neonatal subjects for fMRI studies of odour perception. METHODS: We describe a fully automated and programmable, fMRI compatible system capable of presenting odorant liquids. To prevent contamination of the system and minimize between-subject infective risk, the majority of the olfactometer is constructed from single-use, readily available clinical equipment. The system was used to present the odour of infant formula milk in a validation group of seven neonatal subjects at term equivalent postmenstrual age (median age 40 weeks). RESULTS: A safe, reliable and reproducible pattern of stimulation was delivered leading to well-localized positive BOLD functional responses in the piriform cortex, amygdala, thalamus, insular cortex and cerebellum. CONCLUSIONS: The described system is therefore suitable for detailed studies of the ontology of olfactory sensation and perception during early human brain development.


Subject(s)
Diagnosis, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Olfactory Nerve/anatomy & histology , Olfactory Pathways/anatomy & histology , Olfactory Perception/physiology , Cohort Studies , Female , Humans , Infant, Newborn , Male , Neonatal Screening/methods , Prospective Studies , Sensitivity and Specificity , Smell/physiology
15.
Q J Nucl Med Mol Imaging ; 57(4): 383-90, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23752688

ABSTRACT

AIM: The novel solid state dedicated cardiac cameras provide fast high resolution cardiac imaging. The D-SPECT camera enables semi-reclining (upright) positioning, increasing comfort and potentially reducing movement during myocardial perfusion imaging. Physicians are generally familiar with supine imaging and the different positioning in upright imaging could potentially cause diagnostic challenges. The aim of this study was to compare the upright and supine imaging for diagnostic ability to assess Physician confidence and determine any artefacts in upright imaging. METHODS: Fifty-five patients underwent myocardial perfusion imaging on the D-SPECT camera in both upright and supine positions. Where both images showed the same defects the 2 techniques were regarded as equally diagnostic. Where only one set showed a defect this was regarded as artefact and was defined as non-diagnostic. The location and cause of the artefact was recorded. RESULTS: In 13 /55 patients either form of imaging was regarded as equally diagnostic. In 24/55 the supine images revealed artefact affecting interpretation. The reasons for this were most frequently large BMI, motion and gut uptake. In 18/55 upright images were considered non-diagnostic. In 16/18 this was due to an infero-apical defect seen in female patients (14/16) with raised BMI and/or large breasts. CONCLUSION: Upright myocardial perfusion imaging on D-SPECT shows a common artefact (in up to 1/3 of cases) in the infero-apical region mainly in overweight female patients. Getting acquainted with this artefact this may increase Physician confidence in reporting, similarly as to conventional supine imaging. Indeed, some of the artefacts seen on supine imaging appear less commonly with upright imaging. Thus, upright imaging can potentially be used alone for diagnosis with D-SPECT. Performance of both supine and upright imaging can be reserved for overweight patients thereby minimizing impact on scanning time and clinical throughput in busy departments.


Subject(s)
Artifacts , Coronary Artery Disease/diagnostic imaging , Image Enhancement/instrumentation , Myocardial Perfusion Imaging/instrumentation , Patient Positioning/instrumentation , Signal Processing, Computer-Assisted/instrumentation , Tomography, Emission-Computed, Single-Photon/instrumentation , Adult , Aged , Aged, 80 and over , Equipment Design , Equipment Failure Analysis , Female , Humans , Male , Middle Aged , Reproducibility of Results , Sensitivity and Specificity
16.
Eur Radiol ; 22(7): 1430-41, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22367468

ABSTRACT

Dynamic contrast-enhanced computed tomography (DCE-CT) assesses the vascular support of tumours through analysis of temporal changes in attenuation in blood vessels and tissues during a rapid series of images acquired with intravenous administration of iodinated contrast material. Commercial software for DCE-CT analysis allows pixel-by-pixel calculation of a range of validated physiological parameters and depiction as parametric maps. Clinical studies support the use of DCE-CT parameters as surrogates for physiological and molecular processes underlying tumour angiogenesis. DCE-CT has been used to provide biomarkers of drug action in early phase trials for the treatment of a range of cancers. DCE-CT can be appended to current imaging assessments of tumour response with the benefits of wide availability and low cost. This paper sets out guidelines for the use of DCE-CT in assessing tumour vascular support that were developed using a Delphi process. Recommendations encompass CT system requirements and quality assurance, radiation dosimetry, patient preparation, administration of contrast material, CT acquisition parameters, terminology and units, data processing and reporting. DCE-CT has reached technical maturity for use in therapeutic trials in oncology. The development of these consensus guidelines may promote broader application of DCE-CT for the evaluation of tumour vascularity. Key Points • DCE-CT can robustly assess tumour vascular support • DCE-CT has reached technical maturity for use in therapeutic trials in oncology • This paper presents consensus guidelines for using DCE-CT in assessing tumour vascularity.


Subject(s)
Contrast Media/standards , Forecasting , Neoplasms/diagnostic imaging , Neovascularization, Pathologic/diagnostic imaging , Practice Guidelines as Topic , Tomography, X-Ray Computed/standards , Tomography, X-Ray Computed/trends , Humans , Neoplasms/blood supply , Reference Standards
17.
Magn Reson Med ; 65(4): 1173-83, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21337417

ABSTRACT

The accuracy of cerebral blood flow (CBF) estimates from arterial spin labeling (ASL) is affected by the presence of both gray matter (GM) and white matter within any voxel. Recently a partial volume (PV) correction method for ASL has been demonstrated (Asllani et al. Magn Reson Med 2008; 60:1362-1371), where PV estimates were used with a local linear regression to separate the GM and white matter ASL signal. Here a new PV correction method for multi-inversion time ASL is proposed that exploits PV estimates within a spatially regularized kinetic curve model analysis. The proposed method exploits both PV estimates and the different kinetics of the ASL signal arising from GM and white matter. The new correction method is shown, on both simulated and real data, to provide correction of GM CBF comparable to a linear regression approach, whilst preserving greater spatial detail in the CBF image. On real data corrected GM CBF values were found to be largely independent of GM PV, implying that the correction had been successful. Increases of mean GM CBF after correction of 69-80% were observed.


Subject(s)
Artifacts , Cerebral Arteries/physiology , Image Enhancement/methods , Image Interpretation, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Magnetic Resonance Angiography/methods , Cerebral Arteries/anatomy & histology , Humans , Reproducibility of Results , Sensitivity and Specificity , Spin Labels
18.
Colorectal Dis ; 13(5): 532-7, 2011 May.
Article in English | MEDLINE | ID: mdl-20070338

ABSTRACT

AIM: Anal squamous cell carcinoma (SCC) is uncommon in the western world but continues to increase in incidence. Optimal treatment and outcome are dependent upon pretreatment staging strategies. We evaluate the role of ¹8fluoro-deoxyglucose (¹8FDG) combined position emission and computed tomography (PETCT) in the management of anal SCC. METHOD: Patients with a histologically confirmed anal SCC underwent standard staging investigations, including computed tomography, Magnetic resonance imaging and examination under anaesthetic. A tumour, node, metastasis (TNM) system was used. All patients subsequently underwent additional whole-body ¹8FDG PETCT scanning. Management was planned accordingly, blinded to ¹8FDG PETCT findings, at a multidisciplinary meeting, and reviewed again following disclosure of PETCT results. RESULTS: Forty patients (24 men), with a median age of 57 years (range 38-87 years), were prospectively recruited. All primary tumours were ¹8FDG avid. PETCT did not alter the T stage but did result in disease upstaging (N and M stages). Management was altered in five (12.5%) patients: one patient was identified to have an isolated distant metastasis, and four patients had ¹8FDG-avid lymph nodes not otherwise detected, all of which were tumour-positive on fine needle aspiration cytology/biopsy. CONCLUSION: PETCT upstages anal SCC and influences subsequent management. PETCT should be considered in the staging of anal SCC, although the definitive benefit of such a strategy requires further evaluation.


Subject(s)
Anus Neoplasms/diagnosis , Carcinoma, Squamous Cell/diagnosis , Neoplasm Staging/methods , Positron-Emission Tomography , Tomography, X-Ray Computed , Adult , Aged , Aged, 80 and over , Anus Neoplasms/therapy , Carcinoma, Squamous Cell/therapy , Disease Management , Female , Fluorodeoxyglucose F18 , Humans , Lymphatic Metastasis , Magnetic Resonance Imaging , Male , Middle Aged , Neoplasm Metastasis , Prospective Studies
19.
Early Hum Dev ; 85(12): 779-83, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19926413

ABSTRACT

BACKGROUND: Very low birth weight (VLBW) infants (weight <1500 g) are increasingly cared for without prolonged periods of positive pressure ventilation (PPV). AIMS: To develop a system for 3.0 T magnetic resonance (MR) image acquisition from VLBW infants who are not receiving PPV, and to test the clinical stability of a consecutive cohort of such infants. DESIGN: Seventy VLBW infants whose median weight at image acquisition was 940 g (590-1490) underwent brain MR imaging with the developed care system as participants in research. Twenty infants (29%) received nasal continuous positive airway pressure (nCPAP), 28 (40%) received supplemental oxygen by nasal cannulae, and 22 (31%) breathed spontaneously in air during the MR examination. RESULTS: There were no significant adverse events. Seventy-six percent had none or transient self-correcting oxygen desaturations. Desaturations that required interruption of the scan for assessment were less common among infants receiving nCPAP (2/20) or breathing spontaneously in air (2/22), compared with those receiving nasal cannulae oxygen (13/28), p=0.003. Sixty-four (91%) infants had an axillary temperature > or =36 degrees C at completion of the scan (lowest 35.7 degrees C), There was no relationship between weight (p=0.167) or use of nCPAP (p=0.453) and axillary temperature <36 degrees C. No infant became hyperthermic. CONCLUSION: VLBW infants who do not require ventilation by endotracheal tube can be imaged successfully and safely at 3.0 T, including those receiving nCPAP from a customised system.


Subject(s)
Infant, Very Low Birth Weight , Magnetic Resonance Imaging/methods , Patient-Centered Care/methods , Birth Weight/physiology , Continuity of Patient Care , Humans , Infant, Newborn , Infant, Premature/physiology , Intensive Care, Neonatal/methods , Intubation, Intratracheal , Magnetic Resonance Imaging/adverse effects , Magnetic Resonance Imaging/instrumentation , Oxygen Inhalation Therapy/methods , Patient Care Team/organization & administration , Patient Positioning/methods , Positive-Pressure Respiration/methods , Safety
20.
Eur J Vasc Endovasc Surg ; 38(1): 93-9, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19217326

ABSTRACT

OBJECTIVES: Abdominal aortic aneurysms (AAAs) are associated with an inflammatory cell infiltrate and enzymatic degradation of the vessel wall. The aim of this study was to detect increased metabolic activity in the wall of the AAA with 18F-fluorodeoxyglucose ((18)F-FDG), mediated by glucose transporter protein (GLUTs), using a dedicated hybrid PET/64-detector CT. DESIGN, METHOD AND MATERIALS: 14 patients (All male, mean age 73.6 years, range 61-82) with AAA under surveillance underwent PET/CT scanning with 175 MBq of intravenous (18)F-FDG. The maximum aneurysm diameter and calcification score were determined on the attenuation correction CT. A volume of interest was placed on the aneurysm sac and the maximum Standardised Uptake Value (SUV(max)) measured. RESULTS: The mean aneurysm diameter was 5.4 cm (SD+/-0.8). Two aneurysms had the CT characteristics of inflammatory aneurysms. Twelve aneurysms showed increased FDG uptake (SUV(max)>2.5). There was no significant difference in FDG uptake between heavily calcified aneurysms and non-heavily calcified aneurysms (t-test). There was a significant increase in the FDG uptake in the two inflammatory aneurysms compared to the other twelve aneurysms (t-test; P=0.04). CONCLUSION: The findings in this study offer in vivo evidence that the AAA wall shows increased glucose metabolism, mediated by the GLUTs: this increased metabolic activity as detected by PET/CT may be present in most AAAs.


Subject(s)
Aorta, Abdominal/metabolism , Aortic Aneurysm, Abdominal/metabolism , Energy Metabolism/physiology , Fluorodeoxyglucose F18/pharmacokinetics , Glucose/metabolism , Positron-Emission Tomography/methods , Radiopharmaceuticals/pharmacokinetics , Aged , Aged, 80 and over , Aorta, Abdominal/diagnostic imaging , Aortic Aneurysm, Abdominal/diagnostic imaging , Fluorodeoxyglucose F18/administration & dosage , Humans , Injections, Intravenous , Male , Middle Aged , Prognosis , Radiopharmaceuticals/administration & dosage
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