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1.
J AAPOS ; : 103963, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38955242

RESUMO

BACKGROUND: Studies describe poor follow-up among children in ophthalmology prior to the COVID-19 pandemic. Although the pandemic led to worse adherence for routine medical care in children, little information exists on pediatric ophthalmology follow-up adherence during COVID-19. The purpose of this study was to evaluate the effect of the COVID-19 pandemic on follow-up adherence for children with eye disease, and identified characteristics associated with follow-up adherence. METHODS: In this single-center study, the medical records of 519 new pediatric (≤18 years of age) patients seen during January, April, August, and December 2019 and 2021 were reviewed retrospectively. Patients were classified into two groups: adherent (patients who followed up within 30 days of recommended appointment time) or less-adherent (patients who followed up >30 days after recommended follow-up or never). Main outcome measure was patient adherence status. RESULTS: Follow-up adherence was similar before and during the COVID-19 pandemic (50.4% for 2019 and 49.6% for 2021 [P = 0.40]). Patients that were less likely to be adherent in both univariate and multivariable analyses included those with public insurance (adjusted OR = 0.63 [95% CI, 0.40-1.00]; P = 0.05), and those recommended to follow-up ≥3 months (adjusted OR ≤ 0.10; P < 0.001). In addition, in univariate analysis, those who declined to self-report race (OR = 0.53 [95% CI, 0.29-0.95]; P = 0.04) and those seen by optometrists (OR = 0.42 [95% CI, 0.29-0.60]; P < 0.001) were less likely to be adherent, while patients who traveled ≥177 miles to their provider were more likely to be adherent (OR = 2.88 [95% CI, 1.17-7.55]; P = 0.02). CONCLUSIONS: Follow-up adherence for childhood eye care was low but remained relatively stable before and during the COVID-19 pandemic; >50% of children were less-adherent.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38837669

RESUMO

In this study, we compared the fat-saturated (FS) and non-FS turbo spin echo (TSE) magnetic resonance imaging knee sequences reconstructed conventionally (conventional-TSE) against a deep learning-based reconstruction of accelerated TSE (DL-TSE) scans. A total of 232 conventional-TSE and DL-TSE image pairs were acquired for comparison. For each consenting patient, one of the clinically acquired conventional-TSE proton density-weighted sequences in the sagittal or coronal planes (FS and non-FS), or in the axial plane (non-FS), was repeated using a research DL-TSE sequence. The DL-TSE reconstruction resulted in an image resolution that increased by at least 45% and scan times that were up to 52% faster compared to the conventional TSE. All images were acquired on a MAGNETOM Vida 3T scanner (Siemens Healthineers AG, Erlangen, Germany). The reporting radiologists, blinded to the acquisition time, were requested to qualitatively compare the DL-TSE against the conventional-TSE reconstructions. Despite having a faster acquisition time, the DL-TSE was rated to depict smaller structures better for 139/232 (60%) cases, equivalent for 72/232 (31%) cases and worse for 21/232 (9%) cases compared to the conventional-TSE. Overall, the radiologists preferred the DL-TSE reconstruction in 124/232 (53%) cases and stated no preference, implying equivalence, for 65/232 (28%) cases. DL-TSE reconstructions enabled faster acquisition times while enhancing spatial resolution and preserving the image contrast. From these results, the DL-TSE provided added or comparable clinical value and utility in less time. DL-TSE offers the opportunity to further reduce the overall examination time and improve patient comfort with no loss in diagnostic accuracy.

3.
Clin Infect Dis ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38739754

RESUMO

BACKGROUND: The risk of antibiotic resistance is complicated by the potential for spillover effects from one treated population to another. Azithromycin mass drug administration programs report higher rates of antibiotic resistance among treatment arms in targeted groups. This study aims to understand the risk of spillover of antibiotic resistance to non-target groups in these programs. METHODS: Data was used from a cluster-randomized trial comparing the effect of biannual azithromycin and placebo distribution to children 1-59 months on child mortality. Nasopharyngeal samples from untreated children 7-12 years old were tested for genetic determinants of macrolide resistance (primary outcome) and resistance to other antibiotic classes (secondary outcomes). Linear regression was used to compare the community-level mean difference in prevalence by arm at the 24-month timepoint adjusting for baseline prevalence. RESULTS: 1,103 children 7-12 years old in 30 communities were included in the analysis (15 azithromycin, 15 placebo). Adjusted mean differences in prevalence of resistance determinants for macrolides, beta-lactams and tetracyclines were 3.4% (95% CI -4.1% to 10.8%, P-value 0.37), -1.2% (95% CI -7.9% to 5.5%, P-value 0.72), and -3.3% (95% CI -9.5% to 2.8%, P-value 0.61), respectively. CONCLUSIONS: We were unable to demonstrate a statistically significant increase in macrolide resistance determinants in untreated groups in an azithromycin mass drug administration program. While the result might be consistent with a small spillover effect, this study was not powered to detect such a small difference. Larger studies are warranted to better understand the potential for spillover effects within these programs.

4.
PLoS Med ; 21(5): e1004386, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38709718

RESUMO

BACKGROUND: Randomized controlled trials found that twice-yearly mass azithromycin administration (MDA) reduces childhood mortality, presumably by reducing infection burden. World Health Organization (WHO) issued conditional guidelines for mass azithromycin administration in high-mortality settings in sub-Saharan Africa given concerns for antibiotic resistance. While prolonged twice-yearly MDA has been shown to increase antibiotic resistance in small randomized controlled trials, the objective of this study was to determine if macrolide and non-macrolide resistance in the gut increases with the duration of azithromycin MDA in a larger setting. METHODS AND FINDINGS: The Macrolide Oraux pour Réduire les Décès avec un Oeil sur la Résistance (MORDOR) study was conducted in Niger from December 2014 to June 2020. It was a cluster-randomized trial of azithromycin (A) versus placebo (P) aimed at evaluating childhood mortality. This is a sub-study in the MORDOR trial to track changes in antibiotic resistance after prolonged azithromycin MDA. A total of 594 communities were eligible. Children 1 to 59 months in 163 randomly chosen communities were eligible to receive treatment and included in resistance monitoring. Participants, staff, and investigators were masked to treatment allocation. At the conclusion of MORDOR Phase I, by design, all communities received an additional year of twice-yearly azithromycin treatments (Phase II). Thus, at the conclusion of Phase II, the treatment history (1 letter per 6-month period) for the participating communities was either (PP-PP-AA) or (AA-AA-AA). In Phase III, participating communities were then re-randomized to receive either another 3 rounds of azithromycin or placebo, thus resulting in 4 treatment histories: Group 1 (AA-AA-AA-AA-A, N = 51), Group 2 (PP-PP-AA-AA-A, N = 40), Group 3 (AA-AA-AA-PP-P, N = 27), and Group 4 (PP-PP-AA-PP-P, N = 32). Rectal swabs from each child (N = 5,340) were obtained 6 months after the last treatment. Each child contributed 1 rectal swab and these were pooled at the community level, processed for DNA-seq, and analyzed for genetic resistance determinants. The primary prespecified outcome was macrolide resistance determinants in the gut. Secondary outcomes were resistance to beta-lactams and other antibiotic classes. Communities recently randomized to azithromycin (groups 1 and 2) had significantly more macrolide resistance determinants than those recently randomized to placebo (groups 3 and 4) (fold change 2.18, 95% CI 1.5 to 3.51, Punadj < 0.001). However, there was no significant increase in macrolide resistance in communities treated 4.5 years (group 1) compared to just the most recent 2.5 years (group 2) (fold change 0.80, 95% CI 0.50 to 1.00, Padj = 0.010), or between communities that had been treated for 3 years in the past (group 3) versus just 1 year in the past (group 4) (fold change 1.00, 95% CI 0.78 to 2.35, Padj = 0.52). We also found no significant differences for beta-lactams or other antibiotic classes. The main limitations of our study were the absence of phenotypic characterization of resistance, no complete placebo arm, and no monitoring outside of Niger limiting generalizability. CONCLUSIONS: In this study, we observed that mass azithromycin distribution for childhood mortality among preschool children in Niger increased macrolide resistance determinants in the gut but that resistance may plateau after 2 to 3 years of treatment. Co-selection to other classes needs to be monitored. TRIAL REGISTRATION: NCT02047981 https://classic.clinicaltrials.gov/ct2/show/NCT02047981.


Assuntos
Antibacterianos , Azitromicina , Farmacorresistência Bacteriana , Macrolídeos , Administração Massiva de Medicamentos , Humanos , Azitromicina/uso terapêutico , Níger , Pré-Escolar , Antibacterianos/uso terapêutico , Lactente , Feminino , Masculino , Macrolídeos/uso terapêutico , Mortalidade da Criança
5.
Magn Reson Med ; 92(3): 997-1010, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38778631

RESUMO

PURPOSE: QSM provides insight into healthy brain aging and neuropathologies such as multiple sclerosis (MS), traumatic brain injuries, brain tumors, and neurodegenerative diseases. Phase data for QSM are usually acquired from 3D gradient-echo (3D GRE) scans with long acquisition times that are detrimental to patient comfort and susceptible to patient motion. This is particularly true for scans requiring whole-brain coverage and submillimeter resolutions. In this work, we use a multishot 3D echo plannar imaging (3D EPI) sequence with shot-selective 2D CAIPIRIHANA to acquire high-resolution, whole-brain data for QSM with minimal distortion and blurring. METHODS: To test clinical viability, the 3D EPI sequence was used to image a cohort of MS patients at 1-mm isotropic resolution at 3 T. Additionally, 3D EPI data of healthy subjects were acquired at 1-mm, 0.78-mm, and 0.65-mm isotropic resolution with varying echo train lengths (ETLs) and compared with a reference 3D GRE acquisition. RESULTS: The appearance of the susceptibility maps and the susceptibility values for segmented regions of interest were comparable between 3D EPI and 3D GRE acquisitions for both healthy and MS participants. Additionally, all lesions visible in the MS patients on the 3D GRE susceptibility maps were also visible on the 3D EPI susceptibility maps. The interplay among acquisition time, resolution, echo train length, and the effect of distortion on the calculated susceptibility maps was investigated. CONCLUSION: We demonstrate that the 3D EPI sequence is capable of rapidly acquiring submillimeter resolutions and providing high-quality, clinically relevant susceptibility maps.


Assuntos
Encéfalo , Imagem Ecoplanar , Imageamento Tridimensional , Esclerose Múltipla , Humanos , Imageamento Tridimensional/métodos , Esclerose Múltipla/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Imagem Ecoplanar/métodos , Adulto , Masculino , Feminino , Algoritmos , Pessoa de Meia-Idade , Mapeamento Encefálico/métodos , Processamento de Imagem Assistida por Computador/métodos , Interpretação de Imagem Assistida por Computador/métodos
6.
Public Health Nutr ; 27(1): e123, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38639113

RESUMO

OBJECTIVE: Most evidence supporting screening for undernutrition is for children aged 6-59 months. However, the highest risk of mortality and highest incidence of wasting occurs in the first 6 months of life. We evaluated relationships between neonatal anthropometric indicators, including birth weight, weight-for-age Z-score (WAZ), weight-for-length Z-score (WLZ), length-for-age Z-score (LAZ) and mid-upper arm circumference (MUAC) and mortality and growth at 6 months of age among infants in Burkina Faso. DESIGN: Data arose from a randomised controlled trial evaluating neonatal azithromycin administration for the prevention of child mortality. We evaluated relationships between baseline anthropometric measures and mortality, wasting (WLZ < -2), stunting (LAZ < -2) and underweight (WAZ < -2) at 6 months of age were estimated using logistic regression models adjusted for the child's age and sex. SETTING: Five regions of Burkina Faso. PARTICIPANTS: Infants aged 8-27 d followed until 6 months of age. RESULTS: Of 21 832 infants enrolled in the trial, 7·9 % were low birth weight (<2500 g), 13·3 % were wasted, 7·7 % were stunted and 7·4 % were underweight at enrolment. All anthropometric deficits were associated with mortality by 6 months of age, with WAZ the strongest predictor (WAZ < -2 to ≥ -3 at enrolment v. WAZ ≥ -2: adjusted OR, 3·91, 95 % CI, 2·21, 6·56). Low WAZ was also associated with wasting, stunting, and underweight at 6 months. CONCLUSIONS: Interventions for identifying infants at highest risk of mortality and growth failure should consider WAZ as part of their screening protocol.


Assuntos
Antropometria , Peso ao Nascer , Transtornos do Crescimento , Mortalidade Infantil , Magreza , Humanos , Burkina Faso/epidemiologia , Lactente , Masculino , Feminino , Recém-Nascido , Transtornos do Crescimento/epidemiologia , Transtornos do Crescimento/mortalidade , Magreza/epidemiologia , Magreza/mortalidade , Estatura , Recém-Nascido de Baixo Peso , Azitromicina/administração & dosagem , Azitromicina/uso terapêutico , Desenvolvimento Infantil , Síndrome de Emaciação/epidemiologia , Síndrome de Emaciação/mortalidade , Peso Corporal , Modelos Logísticos
7.
EJNMMI Res ; 14(1): 33, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38558200

RESUMO

BACKGROUND: Accurate measurement of the arterial input function (AIF) is crucial for parametric PET studies, but the AIF is commonly derived from invasive arterial blood sampling. It is possible to use an image-derived input function (IDIF) obtained by imaging a large blood pool, but IDIF measurement in PET brain studies performed on standard field of view scanners is challenging due to lack of a large blood pool in the field-of-view. Here we describe a novel automated approach to estimate the AIF from brain images. RESULTS: Total body 18F-FDG PET data from 12 subjects were split into a model adjustment group (n = 6) and a validation group (n = 6). We developed an AIF estimation framework using wavelet-based methods and unsupervised machine learning to distinguish arterial and venous activity curves, compared to the IDIF from the descending aorta. All of the automatically extracted AIFs in the validation group had similar shape to the IDIF derived from the descending aorta IDIF. The average area under the curve error and normalised root mean square error across validation data were - 1.59 ± 2.93% and 0.17 ± 0.07. CONCLUSIONS: Our automated AIF framework accurately estimates the AIF from brain images. It reduces operator-dependence, and could facilitate the clinical adoption of parametric PET.

8.
Magn Reson Med ; 91(6): 2508-2518, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38321602

RESUMO

PURPOSE: The purpose of this study is to improve the image quality of diffusion-weighted images obtained with a single RF transmit channel 7 T MRI setup using time-resampled frequency-offset corrected inversion (TR-FOCI) pulses to refocus the spins in a twice-refocused spin-echo readout scheme. METHODS: We replaced the conventional Shinnar-Le Roux-pulses in the twice refocused diffusion sequence with TR-FOCI pulses. The slice profiles were evaluated in simulation and experimentally in phantoms. The image quality was evaluated in vivo comparing the Shinnar-Le Roux and TR-FOCI implementation using a b value of 0 and of 1000 s/mm2. RESULTS: The b0 and diffusion-weighted images acquired using the modified sequence improved the image quality across the whole brain. A region of interest-based analysis showed an SNR increase of 113% and 66% for the nondiffusion-weighted (b0) and the diffusion-weighted (b = 1000 s/mm2) images in the temporal lobes, respectively. Investigation of all slices showed that the adiabatic pulses mitigated B 1 + $$ {B}_1^{+} $$ inhomogeneity globally using a conventional single-channel transmission setup. CONCLUSION: The TR-FOCI pulse can be used in a twice-refocused spin-echo diffusion pulse sequence to mitigate the impact of B 1 + $$ {B}_1^{+} $$ inhomogeneity on the signal intensity across the brain at 7 T. However, further work is needed to address SAR limitations.


Assuntos
Algoritmos , Imagem de Difusão por Ressonância Magnética , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Imagens de Fantasmas
9.
Z Med Phys ; 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38336583

RESUMO

BACKGROUND: Emerging evidence suggests that traumatic brain injury (TBI) is a major risk factor for developing neurodegenerative disease later in life. Quantitative susceptibility mapping (QSM) has been used by an increasing number of studies in investigations of pathophysiological changes in TBI. However, generating artefact-free quantitative susceptibility maps in brains with large focal lesions, as in the case of moderate-to-severe TBI (ms-TBI), is particularly challenging. To address this issue, we utilized a novel two-pass masking technique and reconstruction procedure (two-pass QSM) to generate quantitative susceptibility maps (QSMxT; Stewart et al., 2022, Magn Reson Med.) in combination with the recently developed virtual brain grafting (VBG) procedure for brain repair (Radwan et al., 2021, NeuroImage) to improve automated delineation of brain areas. We used QSMxT and VBG to generate personalised QSM profiles of individual patients with reference to a sample of healthy controls. METHODS: Chronic ms-TBI patients (N = 8) and healthy controls (N = 12) underwent (multi-echo) GRE, and anatomical MRI (MPRAGE) on a 3T Siemens PRISMA scanner. We reconstructed the magnetic susceptibility maps using two-pass QSM from QSMxT. We then extracted values of magnetic susceptibility in grey matter (GM) regions (following brain repair via VBG) across the whole brain and determined if they deviate from a reference healthy control group [Z-score < -3.43 or > 3.43, relative to the control mean], with the aim of obtaining personalised QSM profiles. RESULTS: Using two-pass QSM, we achieved susceptibility maps with a substantial increase in quality and reduction in artefacts irrespective of the presence of large focal lesions, compared to single-pass QSM. In addition, VBG minimised the loss of GM regions and exclusion of patients due to failures in the region delineation step. Our findings revealed deviations in magnetic susceptibility measures from the HC group that differed across individual TBI patients. These changes included both increases and decreases in magnetic susceptibility values in multiple GM regions across the brain. CONCLUSIONS: We illustrate how to obtain magnetic susceptibility values at the individual level and to build personalised QSM profiles in ms-TBI patients. Our approach opens the door for QSM investigations in more severely injured patients. Such profiles are also critical to overcome the inherent heterogeneity of clinical populations, such as ms-TBI, and to characterize the underlying mechanisms of neurodegeneration at the individual level more precisely. Moreover, this new personalised QSM profiling could in the future assist clinicians in assessing recovery and formulating a neuroscience-guided integrative rehabilitation program tailored to individual TBI patients.

10.
JAMA ; 331(6): 482-490, 2024 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-38349371

RESUMO

Importance: Repeated mass distribution of azithromycin has been shown to reduce childhood mortality by 14% in sub-Saharan Africa. However, the estimated effect varied by location, suggesting that the intervention may not be effective in different geographical areas, time periods, or conditions. Objective: To evaluate the efficacy of twice-yearly azithromycin to reduce mortality in children in the presence of seasonal malaria chemoprevention. Design, Setting, and Participants: This cluster randomized placebo-controlled trial evaluating the efficacy of single-dose azithromycin for prevention of all-cause childhood mortality included 341 communities in the Nouna district in rural northwestern Burkina Faso. Participants were children aged 1 to 59 months living in the study communities. Interventions: Communities were randomized in a 1:1 ratio to receive oral azithromycin or placebo distribution. Children aged 1 to 59 months were offered single-dose treatment twice yearly for 3 years (6 distributions) from August 2019 to February 2023. Main Outcomes and Measures: The primary outcome was all-cause childhood mortality, measured during a twice-yearly enumerative census. Results: A total of 34 399 children (mean [SD] age, 25.2 [18] months) in the azithromycin group and 33 847 children (mean [SD] age, 25.6 [18] months) in the placebo group were included. A mean (SD) of 90.1% (16.0%) of the censused children received the scheduled study drug in the azithromycin group and 89.8% (17.1%) received the scheduled study drug in the placebo group. In the azithromycin group, 498 deaths were recorded over 60 592 person-years (8.2 deaths/1000 person-years). In the placebo group, 588 deaths were recorded over 58 547 person-years (10.0 deaths/1000 person-years). The incidence rate ratio for mortality was 0.82 (95% CI, 0.67-1.02; P = .07) in the azithromycin group compared with the placebo group. The incidence rate ratio was 0.99 (95% CI, 0.72-1.36) in those aged 1 to 11 months, 0.92 (95% CI, 0.67-1.27) in those aged 12 to 23 months, and 0.73 (95% CI, 0.57-0.94) in those aged 24 to 59 months. Conclusions and Relevance: Mortality in children (aged 1-59 months) was lower with biannual mass azithromycin distribution in a setting in which seasonal malaria chemoprevention was also being distributed, but the difference was not statistically significant. The study may have been underpowered to detect a clinically relevant difference. Trial Registration: ClinicalTrials.gov Identifier: NCT03676764.


Assuntos
Antibacterianos , Azitromicina , Mortalidade da Criança , Malária , Humanos , Azitromicina/provisão & distribuição , Azitromicina/uso terapêutico , Burkina Faso/epidemiologia , Quimioprevenção/métodos , Quimioprevenção/estatística & dados numéricos , Mortalidade da Criança/tendências , Malária/epidemiologia , Malária/mortalidade , Malária/prevenção & controle , Antibacterianos/provisão & distribuição , Antibacterianos/uso terapêutico , Estações do Ano , Lactente , Pré-Escolar
11.
EJNMMI Res ; 14(1): 10, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38289518

RESUMO

BACKGROUND: The indirect method for generating parametric images in positron emission tomography (PET) involves the acquisition and reconstruction of dynamic images and temporal modelling of tissue activity given a measured arterial input function. This approach is not robust, as noise in each dynamic image leads to a degradation in parameter estimation. Direct methods incorporate into the image reconstruction step both the kinetic and noise models, leading to improved parametric images. These methods require extensive computational time and large computing resources. Machine learning methods have demonstrated significant potential in overcoming these challenges. But they are limited by the requirement of a paired training dataset. A further challenge within the existing framework is the use of state-of-the-art arterial input function estimation via temporal arterial blood sampling, which is an invasive procedure, or an additional magnetic resonance imaging (MRI) scan for selecting a region where arterial blood signal can be measured from the PET image. We propose a novel machine learning approach for reconstructing high-quality parametric brain images from histoimages produced from time-of-flight PET data without requiring invasive arterial sampling, an MRI scan, or paired training data from standard field-of-view scanners. RESULT: The proposed is tested on a simulated phantom and five oncological subjects undergoing an 18F-FDG-PET scan of the brain using Siemens Biograph Vision Quadra. Kinetic parameters set in the brain phantom correlated strongly with the estimated parameters (K1, k2 and k3, Pearson correlation coefficient of 0.91, 0.92 and 0.93) and a mean squared error of less than 0.0004. In addition, our method significantly outperforms (p < 0.05, paired t-test) the conventional nonlinear least squares method in terms of contrast-to-noise ratio. At last, the proposed method was found to be 37% faster than the conventional method. CONCLUSION: We proposed a direct non-invasive DL-based reconstruction method and produced high-quality parametric maps of the brain. The use of histoimages holds promising potential for enhancing the estimation of parametric images, an area that has not been extensively explored thus far. The proposed method can be applied to subject-specific dynamic PET data alone.

12.
EJNMMI Res ; 14(1): 1, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38169031

RESUMO

BACKGROUND: In parametric PET, kinetic parameters are extracted from dynamic PET images. It is not commonly used in clinical practice because of long scan times and the requirement for an arterial input function (AIF). To address these limitations, we designed an 18F-fluorodeoxyglucose (18F-FDG) triple injection dynamic PET protocol for brain imaging with a standard field of view PET scanner using a 24-min imaging window and an input function modeled using measurements from a region of interest placed over the left ventricle. METHODS: To test the protocol in 6 healthy participants, we examined the quality of voxel-based maps of kinetic parameters in the brain generated using the two-tissue compartment model and compared estimated parameter values with previously published values. We also utilized data from a 36-min validation imaging window to compare (1) the modeled AIF against the input function measured in the validation window; and (2) the net influx rate ([Formula: see text]) computed using parameter estimates from the short imaging window against the net influx rate obtained using Patlak analysis in the validation window. RESULTS: Compared to the AIF measured in the validation window, the input function estimated from the short imaging window achieved a mean area under the curve error of 9%. The voxel-wise Pearson's correlation between [Formula: see text] estimates from the short imaging window and the validation imaging window exceeded 0.95. CONCLUSION: The proposed 24-min triple injection protocol enables parametric 18F-FDG neuroimaging with noninvasive estimation of the AIF from cardiac images using a standard field of view PET scanner.

13.
PLoS Med ; 21(1): e1004345, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38261579

RESUMO

BACKGROUND: Antibiotic use during early infancy has been linked to childhood obesity in high-income countries. We evaluated whether a single oral dose of azithromycin administered during infant-well visits led to changes in infant growth outcomes at 6 months of age in a setting with a high prevalence of undernutrition in rural Burkina Faso. METHODS AND FINDINGS: Infants were enrolled from September 25, 2019, until October 22, 2022, in a randomized controlled trial designed to evaluate the efficacy of a single oral dose of azithromycin (20 mg/kg) compared to placebo when administered during well-child visits for prevention of infant mortality. The trial found no evidence of a difference in the primary endpoint. This paper presents prespecified secondary anthropometric endpoints including weight gain (g/day), height change (mm/day), weight-for-age Z-score (WAZ), weight-for-length Z-score (WLZ), length-for-age Z-score (LAZ), and mid-upper arm circumference (MUAC). Infants were eligible for the trial if they were between 5 and 12 weeks of age, able to orally feed, and their families were planning to remain in the study area for the duration of the study. Anthropometric measurements were collected at enrollment (5 to 12 weeks of age) and 6 months of age. Among 32,877 infants enrolled in the trial, 27,298 (83%) were followed and had valid anthropometric measurements at 6 months of age. We found no evidence of a difference in weight gain (mean difference 0.03 g/day, 95% confidence interval (CI) -0.12 to 0.18), height change (mean difference 0.004 mm/day, 95% CI -0.05 to 0.06), WAZ (mean difference -0.004 SD, 95% CI -0.03 to 0.02), WLZ (mean difference 0.001 SD, 95% CI -0.03 to 0.03), LAZ (mean difference -0.005 SD, 95% CI -0.03 to 0.02), or MUAC (mean difference 0.01 cm, 95% CI -0.01 to 0.04). The primary limitation of the trial was that measurements were only collected at enrollment and 6 months of age, precluding assessment of shorter-term or long-term changes in growth. CONCLUSIONS: Single-dose azithromycin does not appear to affect weight and height outcomes when administered during early infancy. TRIAL REGISTRATION: ClinicalTrials.gov NCT03676764.


Assuntos
Azitromicina , Obesidade Infantil , Criança , Lactente , Humanos , Azitromicina/efeitos adversos , Burkina Faso/epidemiologia , Aumento de Peso , Antibacterianos/efeitos adversos
14.
Ophthalmol Glaucoma ; 7(2): 148-156, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37611749

RESUMO

PURPOSE: To assess the diagnostic accuracy of anterior segment OCT (AS-OCT) screening for detecting gonioscopically narrow angles. DESIGN: Population-based cross-sectional study. PARTICIPANTS: A stratified random sample of individuals aged ≥ 60 years, selected from a door-to-door census performed in low-lying Nepal. TESTING: Participants underwent AS-OCT, posterior segment OCT, and intraocular pressure (IOP) testing in the community. Those meeting referral criteria in either eye were invited to have a comprehensive eye examination including gonioscopy. Referral criteria included (i) the lowest 2.5% of AS-OCT measurements, (ii) retinal OCT results suggestive of glaucomatous optic neuropathy, diabetic retinopathy, or age-related macular degeneration, and (iii) elevated IOP. MAIN OUTCOME MEASURES: Sensitivity and specificity of 5 semiautomated AS-OCT parameters relative to gonioscopically narrow angles, defined as the absence of visible trabecular meshwork for ≥ 180° on nonindentation gonioscopy. RESULTS: Of 17 656 people aged ≥ 60 years enumerated from 102 communities, 12 633 (71.6%) presented for AS-OCT testing. Referral was recommended for 697 participants based on AS-OCT criteria and 2419 participants based on other criteria, of which 858 had gonioscopy performed by a glaucoma specialist. Each of the 5 AS-OCT parameters offered good diagnostic information for predicting eyes with gonioscopically narrow angles, with areas under the receiver operating characteristic curve ranging from 0.85 to 0.89. The angle opening distance at 750 µm from the scleral spur (AOD750) provided the most diagnostic information, providing an optimal sensitivity of 87% (95% confidence interval [CI], 75%-96%) and specificity of 77% (71%-83%) at a cutpoint of 367 µm, and a sensitivity of 65% (95% CI, 54%-74%) when specificity was constrained to 90% (cutpoint, 283 µm). CONCLUSIONS: On AS-OCT, the AOD750 parameter detected approximately two-thirds of cases of gonioscopically narrow angles when test specificity was set to 90%. Although such a sensitivity may not be sufficient when screening solely for narrow angles, AS-OCT requires little additional effort if posterior segment OCT is already being performed and thus could provide incremental benefit when performing OCT-based screening. FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any materials discussed in this article.


Assuntos
Glaucoma de Ângulo Fechado , Glaucoma , Humanos , Tomografia de Coerência Óptica/métodos , Estudos Transversais , Glaucoma de Ângulo Fechado/diagnóstico , Malha Trabecular , Sensibilidade e Especificidade , Glaucoma/diagnóstico
15.
Eye (Lond) ; 38(5): 945-950, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37949975

RESUMO

BACKGROUND: South Asia is experiencing rapid urbanization, which may be changing the risk factor profile for ocular trauma. The objective of this study was to compare risk factors for traumatic corneal abrasions in rural versus urban Nepal, and to assess if any risk factors were associated with a poor outcome. METHODS: In a prospective, cross-sectional, community-based study performed as part of a cluster-randomized trial, community health workers from Nepal were trained to diagnose and treat traumatic corneal abrasions. Participants with an abrasion were invited to complete a risk factor survey. The main exposure variable was the object of eye injury, stratified by rural-urban residence. The main outcome measure was a lack of corneal healing after a three-day course of antimicrobials. RESULTS: Of 3657 participants diagnosed with a corneal abrasion, 2265 completed a survey. Eye trauma occurred most frequently during agricultural activities. The most common object of injury was vegetative matter, accounting for approximately 40% of injuries in rural, peri-urban, and urban communities. Wood injuries were more common in rural communities (24%) compared with urban or peri-urban communities (13%). Eye injury from an animal was more likely to result in a non-healing corneal abrasion after 3 days of treatment compared with other types of trauma (prevalence ratio 2.59, 95%CI 1.16-5.76). CONCLUSIONS: Health promotion activities for prevention of corneal ulcers in Nepal should focus on agricultural trauma in both rural and urban areas. Community members experiencing eye trauma from an animal may benefit from early referral to an eye clinic.


Assuntos
Lesões da Córnea , Humanos , Estudos Transversais , Nepal , Estudos Prospectivos , Fatores de Risco
16.
Cornea Open ; 2(3)2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38076595

RESUMO

Purpose: To evaluate the diagnostic accuracy of smartphone corneal photography in detecting corneal opacities in a community-based setting. Methods: A case-control, diagnostic accuracy study was nested in a cluster-randomized trial of a corneal ulcer prevention intervention in Nepal. Smartphone corneal photography was performed annually on community members self-reporting a potential risk factor for a corneal infection. Corneal photographs were graded for the presence or absence of an opacity. All cases with an opacity on smartphone photography and an equal number of controls were invited for a comprehensive eye examination with a slit lamp biomicroscope at an eye hospital. A mobile team visited participants unable to come to the hospital, conducting a limited examination with a penlight. Results: Of 1332 study participants (666 cases and 666 controls), 1097 had a penlight examination (535 cases and 562 controls) and 191 had a slit lamp examination (120 cases and 71 controls). When penlight examination was considered the reference standard, smartphone diagnosis of a corneal opacity had a positive predictive value (PPV) of 47% (95% confidence interval 43-52%) and negative predictive value (NPV) of 95% (93-97%). When slit lamp examination was considered the reference standard, the overall PPV and NPV were 71% (62-78%) and 80% (70-88%), respectively. The NPV was greater for detection of opacities > 1mm, estimated at 95% (90-98%). Conclusions: Corneal photography performed in a resource-limited community-based setting using a smartphone coupled to an external attachment had acceptable diagnostic accuracy for detection of corneal opacities large enough to be clinically meaningful.

18.
JAMA Netw Open ; 6(12): e2346840, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38100110

RESUMO

Importance: The MORDOR (Macrolides Oraux pour Réduire les Décès avec un Oeil sur la Résistance) trial demonstrated that mass azithromycin administration reduced mortality by 18% among children aged 1 to 59 months in Niger. The identification of high-risk subgroups to target with this intervention could reduce the risk of antimicrobial resistance. Objective: To evaluate whether distance to the nearest primary health center modifies the effect of azithromycin administration to children aged 1 to 59 months on child mortality. Design, Setting, and Participants: The MORDOR cluster randomized trial was conducted from December 1, 2014, to July 31, 2017; this post hoc secondary analysis was conducted in 2023 among 594 clusters (communities or grappes) in the Boboye and Loga departments in Niger. All children aged 1 to 59 months in eligible communities were evaluated. Interventions: Biannual (twice-yearly) administration of a single dose of oral azithromycin or matching placebo over 2 years. Main Outcomes and Measures: A population-based census was used to monitor mortality and person-time at risk (trial primary outcome). Community distance to a primary health center was calculated as kilometers between the center of each community and the nearest health center. Negative binomial regression was used to evaluate the interaction between distance and the effect of azithromycin on the incidence of all-cause mortality among children aged 1 to 59 months. Results: Between December 1, 2014, and July 31, 2017, a total of 594 communities were enrolled, with 76 092 children (mean [SD] age, 31 [2] months; 39 022 [51.3%] male) included at baseline, for a mean (SD) of 128 (91) children per community. Median (IQR) distance to the nearest primary health center was 5.0 (3.2-7.1) km. Over 2 years, 145 693 person-years at risk were monitored and 3615 deaths were recorded. Overall, mortality rates were 27.5 deaths (95% CI, 26.2-28.7 deaths) per 1000 person-years at risk in the placebo arm and 22.5 deaths (95% CI, 21.4-23.5 deaths) per 1000 person-years at risk in the azithromycin arm. For each kilometer increase in distance in the placebo arm, mortality increased by 5% (adjusted incidence rate ratio, 1.05; 95% CI, 1.03-1.07; P < .001). The effect of azithromycin on mortality varied significantly by distance (interaction P = .02). Mortality reduction with azithromycin compared with placebo was 0% at 0 km from the health center (95% CI, -19% to 17%), 4% at 1 km (95% CI, -12% to 17%), 16% at 5 km (95% CI, 7% to 23%), and 28% at 10 km (95% CI, 17% to 38%). Conclusions and Relevance: In this secondary analysis of a cluster randomized trial of mass azithromycin administration for child mortality, children younger than 5 years who lived farthest from health facilities appeared to benefit the most from azithromycin administration. These findings may help guide the allocation of resources to ensure that those with the least access to existing health resources are prioritized in program implementation. Trial Registration: ClinicalTrials.gov Identifier: NCT02047981.


Assuntos
Azitromicina , Academias de Ginástica , Criança , Masculino , Humanos , Adulto , Feminino , Azitromicina/uso terapêutico , Níger/epidemiologia , Administração Massiva de Medicamentos , Instalações de Saúde
19.
PLOS Glob Public Health ; 3(11): e0002559, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37967058

RESUMO

Recent evidence indicates mass azithromycin distribution reduces under-5 mortality. This intervention is being considered for child survival programs in high mortality sub-Saharan African settings. The delivery approach used in prior studies required a full-time census and distribution team, which is not feasible for most programs. To determine the optimal programmatic approach to delivery, this study aimed to compare treatment coverage, costs, and acceptability of different delivery approaches with existing community health workers (CHWs). This cluster-randomized trial included rural and peri-urban communities in Dosso, Niger (clinicaltrials.gov, NCT04774991). A random sample of 80 eligible communities was randomized 1:1 to biannual door-to-door or fixed-point delivery of oral azithromycin to children 1-59 months old over 1 year. Data analysts alone were masked given the nature of the intervention. The primary outcome was community-level treatment coverage defined as the number of children treated recorded by CHWs divided by the number of eligible children determined using a post-distribution census. Costs were monitored through routine administrative data collection and micro-costing. The census included survey questions on intervention acceptability among caregivers, community leaders, and CHWs. After randomization, 1 community was excluded due to inaccuracies in available administrative data, resulting in 39 communities receiving door-to-door delivery. At the second distribution, community-level mean treatment coverage was 105% (SD 44%) in the door-to-door arm and 92% (SD 20%) in the fixed-point arm (Mean difference 13%, 95% CI -2% to 28%, P-value = 0.08). The total cost per dose delivered was $1.91 in the door-to-door arm and $2.51 in the fixed-point arm. Indicators of acceptability were similar across stakeholder groups in both arms, with most respondents in each group indicating a preference for door-to-door. Overall, door-to-door delivery is the preferred approach to azithromycin distribution in this setting and might reach more children at a lower cost per dose delivered than fixed-point. Trial Registration: clinicaltrials.gov NCT04774991.

20.
Bull World Health Organ ; 101(12): 786-799, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38024247

RESUMO

Objective: To assess how the returns on investment from correcting refractive errors and cataracts in low- and middle-income countries compare with the returns from other global development interventions. Methods: We adopted two complementary approaches to estimate benefit-cost ratios from eye health investment. First, we systematically searched PubMed® and Web of Science™ on 14 August 2023 for studies conducted in low-and-middle-income countries, which have measured welfare impacts associated with correcting refractive errors and cataracts. Using benefit-cost analysis, we compared these impacts to costs. Second, we employed an economic modelling analysis to estimate benefit-cost ratios from eye health investments in India. We compared the returns from eye health to returns in other domains across global health and development. Findings: We identified 21 studies from 10 countries. Thirteen outcomes highlighted impacts from refractive error correction for school students. From the systematic review, we used 17 out of 33 outcomes for benefit-cost analyses, with the median benefit-cost ratio being 36. The economic modelling approach for India generated benefit-cost ratios ranging from 28 for vision centres to 42 for school eye screening, with an aggregate ratio of 31. Comparing our findings to the typical investment in global development shows that eye health investment returns six times more benefits (median benefit-cost ratio: 36 vs 6). Conclusion: Eye health investments provide economic benefits with varying degrees based on the intervention type and location. Our findings underline the importance of incorporating eye health initiatives into broader development strategies for substantial societal returns.


Assuntos
Catarata , Erros de Refração , Humanos , Análise Custo-Benefício , Investimentos em Saúde , Índia
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