Πέμπτη 10 Νοεμβρίου 2022

Cetuximab-Based vs Carboplatin-Based Chemoradiotherapy for Patients With Head and Neck Cancer

alexandrossfakianakis shared this article with you from Inoreader
This cohort study compares survival with cetuximab-based and carboplatin-based chemoradiotherapy in locally advanced head and neck squamous cell carcinoma.
View on Web

Assessment of Fat Fractions in the Tongue, Soft Palate, Pharyngeal Wall, and Parapharyngeal Fat Pad by the GOOSE and DIXON Methods

alexandrossfakianakis shared this article with you from Inoreader
imageObjective The 2-point DIXON method is widely used to assess fat fractions (FFs) in magnetic resonance images (MRIs) of the tongue, pharyngeal wall, and surrounding tissues in patients with obstructive sleep apnea (OSA). However, the method is semiquantitative and is susceptible to B0 field inhomogeneities and R2* confounding factors. Using the method, although several studies have shown that patients with OSA have increased fat deposition around the pharyngeal cavity, conflicting findings was also reported in 1 study. This discrepancy necessitates that we examine the FF estimation method used in the earlier studies and seek a more accurate method to measure FFs. Materials and Methods We examined the advantages of using the GOOSE (globally optimal surface estimation) method to replace the 2-point DIXON method for quantifying fat in the tongue and surrounding tissues on MRIs. We first used phantoms with known FFs (true FFs) to validate the GOOSE method and examine the errors in the DIXON method. Then, we compared the 2 methods in the tongue, soft palate, pharyngeal wall, and parapharyngeal fat pad of 63 healthy participants to further assess the errors caused by the DIXON method. Six participants were excluded from the comparison of the tongue FFs because of technical failures. Paired Student t tests were performed on FFs to detect significant differences between the 2 methods. All measures were obtained using 3 T Siemens MRI scanners. Results In the phantoms, the FFs measured by GOOSE agreed with the true FF, with only a 1.2% mean absolute error. However, the same measure by DIXON had a 10.5% mean absolute error. The FFs obtained by DIXON were significantly lower than those obtained by GOOSE (P
View on Web

Ultra-High-Resolution Coronary CT Angiography With Photon-Counting Detector CT: Feasibility and Image Characterization

alexandrossfakianakis shared this article with you from Inoreader
imageObjectives The aim of this study was to evaluate the feasibility and quality of ultra-high-resolution coronary computed tomography angiography (CCTA) with dual-source photon-counting detector CT (PCD-CT) in patients with a high coronary calcium load, including an analysis of the optimal reconstruction kernel and matrix size. Materials and Methods In this institutional review board–approved study, 20 patients (6 women; mean age, 79 ± 10 years; mean body mass index, 25.6 ± 4.3 kg/m2) undergoing PCD-CCTA in the ultra-high-resolution mode were included. Ultra-high-resolution CCTA was acquired in an electrocardiography-gated dual-source spiral mode at a tube voltage of 120 kV and collimation of 120 × 0.2 mm. The field of view (FOV) and matrix sizes were adjusted to the resolution properties of the individual reconstruction kernels using a FOV of 200 × 200 mm2 or 150 × 150 mm2 and a matrix size of 512 × 512 pixels or 1024 × 1024 pixels, respectively. Images were reconstructed using vascular kernels of 8 sharpness levels (Bv40, Bv44, Bv56, Bv60, Bv64, Bv72, Bv80, and Bv89), using quantum iterative reconstruction (QIR) at a strength level of 4, and a slice thickness of 0.2 mm. Images with the Bv40 kernel, QIR at a strength level of 4, and a slice thickness of 0.6 mm served as the reference. Image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), vessel sharpness, and blooming artifacts were quantified. For subjective image quality, 2 blinded readers evaluated image noise and delineation of coronary artery plaques and the adjacent vessel lumen using a 5-point discrete visual scale. A phantom scan served to characterize image noise texture by calculating the noise power spectrum for every reconstruction kernel. Results Maximum spatial frequency (fpeak) gradually shifted to higher values for reconstructions with the Bv40 to Bv64 kernel (0.15 to 0.56 mm−1), but not for reconstructions with the Bv72 to Bv89 kernel. Ultra-high-resolution CCTA was feasible in all patients (median calcium score, 479). In patients, reconstructions with the Bv40 kernel and a slice thickness of 0.6 mm showed largest blooming artifacts (55.2% ± 9.8%) and lowest vessel sharpness (477.1 ± 73.6 ΔHU/mm) while achieving highest SNR (27.4 ± 5.6) and CNR (32.9 ± 6.6) and lowest noise (17.1 ± 2.2 HU). Considering reconstructions with a slice thickness of 0.2 mm, image noise, SNR, CNR, vessel sharpness, and blooming artifacts significantly differed across kernels (all P's
View on Web

Deep Learning-Enhanced Parallel Imaging and Simultaneous Multislice Acceleration Reconstruction in Knee MRI

alexandrossfakianakis shared this article with you from Inoreader
imageObjectives This study aimed to examine various combinations of parallel imaging (PI) and simultaneous multislice (SMS) acceleration imaging using deep learning (DL)-enhanced and conventional reconstruction. The study also aimed at comparing the diagnostic performance of the various combinations in internal knee derangement and provided a quantitative evaluation of image sharpness and noise using edge rise distance (ERD) and noise power (NP), respectively. Materials and Methods The data from adult patients who underwent knee magnetic resonance imaging using various DL-enhanced acquisitions between June 2021 and January 2022 were retrospectively analyzed. The participants underwent conventional 2-fold PI and DL protocols with 4- to 8-fold acceleration imaging (P2S2 [2-fold PI with 2-fold SMS], P3S2, and P4S2). Three readers evaluated the internal knee derangement and the overall image quality. The diagnostic performance was calculated using consensus reading as a standard reference, and we conducted comparative evaluations. We calculated the ERD and NP for quantitative evaluations of image sharpness and noise, respectively. Interreader and intermethod agreements were calculated using Fleiss κ. Results A total of 33 patients (mean age, 49 ± 19 years; 20 women) were included in this study. The diagnostic performance for internal knee derangement and the overall image quality were similar among the evaluated protocols. The NP values were significantly lower using the DL protocols than with conventional imaging (P 0.12). Interreader and intermethod agreements were moderate-to-excellent (κ = 0.574–0.838) and good-to-excellent (κ = 0.755–1.000), respectively. In addition, the mean acquisition time was reduced by 47% when using DL with P2S2, by 62% with P3S2, and by 71% with P4S2, compared with conventional P2 imaging (2 minutes and 55 seconds). Conclusions The combined use of DL-enhanced 8-fold acceleration imaging (4-fold PI with 2-fold SMS) showed comparable performance with conventional 2-fold PI for the evaluation of internal knee derangement, with a 71% reduction in acquisition time.
View on Web

Τετάρτη 9 Νοεμβρίου 2022

Obesity-related SNPs and weight gain following first-line antiretroviral therapy

alexandrossfakianakis shared this article with you from Inoreader

cid_ogimage.png

Abstract
Background
We studied the association of obesity-related SNPs (OR-SNPs) with weight gain after antiretroviral therapy (ART) in people with HIV (PWH).
Methods
Participants were ART-naïve PWH from the Spanish HIV Research Cohort who started ART from 2014 onwards and had blood/DNA deposited in the cohort Biobank. The primary outcome was change in weight at 96 weeks after starting ART. We genotyped 14 OR-SNPs from a meta-analysis of GWAS body mass index (B MI) loci. Changes over time in weight and BMI were studied using adjusted linear mixed models (A-LMM).
Results
A total of 1,021 PWH were included. The mean weight gain over 96 weeks was 2.90 (95% CI: 2.54–3.26) Kg. Factors associated with higher weight gain were female sex, birth in Sub-Saharan Africa, prior AIDS, CD4+ < 200 cells/uL, HIV-RNA > 100,000 copies/mL, negative HCV serology, and use of tenofovir alafenamide. A significant association was found between ZC3H4 rs3810291 GG genotype and BCDIN3D/FAIM2 rs7138803 GG genotypes polymorphisms and weight and BMI increase. The estimated adjusted mean (SE) of weight gains were 4.26 (0.56) Kg in ZC3H4 rs3810291 GG carriers and 2.66 (0.19) Kg in AA/AG carriers (P = 0.007). Likewise, the estimated means (SE) weight gain at 96 weeks were 3.35 (0.29) Kg in BCDIN3D/FAIM2 rs7138803 GG carriers and 2.51 (0.24) Kg in AG/AA carriers (P = 0.020).
Conclusions
Genetic factors may play a role in weight gain after ART initiation. Further work is needed to replicate our findings and understand how the identified SNPs lead to higher weight gain in this context.
View on Web

Maternal Antibody Response and Transplacental Transfer Following SARS-CoV-2 Infection or Vaccination in Pregnancy

alexandrossfakianakis shared this article with you from Inoreader

cid_ogimage.png

Abstract
Background
Pregnant persons are at increased risk of severe COVID-19 and adverse obstetric outcomes. Understanding maternal antibody response, duration, and transplacental transfer after SARS-CoV-2 infection and COVID-19 vaccination is important to inform public health recommendations.
Methods
This prospective observational cohort study included 351 pregnant people who had SARS-CoV-2 infection or COVID-19 vaccination during pregnancy. IgG and IgM to SAR S-CoV-2 S1 receptor binding domain were measured in maternal and cord blood. Antibody levels and transplacental transfer ratios were compared across 1) disease severity for those with SARS-CoV-2 infection and 2) infection versus vaccination.
Results
There were 252 individuals with SARS-CoV-2 infection and 99 who received COVID-19 vaccination during pregnancy. Birthing people with more severe SARS-CoV-2 infection had higher maternal and cord blood IgG levels (p = 0.0001, p = 0.0001). Median IgG transfer ratio was 0.87-1.2. Maternal and cord blood IgG were higher after vaccination than infection (p = 0.001, p = 0.001). Transfer ratio was higher after 90 days in the vaccinated group (p < 0.001). Modeling showed higher amplitude and half-life of maternal IgG following vaccination (p < 0.0001). There were no significant differences by fetal sex.
Conclusions
COVID-19 vaccination in pregnancy leads to higher and longer lasting maternal IgG le vels, higher cord blood IgG, and higher transfer ratio after 90 days compared to SARS-CoV-2 infection. Greater infection severity leads to higher maternal and cord blood antibodies. Maternal IgG decreases over time following both vaccination and infection, reinforcing the importance of vaccination, even after infection, and vaccine boosters for pregnant patients.
View on Web

Radiomics‐based machine learning for the diagnosis of lymph node metastases in patients with head and neck cancer: Systematic review

alexandrossfakianakis shared this article with you from Inoreader

Abstract

Machine learning (ML) is increasingly used to detect lymph node (LN) metastases in head and neck (H&N) carcinoma. We systematically reviewed the literature on radiomic-based ML for the detection of pathological LNs in H&N cancer. A systematic review was conducted in PubMed, EMBASE, and the Cochrane Library. Baseline study characteristics and methodological quality items (modeling, performance evaluation, clinical utility, and transparency items) were extracted and evaluated. The qualitative synthesis is presented using descriptive statistics. Seven studies were included in this study. Overall, the methodological quality items were generally favorable for modeling (57% of studies). The studies were mostly unsuccessful in terms of transparency (85.7%), evaluation of clinical utility (71.3%), and assessment of generalizability employing independent or external validation (72.5%). ML may be able to predict LN metastases in H&N cancer. Further studies are warranted to impro ve the generalizability assessment, clinical utility evaluation, and transparency items.

View on Web