New-Generation Low-Field Magnetic Resonance Imaging of Hip Arthroplasty Implants

alexandrossfakianakis shared this article with you from Inoreader New-Generation Low-Field Magnetic Resonance Imaging of Hip Arthroplasty Implants Using Slice Encoding for Metal Artifact Correction: First In Vitro Experience at 0.55 T and Comparison With 1.5 T via Investigative Radiology - Current Issue Objectives Despite significant progress, artifact-free visualization of the bone and soft tissues around hip arthroplasty implants remains an unmet clinical need. New-generation low-field magnetic resonance imaging (MRI) systems now include slice encoding for metal artifact correction (SEMAC), which may result in smaller metallic artifacts and better image quality than standard-of-care 1.5 T MRI. This study aims to assess the feasibility of SEMAC on a new-generation 0.55 T system, optimize the pulse protocol parameters, and compare the results with those of a standard-of-care 1.5 T MRI. Materials and Methods Titanium (Ti) and cobalt-chromium total hip arthroplasty implants embedded in a tissue-mimicking American Society for Testing and Materials gel phantom were evaluated using turbo spin echo, view angle tilting (VAT), and combined VAT and SEMAC (VAT + SEMAC) pulse sequences. To refine an MRI protocol at 0.55 T, the type of metal artifact reduction techniques and the effect of various pulse sequence parameters on metal artifacts were assessed through qualitative ranking of the images by 3 expert readers while taking measured spatial resolution, signal-to-noise ratios, and acquisition times into consideration. Signal-to-noise ratio efficiency and artifact size of the optimized 0.55 T protocols were compared with the 1.5 T standard and compressed-sensing SEMAC sequences. Results Overall, the VAT + SEMAC sequence with at least 6 SEMAC encoding steps for Ti and 9 for cobalt-chromium implants was ranked higher than other sequences for metal reduction (P View on Web

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Pharmacokinetics, Safety, and Efficacy of Gadopiclenol in Pediatric Patients Aged 2 to 17 Years

alexandrossfakianakis shared this article with you from Inoreader Pharmacokinetics, Safety, and Efficacy of Gadopiclenol in Pediatric Patients Aged 2 to 17 Years via Investigative Radiology - Current Issue Objectives The aim of this study was to evaluate the pharmacokinetic (PK) profile, safety, and efficacy of gadopiclenol, a new high-relaxivity gadolinium-based contrast agent, in children aged 2 to 17 years. Materials and Methods Children scheduled to undergo contrast-enhanced magnetic resonance imaging of the central nervous system (CNS cohort) or other organs (body cohort) were included sequentially into 3 age groups (12–17, 7–11, and 2–6 years). Gadopiclenol was administered at the dose of 0.05 mmol/kg. A sparse sampling approach was applied, with 4 blood samples per child collected up to 8 hours postinjection. Population PK modeling was used for the analysis, including the CNS cohort and adult subjects from a previous study. Adverse events were recorded, and efficacy was assessed for all children. Results Eighty children were included, 60 in the CNS cohort and 20 in the body cohort. The 2-compartment model with linear elimination from the central compartment developed in adults was also suitable for children. Pharmacokinetic parameters were very similar between adults and children. Terminal elimination half-life was 1.82 hours for adults and 1.77 to 1.29 hours for age groups 12–17 to 2–6 years. The median clearance ranged from 0.08 L/h/kg in adults and 12–17 years to 0.12 L/h/kg in 2–6 years. The median central and peripheral volumes of distribution were 0.11 to 0.12 L/kg and 0.06 L/kg, respectively, for both adults and children. Simulations of plasma concentrations showed minor differences, and median area under the curve was 590 mg·h/L for adults and 582 to 403 mg·h/L for children. Two patients (2.5%) experienced nonserious adverse events considered related to gadopiclenol: a mild QT interval prolongation and a moderate maculopapular rash. Despite the limited number of pat ients, this study showed that gadopiclenol improved lesion detection, visualization, and diagnostic confidence. Conclusions The PK profile of gadopiclenol in children aged 2 to 17 years was similar to that observed in adults. Thus, there is no indication for age-based dose adaptation, and comparable plasma gadopiclenol concentrations are predicted to be achieved with body weight–based dosing in this population. Gadopiclenol at 0.05 mmol/kg seems to have a good safety profile in these patients and could improve lesion detection and visualization, therefore providing better diagnostic confidence. View on Web

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From Dose Reduction to Contrast Maximization: Can Deep Learning Amplify the Impact of Contrast Media on Brain Magnetic Resonance Image Quality? A Reader Study

alexandrossfakianakis shared this article with you from Inoreader From Dose Reduction to Contrast Maximization: Can Deep Learning Amplify the Impact of Contrast Media on Brain Magnetic Resonance Image Quality? A Reader Study via Investigative Radiology - Current Issue Objectives The aim of this study was to evaluate a deep learning method designed to increase the contrast-to-noise ratio in contrast-enhanced gradient echo T1-weighted brain magnetic resonance imaging (MRI) acquisitions. The processed images are quantitatively evaluated in terms of lesion detection performance. Materials and Methods A total of 250 multiparametric brain MRIs, acquired between November 2019 and March 2021 at Gustave Roussy Cancer Campus (Villejuif, France), were considered for inclusion in this retrospective monocentric study. Independent training (107 cases; age, 55 ± 14 years; 58 women) and test (79 cases; age, 59 ± 14 years; 41 women) samples were defined. Patients had glioma, brain metastasis, meningioma, or no enhancing lesion. Gradient echo and turbo spin echo with variable flip angles postcontrast T1 sequences were acquired in all cases. For the cases that formed the training sample, "low-dose" postcontrast gradient echo T1 images using 0.025 mmol/kg injections of contrast agent were also acquired. A deep neural network was trained to synthetically enhance the low-dose T1 acquisitions, taking standard-dose T1 MRI as reference. Once trained, the contrast enhancement network was used to process the test gradient echo T1 images. A read was then performed by 2 experienced neuroradiologist s to evaluate the original and processed T1 MRI sequences in terms of contrast enhancement and lesion detection performance, taking the turbo spin echo sequences as reference. Results The processed images were superior to the original gradient echo and reference turbo spin echo T1 sequences in terms of contrast-to-noise ratio (44.5 vs 9.1 and 16.8; P 0.99). The same effect was observed when considering all lesions larger than 5 mm: sensitivity increased from 70% to 85% (P View on Web

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Strategies for Evaluating Anosmia Therapeutics in the COVID-19 Era

alexandrossfakianakis shared this article with you from Inoreader Strategies for Evaluating Anosmia Therapeutics in the COVID-19 Era via JAMA Otolaryngology–Head & Neck Surgery Online First Two studies in this issue of JAMA Otolaryngology–Head & Neck Surgery evaluate the use of nasal theophylline, a phosphodiesterase inhibitor that may promote neural olfactory signaling and recovery for postviral olfactory dysfunction (OD). The first, a dose-modification Research Letter by Lee et al was conducted in patients with non-COVID-19–related hyposmia or anosmia secondary to viral infection and confirmed by the objective University of Pennsylvania Smell Identification Test. This open-label, dose-escalation trial provides an educational description of how to evaluate the appropriate dose for an emerging pharmacologic intervention. Specifically, the authors identified 400 mg of theophylline twice daily as a tolerated dosage. This was calculated as an equivalent oral dose of 20 mg. A phase 2 pilot study by Gupta et al was desig ned using this valuable information. Patients with suspected COVID-19–related OD completed the University of Pennsylvania Smell Identification Test and were randomized to either theophylline or placebo nasal irrigations for 6 weeks. This study was inconclusive regarding the clinical benefit of theophylline nasal irrigations, although there was suggested improvement by subjective assessments. The authors acknowledge several limitations, including small sample size, the virtual nature of the study design and subsequent inability to conduct endoscopic nasal examinations, lack of information regarding participant COVID-19 vaccination status, lack of polymerase chain reaction–confirmed COVID-19 infection, and short-term participant follow-up. These acknowledgments are justified, and many can be overcome in subsequent studies with adequate funding and time. However, the heterogeneous nature of COVID-19 and associated research make this area of work particularly challenging. Herein, we propose several approaches to improve the rigor of OD research in the COVID-19 era. View on Web

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Safety of High-Dose Nasal Theophylline Irrigation in the Treatment of Postviral Olfactory Dysfunction

alexandrossfakianakis shared this article with you from Inoreader Safety of High-Dose Nasal Theophylline Irrigation in the Treatment of Postviral Olfactory Dysfunction via JAMA Otolaryngology–Head & Neck Surgery Online First This case series aims to determine the maximum tolerable dose of theophylline delivered via high-volume, low-pressure nasal saline irrigation for treatment of postviral olfactory dysfunction. View on Web

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Surgeon Thyroidectomy Case Volume Impacts Disease‐free Survival in the Management of Thyroid Cancer

alexandrossfakianakis shared this article with you from Inoreader Surgeon Thyroidectomy Case Volume Impacts Disease‐free Survival in the Management of Thyroid Cancer via The Laryngoscope In this population-based cohort study involving 37,233 thyroidectomies performed in Ontario, Canada between 1993 and 2017, we found both high-volume surgeons and hospitals to be predictors of better disease-free survival (DFS) in patients with well-differentiated thyroid cancer. DFS is higher among surgeons performing more than 40 thyroidectomies a year. Objectives To assess the association between surgeons thyroidectomy case volume and disease-free survival (DFS) for patients with well-differentiated thyroid cancer (WDTC). A secondary objective was to assess a surgeon volume cutoff to optimize outcomes in those with WDTC. We hypothesized that surgeon volume will be an important predictor of DFS in patients with WDTC after adjusting for hospital volume and sociodemographic and clinical factors. Methods In this retrospective population-based cohort study, we identified WDTC patients in Ontario, Canada, who underwent thyroidectomy confirmed by both hospital-level and surgeon-level administrative data between 1993 and 2017 (N = 37,233). Surgeon and hospital volumes were calculated based on number of cases performed in the year prior by the physician and at an institution performing each case, respectively and divided into quartiles. A multilevel hierarchical Cox regression model was used to estimate the effect of volume on DFS. Results A crude model without patient or treatment characteristics demonstrated that both higher surgeon volume quartiles (p < 0.001) and higher hospital volume quartiles (p < 0.001) were associated with DFS. After controlling for clustering and patient/treatment covariates and hospital volume, moderately low (18–39/year) and low (0–17/year) volume surgeons (hazard ratios [HR]: 1.23, 95% confidence interval [CI]: 1.09–1.39 and HR: 1.34, 95% CI: 1.17–1.53 respectively) remained an independent statistically significant negative predictor of DFS. Conclusion Both high-volume surgeons and hospitals are predictors of better DFS in patients with WDTC. DFS is higher among surgeons performing more than 40 thyroidectomies a year. Level of Evidence 3 Laryngoscope, 2022 View on Web

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Characterizing Pediatric Bilateral Vocal Fold Dysfunction: Analysis with the Pediatric Health Information System Database

alexandrossfakianakis shared this article with you from Inoreader Characterizing Pediatric Bilateral Vocal Fold Dysfunction: Analysis with the Pediatric Health Information System Database via The Laryngoscope This database study represents the largest cohort analysis to date characterizing bilateral vocal fold dysfunction. The majority of pediatric patients with bilateral vocal fold dysfunction (BVFD) have a complex chronic condition, with respiratory conditions being the most common followed by gastrointestinal conditions. Prognostic indicators of improved hospital survival include gastrointestinal comorbidities and presence of tracheostomy. Objectives The purpose of this study was to characterize pediatric bilateral vocal fold dysfunction and to examine the overall inpatient mortality. Methods Retrospective cohort analysis. Data from the Pediatric Health Information System was gathered for all pediatric patients with a diagnosis of bilateral vocal fold dysfunction between January 2008 and September 2020. Univariate and multivariate analyses were performed using Cox proportional hazard models. Results 2395 patients accounted for 4799 hospitalizations with bilateral vocal fold dysfunction. Inpatient mortality occurred in 2.9% of the study sample. Chiari 2 was found in 2.8% of patients. The most common associated diagnoses were related to comorbid respiratory conditions (61.1%). The median adjusted ratio of cost to charges was $76,569. Aspiration was noted in 28 patients (1.2%). Gastrostomy was performed in 607 patients (25.3%). Tracheostomy was performed in 27% of patients. The overall 90-day readmission rate was 61%. On multivariate analysis, prognostic factors associated with increased hospital survival include gastrointestinal comorbidities (hazard ratio [HR]: 0.29; 95% confidence interval [CI]: 0.18–0.49) and tracheostomy (HR: 0.21; 95% CI: 0.12–0.37). Conclusion This database study represents the largest cohort analysis to date characterizing bilateral vocal fold dysfunction. Favorable prognostic indicators of overall hospital survival include gastrointestinal comorbidities and the presence of tracheostomy. Tracheostomy is associated with an increase in hospital costs, comorbidities, gastrostomy tube placement, and Chiari diagnosis. Level of Evidence 4 Laryngoscope, 2022 View on Web

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