Search

Ebstein's anomaly of the tricuspid valve (TV) is a congenital cardiac malformation of the tricuspid valve (TV) and right ventricle (RV) characterized by downward displacement of the functional annulus usually involving septal and inferior leaflets. Ebstein's anatomical spectrum is highly variable. This anatomical study aimed to unravel the morphogenetic mechanisms underlying this variability. Forty-two hearts exhibiting Ebstein anomaly from the Reference Center for Complex Congenital Heart Defects (CHD) collection were macroscopically analysed: 28 isolated and 14 associated with another CHD. Tricuspid leaflets, right ventricle (RV), and associated lesions were analysed. Measurements were related to fetal heart reference values according to gestational age. Specimens were classified depending on the distal insertion of the anterior leaflet: linear, hyphenated or focal. Among isolated Ebstein hearts, distal insertion of the anterior leaflet was linear in 36%, hyphenated in 29% and focal in 36%. Linear insertion was always associated with anterior TV orifice and absent inferior leaflet, with absent septal leaflet in 80%. Atrialisation (thin, paper-like, inferior RV wall) was found in 90% of the linear forms and 37.5% of the hyphenated forms, which were associated with various degrees of inferior and septal leaflets non-delaminationanomalies. In focal forms, only the septal leaflet was involved, and there was no atrialisation. Ventricular septal defect was found in 3 specimens, Uhl-like RV anterior wall in 2, including 1 with left ventricle non compaction. Associated Ebstein anomalies were predominantly found in pulmonary atresia with intact ventricular septum; there was no atrialisation and septal leaflet only was involved. Ebstein anomaly corresponds to an arrest in TV development, early in linear forms, late in focal forms, intermediate in hyphenated forms. Atrialisation was always associated with absent inferior leaflet, underlining developmental interaction between endocardial cushions and myocardium at the RV inferior wall. [ABSTRACT FROM AUTHOR]

Pulmonary atresia with intact ventricular septum (PA-IVS) means pulmonary valvar atresia without a ventricular septal defect (VSD). In PA-IVS, the right ventricle (RV) appears externally normal in size but the internal cavity is hypoplastic with major wall hypertrophy. Histology reveals myocardial disarray and endocardial fibroelastosis. The leaflets of the pulmonary valve are present but fused indicating an acquired lesion during fetal life. The files of all children with PA-IVS in our institution between 1981 and 2023 were reviewed, using a data warehouse to look for associated VSD. Patients with Ebstein anomaly and pulmonary atresia were excluded. When available, echocardiographic examinations were reviewed. One patient had severe coronary arterial anomaly leading to death and autopsy. The total cohort included 300 consecutive patients. Among those, we found 8 children with an associated VSD (2.6% of the cohort). According to the IPCCC-ICD11 nomenclature, the VSD was central perimembranous in 3, muscular in 4, outlet in 1. In this last patient, autopsy revealed a hypoplastic but not malaligned outlet septum, without aortic overriding, which discarded the diagnosis of tetralogy of Fallot (Fig. 1). Paradoxically, the presence of a VSD is compatible with diagnosis of PA-IVS. This rare association cannot be classified as "PA-VSD": this last term should be reserved to extreme forms of tetralogy of Fallot, associating outlet VSD, anteriorly malaligned outlet septum, overriding aorta and PA. Conversely, PA-IVS may be due to a RV myocardial disease, leading to a diminutive RV cavity, tricuspid valve hypoplasia and progressive fusion of the pulmonary leaflets leading to atresia. The anatomic type of VSD, muscular and perimembranous, and their rarity, are in favor of an incidental association. The imprecise term "PA-IVS" does not reflect the defect's anatomy and pathogenesis. It should then be modified, as it is crucial to use an accurate terminology to better describe congenital heart defects. [ABSTRACT FROM AUTHOR]

Ultra-high dose rate external beam radiotherapy (UHDR-RT) uses dose rates of several tens to thousands of Gy/s, compared with the dose rate of the order of a few Gy/min for conventional radiotherapy techniques, currently used in clinical practice. The use of such dose rate is likely to improve the therapeutic index by obtaining a radiobiological effect, known as the "FLASH" effect. This would maintain tumor control while enhancing tissues protection. To date, this effect has been achieved using beams of electrons, photons, protons, and heavy ions. However, the conditions required to achieve this "FLASH" effect are not well defined, and raise several questions, particularly with regard to the definition of the prescription, including dose fractionation, irradiated volume and the temporal structure of the pulsed beam. In addition, the dose delivered over a very short period induces technical challenges, particularly in terms of detectors, which must be mastered to guarantee safe clinical implementation. IRSN has carried out an in-depth literature review of the UHDR-RT technique, covering various aspects relating to patient radiation protection: the radiobiological mechanisms associated with the FLASH effect, the used temporal structure of the UHDR beams, accelerators and dose control, the properties of detectors to be used with UHDR beams, planning, clinical implementation, and clinical studies already carried out or in progress., (Copyright © 2024 Société française de radiothérapie oncologique (SFRO). Published by Elsevier Masson SAS. All rights reserved.)

Objective: Thyroid cancers are on the rise, but the associated vital prognosis and long-term survival rates are very good. Therefore, treated patients' quality of life and psychological well-being are important considerations. The treatment usually involves surgery and radioactive iodine (radioiodine) ablation. This study aims to investigate potential effects of radioiodine ablation therapy on health-related quality of life, anxiety and depression symptoms, and nutritional status at 6 months post-therapy., Methods: This study included 136 patients diagnosed with thyroid cancer. Absorbed doses to the salivary glands were estimated from dosimeters worn by patients. Patient health-related quality of life, psychological status and nutritional status were assessed before and 6 months after therapy using standardized questionnaires (including SF-36, Hospital Anxiety and Depression (HAD) scale). Statistical analyses included random-effects logistic and linear regressions adjusted for potential confounders., Results: While no significant association was found between radioiodine exposure and anxiety or depression symptoms, or nutritional status, a significant increase in the SF-36 role physical sub- score was observed in relation with the salivary gland dose (β= 6.54, 95%CI 2.71;10.36 for a 1-Gy increase)., Conclusions: The findings suggest an improved physical health-related quality of life, namely reduced pain and functional impairment, 6 months after radioiodine therapy in thyroid cancer patients. No significant association was found between radioiodine exposure and mental health-related quality of life, anxiety or depression scores nor nutritional status. This study does not provide any evidence that radioiodine therapy has a potentially adverse effect on patient health-related quality of life., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Background: Risk management programs targeting women with genetic predispositions to breast cancer (BC), eg, BRCA1 and BRCA2, are effective assuming full adherence with the program protocol. However, high risk to BC in women and equal access to care may not result in high and uniform adherence with the program., Objective: To elucidate factors influencing adherence with screening program in women with genetic predispositions to BC., Material and Methods: We retrieved data from a multicenter pathogenic-related BC surveillance program across 4 French regions. We used multilevel logistic modeling to analyze factors of adherence with the program, with "on-time" or postponed screening as the dependent variable., Results: Seven hundred and seventy-eight participants were followed for a 4.7-year median. We observed 2796 annual screening rounds and 5.4% postponed rounds with a 6-month margin. Women with prevalent BC and carriers of BRCA1 and BRCA2 mutations did not have on-time annual screenings any more than women low cancer risk. Better adherence was observed with screenings after the 2nd round, with higher total number of rounds. Having one or more recalls was significantly associated with worse adherence. No contextual factors affected adherence. Furthermore, postponed rounds increased between 2018 and 2020 compared to 2015 and 2017., Conclusion: Having a higher BC risk status does not result in better adherence to the risk management program. However, factors directly related to screening rounds reduced postponements. Future research should address the benefits of screening-related organizational factors that contribute to adherence improvement., (© The Author(s) 2024. Published by Oxford University Press.)

Background: In order to ensure adequate radiation protection of critical groups such as staff, caregivers and the general public coming into proximity of nuclear medicine (NM) patients, it is necessary to consider the impact of the radiation emitted by the patients during their stay at the hospital or after leaving the hospital. Current risk assessments are based on ambient dose rate measurements in a single position at a specified distance from the patient and carried out at several time points after administration of the radiopharmaceutical to estimate the whole-body retention. The limitations of such an approach are addressed in this study by developing and validating a more advanced computational dosimetry approach using Monte Carlo (MC) simulations in combination with flexible and realistic computational phantoms and time activity distribution curves from reference biokinetic models., Results: Measurements of the ambient dose rate equivalent Ḣ * (10) at 1 m from the NM patient have been successfully compared against MC simulations with 5 different codes using the ICRP adult reference computational voxel phantoms, for typical clinical procedures with 99m Tc-HDP/MDP, 18 FDG and Na 131 I. All measurement data fall in the 95% confidence intervals, determined for the average simulated results. Moreover, the different MC codes (MCNP-X, PHITS, GATE, GEANT4, TRIPOLI-4®) have been compared for a more realistic scenario where the effective dose rate Ė of an exposed individual was determined in positions facing and aside the patient model at 30 cm, 50 cm and 100 cm. The variation between codes was lower than 8% for all the radiopharmaceuticals at 1 m, and varied from 5 to 16% for the face-to face and side-by-side configuration at 30 cm and 50 cm. A sensitivity study on the influence of patient model morphology demonstrated that the relative standard deviation of Ḣ * (10) at 1 m for the range of included patient models remained under 16% for time points up to 120 min post administration., Conclusions: The validated computational approach will be further used for the evaluation of effective dose rates per unit administered activity for a variety of close-contact configurations and a range of radiopharmaceuticals as part of risk assessment studies. Together with the choice of appropriate dose constraints this would facilitate the setting of release criteria and patient restrictions., (© 2024. The Author(s).)

Purpose: To assess a large panel of MR compatible detectors on the full range of measurements required for a 0.35 T MR-linac commissioning by using a specific statistical method represented as a continuum of comparison with the Monte Carlo (MC) TPS calculations. This study also describes the commissioning tests and the secondary MC dose calculation validation., Material and Methods: Plans were created on the Viewray TPS to generate MC reference data. Absolute dose points, PDD, profiles and output factors were extracted and compared to measurements performed with ten different detectors: PTW 31010, 31021, 31022, Markus 34045 and Exradin A28 MR ionization chambers, SN Edge shielded diode, PTW 60019 microdiamond, PTW 60023 unshielded diode, EBT3 radiochromic films and LiF µcubes. Three commissioning steps consisted in comparison between calculated and measured dose: the beam model validation, the output calibration verification in four different phantoms and the commissioning tests recommended by the IAEA-TECDOC-1583., Main Results: The symmetry for the high resolution detectors was higher than the TPS data of about 1%. The angular responses of the PTW 60023 and the SN Edge were - 6.6 and - 11.9% compared to the PTW 31010 at 60°. The X/Y-left and the Y-right penumbras measured by the high resolution detectors were in good agreement with the TPS values except for the PTW 60023 for large field sizes. For the 0.84 × 0.83 cm 2 field size, the mean deviation to the TPS of the uncorrected OF was - 1.7 ± 1.6% against - 4.0 ± 0.6% for the corrected OF whereas we found - 4.8 ± 0.8% for passive dosimeters. The mean absolute dose deviations to the TPS in different phantoms were 0 ± 0.4%, - 1.2 ± 0.6% and 0.5 ± 1.1% for the PTW 31010, PTW 31021 and Exradin A28 MR respectively., Conclusions: The magnetic field effects on the measurements are considerably reduced at low magnetic field. The PTW 31010 ionization chamber can be used with confidence in different phantoms for commissioning and QA tests requiring absolute dose verifications. For relative measurements, the PTW 60019 presented the best agreement for the full range of field size. For the profile assessment, shielded diodes had a behaviour similar to the PTW 60019 and 60023 while the ionization chambers were the most suitable detectors for the symmetry. The output correction factors published by the IAEA TRS 483 seem to be applicable at low magnetic field pending the publication of new MR specific values., (© 2024. The Author(s).)