Improvement of patient localization repeatability using a light-section based optical surface guidance system in a pre-positioning procedure

PurposeSurface-guided radiotherapy is useful for the pre-positioning and monitoring of radiotherapy. The purpose of this study was to investigate the impact of surface guidance on the repeatability of patient localization and to estimate the specific point at which high positional errors occur.Materials and methodsTen patients without the VOXELAN system (non-VXLN group) and 10 patients with the VOXELAN as the pre-positioning procedure (VXLN group) were included in this analysis. Twelve regions of interest (ROI) were defined in all the patients to verify any misalignment during radiotherapy. Thirteen ROIs were defined on the isocenter.ResultsCompared with the non-VXLN group, the translational positional errors of the VXLN group were the same for all the ROIs. The mean translational positional errors of the VXLN group in the longitudinal direction were approximately 0.1 mm, and the standard deviation was the largest among the three directions in all the ROIs. The magnitude of the standard deviation in the non-VXLN group varied independently of the ROI and direction. The standard deviations of the VXLN group in the longitudinal direction were large in all the ROIs, while the standard deviations in the vertical and lateral directions were small.ConclusionPre-positioning with a surface guidance system reduced the body twist and rotation, which could not be corrected by image-guided radiotherapy alone. Since the VOXELAN can detect positioning errors quickly and without additional radiation exposure to the patient, it can be used as a tool for pre-positioning in radiotherapy.     

Co-precipitates of lumefantrine-Eudragit E PO for dissolution improvement

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Miocardio no compactado: ¿una enfermedad o un rasgo fenotípico?

Left ventricular noncompaction is a poorly defined and controversial entity, with wide phenotypic expression: from a simple anatomical trait to a disease with overt cardiac affection. Current diagnostic criteria rely exclusively on morphologic features of hypertrabeculation, which have low specificity for identifying true cardiomyopathy cases. The management of left ventricular noncompaction is also heterogeneous, and there are no dedicated clinical practice guidelines. The most common cardiovascular complications are heart failure, ventricular arrhythmias, and systemic embolisms. In this review, we discuss the diagnostic limitations of the available criteria, and propose a comprehensive alternative approach (including functional imaging variables, tissue characterization, genetics, and family screening) that may help in the differential diagnosis of hypertrabeculation cases. We also describe the genetic background of the disease and discuss the overlap with other cardiomyopathies. Finally, we focus on controversial issues in clinical management and suggest the use of the previously-mentioned variables for risk stratification and for individualization of patient follow-up.     

Registro español de marcapasos. XIX informe oficial de la Asociación del Ritmo Cardiaco de la Sociedad Española de Cardiología (2021)

Introduction and objectivesThis document includes cardiac pacing activity performed in Spain in 2021: figures for implanted devices, demographic and clinical factors, characteristics of the implanted material, and remote monitoring data.MethodsThe European Pacemaker Patient Card, the CardioDispositivos.es online platform, the centers’ own databases and the data provided by the supplier companies are used as sources of information.Results17.360 procedures were registered from 95 hospitals, which represents 43% of the activity. The implantation rates of conventional and resynchronization pacemakers were 822 and 31 units per million population, respectively. 652 leadless pacemakers were implanted. The mean age of implantation is high (78.8 years), and atrioventricular block is the most frequent electrocardiographic abnormality. Dual-chamber pacing mode predominated, nonetheless single-chamber pacing was performed in 19% of patients in sinus rhythm, mainly in the elderly. 28.5% of implanted conventional pacemakers and 56,2% of low-energy resynchronization pacemakers were included in the remote monitoring program.ConclusionsIn 2021 the number of conventional pacemakers increased by 8.3% and resynchronizers by 18.9%, despite the decrease in low-energy resynchronization, probably attributable to the development of physiological pacing. Leadless pacemakers increased by 25%. The expansion of remote monitoring continued, consolidating as a fundamental follow-up method.