Background And Purpose: A method for analytically solving the optimization of beam weighting in radiotherapy treatments using beam segmentation is presented.
Patients And Methods: A technique has been elaborated permitting the optimization of a flexible objective function which is defined by considering 'importance factors' for each anatomical region and 'allowed deviations' from the prescribed dose. As any change in these importance factors may lead to very different solutions, a statistical tool has been developed which varies the objective function automatically and iteratively to get the best possible results compatible with the chosen class solution. In addition, the spatial symmetry found in many anatomical sites is taken advantage of. Furthermore, freeware code has been written to run this optimization approach. The guidelines to design the beam segmentation used in our institution using organ avoidance criteria, and hence the suitable class solution for different anatomical sites, are given. A treatment-planning study for three anatomical sites is presented and, for two of them, the results obtained with both the suggested and the classical inverse approach are presented.
Results: The work presented might be used for beam weighting optimization in any radiotherapy treatment and furthermore, the suggested procedure may successfully confront the intensity-modulated radiation therapy (IMRT) problem and the obtained dose distributions fit the clinical constraints for all anatomical sites studied. When comparing with the classical inverse approach, both results are comparable in terms of dose distribution, but the suggested technique reduces the integral dose as the total number of monitor units is lower.
Conclusions: The developed code performs the optimization with a very low time cost and in addition, this process can be carried out with a conventional treatment-planning system with no need of dedicated IMRT software.
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http://dx.doi.org/10.1016/j.radonc.2003.10.008 | DOI Listing |
Int J Gynaecol Obstet
January 2025
Lis Hospital for Women's Health, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.
Objective: The rising rates of cesarean delivery (CD), which are a leading cause of intra-abdominal adhesions, represent a major concern for maternal health. We aimed to describe early maternal complications following CD in women with severe intra-abdominal adhesions.
Methods: A prospective observational study was conducted at a university-affiliated tertiary medical center (January 2021 and March 2023) in Israel.
Breast Cancer Res
January 2025
Precision Medicine, School of Clinical Sciences at Monash Health, Monash University, 246 Clayton Road, Clayton, VIC, 3168, Australia.
Background: Tumour DNA methylation has been investigated as a potential marker for breast cancer survival, but findings often lack replication across studies.
Methods: This study sought to replicate previously reported associations for individual CpG sites and multi-CpG signatures using an Australian sample of 425 women with breast cancer from the Melbourne Collaborative Cohort Study (MCCS). Candidate methylation sites (N = 22) and signatures (N = 3) potentially associated with breast cancer survival were identified from five prior studies that used The Cancer Genome Atlas (TCGA) methylation dataset, which shares key characteristics with the MCCS: comparable sample size, tissue type (formalin-fixed paraffin-embedded; FFPE), technology (Illumina HumanMethylation450 array), and participant characteristics (age, ancestry, and disease subtype and severity).
Cureus
December 2024
Ophthalmology, All India Institute of Medical Sciences, Madurai, Madurai, IND.
Melanoma is a highly aggressive malignancy originating from melanocytes, characterized by its potential to arise in various anatomic locations, both common and rare. The incidence of melanoma has been steadily increasing globally, with variations in clinical presentation, tumor behavior, and prognosis depending on the anatomical site involved. Understanding the diverse pathological spectrum of melanoma is critical for optimizing diagnostic and therapeutic strategies.
View Article and Find Full Text PDFEur J Paediatr Dent
January 2025
Dentistry Unit, AORN Santobono-Pausilipon Pediatric Hospital, 80129 Naples, Italy.
Aim: Self-inflicted oral-dental mutilations (SIODMs) are the result of an intentional or unintentional action that leads to anatomical and functional damage to the soft and hard tissues of the oral cavity. In paediatric patients they can be associated with both organic and functional diseases. A systematic review was conducted aiming to consolidate and integrate the existing knowledge on SIODM in paediatric patients.
View Article and Find Full Text PDFInt Med Case Rep J
January 2025
Department of Dermatology and Venereology, Faculty of Medicine, Universitas Padjadjaran - Dr. Hasan Sadikin Hospital, Bandung, West Java, Indonesia.
Verruca vulgaris is a cutaneous infection predominantly caused by human papillomavirus (HPV) type 1, 2, and 4. In immunocompromised individuals infected with human immunodeficiency virus (HIV) infection, HPV leads to a higher prevalence of infections and also has a greater likelihood of being infected with atypical types such as genital-associated HPV in extragenital sites. This case report describes a 48-year-old male patient who presented with skin-colored verrucous papules on the hands and feet, with no evidence of genital lesions.
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