PURPOSE: To introduce the CT based three dimensional (3D) conformal brachytherapy treatment planning for interstitial implants, to compare the conventional X-ray film based planning with the 3D planning from the point of view of reconstruction and dosimetry, to discuss the differences and highlight the advantages. MATERIAL AND METHODS: On 10 patients with breast and 5 with head and neck tumor treated with HDR interstitial implants, following the catheter implantations, CT scans were taken at 5 mm spacing. The images were loaded into the PLATO BPS v14.0 3D planning system for brachytherapy. The contours of the target volume and critical structures were outlined on each slice, the catheter describing points were identified and the anatomical structures and catheter positions were reconstructed in 3D. Having taken into account the target volume, the active lengths were determined in each catheter, and dose optimization on dose points on target was performed. RESULTS: The 3D treatment planning was applied at interstitial breast treatments and head and neck implants. We investigated the dose distribution on axial, reconstructed coronal / sagittal planes and in 3D view with respect to anatomical structures. Dose volume histograms related to the target volume and critical structures were used for quantitative assessment of the plans. We found that the conformal dose distribution might result in increase of dose inhomogeneity within the target volume. CONCLUSIONS: The three dimensional brachytherapy treatment planning can be introduced into the clinical practice under proper technical conditions. A tradeoff between conformality and dose homogeneity results in an acceptable dose plan. The dose inhomogeneity can be decreased with the use of CT scans taken before the implantation. The guidelines and quantitative parameters describing the dose distribution, which can be used for determining the optimal dose distribution in clinical point of view, are still waiting to be established.
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Alzheimers Dement
December 2024
The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Australia, Melbourne, VIC, Australia.
Background: Iron is vital for metabolism but can act as a catalyst for oxidative damage. Elevated brain iron, determined from biomarkers of iron (CSF ferritin and quantitative susceptibility mapping MRI) and from post-mortem measurement of brain iron, has been associated with accelerated cognitive decline in multiple Alzheimer's disease (AD) clinical, cohorts. These findings supported the hypothesis that treatment with the brain-permeable iron chelator deferiprone may be associated clinical benefit in AD.
View Article and Find Full Text PDFBackground: Alzheimer's disease (AD) is characterized by progressive atrophy of the cerebral cortex and hippocampus, with concomitant increase in ventricular volume. Lomecel-B is a novel cell-based therapeutic approach to AD that targets neuroinflammation, microvascular dysfunction, and has the potential to stimulate endogenous tissue regeneration. We conducted MRI analysis of brain morphology in the CLEAR-MIND study, a 49-patient proof-of-concept study that tested 3 different dosing regimens of Lomecel-B vs placebo in patients with mild AD dementia.
View Article and Find Full Text PDFAlzheimers Dement
December 2024
Johns Hopkins University School of Medicine, Baltimore, MD, USA.
Background: Cognitive decline associated with Alzheimer's disease (AD) correlates with hyperphosphorylated tau (pTau) propagating between neurons along networks connected by synapses. It has been hypothesized this transcellular transmission occurs partially by extracellular vesicles (EVs). Both genetic and pharmacological inhibition of nSMase2 has been found to inhibit EV biogenesis and pTau propagation.
View Article and Find Full Text PDFAlzheimers Dement
December 2024
Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.
Background: Alzheimer's disease (AD) is a progressive and multifactorial neurodegenerative disease that still has no cure. Different pathological processes contribute to the disease's development, such as the presence of amyloid beta (Aβ) plaques, neurofibrillary tangles (NFTs), glutamatergic excitotoxicity, oxidative stress, and neuroinflammation. Chalcones are polyphenolic compounds of natural origin with a wide range of biological activities, and emerging studies have reported neurotrophic activity, anti-inflammatory and antioxidant effects, and the inhibition of Aβ aggregation.
View Article and Find Full Text PDFObjectives: To evaluate the otolaryngology surgical capacity in Harare, Zimbabwe by analyzing procedural volumes across four hospitals, one private and three public, from 2019 to 2022.
Methods: A retrospective review of hand-written surgical case logs was conducted at Harare Eye, Ear, Nose, and Throat Institute (HEENT), Parirenyatwa Group of Hospitals (PGH), Sally Mugabe Children's Hospital (SMCH), and Sally Mugabe Adult's Hospital (SMAH). Patient age and surgical intervention for all otolaryngology surgeries performed in the operating room from 2019 to 2022 were recorded.
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