Barryleonard4291
The purpose of this study was to assess the feasibility of dual-energy CT-based material decomposition using dual-X-ray spectra information to determine local concentrations of holmium microspheres in phantoms and in an animal model.
A spectral calibration phantom with a solution containing 10 mg/mL holmium and various tube settings was scanned using a third-generation dual-energy CT scanner to depict an energy-dependent and material-dependent enhancement vectors. A serial dilution of holmium (microspheres) was quantified by spectral material decomposition and compared with known holmium concentrations. Subsequently, the feasibility of the spectral material decomposition was demonstrated in situ in three euthanized rabbits with injected (radioactive) holmium microspheres.
The measured CT values of the holmium solutions scale linearly to all measured concentrations and tube settings (R
= 1.00). Material decomposition based on CT acquisitions using the tube voltage combinations of 80/150 Sn kV or 100/150 Sn kV allow the most accurate quantifications for concentrations down to 0.125 mg/mL holmium.
Dual-energy CT facilitates image-based material decomposition to detect and quantify holmium microspheres in phantoms and rabbits.
• Quantification of holmium concentrations based on dual-energy CT is obtained with good accuracy. • The optimal tube-voltage pairs for quantifying holmium were 80/150 Sn kV and 100/150 Sn kV using a third-generation dual-source CT system. • Quantification of accumulated holmium facilitates the assessment of local dosimetry for radiation therapies.
• Quantification of holmium concentrations based on dual-energy CT is obtained with good accuracy. • The optimal tube-voltage pairs for quantifying holmium were 80/150 Sn kV and 100/150 Sn kV using a third-generation dual-source CT system. • Quantification of accumulated holmium facilitates the assessment of local dosimetry for radiation therapies.
Toric intraocular lenses (IOL) provide areliable and predictable option for permanent correction of corneal astigmatism. In order to determine the lens strength necessary for achieving the desired correction, the operator can either use the calculation mode implemented in the biometry device or the calculation service offered by the lens manufacturer; however, in many cases a classical lens calculation from biometric data is not carried out but only a simplified estimation, which translates the corneal astigmatism into the torus of the toric IOL. This translational ratio, which is mostly used as an average standard value, can however show a substantial range of variation, so that in a worst case scenario an undercorrection of the refractive cylinder of up to 12.5 % or an overcorrection of up to 17 % can result. The purpose of this study was to elaborate the biometric effect sizes which determine the relationship between the corneal astigmatism to be corrected and the torus necessary for a full correction oftrices or full aperture ray tracing) is recommended.Punctate inner choroidopathy (PIC) is often accompanied by the development of choroidal neovascularization (CNV). The identification of a fresh CNV in the context of PIC is often difficult. We present the case of a 30-year-old female patient with typical morphological features of PIC. A CNV could not be detected with certainty by optical coherence tomography (OCT) or by fluorescein angiography (FAG); however, OCT angiography (OCT-A) revealed a circumscribed CNV. The case suggests that there are a high number of undiagnosed, subclinical secondary CNVs not requiring treatment in PIC patients.
Subretinal hemorrhage involving the macula is atypical complication in avariety of retinal diseases, whereby age-related macular degeneration (AMD) is by far the leading cause.
A literature search was carried out in PubMed.
Numerous studies have demonstrated the effectiveness of various approaches to the management of submacular hemorrhage, including intravitreal anti-VEGF treatment, pneumatic displacement supported by fibrinolytic agents or surgical drainage.
There is currently no consensus regarding evidence-based standard treatment for macular hemorrhage, although there is atrend towards minimally invasive approaches. Regardlessofthe choice of the primary treatment approach, the time to treatment and an accompanying intravitreal treatment with VEGF inhibitors are decisive for the functional outcome.
There is currently no consensus regarding evidence-based standard treatment for macular hemorrhage, although there is a trend towards minimally invasive approaches. Regardless of the choice of the primary treatment approach, the time to treatment and an accompanying intravitreal treatment with VEGF inhibitors are decisive for the functional outcome.The original article can be found online.
Decline in mitochondrial function occurs with aging and may increase mortality. We discuss mitochondrial contribution to Covid-19 sepsis, specifically the complex interaction of innate immune function, viral replication, hyper-inflammatory state, and HIF-α/Sirtuin pathways.
Articles from PubMed/Medline searches were reviewed using the combination of terms "SARS-CoV-2, Covid-19, sepsis, mitochondria, aging, and immunometabolism".
Evidence indicates that mitochondria in senescent cells may be dysfunctional and unable to keep up with hypermetabolic demands associated with Covid-19 sepsis. Mitochondrial proteins may serve as damage-associated molecular pattern (DAMP) activating innate immunity. Disruption in normal oxidative phosphorylation pathways contributes to elevated ROS which activates sepsis cascade through HIF-α/Sirtuin pathway. Viral-mitochondrial interaction may be necessary for replication and increased viral load. Hypoxia and hyper-inflammatory state contribute to increased mortality associated with Covid-19 sepsis.
Aging is associated with worse outcomes in sepsis. Modulating Sirtuin activity is emerging as therapeutic agent in sepsis. HIF-α, levels of mitochondrial DNA, and other mitochondrial DAMP molecules may also serve as useful biomarker and need to be investigated. Epigenetic inhibitor These mechanisms should be explored specifically for Covid-19-related sepsis. Understanding newly discovered regulatory mechanisms may lead to the development of novel diagnostic and therapeutic targets.
Aging is associated with worse outcomes in sepsis. Modulating Sirtuin activity is emerging as therapeutic agent in sepsis. HIF-α, levels of mitochondrial DNA, and other mitochondrial DAMP molecules may also serve as useful biomarker and need to be investigated. These mechanisms should be explored specifically for Covid-19-related sepsis. Understanding newly discovered regulatory mechanisms may lead to the development of novel diagnostic and therapeutic targets.