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Introduction Pterygium is an ocular surface disorder characterized by a hyperplastic growth of conjunctiva encroaching over the cornea. It causes redness, watering, and foreign body sensation. Surgical excision is the preferred mode of treatment when there is encroachment over the visual axis, chronic irritation, restricted ocular motility, and cosmetic concerns. Various surgical methods have been adopted for the treatment and to prevent recurrences. This study assessed the effectiveness and safety of 20% ethanol as an adjuvant in pterygium excision with conjunctival autograft implantation, evaluating surgical outcomes. Methods A prospective hospital-based interventional study was conducted among 30 patients with pterygium from August 2022 to December 2023. Patients were evaluated preoperatively for anterior segment, posterior segment, visual acuity, and corneal astigmatism. Pterygium was excised using 20% ethanol as an adjuvant, and conjunctival autograft was placed over the bare sclera without sutures. Patients were evaluated on postoperative days 1, 8, 30, and 90 for graft condition, visual acuity, corneal astigmatism, and associated complications. Results After three months of follow-up, the mean visual acuity improved to LogMAR 0.46±0.35 (p=0.001), which was statistically significant, and the average corneal astigmatism decreased from 3.36±2.87 to 0.87±0.57 (p=0.0001). No recurrence was noted among the participants. Conclusion This study has shown that using 20% ethanol as an adjuvant for pterygium excision facilitated clean dissection of a pterygium from the underlying cornea and the pterygium-induced corneal astigmatism has significantly decreased, which led to progress in vision.
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Numerous structural and conductive properties of barium cerate (BC) make this material a promising candidate for energy storage applications. In this work, we demonstrated that BC can be proficiently functionalized by incorporating trivalent samarium ions to give rise to optical properties. Single-phased BaCeO3:Sm3+ (BCS) phosphors were synthesized by gel combustion technique followed by calcination. The crystal structure, optical properties, and prospective applications in LEDs were investigated systematically. By linking the information acquired from the diffuse reflectance spectra with that of the PL spectra, we better understood the electronic level structure and energy transfer mechanism. Fine yellow-orange luminescence with 100% color purity (CP) and lower Correlated Color Temperature (CCT) has been achieved via energization at 348 nm wavelength. The x = 0.02 Sm3+ has been identified as the optimized content for the luminescence with a quantum efficiency of 34.2%. Obtained yellow-orange coordinates (0.564, 0.435) are proximate to commercialized L3 rank amber LED (Nichia corporation). The present results signify that UV light can suitably energize the BCS phosphor to get monochromatic amber light which can be used to guard medications during manufacture and storage.
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Stereotactic radiosurgery (SRS) is increasingly being used to manage solitary or multiple brain metastasis. This study aims to compare and validate Anisotropic Analytical Algorithm (AAA) and AcurosXB (AXB) algorithms of Eclipse Treatment Planning System (TPS) in RapidArc-based SRS plans of patients with solitary brain metastasis. Twenty patients with solitary brain metastasis who have been already treated with RapidArc SRS plans calculated using AAA plans were selected for this study. These plans were recalculated using AXB algorithm keeping the same arc orientations, multi-leaf collimator apertures, and monitor units. The two algorithms were compared for target coverage parameters, isodose volumes, plan quality metrics, dose to organs at risk and integral dose. The dose calculated by the TPS using AAA and AXB algorithms was validated against measured dose for all patient plans using an in-house developed cylindrical phantom. An Exradin A14SL ionization chamber was positioned at the center of this phantom to measure the in-field dose. NanoDot Optically Stimulated Luminescent Dosimeters (OSLDs) (Landauer Inc.) were placed at distances 3.0 cm, 4.0 cm, 5.0 cm, and 6.0 cm respectively from the center of the phantom to measure the non-target dose. In addition, the planar dose distribution was measured using amorphous silicon aS1000 Electronic Portal Imaging Device. The measured 2D dose distribution was compared against AAA and AXB estimated 2D distribution using gamma analysis. All results were tested for significance using the paired t-test at 5% level of significance. Significant differences between the AAA and AXB plans were found only for a few parameters analyzed in this study. In the experimental verification using cylindrical phantom, the difference between the AAA calculated dose and the measured dose was found to be highly significant (p < 0.001). However, the difference between the AXB calculated dose and the measured dose was not significant (pâ¯=â¯0.197). The difference between AAA/AXB calculated and measured at non-target locations was statistically insignificant at all four non-target locations and the dose calculated by both AAA and AXB algorithms shows a strong positive correlation with the measured dose. The results of the gamma analysis show that the AXB calculated planar dose is in better agreement with measurements compared to the AAA. Even though the results of the dosimetric comparison show that the differences are mostly not significant, the measurements show that there are differences between the two algorithms within the target volume. The AXB algorithm may be therefore more accurate in the dose calculation of VMAT plans for the treatment of small intracranial targets. For non-target locations either algorithm can be used for the estimation of dose accounting for their limitations in non-target dose estimations.