Association between patent ductus arteriosus flow and home oxygen therapy in extremely preterm infants.

BACKGROUND: Central blood flow measurements include the estimation of right and left ventricular output (RVO, LVO), superior vena cava (SVC) flow, and calculated patent ductus arteriosus (PDA) flow. We aimed to provide an overview of the maturation patterns of these values and the relationship between PDA flow and the need for home oxygen therapy. METHODS: This prospective single-center study was conducted in infants born at <26 weeks of gestation. We performed echocardiographic measurements five times during their life (from the 4th post-natal day to the 36th postmenstrual week). RESULTS: Sixty patients with a mean birth weight of 680 (590, 760) g were included. Postnatal development of LVO and PDA flow peaked at the end of the second postnatal week (427 and 66 mL/kg/min, respectively). The RVO increased between days 4 and 7-8. The SVCF was most stable. The development curves of PDA flow differed between the groups with (n = 28; 47%) and without home oxygen therapy. CONCLUSION: We present the central blood flow values and their postnatal development in infants <26 weeks of gestation. This study demonstrates the association between PDA flow and the future need for home oxygen therapy. IMPACT: This study enriches our knowledge of the long-term development of central blood flow parameters and derived patent ductus arteriosus (PDA) flow in extremely preterm infants (<26 weeks). While pulmonary resistance decreased, PDA flow continued to increase from day 4 to the end of the second week of life. Similarly, left ventricular output increased as a marker of preload. The superior vena cava flow remained stable. The observed association between PDA flow and an unfavorable respiratory outcome is important for future studies focusing on the prevention of chronic lung disease.

An Investigation of Efficiency Issues in a Low-Pressure Steam Turbine Using Neural Modelling.

This study utilizes neural networks to detect and locate thermal anomalies in low-pressure steam turbines, some of which experienced a drop in efficiency. Standard approaches relying on expert knowledge or statistical methods struggled to identify the anomalous steam line due to difficulty in capturing nonlinear and weak relations in the presence of linear and strong ones. In this research, some inputs that linearly relate to outputs have been intentionally neglected. The remaining inputs have been used to train shallow feedforward or long short-term memory neural networks using measured data. The resulting models have been analyzed by Shapley additive explanations, which can determine the impact of individual inputs or model features on outputs. This analysis identified unexpected relations between lines that should not be connected. Subsequently, during periodic plant shutdown, a leak was discovered in the indicated line.

Posterior chamber phakic intraocular lens for the correction of presbyopia in highly myopic patients.

PURPOSE: To report the initial experience with a new presbyopic phakic intraocular lens (pIOL) in the correction of high myopia and presbyopia. SETTING: Gemini Eye Clinic, Zlin, Czech Republic. DESIGN: Prospective cohort study. METHODS: Presbyopic eyes with moderate to high myopia were implanted with a presbyopic posterior chamber pIOL (IPCL). The visual acuities at near and distance, endothelial cell density, and ocular condition were examined 1 week, 3 months, 1 year and 2 years postoperatively. RESULTS: The mean uncorrected distance visual acuity improved significantly from 1.25 logarithm of the minimum angle of resolution (logMAR) (1.15 to 1.35 95% confidence interval [CI]) to 0.11 logMAR (95% CI, 0.03 to 0.17) (P < .0001). No eye lost 1 or more lines of corrected distance visual acuity. The mean distance refraction improved significantly from -6.9 diopters (D) (range -8.6 to -5.3 D) preoperatively to -0.35 D (range -0.55 to -0.15 D, P < .0001) with less than -0.5 D residual refraction in 11 of 17 eyes. Fifteen of 17 eyes had improved uncorrected near visual acuity to J1 (Jaeger chart) at the 2-year follow-up. The near addition at the 2-year follow-up decreased from preoperatively +1.26 D (range 0.19 to 2.34 D) to +0.39 D (range 0.18 to 0.60 D). The mean endothelial cell density was reduced from 2552 cells/mm (range 2421 to 2682 cells/mm) to 2299 cells/mm (range 2108 to 2490 cells/mm) after 2 years. All patients were subjectively satisfied with the outcomes. CONCLUSIONS: The new pIOL provided good visual outcomes in near and far distances in an initial case series of patients.

Photorefractive intrastromal crosslinking for correction of hyperopia: 12-month results.

PURPOSE: To evaluate the efficacy of epithelium-on photorefractive intrastromal crosslinking (PiXL), a noninvasive procedure to reduce refractive error in patients with low hyperopia. SETTING: Gemini Eye Clinic, Zlin, Czech Republic. DESIGN: Prospective single-center study. METHODS: Twenty-two low hyperopic eyes were enrolled and underwent PiXL treatment according to a standardized treatment protocol. Visual acuity, subjective distance refraction, keratometry, topography, pachymetry, subjective discomfort, and endothelial cell density (ECD) were recorded during 12-month follow-up. RESULTS: In 22 eyes, the median manifest refraction decreased significantly (P < .0001) from +0.75 diopters (D) (interquartile range [IQR], +0.63 to +1.06 D), median and IQR) diopters (D) preoperatively to +0.25 D (IQR, 0.0 to +0.50 D) at 12-month follow-up and remained stable. Seventy-seven percent of eyes achieved refraction within ± 0.50 D of emmetropia by 1 month postoperatively and was stable through 12-month follow-up. ECD was stable and did not show significant changes. There was low incidence of postoperative pain and dry eye. CONCLUSIONS: PiXL is a promising alternative to conventional laser refractive surgeries for low hyperopia. Further studies are warranted to optimize treatment parameters for a wider range of refractive errors and to evaluate the potential to improve precision.