Purpose: To compare the spatial resolution threshold in the central visual field of pseudophakic patients with monofocal and multifocal intraocular lenses (IOLs).
Setting: Eye Clinic, University of Trieste, Italy.
Methods: Twenty phakic normal subjects and four groups of 20 pseudophakic patients each, implanted with refractive and diffractive multifocal IOLs (Domilens Progress 1, AMO Array MPC25NB, or Pharmacia 811X) or with monofocal IOLs (Allergan PC43NB), were studied. The spatial resolution threshold in the central visual field was assessed using high-pass resolution perimetry. Measurements were performed adding spherical correction to test the different foci of the IOL.
Results: No significant differences between phakic subjects and pseudophakic patients with monofocal IOLs were found. In distance vision, no significant differences between patients with refractive multifocal IOLs and those with monofocal IOLs were found. The group with the diffractive multifocal IOL showed a significantly higher spatial resolution threshold (P = .003). In intermediate vision, the AMO Array group showed a significantly lower spatial resolution threshold than the other groups (P < .01). The best performance at near distance was in the diffractive group, which was statistically significantly different from the other groups (P < .001).
Conclusion: In the diffractive group, the high spatial resolution threshold in distance vision could be explained by the lower brightness of the principal focus, related to a different light energy division between the foci. In the Domilens group, the high spatial resolution threshold in near vision could be related to the light energy scattered in a large number of foci.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/s0886-3350(98)80206-x | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Ultra high density imaging arrays in diffuse optical tomography for human brain mapping improve image quality and decoding performance.
Sci Rep
January 2025
Mallinckrodt Institute of Radiology, Washington University School of Medicine, 4515 McKinley Ave., St. Louis, MO, 63110, USA.
Functional magnetic resonance imaging (fMRI) has dramatically advanced non-invasive human brain mapping and decoding. Functional near-infrared spectroscopy (fNIRS) and high-density diffuse optical tomography (HD-DOT) non-invasively measure blood oxygen fluctuations related to brain activity, like fMRI, at the brain surface, using more-lightweight equipment that circumvents ergonomic and logistical limitations of fMRI. HD-DOT grids have smaller inter-optode spacing (~ 13 mm) than sparse fNIRS (~ 30 mm) and therefore provide higher image quality, with spatial resolution ~ 1/2 that of fMRI, when using the several source-detector distances (13-40 mm) afforded by the HD-DOT grid.
View Article and Find Full Text PDFGRAiCE: reconstructing terrestrial water storage anomalies with recurrent neural networks.
Sci Data
January 2025
Department of Earth and Environmental Engineering, Columbia University, New York, USA.
The Gravity Recovery and Climate Experiment (GRACE) and its follow-on (GRACE-FO) missions have provided estimates of Terrestrial Water Storage Anomalies (TWSA) since 2002, enabling the monitoring of global hydrological changes. However, temporal gaps within these datasets and the lack of TWSA observations prior to 2002 limit our understanding of long-term freshwater variability. In this study, we develop GRAiCE, a set of four global monthly TWSA reconstructions from 1984 to 2021 at 0.
View Article and Find Full Text PDFPatial-frequency aware zero-centric residual unfolding network for MRI reconstruction.
Magn Reson Imaging
January 2025
Department of Medical Imaging, Pingyin people's Hospital, Jinan 250400, China.
Magnetic Resonance Imaging is a cornerstone of medical diagnostics, providing high-quality soft tissue contrast through non-invasive methods. However, MRI technology faces critical limitations in imaging speed and resolution. Prolonged scan times not only increase patient discomfort but also contribute to motion artifacts, further compromising image quality.
View Article and Find Full Text PDFA comparison of energy dispersive spectroscopy in transmission scanning electron microscopy with scanning transmission electron microscopy.
Ultramicroscopy
January 2025
Mechanical Engineering, University of Michigan, USA.
The objective of this work was to explore the capabilities of a field emission gun scanning electron microscope (FEG-SEM) equipped with a transmission scanning electron detector (TSEM) and energy dispersive spectroscopy (EDS) to identify nanoscale chemical heterogeneities in a gas atomization reaction synthesis (GARS) steel sample. The results of this analysis were compared to the same study conducted with scanning transmission electron microscopy (STEM) with EDS mapping. TSEM-EDS was performed using the standard spectral analysis approach, i.
View Article and Find Full Text PDFProjecting future snow changes at kilometer scale for adaptation using machine learning and a CMIP6 multi-model ensemble.
Sci Total Environ
January 2025
Universidad de Santiago de Chile, Santiago, Chile.
Assessing future snow cover changes is challenging because the high spatial resolution required is typically unavailable from climate models. This study, therefore, proposes an alternative approach to estimating snow changes by developing a super-spatial-resolution downscaling model of snow depth (SD) for Japan using a convolutional neural network (CNN)-based method, and by downscaling an ensemble of models from the Coupled Model Intercomparison Project Phase 6 (CMIP6) dataset. After assessing the coherence of the observed reference SD dataset with independent observations, we leveraged it to train the CNN downscaling model; following its evaluation, we applied the trained model to CMIP6 climate simulations.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!