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Auteur Jagadesh C. Reddy
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Ajouter le résultat dans votre panier Affiner la rechercheDifferences in Image Quality after Three Laser Keratorefractive Procedures for Myopia / Samrat Sarkar in OVS : Optometry & Vision Science, vol. 99, 02 (février 2022)
[article]
in OVS : Optometry & Vision Science > vol. 99, 02 (février 2022)
Titre : Differences in Image Quality after Three Laser Keratorefractive Procedures for Myopia Type de document : article de périodique Auteurs : Samrat Sarkar ; Preetirupa Devi ; Pravin K. Vaddavalli ; Jagadesh C. Reddy ; Shrikant Bharadwaj Année de publication : 2022 Langues : Français (fre) Descripteurs (mots clés) : [Thésaurus Mesh]:M:Myopie:Myopie / chirurgie
[Thésaurus Mesh]Collecte de données
[Thésaurus Mesh]Procédures de chirurgie réfractiveRésumé : SIGNIFICANCE
Psychophysical estimates of spatial and depth vision have been shown to be better after bilateral ReLEx small-incision lenticule extraction (SMILE) refractive surgery for myopia, relative to photorefractive keratectomy (PRK) and femtosecond laser-assisted in situ keratomileusis (FS-LASIK). The present study provides the optical basis for these findings using computational image quality analysis.
PURPOSE
This study aimed to compare longitudinal changes in higher-order wavefront aberrations and image quality before and after bilateral PRK, FS-LASIK, and SMILE refractive procedures for correcting myopia.
METHODS
Wavefront aberrations and image quality of both the eyes of 106 subjects (n = 40 for FS-LASIK and SMILE and n = 26 for PRK) were determined pre-operatively and at 1-week, 1-month, 3-month, and 6-month post-operative intervals using computational through-focus analysis for a 6-mm pupil diameter. Image quality was quantified in terms of its peak value and its interocular difference, residual defocus that was needed to achieve peak image quality (best focus), and the depth of focus.
RESULTS
The increase in root mean squared deviations of higher-order aberrations post-operatively was lesser after SMILE (1-month visit median [25th to 75th interquartile range], 0.34 μm (0.28 to 0.39 μm]) than after PRK (0.80 μm [0.74 to 0.87 μm]) and FS-LASIK (0.74 μm [0.59 to 0.83 μm]; P ≤ .001), all relative to pre-operative values (0.20 μm [0.15 to 0.30 μm]). The peak image quality dropped and its interocular difference increased, best focus shifted myopically by 0.5 to 0.75 D, and depth of focus widened significantly after PRK and FS-LASIK surgeries, all relative to pre-operative values (P < .001). All these changes were negligible but statistically significant in a minority of instances after SMILE surgery (P ≥ .01).
CONCLUSIONS
Although all three refractive surgeries correct myopia, the image quality and its similarity between eyes are better and closer to pre-operative values after SMILE, compared with FS-LASIK and PRK. These results can be explained from the underlying increase in higher-order wavefront aberrations experienced by the eye post-operatively.Permalink : https://bibliotheque.helb-prigogine.be/opac_css/index.php?lvl=notice_display&id= [article]Exemplaires
Cote Support Localisation Section Disponibilité aucun exemplaire Interocular Contrast Balancing Partially Improves Stereoacuity in Keratoconus / Bhagya Lakshmi Marella in OVS : Optometry & Vision Science, vol. 100, 04 (Avril 2023)
[article]
in OVS : Optometry & Vision Science > vol. 100, 04 (Avril 2023)
Titre : Interocular Contrast Balancing Partially Improves Stereoacuity in Keratoconus Type de document : article de périodique Auteurs : Bhagya Lakshmi Marella ; Pravin K. Vaddavalli ; Jagadesh C. Reddy ; Miriam L. Conway ; Catherine M. Suttle ; Shrikant Bharadwaj Année de publication : 2023 Langues : Français (fre) Descripteurs (mots clés) : [Thésaurus Mesh]Kératocône
[Thésaurus Mesh]Sensibilité au contrasteMots-clés : stéréoacuité équilibrage du contraste contraste interoculaire Résumé : SIGNIFICANCE: Partial improvement in stereoacuity may be achieved by balancing the contrast input to the two eyes of patients with bilaterally asymmetric keratoconus. PURPOSE: Interocular differences in image quality, characterized by dissimilar contrast loss and phase shifts, are implicated in stereoacuity loss in keratoconus. This study determined whether contrast balancing improves stereoacuity in this disease condition and, if so, whether it is dependent on the baseline interocular contrast imbalance. METHODS: Interocular contrast imbalance and stereoacuity of 43 subjects (16 to 33 years) with bilaterally asymmetric keratoconus were tested with spectacle correction as baseline using a binocular rivalry paradigm and random-dot stereograms, respectively. Stereoacuity measurements were repeated in a subset of 33 subjects at their contrast balance point (i.e., contrast level in stronger eye allowing balanced rivalry with 100% contrast in weaker eye) and with contrast levels biased in favor of stronger or weaker eye, all conditions in randomized order. RESULTS: Contrast imbalance level was significantly correlated with the subject's stereoacuity at baseline (r = −0.47, P = .002). The median (25th to 75th interquartile range) stereoacuity improved by 34.6% (19.0 to 65.1%) from baseline (748.8 arc sec [261.3 to 1257.3 arc sec]) to the contrast balanced condition (419.0 arc sec [86.6 to 868.9 arc sec]) (P < .001), independent of their baseline stereoacuity or contrast imbalance levels (r < 0.2, P > .26 for both). Contrast bias in favor of the weaker eye (881.3 arc sec [239.6 to 1707.6 arc sec]) worsened stereoacuity more than a bias toward the stronger eye (502.6 arc sec [181.9 to 1161.4 arc sec]), both relative to the contrast balanced condition (P < .002). CONCLUSIONS: Interocular contrast balancing partially improves stereoacuity in bilaterally asymmetric keratoconus, independent of their baseline contrast imbalance level. Cyclopean viewing may be inherently biased toward the input from the stronger eye in keratoconus. Note de contenu :
Permalink : https://bibliotheque.helb-prigogine.be/opac_css/index.php?lvl=notice_display&id= [article]Exemplaires
Cote Support Localisation Section Disponibilité aucun exemplaire Longitudinal Changes in Optical Quality, Spatial Vision, and Depth Vision after Laser Refractive Surgery for Myopia / Samrat Sarkar in OVS : Optometry & Vision Science, vol. 97, 05 (Mai 2020)
[article]
in OVS : Optometry & Vision Science > vol. 97, 05 (Mai 2020) . - p. 360-369
Titre : Longitudinal Changes in Optical Quality, Spatial Vision, and Depth Vision after Laser Refractive Surgery for Myopia Type de document : article de périodique Auteurs : Samrat Sarkar ; Shrikant Bharadwaj ; Jagadesh C. Reddy ; Pravin K. Vaddavalli Année de publication : 2020 Article en page(s) : p. 360-369 Langues : Français (fre) Descripteurs (mots clés) : [Thésaurus Mesh]:M:Myopie:Myopie / chirurgie
[Thésaurus Mesh]:M:Myopie:Myopie / thérapie
[Thésaurus Mesh]Chirurgie de la cornée par laser
[Thésaurus Mesh]Myopie
[Thésaurus Mesh]Procédures de chirurgie réfractive
[Thésaurus Mesh]Vision binoculaire
[Thésaurus HELB]:Optique:vision spatialeMots-clés : corneal surgery, laser myopia surgery refractive surgical procedures vision, binocular Résumé : SIGNIFICANCE: Laser refractive surgery procedures are efficacious at correcting myopia, but they result in longterm deterioration of optical quality that affects monocular and binocular visual performance. The study shows that the optical quality of the two eyes needs to be similar to optimize binocular visual performance after surgery. PURPOSE: This study aimed to systematically analyze longitudinal changes in optical quality, high- and lowcontrast logMAR acuity and random-dot stereoacuity before and after three refractive surgery procedures for correcting myopia. METHODS: A total of 106 subjects (laser-assisted in situ keratomileusis, 40; photorefractive keratectomy, 26; small-incision lenticule extraction, 40) with myopia and astigmatism ≤1.5 D participated in this prospective cohort-based study. All aforementioned outcome variables were measured in both eyes pre-operatively and 1 week and 1, 3, and 6 months post-operatively. RESULTS: Pre-operative myopic spherical equivalent of refraction (median [25th to 75th interquartile range], −6.4 D [−8.0 to −4.2 D] for laser-assisted in situ keratomileusis, −4.3 D [−5.0 to −3.5 D] for photorefractive keratectomy, −5.5 D [−6.5 to −4.3 D] for small-incision lenticule extraction) was corrected to within ±0.75 D of emmetropia in all cohorts up to 6 months post-operatively (P < .001). Higher-order wavefront aberrations, uncorrected high- and low-contrast logMAR acuity, and stereoacuity all worsened and remained so up to 6 months postoperatively, relative to pre-operative values (P < .001). Stereoacuity worsened with both interocular average and difference in the magnitude of higher-order aberrations, whereas logMAR acuities worsened only with interocular average of these aberrations (r 2 ≥ 0.40; P < .01 for all). CONCLUSIONS: Although the refractive surgery procedures tested here correct myopia, they result in a sustained (up to 6 months) loss of optical quality and spatial and depth-related visual functions post-operatively. Both interocular average and difference in the eye's optical quality seem to impair binocular visual functions after refractive surgery for myopia. Note de contenu :
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Cote Support Localisation Section Disponibilité aucun exemplaire