scholarly journals Wavefront coherence area for predicting visual acuity of post-PRK and post-PARK refractive surgery patients

Author(s):  
Daniel D. Garcia ◽  
Corina van de Pol ◽  
Brian A. Barsky ◽  
Stanley A. Klein
2016 ◽  
Vol 27 (3) ◽  
pp. 308-311 ◽  
Author(s):  
Michael Mimouni ◽  
Achia Nemet ◽  
Russell Pokroy ◽  
Tzahi Sela ◽  
Gur Munzer ◽  
...  

Purpose To evaluate the effect of astigmatism axis on uncorrected distance visual acuity (UDVA) in emmetropic eyes that underwent laser refractive surgery. Methods This retrospective study included patients who underwent laser in situ keratomileusis or photorefractive keratectomy between January 2000 and December 2015 at the Care-Vision Laser Centers, Tel Aviv, Israel. Eyes with a 3-month postoperative spherical equivalent between -0.5 D and 0.5 D were included in this study. Eyes with ocular comorbidities and planned ametropia were excluded. Study eyes were divided into 3 groups according to the steep astigmatic axis: with the rule (WTR) (60-120), oblique (31-59 or 121-149), and against the rule (ATR) (0-30 or 150-180). The UDVA of these 3 groups was compared. The oblique group was divided into oblique ATR and oblique WTR, which were compared with each other. Results A total of 17,416 consecutive eyes of 8,708 patients were studied. The WTR eyes (n = 10,651) had significantly better UDVA (logMAR 0.01 ± 0.08) than the oblique (n = 3,141, logMAR 0.02 ± 0.09) and ATR eyes (n = 3,624, logMAR 0.02 ± 0.10) (p<0.001). The oblique WTR group had significantly better UDVA than the oblique ATR group (p<0.001). The UDVA of the oblique and ATR groups was similar. Stepwise multiple regression analysis showed that the group accounted for 15% of the UDVA variance (p = 0.04). Conclusions The astigmatic axis has a small but significant effect on UDVA in emmetropic eyes; WTR was better than oblique and ATR astigmatism. Therefore, when correcting astigmatism, it may be preferable to err towards WTR astigmatism.


2021 ◽  
Vol 14 (3) ◽  
pp. 102-105
Author(s):  
N. V. Khodzhabekyan ◽  
A. T. Khandzhyan ◽  
A. V. Ivanova ◽  
K. B. Letnikova ◽  
A. S. Sklyarova

Purpose: to evaluate the prospects of customized Finalfit based ablation for optical rehabilitation of a patient with corneal surface errors caused by intrasurgical microtome-induced damage of a corneal flap during a LASIK excimer laser correction of vision.Material and methods. In Helmholtz Center, a patient with such damage was given a phototherapeutic keratectomy (PTK) combined with topographyguided photorefractive keratectomy.Results. In two months after the surgery, the patient’s uncorrected visual acuity rose from 0.15 to 1.0; the spherical component of refraction changed from -3.5 to +1.0 D, the cylindrical component of refraction fell from 1.75 to 0.25 D. Aberrometry demonstrated a decrease of RMS from 2.19 to 0.61 D, Total HOAs from 2.281 to 0.829; Tilt from 0.406 to 0.313; HOA from 1.152 to 0.247, Coma from 0.298 to 0.124, Trefoil from 1.088 to 0.094, SA from 0,127 to 0,021.Conclusion. The clinical case demonstrates the expediency and efficiency of corneal remodeling for the rehabilitation of induced errors of the corneal surface by excimer laser correction of vision based on PTK (Flex scan) + FinalFit after corneal refractive surgery.


2021 ◽  
Author(s):  
Ermano M Alves ◽  
Adriana F Lyra ◽  
Manuela Tenório ◽  
Natália Mesquita ◽  
Carolina Bacelar ◽  
...  

Abstract Background: Wavefront-optimized laser-assisted in situ keratomileusis (LASIK) ablation is the most commonly performed procedure in refractive surgery, but new technologies have become available. Our goal was to compare topography-guided (Contoura) and asphericity-guided (Custom-Q) customized ablation treatments for the correction of myopia with or without astigmatism.Methods: This prospective, randomized, double-blind, contralateral eye study included 60 eyes of 30 patients with myopia or myopic astigmatism requiring femtosecond LASIK (FemtoLASIK) treatment. For each patient, one eye was randomized to undergo Contoura treatment, and the other underwent Custom-Q abaltion. Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refractive spherical equivalent (MRSE), sphere (SPH), cylinder (CYL), 6.0-mm total corneal aberration root mean square (RMS), coma (COMA), trefoil (TREF), and spherical aberration (SA) were measured and analysed after a 1-year follow-up.Results: The UDVA was -0.08 ±0.06 logMAR in Contoura eyes and -0.08 ± 0.05 logMAR in Custom-Q eyes (p = 0.309) after 12 months. Twenty-five eyes (83%) in the Contoura group and twenty-six eyes (87%) in the Custom-Q group had a UDVA of 20/16 at the end of 12 months, and 100% of eyes in both groups reached a UDVA of 20/25 or better. Ninety and 100% of eyes in the Contoura and Custom-Q groups, respectively, achieved a residual CYL ≤0.50 D (p=0.237). No statistically significant difference was observed between the surgical techniques in the preoperative to 1-year postoperative changes for any of the parameters evaluated (MRSE, CYL, RMS, DEF, COMA, TREF, and SA).Conclusions: The Contoura and Custom-Q techniques yielded excellent visual and refractive results, but the evidence did not reveal any clear differences between these two methods after one year of follow-up. Trial registration: RBR-8rs5kt Myopia and Astigmatism Topography-guided Refractive Surgery by Contoura Method Versus Customized by Asphericity in Contralateral Eyes: A prospective Double-blind Randomized Study. UTN code: U111-1243-7257


2007 ◽  
Vol 23 (5) ◽  
pp. 447-455 ◽  
Author(s):  
Elisa Vuori ◽  
Timo M T Tervo ◽  
Martti V A Holopainen ◽  
Juha M Holopainen

2014 ◽  
Vol 179 (1) ◽  
pp. 76-80 ◽  
Author(s):  
Scott F. McClellan ◽  
James S. McGhee ◽  
John H. Boden ◽  
Robert W. Davis ◽  
Paula E. Young ◽  
...  

2018 ◽  
Vol 2018 ◽  
pp. 1-6 ◽  
Author(s):  
Takashi Kojima ◽  
Yoshihiro Kitazawa ◽  
Tomoaki Nakamura ◽  
Masahide Takahashi ◽  
Kazutaka Kamiya ◽  
...  

Purpose. To compare the visual and refractive outcomes and night vision performance questionnaire results between V4c and V5 implantable Collamer lenses in a prospective, randomized, multicenter study.Settings. Four refractive surgery centers.Design. Prospective randomized multicenter single-masked comparative study.Methods. Twenty-three patients were enrolled in this study. A conventional V4c model (EVO Visian ICL) was implanted in one eye, and a V5 model (EVO+ Visian ICL), which has a larger optic diameter than the V4c model, was implanted in the contralateral eye. The uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA) were evaluated before and 6 months after surgery. At 6 months after surgery, a questionnaire on night vision disturbances was administered. The efficacy, safety, and predictability of the two implanted ICL models were compared.Results. There were no significant differences in the postoperative UDVA and CDVA between the two ICL models. The mean efficacy indexes for the V4c and V5 lenses were 1.16 ± 0.22 and 1.03 ± 0.23, respectively. The mean safety indexes of the V4c and V5 lenses were 1.21 ± 0.20 and 1.19 ± 0.20, respectively. The night vision performance questionnaire revealed that 7 patients (37%) noticed a difference in visual performance between the eyes, and all of them reported that they could see better at night with the V5-implanted eye compared with the V4c-implanted eye.Conclusion. The V4c and V5 ICL models achieved similar visual and refractive outcomes, whereas the V5 model showed a possible advantage in reducing night vision disturbances.


2000 ◽  
Vol 129 (6) ◽  
pp. 752-758 ◽  
Author(s):  
John A Hovanesian ◽  
Sujal S Shah ◽  
Tania Onclinx ◽  
Robert K Maloney

Author(s):  
Majid Moshirfar ◽  
William D. Wagner ◽  
Steven H. Linn ◽  
Tanner W. Brown ◽  
Jackson L. Goldberg ◽  
...  

Purpose: The purpose of this study was to evaluate the risk of recurrence of optic neuritis after corneal refractive surgery in patients with a history of optic neuritis and to examine the safety and efficacy of the procedure in this population. Methods: This was a retrospective chart review of patients with a history of optic neuritis who underwent laser-assisted in situ keratomileusis (LASIK) or photorefractive keratectomy (PRK) at a single tertiary center from June 1996 to December 2014. Fifteen eyes of 14 patients were included in this study. Visual acuity before and after the surgery was recorded. Patients were followed-up for over five years postoperatively for the recurrence of optic neuritis. Results: The average LogMAR best corrected visual acuity (BCVA) preoperatively was 0.12 ± 0.19 (–0.10 to 0.60) and postoperatively was 0.06 ± 0.10 (–0.10 to 0.30). No eyes lost lines of BCVA. The average LogMAR uncorrected distance visual acuity (UDVA) after surgery was 0.12 ± 0.13 (0.00 to 0.48). Twenty-eight percent of patients reached a UDVA of 20/20 or better after refractive surgery. Optic neuritis recurred in 3/15 (20%) eyes and 3/14 patients (21%). Conclusion: While corneal refractive procedures appear safe in patients with a history of optic neuritis, our data suggest that their efficacy may be reduced.


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