distance visual acuity
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2021 ◽  
Vol 8 ◽  
Author(s):  
Kazutaka Kamiya ◽  
Kimiya Shimizu ◽  
Masahide Takahashi ◽  
Wakako Ando ◽  
Hideki Hayakawa ◽  
...  

Purpose: To assess the 8-year clinical outcomes of implantation of an implantable collamer lens (ICL) with a central port (KS-Aquaport; EVO-ICL) for moderate to high myopia and myopic astigmatism.Methods: This retrospective study comprised a total of 177 eyes of 106 patients with spherical equivalents of −7.99 ± 3.33 D [mean ± standard deviation], who underwent EVO-ICL implantation. We evaluated the safety, efficacy, predictability, stability, and adverse events of the surgery, at 1 month, and 1, 2, 4, 6, and 8 years postoperatively.Results: The logarithm of the minimal angle of resolution (LogMAR) uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA) were −0.07 ± 0.17 and −0.20 ± 0.09, respectively, at 8 years postoperatively. The safety and efficacy indices were 1.18 ± 0.24 and 0.89 ± 0.28, respectively. At 8 years, 83 and 93% eyes were within ± 0.5 D and ± 1.0 D of the targeted correction, respectively. Change in manifest refraction from 1 month to 8 years postoperatively was −0.13 ± 0.30 D. Three eyes (1.7%) that developed cataracts had a slight pre-existing peripheral anterior subcapsular cataract formation required simultaneous ICL extraction and cataract surgery at 2 or 3 years or ICL size change (1 size up) at 7 years postoperatively. We found that neither significant intraocular pressure (IOP) rise (including pupillary block) nor significant endothelial cell loss occurred in any case throughout the 8-year observation period.Conclusions: Current ICL implantation with central port technology offered good continuous outcomes for all measures of safety, efficacy, predictability, and stability for correcting moderate to high myopic errors over a long period, thereby suggesting its long-term viability as a surgical approach for the treatment of such eyes.


2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Yuan Wu ◽  
Shuhan Wang ◽  
Guiqin Wang ◽  
Shaozhen Zhao ◽  
Ruihua Wei ◽  
...  

Objective. To compare the corneal asphericity and higher-order aberrations (HOAs) of femtosecond laser-assisted in situ keratomileusis (FS-LASIK) with Smart Pulse Technology (SPT) assisted transepithelial photorefractive keratectomy (Trans-PRK) for myopia and myopic astigmatism correction. Methods. This prospective study analyzed 88 eyes of 44 patients treated with FS-LASIK and 64 eyes of 32 patients treated with Trans-PRK. All eyes had low to moderate myopia with or without astigmatism (spherical equivalent (SE) <−6.00 diopters). The uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), SE, asphericity (Q value) of the anterior corneal surface, index of surface variance (ISV), corneal higher-order aberrations (HOAs), vertical coma (Z3−1), horizontal coma (Z31), and spherical aberration (Z40) over a 6 mm diameter central corneal zone diameter were evaluated preoperatively and 1, 3, and 6 months postoperatively. Results. At 6 months, the UDVA and SE were −0.14 ± 0.06 and 0.33 ± 0.33D in FS-LASIK and −0.15 ± 0.06 and 0.35 ± 0.37D in Trans-PRK. There was no difference between the two groups in the postoperative UDVA and SE ( P > 0.05 ). After FS-LASIK and Trans-PRK, the Q values in the 6, 7, 8, and 9 mm zones and ISV of the anterior corneal surface significantly increased ( P < 0.001 ). At 1, 3, and 6 months after surgery, corneal HOA, Z3-1, Z31, and Z40 in both groups were significantly increased compared with those before surgery, with statistically significant differences ( P < 0.001 ). At 1, 3, and 6 months after surgery, the Z3−1 of the Trans-PRK group was significantly lower than that of the FS-LASIK group ( P < 0.001 ). ΔHOA and ΔZ40 were dramatically correlated with the ΔQ value for both FS-LASIK and Trans-PRK procedures. The ΔQ was significantly correlated with the preoperative SE, AD, and AD/CCT after both two procedures (all P < 0.001 ). Conclusions. Both FS-LASIK and Trans-PRK caused the anterior corneal surface to become flatter, and the morphology of the corneal surface was irregular. Corneal HOAs were significantly increased after the two procedures. Trans-PRK using SPT introduced less corneal vertical coma than FS-LASIK. Corneal asphericity changes contributed to the corneal aberrations changes following FS-LASIK and Trans-PRK.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Cristina Ariadna Nicula ◽  
Dorin Nicula ◽  
Sorana D. Bolboacă ◽  
Adriana Elena Bulboacă

Abstract Purpose To report the visual and refractive outcomes of small incision lenticule extraction ReLEX (SMILE) technique using VisuMax femtosecond laser in myopia and myopic astigmatism patients. Material and methods A non-randomized clinical study has been conducted on patients with myopia and myopic astigmatism who underwent ReLEX SMILE technique, using the Zeiss VisuMax Laser system (Carl Zeiss Meditec AG, Jena, Germany) at Oculens Clinic, Cluj-Napoca, Romania. Patients older than 18 years, with ocular astigmatism up to -5 diopters (D), spherical equivalent up to -10.00 D, corrected distance visual acuity (CDVA) of 0.3 or better before the surgery, stable refraction for one year, and with a minimum calculated post operator residual stromal bed of 250μ were included in the study. Results The study involved a total of 25 myopic eyes (median of sphere diopters equal with -4D) and 67 myopic astigmatic eyes (median of cylinder diopters equal with -1.5 D). The mean refractive spherical equivalent (MRSE) on patients with myopic eyes reduced from -4.25D (median) to -0.5D at one month follow-up, -0.25 D at 6 and 12 months. The mean refractive spherical equivalent (MRSE) on patients with astigmatic myopic eyes reduced from-6.25 D to -0.67 D at one month, -0.62 D at six and twelve months. The value of sphere decreased postoperatively on myopic eyes with a median of -0.25D at one, six and twelve months. The value of cylinder decreased postoperatively on myopic astigmatic eyes with a median of -0.50 D at one month, -0.25 D at six months and -0.50 D at 12 months. At 6 and 12 months, 20 (80.0%) of myopic eyes were maintained within ±0.5 D and 22 (88.0%) with ±1D. On both groups (myopic eyes and myopic astigmatic eyes), statistically significant differences were observed when the keratometric baseline values were compared to each follow-up (P-values < 0.0001), without any significant differences between follow-ups (P-values>0.15). At 1-month follow-up, uncorrected distance visual acuity (UDVA) was better than or equal to 0.5 in 88.0% of myopic eyes and 82.1% of myopic astigmatic eyes. UDVA remained stable in all cases of myopic eyes at six months and the percentage increased at 92.0% in myopic eyes. UDVA slightly increased at 6-months (85.1%) and remained at the same value at 12-months in myopic astigmatism eyes. Conclusions SMILE proved an effective and safe refractive corneal procedure and provided a predictable and stable correction of myopia and myopic astigmatism. SMILE technique demonstrated very good outcomes in terms of keratometric, cylinder, spherical measurements.


Optics ◽  
2021 ◽  
Vol 2 (4) ◽  
pp. 266-275
Author(s):  
Diego de Ortueta ◽  
Dennis von Rüden ◽  
Samuel Arba-Mosquera

Transepithelial photorefractive keratectomy (TransPRK) is an established surface ablation technique used to correct refractive errors. Using anterior segment optical coherence (AS-OCT), it is now possible to measure the epithelium thickness and input these data into the laser platform. In this study, we explore whether better results were obtained in this way. To this end, we retrospectively analyze the results from a low-myopia group treated with a customized epithelium thickness, as measured using AS-OCT, and compare them with the results from a group treated with an optimized standard epithelium thickness. The customized epithelium profile group contains more eyes with vision better than 20/20, and more eyes in this group gain one line of corrected distance visual acuity (CDVA). In conclusion, with the customized epithelium thickness, we obtain superior results using TransPRK in low-myopia corrections.


2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Hao Liu ◽  
Denghao Dong ◽  
Chunlin Chen ◽  
Jian Ye

Purpose. To investigate the effects of two different surgical methods of implantable collamer lens (ICL) implantation on the operation time, visual outcomes, corneal endothelial cell count, and intraocular pressure (IOP). Methods. This was a contralateral eye comparison study, a total of 192 eyes from 96 patients were included, and the two eyes from the same patient were randomly assigned to two groups (group 1 and group 2, with 96 eyes in each group). In group 1, after making the corneal incision, ophthalmic viscosurgical devices (OVDs) were first injected into the anterior chamber followed by ICL implantation. In group 2, the ICL was first implanted into the anterior chamber followed by OVDs injection. The operation time, uncorrected distance visual acuity, corrected distance visual acuity, spherical equivalent, corneal endothelial cell count, and IOP were recorded and analyzed. Results. The operative time in group 1 was significantly longer than that in group 2 ( P  = 0.002 < 0.05). There were significant differences between IOP measured 2 hours following surgery of the two groups ( P  = 0.026 < 0.05), Furthermore, the rate of IOP change 2 hours following the operation was significantly higher in group 1 than in group 2 ( P  = 0.019 < 0.05). There were significant differences in the anterior chamber angle 2 hours after surgery compared with that before surgery in both groups ( P  = 0.014 < 0.05 and P  = 0.029 < 0.05, respectively). No significant differences were observed in the other parameters measured (all P  > 0.05). Conclusion. The two ICL implantation methods had similar clinical outcomes and effects on the corneal endothelial cell count. Additionally, the implantation of an intraocular lens prior to injecting OVDs reduces the operation time and lowers the rate of IOP rise in the early postoperative period, making it safe and effective for ICL implantation.


2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Abdelrahman Salman ◽  
Taym Darwish ◽  
Marwan Ghabra ◽  
Obeda Kailani ◽  
Hussam Khalil ◽  
...  

Aim. To assess the efficacy and safety of accelerated corneal cross-linking in the treatment of pediatric keratoconus. Method. In this retrospective case series, 29 eyes of 20 pediatric patients with keratoconus underwent accelerated corneal cross-linking. Treatment was delivered at 10 mW/cm2 for 9 minutes with a total dose of 5.4 J/cm2. Clinical evaluation included visual acuities and refractive and Scheimpflug corneal tomography assessments. All patients with a minimum follow-up duration of 24 months were included in the study. Results. Mean ± standard deviation age was 15.41 ± 2.13 years (range: 8 to 18 years). Uncorrected distance visual acuity improved significantly from 0.56 ± 0.28 to 0.42 ± 0.29 logMAR P = 0.0003 , and corrected distance visual acuity improved significantly from 0.34 ± 0.23 to 0.28 ± 0.22 logMAR P = 0.014 . The mean manifest refraction spherical equivalent value was significantly reduced (−0.59 ± 0.95 D, P = 0.0024 ). While mean flat keratometry and steep keratometry values were not significantly altered ( P > 0.05 for both), the mean maximum keratometry value was significantly decreased from 56.97 ± 5.24 D preoperatively to 55.84 ± 5.37 D at 24 months postoperatively P = 0.003 . Maximum keratometry had progressed by >1 D in two eyes (6.89%). Permanent corneal haze was reported in one case (3.44%). Conclusion. Our 24-month follow-up demonstrated that accelerated corneal cross-linking appears to halt the progression of keratoconus in pediatric patients without apparent complications. Uncorrected and corrected distance visual acuities were also improved.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Byunghoon Chung ◽  
Joon Hyun Kim ◽  
David S. Y. Kang ◽  
Dong Jun Kang ◽  
Eung Kweon Kim ◽  
...  

Abstract Background To investigate the surgical outcomes of implantable collamer lens (ICL) implantation in eyes with residual myopia after primary laser vision correction (LVC) surgeries. Methods This study included patients who underwent ICL implantation and had a history of LVC surgery, including photorefractive keratectomy (PRK) or laser-assisted in situ keratomileusis (LASIK). Visual acuity and refractive error were assessed pre and 3-months postoperatively and the efficacy and safety indices calculated accordingly. Results A total of 30 eyes of 17 patients were included in this study. At 3 months, the mean logMAR uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and spherical equivalent were − 0.03 ± 0.11 (include logMAR), − 0.04 ± 0.09 (include logMAR), and − 0.06 ± 0.33 diopters (D), respectively. The 3-month Snellen UDVA was better than 20/20 for 83% of eyes, and 97% of eyes showed an unchanged or improved CDVA after surgery. The mean efficacy and safety indices were 1.11 ± 0.22 and 1.13 ± 0.20, respectively. Further, 93 and 100% of eyes were within ±0.5 and ± 1.0 D of the attempted spherical equivalent refraction, respectively. Conclusions ICL implantation in eyes with myopic regression after previous LVC surgery showed safe, effective, and predictable outcomes. Trial registration retrospectively registered.


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


2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Xun Chen ◽  
Xuanqi Wang ◽  
Yilin Xu ◽  
Mingrui Cheng ◽  
Tian Han ◽  
...  

Abstract Background To evaluate the long-term safety, efficacy, predictability, and stability of implantable collamer lens with a central hole (EVO ICL) implantation for correcting high myopia (HM) and super high myopia (SHM). Methods This prospective study evaluated 83 eyes of 46 patients who were divided into groups based on their spherical equivalent refractive error (SE): HM group (− 12 D ≤ SE < − 6 D) and SHM group (SE < − 12 D). They were followed up for 5 years after ICL implantation; assessments of uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refractive error, axial length, intraocular pressure, corneal endothelial cell density, and vault were conducted, and a questionnaire was administered. ResuIts At 5 years postoperatively, the safety indices of the HM and SHM groups were 1.03 ± 0.10 and 1.32 ± 0.39, and the efficacy indices were 0.83 ± 0.25 and 0.86 ± 0.32, respectively. In the HM group, 60.47% and 79.07% of the eyes were within ± 0.50 D and ± 1.00 D of the attempted correction, while it was achieved for 22.50% and 47.50% of the eyes in the SHM group, respectively. The SE of the HM group decreased from  − 9.72 ± 1.41 D preoperatively to 0.04 ± 0.39 D 1 month postoperatively and − 0.67 ± 0.57 D 5 years postoperatively, while in the SHM group, it decreased from − 15.78 ± 3.06 D preoperatively to  − 0.69 ± 0.97 D 1 month postoperatively and − 1.74 ± 1.19 D 5 years postoperatively. Conclusion EVO ICL implantation is safe, effective, and predictable for correcting HM and SHM. CDVA improved more after surgery for SHM, but the growth of axial length still needs attention.


2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Shira Hed ◽  
Ran Matlov Kormas ◽  
Sagi Shashar ◽  
Boris E. Malyugin ◽  
Matthew Boyko ◽  
...  

Introduction. Keratoconus is a progressive corneal disease commonly treated by collagen cross-linking (CXL). Accelerated protocols have recently become common. This study sought to compare the outcomes of accelerated and standard CXL in terms of visual acuity, keratometry, and tomographic parameters in pediatric population. Methods. We retrospectively reviewed the files of pediatric patients who underwent standard and accelerated CXL for keratoconus in our hospital, between October 2014 and March 2018. Changes in uncorrected distance visual acuity (UCDVA), best corrected distance visual acuity (BCDVA), tomographic keratometry parameters (Kmax, Ksteep, Kflat, Kmean), and endothelial density count (EDC) were assessed before and at 6 and 12 months following treatment. The analysis included intergroup and intragroup comparisons. Results. This study included 53 eyes (44 patients). Fourteen eyes were treated with standard CXL (S-CXL, 3 mW/cm2, 30 min), while 39 underwent accelerated CXL (A-CXL, 9 mW/cm2, 10 min). Intergroup comparison found insignificant differences between groups, with the exception of better results for UCDVA in the S-CXL group after 12 months ( P  = 0.03). In this study, there was no significant difference between the two protocols postoperatively in BCDVA, Kmax, Kmean, pachymetry, or corneal astigmatism. Conclusion. A-CXL is as safe and effective as S-CXL for stabilizing progressive keratoconus in pediatric population. Larger-sample-size studies with a longer follow-up time are required. Considering the long-term results of 9 mW A-CXL and its safety and efficacy profile, it should be preferred to S-CXL for reducing treatment time and improving patients’ comfort.


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