Three-year outcomes after high hyperopia correction using photorefractive keratectomy with a large ablation zone

AimTo evaluate refractive and visual outcomes of photorefractive keratectomy (PRK) to treat high hyperopia using an aberration-neutral profile and large ablation zone.MethodsThis was a retrospective, consecutive observational case series at the Oftalmika Eye Hospital, Bydgoszcz, Poland. We included 51 consecutive eyes of 34 patients who underwent alcohol-assisted PRK to correct hyperopia within the range of +3.6 to +6.15 D (mean+4.61±0.67 D). Procedures were performed with an Amaris 750S excimer laser (Schwind eye-tech-solutions GmbH, Kleinostheim, Germany) using an aberration-neutral profile and a 10 mm total ablation zone. Refractive results, predictability, safety and efficacy were evaluated 3 years postoperatively.ResultsAt 1-year postsurgery, the mean manifest refraction spherical equivalent (MRSE) was −0.002±0.43 D and mean cylinder was −0.181±0.31 D, while the values were +0.09±0.46 D and −0.15±0.26 D, respectively, at 2 years (MRSE p<0.001) and +0.15±0.44 D and −0.15±0.26 D, respectively, at 3 years (MRSE p<0.001). 78% of eyes were within ±0.50 D of the attempted spherical equivalent correction. Three years postoperatively, 22% of eyes lost one line of corrected distance visual acuity and 27% gained a line or two. The change in the mean corneal spherical aberrations for the 6 mm zone was from 0.27±0.07 to 0.08±0.13 µm.ConclusionsHigh hyperopia correction with PRK using an aberration-neutral profile and large ablation zone provides good efficacy, safety, predictability and visual outcomes. Relatively low change of corneal spherical aberrations and low increase of hyperopia in the first three postoperative years were observed.

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Prospective comparison of chilled versus room temperature saline irrigation in alcohol-assisted photorefractive keratectomy

Nepalese Journal of Ophthalmology ◽

10.3126/nepjoph.v5i2.8706 ◽

2013 ◽

Vol 5 (2) ◽

pp. 154-160 ◽

Cited By ~ 4

Author(s):

Marcus C Neuffer ◽

YM Khalifa ◽

M Moshirfar ◽

MD Mifflin

Keyword(s):

Ocular Surface ◽

Room Temperature ◽

Photorefractive Keratectomy ◽

Spherical Equivalent ◽

Saline Irrigation ◽

Prospective Comparison ◽

Significant Difference ◽

Manifest Refraction ◽

The Mean ◽

Contralateral Eye

Introduction: Chilled saline is commonly used to irrigate the ocular surface after photorefractive keratectomy (PRK) and is often considered by the patients to be uncomfortable. Room temperature (non-chilled) saline may be a safe and less painful alternative. Objectives: To compare pain and visual outcomes after irrigating the ocular surface with chilled saline versus room temperature saline in alcohol assisted PRK. Materials and methods: In this prospective, single-masked, randomized, contralateral eye study, myopic eyes were treated with PRK. Immediately after laser ablation one eye was irrigated with chilled saline and the other with non-chilled saline. Primary outcomes measured were pain, haze, uncorrected (UCVA) and best-corrected (BCVA) visual acuities, and manifest refraction. Results: Each group comprised of 40 eyes. There was no significant difference in pain between the groups at any point during five days after surgery. At 6 months the mean UCVA was -0.08 logMAR ± .077 [SD] (20/17) and -0.07 ± .074 logMAR (20/17) in the chilled and non-chilled groups respectively (p =.35). Both groups achieved 95% UCVA of 20/20 or better. The manifest refraction spherical equivalent (MRSE) was -0.05 ± 0.21 D and -0.025 ± 0.27 D respectively (p = .79). There were no lines lost of BCVA and no haze observed. Similar outcomes were observed with regard to pain and vision in both groups. Conclusion: The use of room temperature saline irrigation during PRK appears to be safe and effective. Nepal J Ophthalmol 2013; 5(10): 154-160 DOI: http://dx.doi.org/10.3126/nepjoph.v5i2.8706

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Outcomes of a 320-degree intrastromal corneal ring segment implantation for keratoconus: Results of a 6-month follow-up

European Journal of Ophthalmology ◽

10.1177/1120672118818018 ◽

2018 ◽

Vol 30 (1) ◽

pp. 139-146 ◽

Cited By ~ 3

Author(s):

Guilherme Andrade do Nascimento Rocha ◽

Paulo Ferrara de Almeida Cunha ◽

Leonardo Torquetti Costa ◽

Luciene Barbosa de Sousa

Keyword(s):

Visual Acuity ◽

Spherical Equivalent ◽

Distance Visual Acuity ◽

Uncorrected Distance Visual Acuity ◽

Intrastromal Corneal Ring ◽

Corrected Distance Visual Acuity ◽

Ring Segment ◽

The Mean ◽

Corneal Tomography

Importance: This study shows that a newer long-arc length intrastromal corneal ring segment is efficient and safe for keratoconus treatment. Background: To evaluate visual, tomographic results and complications of a 320-degree intrastromal corneal ring segment implantation with the femtosecond laser for keratoconus treatment. Design: A prospective, nonrandomized, and interventional study. Participants: A total of 34 eyes of 31 patients diagnosed with keratoconus were enrolled. Methods: Patients were divided into two groups based on the strategy used for 320-degree intrastromal corneal ring segment thickness selection. In one group, this selection was based on spherical equivalent (SE group) and in the other on the mean asphericity (Q group). The uncorrected and corrected distance visual acuities, spherical equivalent, K1, K2, Km, Kmax, and mean asphericity ( Q) on corneal tomography were evaluated preoperatively and at 3 and 6 months postoperatively. For astigmatism improvement, we analyzed the corneal tomographic vectorial astigmatism change preoperatively and at 6 months postoperatively. The mean follow-up period was 6.63 ± 0.96 months. Results: The mean uncorrected distance visual acuity and corrected distance visual acuity improved with a significant spherical equivalent improvement ( p < 0.05), with no differences between the 320-degree intrastromal corneal ring segment groups. All corneal tomographic parameters improved significantly ( p < 0.05) between the preoperative and postoperative intervals, with a significant better performance when we used spherical equivalent for the 320-degree intrastromal corneal ring segment thickness selection. Finally, the mean vectorial corneal tomographic astigmatism significantly improved after 6 months, again with no differences between groups. Conclusion: This study suggests that implanting a 320-degree intrastromal corneal ring segment is a safe and effective procedure for treating patients with keratoconus. It also suggests that for thickness selection spherical equivalent is the better strategy.

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Comparison of visual outcomes after implantation of AtLisa tri 839 MP and Symfony intraocular lenses

International Ophthalmology ◽

10.1007/s10792-020-01435-z ◽

2020 ◽

Vol 40 (10) ◽

pp. 2553-2562

Author(s):

Wojciech Lubiński ◽

Karolina Podborączyńska-Jodko ◽

Marta Kirkiewicz ◽

Maciej Mularczyk ◽

Michał Post

Keyword(s):

Case Series ◽

Cataract Extraction ◽

Intraocular Lenses ◽

Group Differences ◽

Difficult Situation ◽

Iol Implantation ◽

Visual Outcomes ◽

Defocus Curve ◽

The Mean ◽

Prospective Case Series

Abstract Purpose To compare visual outcomes after implantation of AtLisa tri 839 MP and Symfony intraocular lenses (IOLs). Methods All subjects underwent sequential bilateral cataract extraction with AtLisa tri 839 MP or Symfony IOL implantation. The design is prospective case series. Each group consists of 20 patients (40 eyes). At 1 year postoperatively, the following parameters were analysed: binocular uncorrected visual acuity (log MAR): for distance (UDVA) at 4 m, for intermediate distances (UIVA) at 60, 70, 80 cm and for near (UNVA) at 40 cm, defocus curve, mesopic and photopic contrast sensitivities (CSs), spectacle independence, visual function test questionnaire modified VFQ-25), photopic phenomena and postoperative complications. Results In the AtLisa tri 839 MP group, the mean binocular UNVA and UIVA were significantly better than in the Symfony group (UNVA: − 0.01 ± 0.04 vs. 0.21 ± 0.15; p = 0.000; 60 cm UIVA: − 0.01 ± 0.04 vs. 0.09 ± 0.09, p = 0.001; 70 cm UIVA − 0.05 ± 0.06 vs. 0.11 ± 0.08, p = 0.002; 80 cm UIVA − 0.01 ± 0.06 vs. 0.15 ± 0.08, p = 0.019). There were no significant between-group differences in the mean binocular UDVA and CS, with one exception: the mean binocular distance CS (18 cpd) under mesopic conditions was significantly better in the Symfony group than in the AtLisa tri 839 MP group (1.39 ± 0.22 vs. 1.17 ± 0.27; p = 0.015). The defocus curve analysis revealed significant between-group differences at vergences of 2.0 to − 4.0 D (p < 0.05), except for 2.0, 1.0, 0 and − 1.5. All subjects in AtLisa tri 839 MP group and 18 subjects (90%) in Symfony group were spectacle independent. Patients from both groups highly rated their overall vision quality in the VFQ-25 (1.67 ± 0.47 vs. 1.85 ± 0.5 in the Symfony and AtLisa tri 839 MP group, respectively, p = NS). The scores for daytime driving (1.00 ± 0.00 vs. 1.21 ± 0.36; p = 0.002), night driving (1.57 ± 0.55 vs. 2.13 ± 1.15; p = 0.027) and difficult situation driving (1.14 ± 0.31 vs. 1.53 ± 0.56; p = 0.049) were significantly better in the AtLisa tri 839 MP group than in the Symfony group. The incidence and perception level of halo and glare were significantly reduced (p = 0.00) in the Symfony group as compared to the AtLisa tri 839 MP group. The postoperative course was uneventful in all subjects. Conclusions Visual outcomes achieved with both IOLs are comparable. In both groups, 90% of patients achieved spectacle independence. Whereas the AtLisa tri 839 MP IOL implantation was associated with slightly better intermediate distance VA and significantly better near VA, photic phenomena were less perceived by patients with Symfony IOLs.

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Reversal of Myopic Correction for Patients Intolerant to LASIK

Journal of Ophthalmology ◽

10.1155/2021/7113676 ◽

2021 ◽

Vol 2021 ◽

pp. 1-8

Author(s):

Amr A. Gab-Alla

Keyword(s):

Refractive Surgery ◽

Average Duration ◽

Corneal Thickness ◽

Case Series ◽

Spherical Equivalent ◽

Efficacy And Safety ◽

Effective Option ◽

Optical Zone ◽

The Mean ◽

One Year

Purpose. To evaluate the outcome of the reversal of myopia correction in patients intolerant to LASIK. Methods. This study is a retrospective and case series of patients who decided to reverse their previous myopic LASIK correction between July 2012 and July 2020. It was conducted at a private refractive surgery centre, Ismailia, Egypt. The patients were followed up after reversal treatment for one year. Primary LASIK and reversal treatment were performed by a 500 kHz Amaris excimer laser platform. The main outcomes included refractive predictability, stability, efficacy, and safety and any reported complications. Results. This study included 48 eyes of 24 patients (6 male and 18 female patients). The average duration between the primary LASIK surgery and reversal treatment was 3.20 ± 0.30 months (range 3 to 4 months). Reversal treatment was bilateral in all patients. The mean age of the patients was 38 ± 1.9 years (range 37 to 45 yrs). After reversal, the mean postreversal cycloplegic refraction spherical equivalent was −1.82 ± 0.34 D (range −1.50 to −3.00 D). The mean ablation depth was 34.10 ± 7.36 μm (range 20 to 46 μm), and the mean of the central corneal thickness 12 months after reversal treatment was 510.2 ± 14.4 μm (range 515 to 487 μm). The mean keratometric reading was 42.6 ± 1.6 (range 42.5 to 44.8). The mean of CDVA was 0.2 ± 0.03 log MAR (range −0.10 to 0.4 log MAR). The mean optical zone of reversal treatment was 6.1 ± 0.3 mm (range 5.9 to 6.2 mm). UDVA was 0.4 log MAR in 87.5% of the patients, 0.5 log MAR in 8.3% of the patients, and 0.6 log MAR in 4.2% of the patients. CDVA remained unchanged in 83.3% of patients; 2.1% of the patients gained one line of CDVA (Snellen); 8.3% of the patients lost one line of CDVA; 6.3% of the patients lost two lines of CDVA. No cases of corneal ectasia were recorded. The only postoperative complications were flap microfolds in 3 eyes (6.25%). Conclusion. In conclusion, this study demonstrates that reversal of myopic LASIK treatment is a safe, stable, and effective option for intolerant patients.

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Femtosecond Laser Implantation of a 355-Degree Intrastromal Corneal Ring Segment in Keratoconus: A Three-Year Follow-Up

Journal of Ophthalmology ◽

10.1155/2019/6783181 ◽

2019 ◽

Vol 2019 ◽

pp. 1-7

Author(s):

Marwa Mahmoud Abdellah ◽

Hatem Gamal Ammar

Keyword(s):

Femtosecond Laser ◽

Case Series ◽

Corneal Neovascularization ◽

High Rate ◽

Spherical Equivalent ◽

Clinical Trial Registry ◽

Link Type ◽

The Mean ◽

Prospective Case Series

Purpose. To evaluate the outcomes of femtosecond laser-assisted implantation of a 355-degree intracorneal ring (ICR) (Keraring) in patients with keratoconus in the three-year follow-up. Setting. Future Femtolaser Center, Sohag, Egypt. Design. Prospective interventional case series. Patients and Methods. A prospective case series of 38 eyes of 26 patients with keratoconus had implantation of the 355-degree ICR keraring after tunnel creation with a femtosecond laser. The uncorrected visual acuities (UCVA) and best-corrected visual acuities (BCVA), sphere, cylinder, and manifest refraction spherical equivalent (SE), and mean keratometry (K), K max, and K min were evaluated preoperatively and 3, 6, 12, 24, and 36 months postoperatively, and all complications were reported. Results. 38 eyes of 26 patients with mean age 25.92 ± 5.44 years were enrolled in the study, 11 were males (42.3%). The mean UCVA improved from 0.93 ± 0.21 to 0.63 ± 0.21 logMAR (P≤0.001) and the mean BCVA from 0.67 ± 0.22 to 0.43 ± 0.26 logMAR (P<0.001). The mean sphere, cylinder, and spherical equivalent have been changed dramatically from preoperative to 3 month postoperative, which is statistically significant (P≤0.001), and the changes between 1 and 2 years and 2 and 3 years are also considerable and statistically significant; the K max and K min and K mean improved and the changes were statistically significant (P≤0.001), and the changes between one, two, and three years were also statistically significant. The safety and efficacy indices were changed through the three-year follow-up. The complications were corneal neovascularization (36.84%), corneal melting (26.3%), and ring extrusion (31.5%) at the end of the study. Conclusions. Implantation of a 355-degree intracorneal keraring using femtosecond laser improved the visual, refractive, and topographic parameters in keratoconus patients, with a high rate of ICR extrusion and instability. The study has been registered for the Pan African Clinical Trial Registry (http://www.pactr.org) database within No: PACTR201810796878908 on 29 October 2018.

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Visual outcomes after bilateral implantation of Versario intraocular lenses – six month follow-up

10.21203/rs.3.rs-1088063/v1 ◽

2021 ◽

Author(s):

Karolina Podboraczynska-Jodko ◽

Wojciech Lubiński

Keyword(s):

Postoperative Complications ◽

Case Series ◽

Intraocular Lenses ◽

Normal Range ◽

Visual Outcomes ◽

Function Test ◽

Healthy Control ◽

Defocus Curve ◽

The Mean

Abstract PurposeTo study visual outcomes after implantation of Versario intraocular lenses (IOLs) Patients and MethodsIn 20 selected patients (40 eyes) uneventful, bilateral cataract surgeries with implantation of trifocal Versario (IOLs) were performed. Designprospective case series. Six months after surgery the following parameters were analysed: binocular uncorrected visual acuities (log MAR): for distance (UDVA) at 4 m, for intermediate (UIVA) at 60, 70, 80 cm and for near (UNVA) at 40 cm, photopic defocus curve, mesopic and photopic contrast sensitivities (CSs), spectacle independence, visual function test questionnaire (modified VFQ-25), subjective symptoms and postoperative complications. ResultsSix months after surgery, the mean of binocular visual acuities were as follows: UDVA: -0.12 ± 0.08; UIVA (60 cm): +0.07 ± 0.10, (70 cm): +0.05 ± 0.11, (80cm): +0.07 ± 0.09; UNVA (40cm): +0.12 ± 0.08. CSs in mesopic and scotopic conditions for distance and photopic for near were between normal range of age- match healthy control. All patients were spectacle independent. General satisfaction was high and equal 9.37±0.83. No severe glare and halo were detected. There were no postoperative complications. ConclusionsThe bimanual MICS with the Versario lenses implantation was a safe and effective method for patients who want to be spectacle independent at different distances.

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Visual outcomes for surgical treatment of large and giant carotid ophthalmic segment aneurysms: a case series utilizing retrograde suction decompression (the “Dallas technique”)

Journal of Neurosurgery ◽

10.3171/2013.2.jns12735 ◽

2013 ◽

Vol 118 (5) ◽

pp. 937-946 ◽

Cited By ~ 30

Author(s):

Thomas Mattingly ◽

Max K. Kole ◽

David Nicolle ◽

Mel Boulton ◽

David Pelz ◽

...

Keyword(s):

Case Series ◽

Visual Symptoms ◽

Visual Outcomes ◽

Before And After ◽

Specific Outcome ◽

The Mean ◽

Large And Giant Aneurysms ◽

Decompression Procedure ◽

Ophthalmic Segment Aneurysms ◽

Endovascular Technology

ObjectThe authors report their results in a series of large or giant carotid ophthalmic segment aneurysms clipped using retrograde suction decompression.MethodsA retrospective review of clinical data and treatment summaries was performed for 18 patients with large or giant carotid artery ophthalmic segment aneurysms managed operatively via retrograde suction decompression. Visual outcomes, Glasgow Outcome Scale (GOS) scores, and operative complications were determined. Postoperative angiography was assessed.ResultsDuring a 17-year period, 18 patients underwent surgery performed using retrograde suction decompression. The mean aneurysm size was 26 mm. Three patients presented with subarachnoid hemorrhage. Fourteen of 18 patients presented with visual symptoms. Eleven (79%) of these 14 patients experienced visual improvement and the remaining 3 (21%) experienced worsened vision after surgery. Of 3 patients without visual symptoms and a complete visual examination before and after surgery, 1 had visual worsening postoperatively. One aneurysm required trapping and bypass, and all others could be clipped. Postoperative angiography demonstrated complete occlusion in 9 of 17 clipped aneurysms and neck remnants in the other 8 clipped aneurysms. One (5.5%) of 18 patients experienced a stroke. Eighteen patients had a GOS score of 5 (good outcome), and 1 patient had a GOS score of 4 (moderately disabled). There were no deaths. There was no morbidity related to the second incision or decompression procedure. Prolonged improvement did occur, and even in some cases of visual worsening in 1 eye, the overall vision did improve enough to allow driving.ConclusionsRetrograde suction decompression greatly facilitates surgical clipping for large and giant aneurysms of the ophthalmic segment. Visual preservation and improvement occur in the majority of these cases and is an important outcome measure. Developing endovascular technology must show equivalence or superiority to surgery for this specific outcome.

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Outcomes of Wavefront-Optimized Laser-Assisted In-Situ Keratomileusis and Photorefractive Keratectomy for correction of Myopia and Myopic Astigmatism over One Year Follow-Up

The Open Ophthalmology Journal ◽

10.2174/1874364101812010256 ◽

2018 ◽

Vol 12 (1) ◽

pp. 256-263 ◽

Cited By ~ 1

Author(s):

Mohammad M. Shehadeh ◽

Mohammad T. Akkawi ◽

Ammar A. Aghbar ◽

Muna T. Musmar ◽

Malak N Khabbas ◽

...

Keyword(s):

Visual Acuity ◽

Excimer Laser ◽

Photorefractive Keratectomy ◽

Distance Visual Acuity ◽

Visual Outcomes ◽

Corrected Distance Visual Acuity ◽

One Year ◽

Myopic Astigmatism

Background: Laser corneal refractive surgery suits, technology and nomograms are improving with time. This may improve the refractive and visual outcomes of the patients. Objectives: To evaluate the safety, efficacy, stability, and predictability of wavefront-optimized photorefractive keratectomy and Laser-assisted in-situ keratomileusis in patients with myopia and myopic astigmatism over 1-year using WaveLight® EX500 Excimer Laser machine. Methods: In this prospective cohort study, refractive and visual outcomes in 596 eyes (365 patients), either having myopia or myopic astigmatism were assessed. Patients were divided into Two groups: 1) Patients who underwent PRK (53 eyes have myopia and 217 eyes have myopic astigmatism), 2) Patients who underwent LASIK (53 eyes have myopia and 273 eyes have myopic astigmatism). Results: At 12 months postoperatively 94.3% of the myopic patients reached their preoperative best corrected distance visual acuity at the final one year follow up visit post PRK and LASIK. In patients with myopic astigmatism who underwent LASIK and PRK, 95.2%, and 96.3% of the patients reached their preoperative best corrected distance visual acuity at the final one year follow up visit post LASIK and PRK, respectively. The efficacy and safety indices were 1.00 or more for all groups with no eye lost any line of best corrected distance visual acuity. Conclusion: Our study results confirm the excellent efficacy, safety, good predictability and stability of myopia / myopic astigmatism correction by either wavefront- optimized LASIK or PRK over 1-year follow-up without significant differences between them using the WaveLight® EX500 excimer laser system.

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Clinical Effect and Rotational Stability of TICL in the Treatment of Myopic Astigmatism

Journal of Ophthalmology ◽

10.1155/2020/3095302 ◽

2020 ◽

Vol 2020 ◽

pp. 1-7

Author(s):

Manhui Zhu ◽

Linling Zhu ◽

Qiujian Zhu ◽

Cailian Xu ◽

Peng Yu ◽

...

Keyword(s):

Risk Factors ◽

Visual Acuity ◽

Rotational Stability ◽

Spherical Equivalent ◽

Implantable Collamer Lens ◽

Manifest Refraction ◽

Efficacy Index ◽

The Mean ◽

Myopic Astigmatism ◽

High Myopic Astigmatism

Purpose. To investigate the clinical outcomes and possible risk factors associated with rotational stability after the implantation of a V4c toric implantable Collamer lens (TICL) for the correction of moderate to high myopic astigmatism. Methods. A total of 112 eyes of 66 patients with moderate to high myopic astigmatism underwent TICL implantation. All patients were followed up for more than 1 year. The uncorrected and best-corrected visual acuity (UCVA and BCVA), astigmatism and spherical equivalent, intraocular pressure, vault, endothelial cell morphometry, and rotation of the TICL axis were assessed at l day, 1 week, 1 month, 3 months, 6 months, and 12 months postoperatively. Postoperative rotation was defined as the angle between the intended axis and the achieved axis. Regression analysis was used to investigate the possible risk factors for TICL rotation postoperatively. Results. The mean efficacy index and safety index 12 months postoperatively were 1.03 ± 0.09 and 1.05 ± 0.10, respectively. All patients had the same or better visual acuity than preoperatively. The mean astigmatism value decreased from −1.86 ± 0.79 D preoperatively to −0.37 ± 0.35 D. The mean absolute axis deviation of the TICL at the last follow-up was 2.75 ± 2.04° (range, 0°∼11°). The mean manifest refraction spherical equivalent (MRSE) changed from -9.04 ± 2.67 D preoperatively to −0.67 ± 0.51 D postoperatively. The logistic regression demonstrated that the absolute degree of TICL rotation had a significant association with the fixation angle of the TICL and the size of the lens ( P = 0.003 , P = 0.026 , resp.). Conclusion. The results of our study support that TICL implantation is safe, effective, and predictable in the treatment of moderate to high myopic astigmatism, with relatively good postoperative rotational stability.

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Comparison of 6.0 mm versus 6.5 mm Optical Zone on Visual Outcomes after LASIK

Journal of Clinical Medicine ◽

10.3390/jcm10173776 ◽

2021 ◽

Vol 10 (17) ◽

pp. 3776

Author(s):

Majid Moshirfar ◽

Rachel Huynh ◽

Nour Bundogji ◽

Alyson N. Tukan ◽

Thomas M. Sant ◽

...

Keyword(s):

Visual Acuity ◽

Laser System ◽

Spherical Equivalent ◽

Distance Visual Acuity ◽

Visual Outcomes ◽

Refractive Outcomes ◽

Uncorrected Distance Visual Acuity ◽

Corrected Distance Visual Acuity ◽

Optical Zone ◽

The Difference

Previous studies have demonstrated safety and efficacy using 6.0 and 6.5 mm optical zones in the WaveLight EX500 Excimer Laser System but have not evaluated if differing optical zone sizes influence refractive outcomes. This study examines visual outcomes between two study populations undergoing LASIK with either a 6.0 mm (1332 patients) or 6.5 mm (1332 patients) optical zone. Outcomes were further stratified by severity of myopia (low, moderate, and high) and astigmatism (low and high). Patients were matched by age and preoperative manifest sphere and cylinder. Postoperative measurements were then compared. The 6.5 mm group demonstrated better postoperative manifest refractive spherical equivalent (MRSE), manifest sphere, and absolute value of the difference in actual and target spherical equivalent refraction (|∆ SEQ|), within the total population, moderate myopia, and low astigmatism groups, but this did not lead to improved postoperative uncorrected distance visual acuity (UDVA) or best corrected distance visual acuity (CDVA). Though astigmatic correction and postoperative angle of error were similar between optical zone sizes, they were significantly worse with high myopia. Overall, this study demonstrates differences in visual outcomes between the 6.0 and 6.5 mm optical zone sizes that may warrant consideration; however, essentially, the results are comparable between them.

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