Safety and Efficacy of Myopic LASIK performed on Thin Corneas

Purpose: The aim was to report on the visual outcomes and safety of myopic LASIK performed in patients with corneas of central thickness below average(<540μm) and normal topography. Methods: This is a retrospective cohort study conducted at a private practice setting on Mexican Hispanic patients who underwent myopic LASIK between January 2014 and January 2015. An analysis of records of patients >18 years-old with previous normal topography, stable refraction, corrected visual acuity ≥ 20/20 (Snellen), Central Corneal Thickness (CCT) < 540μm and at least 12 months follow up after surgery was conducted. The main outcome measures were standard visual outcomes (efficacy, safety, refractive stability) and Percent Tissue Altered (PTA) analysis was conducted. Results: A total of 51 patients (102 eyes) were included; 56% (n=57) were female. The mean age was 26.52 ± 8.06 (range 18-55 years) with a mean follow up of 13.9 ± 1.2 months. Preoperative CCT was 515.44 ± 17.87μm (range 452- 540μm), with a mean refractive spherical equivalent (SEQ): -4.08 ± 2.17 D (range -0.75 to -9.75 D), and mean refractive cylinder: -1.44 ± 1.29 D (range 0.00 to -6.00 D). Mean predictability of postoperative SEQ was -0.20 ± 0.40 D (range -1.25 to +1.25). Postoperative SEQ was ±0.50 D in 71%, ±1.00 D in 93% of the eyes. Postoperative uncorrected distance visual acuity was ≥20/20 in 78% and ≥20/25 in 95%. One line of CDVA was lost in 3% of the eyes, no eyes lost ≥2 lines. No ectasia cases were observed during follow-up. Conclusion: LASIK surgery in Mexican Hispanic patients with thinner than “normal” corneas (<540 μm) is safe, efficient and predictable at 1 year follow up for myopic refractive corrections with no evidence of postoperative keratectasia.

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Corneal densitometry in patients with keratoconus undergoing intrastromal Ferrara ring implantation

European Journal of Ophthalmology ◽

10.1177/11206721211020631 ◽

2021 ◽

pp. 112067212110206

Author(s):

Pablo Felipe Rodrigues ◽

Bernardo Kaplan Moscovici ◽

Guilherme Ferrara ◽

Luciano Lamazales ◽

Marcela Mara Silva Freitas ◽

...

Keyword(s):

Visual Acuity ◽

Medical Records ◽

Spherical Equivalent ◽

Interventional Study ◽

Data Comparison ◽

Corneal Densitometry ◽

Corrected Visual Acuity ◽

Ring Segment ◽

The Mean

Objective: Evaluation of central corneal densitometry changes following Ferrara corneal ring segment implantation in patients with keratoconus, especially the correlation between corneal densitometry and keratometry. Methods: Retrospective, non-comparative, interventional study based on the review of medical records of patients diagnosed with keratoconus who underwent Ferrara corneal ring segment implantation. Pre and post-operative corneal densitometry measurements obtained with Pentacam HR (Oculus, Wetzlar, Germany) were analyzed. The follow-up time was 3 months, and data comparison was made, using specific statistical analysis, with the data of 3 months postoperatively. Results: The study sample consisted of 43 eyes of 36 patients. The mean corrected visual acuity improved from 0.82 LogMAR preoperatively (SD ± 0.33) to 0.19 LogMAR (SD ± 0.13) postoperatively. The mean spherical equivalent varied from −4.63 (SD ± 3.94) preoperatively to −2.16 (SD ± 2.63) postoperatively. Asphericity varied from −0.69 (SD ± 0.32) preoperatively to −0.27 (SD ± 0.31) postoperatively. The mean maximum K was 54.01D (SD ± 3.38) preoperatively and 51.50D (SD ± 2.90) postoperatively. The mean anterior densitometric value was 18.26 (SD ± 2.03) preoperatively and 17.66 (SD ± 1.84) postoperatively. Conclusion: Corneal densitometry is an interesting technology that should be studied in keratoconus patients. Our results suggest that the corneal densitometry in the cornea’s anterior layer reduces after ICRS implantation and correlates with corneal keratometry. Further studies should be performed to increase the knowledge in this field.

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Seven years follow-up of corneal cross-linking (CXL) in pediatric patients: Evaluation of treated and untreated eye

European Journal of Ophthalmology ◽

10.1177/11206721211020632 ◽

2021 ◽

pp. 112067212110206

Author(s):

Iliya Simantov ◽

Lior Or ◽

Inbal Gazit ◽

Biana Dubinsky-Pertzov ◽

David Zadok ◽

...

Keyword(s):

Visual Acuity ◽

Pediatric Patients ◽

Pediatric Population ◽

Corneal Thickness ◽

Cross Linking ◽

Uncorrected Distance Visual Acuity ◽

Mild Reduction ◽

Change In The Mean ◽

The Mean

Background: Retrospective cohort study evaluating long term keratoconus progression amongst cross-linking (CXL) treated pediatric patients in the treated and the fellow untreated eyes. Methods: Data on 60 eyes of 30 patients, 18 years old or younger, who underwent CXL in at least one eye was collected and analyzed. Follow-up measurements taken from the treated and untreated eye up to 7 years after CXL treatment, were compared to baseline measurements. Parameters included uncorrected distance visual acuity (UCDVA), best-corrected spectacle visual acuity (BCSVA), manifest refraction, pachymetry, corneal tomography, and topography. Results: Mean age of patients was 16 ± 2.1 years. For the treated eyes, during follow-up period mean UCDVA had improved (from 0.78 ± 0.22 at baseline to 0.58 ± 0.26 logMAR at 7 years; p = 0.13), as well as mean BCSVA (from 0.23 ± 0.107 at baseline to 0.172 ± 0.05 logMAR at 7 years; p = 0.37). The mean average keratometry showed a significant flattening (from 49.95 ± 4.04 to 47.94 ± 3.3 diopters (D); p < 0.001), However there was no change in the mean maximal keratometry. The mean minimal corneal thickness (MCT) showed a significant mild reduction of 26 µm ( p = 0.006). Although statistically insignificant, the mean manifest cylinder was also reduced to 2D ( p = 0.15). During the follow-up period, eight untreated eyes (26.6%) deteriorated and underwent CXL, while only one treated eye (3.33%) required an additional CXL. Conclusion: CXL is a safe and efficient procedure in halting keratoconus progression in the pediatric population, the fellow eye needs to be carefully monitored but only a 25% of the patients will require CXL in that eye during a period of 7 years.

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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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Refractive, Topographic, and Aberrometric Results at 2-Year Follow-Up for Accelerated Corneal Cross-Link for Progressive Keratoconus

Journal of Ophthalmology ◽

10.1155/2017/5714372 ◽

2017 ◽

Vol 2017 ◽

pp. 1-6 ◽

Cited By ~ 7

Author(s):

Ercüment Bozkurt ◽

Engin Bilge Ozgurhan ◽

Betul Ilkay Sezgin Akcay ◽

Tugba Kurt ◽

Yusuf Yildirim ◽

...

Keyword(s):

Visual Acuity ◽

Spherical Aberration ◽

Corneal Thickness ◽

Corneal Topography ◽

Wavefront Aberration ◽

Distance Visual Acuity ◽

Uncorrected Distance Visual Acuity ◽

Wavefront Error ◽

The Mean

Purpose. To report the visual, refractive, and corneal topography and wavefront aberration results of accelerated corneal cross-linking (CXL) during a 24-month follow-up.Methods. Forty-seven eyes underwent riboflavin-ultraviolet A-induced accelerated CXL treatment (30 mW/cm2with a total dose of 7.2 joules/cm2). Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), spherical and cylindrical values, keratometry (K) measurements (Ksteep,Kflat,Kavg, andKapex), central corneal thickness, and anterior corneal aberrometric analyses including total wavefront error (WFE), total high order aberration (HOA), astigmatism, trefoil, coma, quadrafoil, secondary astigmatism, and spherical aberration were evaluated.Results. The mean UDVA and CDVA were significantly improved at 1 (p=0.003andp=0.004, resp.) and 2 years after treatment (p=0.001andp=0.001, resp.). The meanKsteep,Kflat,Kaverage, andKapexvalues were significantly lower than baseline at 12 months (p=0.008,p=0.024,p=0.001, andp=0.014, resp.) and 24 months (p=0.014,p=0.017,p=0.001, andp=0.012, resp.). Corneal thickness showed a significant decrease at 1 month. Total HOA and coma decreased significantly at the 12-month (p=0.001andp=0.009, resp.) and 24-month visits (p=0.001andp=0.007, resp.).Conclusion. Accelerated CXL (30 mW/cm2) was found to be effective in improving UDVA, CDVA, corneal topography readings, total HOA, and coma aberrations during the 24-month follow-up.

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Corneal Cross-Linking (with a Partial Deepithelization) in Keratoconus with Five Years of Follow-Up

Ophthalmology and Eye Diseases ◽

10.4137/oed.s38364 ◽

2016 ◽

Vol 8 ◽

pp. OED.S38364 ◽

Cited By ~ 5

Author(s):

Virgilio Galvis ◽

Alejandro Tello ◽

Néstor I. Carreño ◽

Alvaro I. Ortiz ◽

Rodrigo Barrera ◽

...

Keyword(s):

Visual Acuity ◽

Corneal Thickness ◽

Case Series ◽

Cross Linking ◽

Spherical Equivalent ◽

Corneal Endothelial Cells ◽

Corneal Resistance Factor ◽

Endothelial Cell Count ◽

Corrected Visual Acuity

We performed a retrospective interventional case series including 80 eyes of 48 patients with keratoconus (KC) who were treated with modified corneal cross-linking (CXL) for KC (with a partial deepithelization in a pattern of stripes). The average follow-up was 5.8 years (with a minimum of 5 years). At the last follow-up visit, compared with preoperative values, there were no significant changes in spherical equivalent, average keratometry, corneal thickness, corneal hysteresis, or corneal resistance factor. The distance-corrected visual acuity was 20/39 preoperatively and 20/36 postoperatively ( P = 0.3). The endothelial cell count decreased by 4.7% ( P < 0.005). These findings suggest that this modified corneal CXL technique is a safe and effective alternative to halt the progression of KC up to five years after the procedure. However, some concerns remain as to whether this technique can affect in some degree the corneal endothelial cells.

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Detecting subclinical keratoconus by biomechanical analysis in tomographically regular keratoconus fellow eyes

European Journal of Ophthalmology ◽

10.1177/11206721211063740 ◽

2021 ◽

pp. 112067212110637

Author(s):

Victor A Augustin ◽

Hyeck-Soo Son ◽

Isabella Baur ◽

Ling Zhao ◽

Gerd U Auffarth ◽

...

Keyword(s):

Visual Acuity ◽

Central Corneal Thickness ◽

Corneal Thickness ◽

Case Series ◽

Biomechanical Analysis ◽

Corvis St ◽

Corrected Visual Acuity ◽

The Mean ◽

Best Corrected Visual Acuity ◽

Fellow Eyes

Purpose To analyze the tomographically non-affected second eyes of keratoconus patients using the Corvis ST to detect any biomechanical abnormalities or subclinical keratoconus. Methods In this retrospective, single-center, consecutive case series 244 eyes of 122 keratoconus patients were analyzed between November 2020 and February 2021. Fourteen fellow eyes fulfilled the inclusion criteria and showed no clinical or tomographic signs of keratoconus. Main outcome measures included best-corrected visual acuity, tomographic and biomechanical analyses using Scheimpflug imaging: Pentacam and Corvis ST (Oculus, Wetzlar, Germany). Tomographic analyses included anterior and posterior simulated keratometry, K-Max, central corneal thickness, thinnest corneal thickness, Belin/Ambrosio Ectasia Display, and the ABCD grading system. For biomechanical analyses, the corneal biomechanical index (CBI) and tomographic biomechanical index were used. Results The mean best-corrected visual acuity was 0.01 ± 0.10 logMAR. Mean K-Max was 43.79 ± 1.12 D, mean central corneal thickness 529 ± 25 µm, mean thinnest corneal thickness 524 ± 23 µm, and mean Belin/Ambrosio Ectasia Display 1.0 ± 0.32. The mean CBI was 0.30 ± 0.21. Regular CBI values were found in six of 14 patients. The mean tomographic biomechanical index was 0.47 ± 0.22 with regular values observed in only two of 14 patients. No signs of tomographic or biomechanical abnormalities were shown in only one of 14 keratoconus fellow eyes, with regular ABCD, Belin/Ambrosio Ectasia Display, CBI and tomographic biomechanical index values. Conclusions Tomographically normal fellow eyes of keratoconus patients are rare. In these cases, a biomechanical analysis of the cornea may help detect a subclinical keratoconus. The tomographic biomechanical index was the most sensitive index to verify a mild ectasia.

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Effect of phacoemulsification with intraocular lens implantation in eyes with cataract and functioning filtering blebs

Asian Journal of Ophthalmology ◽

10.35119/asjoo.v13i2.44 ◽

2013 ◽

Vol 13 (2) ◽

pp. 33-41

Author(s):

Devendra Maheshwari ◽

Rengappa Ramakrishanan ◽

Mohideen Abdul Kader ◽

Neelam Pawar ◽

Ankit Gupta

Keyword(s):

Visual Acuity ◽

Intraocular Pressure ◽

Intraocular Lens ◽

Intraocular Lens Implantation ◽

Corrected Visual Acuity ◽

Lens Implantation ◽

The Mean ◽

One Year ◽

Best Corrected Visual Acuity

Aim: To evaluate the effect of phacoemulsification with intraocular lens implantation in eyes with pre-existing trabeculectomy.Methods: This prospective single-center clinical study evaluated intraocular pressure in 60 eyes of 60 patients who underwent phacoemulsification and implantation of a foldable intraocular lens after a previous successful trabeculectomy. Patients who had a trabeculectomy more than one year prior to the study were included. Intraocular pressure, number of antiglaucoma medications, bleb appearance, and visual acuity were recorded preoperatively, and at each follow-up examination and 12 months after phacoemulsification.Results: The mean intraocular pressure before phacoemulsification was 12.42 mmHg (SD, 4.60 mmHg), which increased to 14.98 mmHg (SD, 4.18 mmHg), 14.47 mmHg (SD, 3.58 mmHg), 15.44 mmHg (SD, 3.60 mmHg), and 15.71 mmHg (SD, 3.47 mmHg) after one, three, six, and 12 months, respectively. At each follow-up visit, the mean IOP was significantly higher than the preoperative value (p < 0.001, p = 0.015, p ≤ 0.001, and p = 0.001 at month one, three, six, and 12, respectively). The mean preoperative best-corrected visual acuity was 0.98 logMAR (SD, 0.44 logMAR) and the mean postoperative best-corrected visual acuity at 12 months was 0.20 logMAR (SD, 0.21 logMAR) [p = 0.0001]. The mean preoperative number of antiglaucoma medications used was 0.57 (SD, 0.63), which increased to 0.65 (SD, 0.63 ), 0.70 (SD, 0.72 ) 0.68, (SD, 0.70), and 0.67 (SD, 0.77 ) at one, three, six, and 12 months, respectively, but there were no statistically significant differences. Bleb size decreased clinically after phacoemulsification. Nineteen of 60 eyes (32%) developed fibrosis of bleb with decreased bleb size.Conclusion: Phacoemulsification with intraocular lens implantation significantly increased intraocular pressure and increased the number of antiglaucoma medications in eyes with pre-existing functioning filtering blebs.

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The effect of amblyopia on clinical outcomes of children with astigmatism

Therapeutic Advances in Ophthalmology ◽

10.1177/25158414211040898 ◽

2021 ◽

Vol 13 ◽

pp. 251584142110408

Author(s):

Burçin Çakır ◽

Nilgün Özkan Aksoy ◽

Sedat Özmen ◽

Özlem Bursalı

Keyword(s):

Visual Acuity ◽

Clinical Outcomes ◽

Medical Records ◽

Convergence Insufficiency ◽

Corrected Visual Acuity ◽

Ocular Deviation ◽

The Mean ◽

The Difference ◽

Best Corrected Visual Acuity

Background: Amblyopia is more common in children with high astigmatism, but factors contributing to development of amblyopia and visual outcomes are not fully understood. Objective: To evaluate the effect of amblyopia on the clinical outcomes in children with ⩾1.75 diopter (D) astigmatism. Methods: We reviewed the medical records of children with ⩾1.75 D astigmatism with and without amblyopia (amblyopes group and non-amblyopes group). The mean age, gender, amount and type of ocular deviation, presence of convergence insufficiency (CI), stereopsis, time of initial spectacle use and follow-up time, differences in best-corrected visual acuity (VoD) and spherical equivalent (SE) between eyes were assessed and compared between the groups. Best-corrected visual acuity (BCVA), mean SE, astigmatism measurements were assessed and compared between amblyopic, fellow, and non-amblyopic eyes. Results: The records included 68 eyes of 34 children with amblyopia and 56 eyes of 28 children without amblyopia. The mean age, gender, amount and type of ocular deviation, presence of CI, stereopsis, time of initial spectacle use, follow-up time, and the difference in SE did not differ between groups. In amblyopes, exodeviation was more common and statistically greater in near (33 cm) than at distance (6 m) (p = 0.005). The mean BCVA and astigmatism values were statistically different between amblyopic, fellow, and non-amblyopic eyes. Conclusion: A greater near than distance exodeviation and higher mean astigmatism value were found in amblyopic children with astigmatism.

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Clinical Outcomes of Small Incision Lenticule Extraction with Accelerated Cross-Linking (ReLEx SMILE Xtra) in Patients with Thin Corneas and Borderline Topography

Journal of Ophthalmology ◽

10.1155/2015/263412 ◽

2015 ◽

Vol 2015 ◽

pp. 1-7 ◽

Cited By ~ 17

Author(s):

Sri Ganesh ◽

Sheetal Brar

Keyword(s):

Visual Acuity ◽

Clinical Outcomes ◽

Corneal Thickness ◽

Cross Linking ◽

Small Incision Lenticule Extraction ◽

Uncorrected Visual Acuity ◽

Distant Visual Acuity ◽

Lenticule Extraction ◽

The Mean

Purpose. To study the safety and clinical outcomes of ReLEx SMILE with accelerated cross-linking in individuals with thinner corneas, borderline topography, and higher refractive errors.Methods. Eligible patients first underwent SMILE procedure for correction of myopic refractive error. Following the removal of lenticule, 0.25% riboflavin in saline was injected into the interface and allowed to diffuse for 60 seconds. Finally, eye was exposed to UV-A radiation of 45 mW/cm2for 75 seconds through the cap. Total energy delivered was 3.4 J/cm2.Results. 40 eyes of 20 patients with mean age of 26.75 ± 5.99 years were treated. Mean follow-up was 12 months ± 28.12 days. Mean spherical equivalent (SE) was −5.02 ± 2.06 D preoperatively and −0.24 ± 0.18 D postoperatively. The mean central corneal thickness (CCT) and keratometry changed from 501 ± 25.90 µm to 415 ± 42.26 µm and 45.40 ± 1.40 D to 41.2 ± 2.75 D, respectively. Mean uncorrected visual acuity (UCVA) was 20/25 or better in all eyes. No eyes lost lines of corrected distant visual acuity (CDVA). There were no complications like haze, keratitis, ectasia, or regression.Conclusion. Based on the initial clinical outcome it appears that SMILE Xtra may be a safe and feasible modality to prevent corneal ectasia in susceptible individuals.

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Long-term visual, anterior and posterior corneal changes after crosslinking for progressive keratoconus

European Journal of Ophthalmology ◽

10.1177/11206721211052878 ◽

2021 ◽

pp. 112067212110528

Author(s):

Abdelrahman Salman ◽

Ali Ali ◽

Shaaban Rafea ◽

Rana Omran ◽

Buraa Kubaisi ◽

...

Keyword(s):

Visual Acuity ◽

Statistical Significance ◽

Corneal Thickness ◽

Cross Linking ◽

Long Term Outcomes ◽

Corrected Distance Visual Acuity ◽

Hyperopic Shift ◽

The Mean

Aim To evaluate the long-term outcomes of corneal cross-linking (CXL) in patients with progressive keratoconus. Method In this retrospective non-comparative study, forty-five eyes of 31 patients with progressive keratoconus were treated with 30 min “epi-off” corneal cross-linking. The visual, refractive, topographic and tomographic outcomes were evaluated preoperatively and at least 10 years after cross-linking. Results Ten years post-corneal cross-linking, the mean anterior maximum keratometry decreased (−2.10 ± 3.25 D, P = 0.0001). Conversely, the posterior maximum keratometry increased (6.38 ± 9.79 D, P = 0.065). Both uncorrected and corrected distance visual acuity improved (LogMAR −0.08 ± 0.30) and (LogMAR −0.05 ± 0.21), respectively (P > 0.05, both). A statistically significant hyperopic shift was observed postoperatively (0.70 ± 1.31 D, P = 0.0009). The anterior topographic cylinder values revealed no change (−0.17 ± 1.31 D, P = 0.3), whereas the mean posterior cylinder values decreased (absolute value increased) significantly compared to baseline from −1.31 ± 0.97 D to −1.82 ± 1.78 D, (P < 0.05). The minimum corneal thickness values decreased significantly (−35.11 ± 48.63 µm, P = 0.0001). Four eyes (8.8%) showed more than 1 D increase in the anterior maximum keratometry. Conclusion This protocol and duration of Epi-off corneal cross-linking was found to be effective in halting keratoconus progression over the follow up period (10 years). Anterior corneal flattening and a hyperopic shift were observed. A statistically significant increase in the posterior corneal cylinder was observed. Although, not reaching statistical significance, the logMAR uncorrected and corrected visual acuity were improved.

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