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Deshmukh R, Ong ZZ, Rampat R, Alió del Barrio JL, Barua A, Ang M, Mehta JS, Said DG, Dua HS, Ambrósio R, Ting DSJ. Management of keratoconus: an updated review. Front Med (Lausanne) 2023; 10:1212314. [PMID: 37409272 PMCID: PMC10318194 DOI: 10.3389/fmed.2023.1212314] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 05/30/2023] [Indexed: 07/07/2023] Open
Abstract
Keratoconus is the most common corneal ectatic disorder. It is characterized by progressive corneal thinning with resultant irregular astigmatism and myopia. Its prevalence has been estimated at 1:375 to 1:2,000 people globally, with a considerably higher rate in the younger populations. Over the past two decades, there was a paradigm shift in the management of keratoconus. The treatment has expanded significantly from conservative management (e.g., spectacles and contact lenses wear) and penetrating keratoplasty to many other therapeutic and refractive modalities, including corneal cross-linking (with various protocols/techniques), combined CXL-keratorefractive surgeries, intracorneal ring segments, anterior lamellar keratoplasty, and more recently, Bowman's layer transplantation, stromal keratophakia, and stromal regeneration. Several recent large genome-wide association studies (GWAS) have identified important genetic mutations relevant to keratoconus, facilitating the development of potential gene therapy targeting keratoconus and halting the disease progression. In addition, attempts have been made to leverage the power of artificial intelligence-assisted algorithms in enabling earlier detection and progression prediction in keratoconus. In this review, we provide a comprehensive overview of the current and emerging treatment of keratoconus and propose a treatment algorithm for systematically guiding the management of this common clinical entity.
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Affiliation(s)
- Rashmi Deshmukh
- Department of Cornea and Refractive Surgery, LV Prasad Eye Institute, Hyderabad, India
| | - Zun Zheng Ong
- Department of Ophthalmology, Queen’s Medical Centre, Nottingham, United Kingdom
| | - Radhika Rampat
- Department of Ophthalmology, Royal Free London NHS Foundation Trust, London, United Kingdom
| | - Jorge L. Alió del Barrio
- Cornea, Cataract and Refractive Surgery Unit, Vissum (Miranza Group), Alicante, Spain
- Division of Ophthalmology, School of Medicine, Universidad Miguel Hernández, Alicante, Spain
| | - Ankur Barua
- Birmingham and Midland Eye Centre, Birmingham, United Kingdom
| | - Marcus Ang
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
| | - Jodhbir S. Mehta
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
| | - Dalia G. Said
- Department of Ophthalmology, Queen’s Medical Centre, Nottingham, United Kingdom
- Academic Ophthalmology, School of Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Harminder S. Dua
- Department of Ophthalmology, Queen’s Medical Centre, Nottingham, United Kingdom
- Academic Ophthalmology, School of Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Renato Ambrósio
- Department of Cornea and Refractive Surgery, Instituto de Olhos Renato Ambrósio, Rio de Janeiro, Brazil
- Department of Ophthalmology, Federal University of the State of Rio de Janeiro (UNIRIO), Rio de Janeiro, Brazil
- Federal University of São Paulo (UNIFESP), São Paulo, Brazil
| | - Darren Shu Jeng Ting
- Birmingham and Midland Eye Centre, Birmingham, United Kingdom
- Academic Ophthalmology, School of Medicine, University of Nottingham, Nottingham, United Kingdom
- Academic Unit of Ophthalmology, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
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Al-Qahtani BS, Al-Swailem SA, Ahmad K, Khandekar R. Vision related quality of life of patients with keratoconus after keratoplasty at a Tertiary Eye Hospital in Saudi Arabia. Eur J Ophthalmol 2021; 31:3500-3504. [PMID: 34053313 DOI: 10.1177/11206721211020648] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
PURPOSE To assess the vision-related quality of life (VQoL) for patients with advanced keratoconus (KC) after primary keratoplasty. METHODS This was a cross-sectional study, undertaken at the King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia, in December 2015. Adults (aged 22-75 years) were interviewed via telephone with regard to their VQoL, on the average, 5 years after undergoing primary keratoplasty for advanced KC. VQoL was measured using the Visual Functioning Index (VF-14, Arabic version). The relationship between VQoL and different demographic and clinical factors was evaluated using linear regression. RESULTS Ninety-five adults participated in the study (54.7 % males; mean age at the interview = 32.05 ± 7.18 years). Eighty-seven (91.6%) of them had undergone PKP. The overall mean VF-14 score was 86.19% (SD: 12.91). VF-14 score was significantly lower for individuals with higher log average K (beta coefficient, -28.32; 95% confidence interval [CI], -55.59 to -1.04; p = 0.042) and hazy graft (beta coefficient, -12.76; 95% CI, -21.16 to -4.36; p = 0.003) adjusting for the effect of keratoplasty technique and BCVA in the better eye at the last follow up. CONCLUSION This study suggests that most patients with advanced keratoconus had satisfactory VQoL after primary keratoplasty. Certain subgroups may benefit less substantially than others and would need a particular attention.
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Affiliation(s)
- Bader S Al-Qahtani
- Research Department, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia.,Cornea, Anterior Segment and Refractive Surgery Department, University of Ottawa Eye Institute, Ottawa, Ontario, Canada.,Ophthalmology Department, King Faisal Specialist Hospital & Research Center, Riyadh, Saudi Arabia
| | - Samar A Al-Swailem
- Research Department, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
| | - Khabir Ahmad
- Research Department, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
| | - Rajiv Khandekar
- Research Department, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
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Ormonde S. Refractive surgery for keratoconus. Clin Exp Optom 2021; 96:173-82. [DOI: 10.1111/cxo.12051] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Revised: 01/31/2013] [Accepted: 02/03/2013] [Indexed: 11/28/2022] Open
Affiliation(s)
- Sue Ormonde
- Department of Ophthalmology, University of Auckland, Auckland, New Zealand,
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Jacobs DS, Carrasquillo KG, Cottrell PD, Fernández-Velázquez FJ, Gil-Cazorla R, Jalbert I, Pucker AD, Riccobono K, Robertson DM, Szczotka-Flynn L, Speedwell L, Stapleton F. CLEAR - Medical use of contact lenses. Cont Lens Anterior Eye 2021; 44:289-329. [PMID: 33775381 DOI: 10.1016/j.clae.2021.02.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 02/01/2021] [Indexed: 12/11/2022]
Abstract
The medical use of contact lenses is a solution for many complex ocular conditions, including high refractive error, irregular astigmatism, primary and secondary corneal ectasia, disfiguring disease, and ocular surface disease. The development of highly oxygen permeable soft and rigid materials has extended the suitability of contact lenses for such applications. There is consistent evidence that bandage soft contact lenses, particularly silicone hydrogel lenses, improve epithelial healing and reduce pain in persistent epithelial defects, after trauma or surgery, and in corneal dystrophies. Drug delivery applications of contact lens hold promise for improving topical therapy. Modern scleral lens practice has achieved great success for both visual rehabilitation and therapeutic applications, including those requiring retention of a tear reservoir or protection from an adverse environment. This report offers a practical and relevant summary of the current evidence for the medical use of contact lenses for all eye care professionals including optometrists, ophthalmologists, opticians, and orthoptists. Topics covered include indications for use in both acute and chronic conditions, lens selection, patient selection, wear and care regimens, and recommended aftercare schedules. Prevention, presentation, and management of complications of medical use are reviewed.
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Affiliation(s)
- Deborah S Jacobs
- Massachusetts Eye & Ear, Cornea and Refractive Surgery Service, Harvard Medical School, Boston, MA, USA.
| | | | | | | | | | | | | | | | | | - Loretta Szczotka-Flynn
- Department of Ophthalmology & Visual Science, Case Western Reserve University, Cleveland, OH, USA
| | - Lynne Speedwell
- Great Ormond Street Hospital for Children NHS Trust, Moorfields Eye Hospital, London, UK
| | - Fiona Stapleton
- School of Optometry and Vision Science, UNSW Sydney, Australia
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Shetty R, Israni NA, Ramuka S, Dadachanji Z, Roy AS, Mehra R, Lalgudi VG. Intracorneal Ring Segments Followed by Simultaneous Topography-Guided Removal of Epithelium and Stroma With Accelerated Collagen Cross-Linking For Keratoconus (I-TRESK/CXL). Asia Pac J Ophthalmol (Phila) 2020; 10:152-160. [PMID: 33369925 DOI: 10.1097/apo.0000000000000342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
PURPOSE The aim of this study was to assess the visual, topographic, and aberrometric outcomes of a novel tissue sparing technique, topography-guided removal of epithelium, and stroma in keratoconus (TRESK) along with accelerated collagen cross-linking (CXL), 1 month after Intacs insertion. DESIGN Prospective interventional study. METHODS Fourty-eight eyes (45 patients) with keratoconus underwent femto-assisted Intacs insertion. After 1 month, TRESK and CXL (9 mW/cm2 for 10 minutes) was done. TRESK is a decentered trans-PTK (phototherapeutic keratectomy) with center and area of ablation at the location of the steepest tangential anterior curvature and area of the cone respectively. Total ablation (epithelium plus stroma) was limited to 75 μm. Postoperative measurements were performed 1 month after Intacs, 6 weeks after Intacs followed by TRESK/CXL, and at the final visit 12 months after Intacs followed by TRESK/CXL. RESULTS For all eyes studied, uncorrected distance visual acuity and corrected distance visual acuity (CDVA) (logMAR) improved from preoperative means of 1.05 ± 0.05 and 0.31 ± 0.03 logMAR to postoperative means of 0.52 ± 0.05 (P < 0.001) and 0.20 ± 0.02 logMAR (P = 0.009), respectively. The mean preoperative sphere, cylinder and mean refractive spherical equivalent decreased from -4.52 ± 0.98 D, -4.81 ± 0.25 D, -6.93 ± 0.99 D to -0.77 ± 0.53 D (P = 0.029), -3.13 ± 0.24 D (P = 0.002), and -2.34 ± 0.53 D (P = 0.021), respectively with a mean keratometric flattening of 5.06D (P < .0001) at the final visit. In total, 2.08% of the eyes lost 1 Snellen line of CDVA. Sixty eight percent and 27% of the eyes gained 2 Snellen lines or more of uncorrected distance visual acuity and CDVA, respectively. CONCLUSIONS Simultaneous TRESK with CXL done 1 month after Intacs insertion (I-TRESK) in keratoconus eyes provided significant visual gain with refractive and topographic improvement. This novel procedure involving customized PTK before CXL is safe, easy to plan and perform, and provides good outcomes.
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Affiliation(s)
- Rohit Shetty
- Department of Cornea and Refractive surgery, Narayana Nethralaya, Bangalore, India
| | - Neeraj Ashok Israni
- Department of Cornea and Refractive surgery, Narayana Nethralaya, Bangalore, India
| | - Saurabh Ramuka
- Department of Cornea and Refractive surgery, Narayana Nethralaya, Bangalore, India
| | - Zelda Dadachanji
- Department of Cornea and Refractive surgery, Narayana Nethralaya, Bangalore, India
| | - Abhijit Sinha Roy
- Imaging, Biomechanics and mathematical modelling solutions lab, Narayana Nethralaya foundation, Bangalore, India
| | - Rohan Mehra
- Department of Cornea and Refractive surgery, Narayana Nethralaya, Bangalore, India
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7
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Rocha G, Silva LNP, Chaves LFOB, Bertino P, Torquetti L, de Sousa LB. Intracorneal Ring Segments Implantation Outcomes Using Two Different Manufacturers' Nomograms for Keratoconus Surgery. J Refract Surg 2020; 35:673-683. [PMID: 31610009 DOI: 10.3928/1081597x-20190916-01] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Accepted: 09/16/2019] [Indexed: 11/20/2022]
Abstract
PURPOSE To compare the outcomes of intracorneal ring segments (ICRS) implantation in keratoconic eyes with a similar tomographic pattern, using two different manufacturers' nomograms for surgical planning. METHODS ICRS were implanted alternately in patients with the same tomographic pattern of keratoconus divided into two groups according to the surgical planning proposed by the ICRS manufacturers (Keraring, Mediphacos, Belo Horizonte, Brazil, and Ferrara Ring, AJL Ophthalmics, Vitoria, Spain). Visual, refractive, keratometric, corneal aberrometry, and optical quality changes were evaluated during a 6-month follow-up. Corneal and manifest refractive astigmatic changes were also analyzed using the double-angle polar plot and the Alpins vectorial method through the following components: target induced astigmatism, surgically induced astigmatism, difference vector, correction index, angle of error, index of success, flattening effect, and torque. RESULTS After ICRS implantation, both groups showed significant improvement (P < .05) in visual and keratometric data. Corneal aberrometric changes and optical quality improvement were also statistically significant in both groups, except for trefoil (P > .05 in all intervals). The Alpins method analysis showed a better performance in the Keraring group, but with no statistically significant difference between groups (P > .05). Comparison between groups showed a statistically significant difference only in tomographic astigmatism in double-angle polar plot analysis (P = .03), with more significant improvement in the Keraring group. CONCLUSIONS Both manufacturers' nomograms resulted in statistically significant improvement in most of the parameters analyzed, with greater correction of corneal tomographic astigmatism in the group operated on according to the spherical equivalent/tomographic astigmatism nomogram. [J Refract Surg. 2019;35(10):673-683.].
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Sakellaris D, Balidis M, Gorou O, Szentmary N, Alexoudis A, Grieshaber MC, Sagri D, Scholl H, Gatzioufas Z. Intracorneal Ring Segment Implantation in the Management of Keratoconus: An Evidence-Based Approach. Ophthalmol Ther 2019; 8:5-14. [PMID: 31605316 PMCID: PMC6789055 DOI: 10.1007/s40123-019-00211-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Indexed: 01/19/2023] Open
Abstract
Intracorneal ring segment (ICRS) implantation represents a modern, minimally invasive, surgical option for visual improvement in patients with keratoconus. ICRS modify the corneal geometry in a manner that enhances its refractive properties and thereby, they improve visual acuity. It is well-documented that implantation of ICRS decreases the keratometric readings, spherical equivalent and cylinder, reduces high-order aberrations and improves uncorrected distance visual acuity (UDVA) and best-corrected distance visual acuity (BCDVA) in patients with keratoconus. Success rate after ICRS implantation is high, depending on appropriate patient selection and adherence to suitable implantation nomograms, and most important, the overall complication rate is very low. This review is summarizing current indications/contra-indications for ICRS implantation, implantation techniques, clinical outcomes and potential complications, shedding light on myths and realities related to this innovative surgical option.
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Affiliation(s)
| | | | - Olga Gorou
- Ophthalmica Institute, Thessaloniki, Greece
| | - Nora Szentmary
- Department of Ophthalmology, University Clinic Saarland, Homburg, Saarland, Germany
- Department of Ophthalmology, Semmelweis University, Budapest, Hungary
| | - Antonios Alexoudis
- Department of Ophthalmology, University Hospital Basel, Basel, Switzerland
| | | | | | - Hendrik Scholl
- Department of Ophthalmology, University Hospital Basel, Basel, Switzerland
| | - Zisis Gatzioufas
- Department of Ophthalmology, University Hospital Basel, Basel, Switzerland.
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9
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Monteiro T, Alfonso JF, Freitas R, Franqueira N, Faria-Correira F, Ambrósio R, Madrid-Costa D. Comparison of Complication Rates between Manual and Femtosecond Laser-Assisted Techniques for Intrastromal Corneal Ring Segments Implantation in Keratoconus. Curr Eye Res 2019; 44:1291-1298. [PMID: 31226888 DOI: 10.1080/02713683.2019.1635165] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Purpose: To compare the incidence of complications between manual and femtosecond-laser assisted surgery for intrastromal corneal ring segments (ICRS) implantation.Material and methods: This study included keratoconus patients who had ICRS implantation using manual dissection and using the femtosecond laser with a minimum follow-up of 12 months. Uncorrected (UDVA) corrected (CDVA) distance visual acuity (CDVA), refraction, corneal topography and aberrometry, pachymetry map and slit-lamp microscopy were assessed before and after surgery.Results: The study included 265 eyes in the manual group and 111 in the femtosecond laser group. In the manual group, there were complications in 48 eyes (18.11%); while in the femtosecond laser 4 eyes had a complication (3.6%). In the manual group, the most frequent complications were ICRS exchange/adjustment for visual and refractive enhancement (25 eyes; 9.43%) and late ICRS spontaneous extrusion (15 eyes; 5.66%). In the manual group, 81.25% of complications were observed during the first 3 years of surgeon's experience. Eyes who suffered a complication had preoperatively higher mean refractive (p = .002) and topographic cylinder (p = .003) and lower UDVA (p = .005) and CDVA (p = .002). After a second surgical procedure for complication management visual, refractive and topographic outcomes significantly improved.Conclusion: Manual mechanical ICRS surgery shows a higher rate of intra- and postoperative mechanical and refractive complications when compared to femtosecond laser assisted technique. The incidence is specially higher during the surgeon's first years of implementation of the technique.
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Affiliation(s)
- Tiago Monteiro
- Ophthalmology Department, Hospital de Braga, Braga, Portugal.,Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal
| | - José F Alfonso
- Instituto Universitario Fernández-Vega, Fundación de Investigación Oftalmológica, Universidad de Oviedo, Oviedo, Spain
| | - Rui Freitas
- Ophthalmology Department, Hospital de Braga, Braga, Portugal.,Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal
| | - Nuno Franqueira
- Ophthalmology Department, Hospital de Braga, Braga, Portugal.,Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal
| | - Fernando Faria-Correira
- Ophthalmology Department, Hospital de Braga, Braga, Portugal.,Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal
| | - Renato Ambrósio
- Rio de Janeiro Corneal Tomography and Biomechanics Study Group, Rio de Janeiro, Brazil.,Department of Ophthalmology, Federal University of São Paulo, São Paulo, Brazil
| | - David Madrid-Costa
- Optometry and Vision Department, Faculty of Optics and Optometry, Universidad Complutense de Madrid, Madrid, Spain
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Nguyen N, Gelles JD, Greenstein SA, Hersh PS. Incidence and associations of intracorneal ring segment explantation. J Cataract Refract Surg 2019; 45:153-158. [DOI: 10.1016/j.jcrs.2018.09.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 09/07/2018] [Accepted: 09/24/2018] [Indexed: 10/27/2022]
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Résultats réfractifs et facteurs pronostiques de succès du traitement du kératocône par anneaux intracornéens : étude rétrospective sur 75 yeux. J Fr Ophtalmol 2019; 42:118-126. [DOI: 10.1016/j.jfo.2018.09.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 09/03/2018] [Indexed: 11/15/2022]
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Mukhtar S, Ambati BK. Pediatric keratoconus: a review of the literature. Int Ophthalmol 2018; 38:2257-2266. [PMID: 28852910 PMCID: PMC5856649 DOI: 10.1007/s10792-017-0699-8] [Citation(s) in RCA: 102] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 08/18/2017] [Indexed: 10/19/2022]
Abstract
PURPOSE To describe the epidemiology and prevalence, rates of progression, difference between adult and pediatric populations, and therapeutic approaches to pediatric keratoconus from documented literature. METHODS A literature search was done on PubMed using key words including pediatric keratoconus, children with keratoconus, adult keratoconus, penetrating keratoplasty, corneal cross-linking and intracorneal ring segments. The literature was reviewed and reported to explore the key epidemiological differences between the pediatric and adult population with regards to presentation and treatment options. RESULTS Pediatric keratoconus is more aggressive than adult keratoconus, which has been explained by structural differences in the cornea between both populations. High rates of progression were documented in pediatric populations. While corneal collagen cross-linking, intracorneal ring segments and penetrating keratoplasties have been used as therapies in the pediatric population, the literature overwhelmingly shows higher rates of failure and progression despite these measures as compared to adults. CONCLUSION Pediatric keratoconus is more aggressive than adult keratoconus, and current therapies used in adults may not be sufficient for the pediatric population.
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Affiliation(s)
- Sabrina Mukhtar
- School of Medicine, Virginia Commonwealth University, 1201 E. Marshall St., 4th Floor, Richmond, VA, 232983, USA.
| | - Balamurali K Ambati
- Moran Eye Center, University of Utah, 64 Mario Capecchi Dr, Salt Lake City, UT, 84132, USA
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Alzahrani K, Cristian C, Harper S, Carley F, Brahma A, Morley D, Hillarby MC. Corneal imaging and densitometry measurements in keratoconus patients to monitor disease progression and treatment outcomes after contact lens or Intacs treatment. Clin Ophthalmol 2018; 12:1653-1658. [PMID: 30233127 PMCID: PMC6130308 DOI: 10.2147/opth.s168865] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Aim The aim of this study was to compare the pre- and posttreatment corneal densitometry and corneal thickness value of keratoconus (KCN) patients managed via contact lenses (CLs) or by both intrastromal corneal rings and contact lenses. Patients and methods This prospective study was performed at the Manchester Royal Eye Hospital, UK. Patients were recruited before treatment and followed up for 12 months. Data of corneal densitometry and corneal thickness were collected using the Oculus Pentacam at the pretreatment visit and posttreatment visit at 12 months. Results Corneal clarity significantly differs between both groups at pre treatment at zone 0-2 mm for the anterior layer (P=0.002). The same diversity is present at zone 2-6 mm for the anterior layer (P=0.003) and posterior layer (P=0.008). The corneal clarity diversity found was not statistically significant at 12 months post treatment (P>0.05). Corneal thickness was found to be statistically significantly different between pre treatment and post treatment for the CL group for central corneal thickness (CCT) and thinnest area (P=0.01 and P=0.02), respectively. Discussion This study shows that KCN management with Intacs was found to be effective in maintaining corneal clarity for a longer time than that with CL alone. On the other hand, corneal clarity reduces with disease progression in cases managed with CLs only. Analysis of Oculus Pentacam images provides an objective evaluation to monitor the corneal status after these different pathways of management.
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Affiliation(s)
- Khaled Alzahrani
- Division of Pharmacy and Optometry, School of Health Sciences, University of Manchester, Manchester, UK, .,Ophthalmology Department, King Fahad Armed Forces Hospital, Jeddah, Saudi Arabia,
| | | | | | | | - Arun Brahma
- Manchester Royal Eye Hospital, Manchester, UK
| | | | - M Chantal Hillarby
- Division of Pharmacy and Optometry, School of Health Sciences, University of Manchester, Manchester, UK,
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Comparison of Intrastromal Corneal Ring Segment Implantation only and in Combination with Collagen Crosslinking for Keratoconus. Eur J Ophthalmol 2018; 23:629-34. [DOI: 10.5301/ejo.5000250] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/19/2012] [Indexed: 11/20/2022]
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Titiyal JS, Chawla B, Sharma N. Deep Anterior Lamellar Keratoplasty with Intacs Explantation in Keratoconus. Eur J Ophthalmol 2018; 20:874-8. [DOI: 10.1177/112067211002000510] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Jeewan S. Titiyal
- Cornea and Refractive Surgery Services, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi - India
| | - Bhavna Chawla
- Cornea and Refractive Surgery Services, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi - India
| | - Namrata Sharma
- Cornea and Refractive Surgery Services, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi - India
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Hashemian SJ, Farshchian N, Foroutam-Jazi A, Jafari ME, Hashemian MS, Hashemian SM. Visual and Refractive Outcomes and Tomographic Changes after Femtosecond Laser-assisted Intrastromal Corneal Ring Segment Implantation in Patients with Keratoconus. J Ophthalmic Vis Res 2018; 13:376-382. [PMID: 30479705 PMCID: PMC6210881 DOI: 10.4103/jovr.jovr_42_17] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Purpose: To evaluate the visual, refractive, and tomography changes after femtosecond laser-assisted intrastromal corneal ring segment (ICRS; Intacs® SK) implantation in patients with keratoconus. Methods: In this prospective interventional case series, Intacs SK ICRSs were inserted using a femtosecond laser into eyes with stage I–IV keratoconus. Visual, refractive, and corneal tomography changes, along with surgical complications, were analyzed 1 week, 2 months, and 6 months postoperatively. Results: The study evaluated 71 eyes of 52 patients (mean age: 27.5 years). Six months postoperatively, the spherical equivalent, mean sphere, and mean cylinder were decreased by 2.07, 1.47, and 1.13 diopters (D), respectively. The mean preoperative uncorrected distance visual acuity (UDVA) increased from 0.87 ± 0.26 to 0.46 ± 0.19 LogMAR and the mean preoperative corrected distance visual acuity (CDVA) increased from 0.55 ± 0.21 to 0.28 ± 0.17 LogMAR (P < 0.001). Flat and steep keratometry decreased by a mean corneal power in the 3-mm zone, and mean anterior elevation decreased by 0.91 D, 2.52 D, and 1.03 microns (P < 0.001), respectively. Among all eyes, 93.0% gained one or more lines of CDVA. Mean internal anterior chamber depth decreased from 3.25 ± 0.33 to 3.14 ± 0.45 mm (P = 0.001), and mean irregularity in the 3-mm zone decreased from 5.63 ± 1.71 to 5.24 ± 1.82 (P = 0.006). However, mean posterior elevation and irregularity in the 5-mm zone did not change significantly. Conclusion: Implantation of one or two Intacs SK segments is safe and effective to treat keratoconus, leading to significant improvement in UDVA, CDVA, and refractive error.
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Affiliation(s)
- Seyed Javad Hashemian
- Eye Research Center, Rassoul Akram Hospital, Iran University of Medical Sciences, Tehran, Iran
| | - Nooshin Farshchian
- Eye Research Center, Rassoul Akram Hospital, Iran University of Medical Sciences, Tehran, Iran
| | - Alireza Foroutam-Jazi
- Eye Research Center, Rassoul Akram Hospital, Iran University of Medical Sciences, Tehran, Iran
| | | | - Mahsa Sadat Hashemian
- School of Pharmacy, International Campus, Tehran University of Medical Sciences, Tehran, Iran
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Adjustment of Intrastromal Corneal Ring Segments After Unsuccessful Implantation in Keratoconic Eyes. Cornea 2017; 37:182-188. [DOI: 10.1097/ico.0000000000001449] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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19
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Outcome of Keratoconus Management: Review of the Past 20 Years' Contemporary Treatment Modalities. Eye Contact Lens 2017; 43:141-154. [DOI: 10.1097/icl.0000000000000270] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Keraring implantation using the Zeiss Visumax femtosecond laser in the management of patients with keratoconus. Eye (Lond) 2017; 31:916-923. [PMID: 28234352 DOI: 10.1038/eye.2017.13] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2016] [Accepted: 12/01/2016] [Indexed: 11/08/2022] Open
Abstract
PurposeTo evaluate the safety and efficacy of implanted Kerarings in patients with mild, moderate, and severe keratoconus.Patients and methodsA 12-month retrospective case series of 70 eyes of 70 patients who underwent Keraring implantation with the Zeiss Visumax femtosecond laser. Patients were stratified into three groups according to their topography as mild (mean K <48 D) moderate (48-55 D) or severe (>55 D). Main outcome measures were visual acuity, manifest refraction, and corneal topography. Complications were recorded.ResultsA total of 66 patients completed the 12-month follow-up. In all, 4 rings were explanted, 3 due to no improvement in visual function and 1 due to corneal neovascularization. Also, 4 rings were repositioned. In mild disease (n=28), BCVA increased to 0.10 logMAR, sphere decreased to -1.54 D, cylinder decreased to 2.54 D, Kmax decreased to 46.25 D, and keratometric astigmatism to 3.88 D (P<0.01 for each compared with preoperative values). No patients lost vision. In moderate disease (n=27), sphere decreased to -4.06 D, cylinder decreased to 3.47 D, Kmax decreased to 51.69 D, and keratometric astigmatism to 4.56 D (P<0.05 for each compared with preoperative values). In severe disease (n=11), BCVA increased to 0.34 logMAR, Kmax decreased to 57.65 D, and keratometric astigmatism to 5.07 D (P<0.05 for each compared with preoperative values).ConclusionFemtosecond laser-assisted Keraring implantation is a safe and minimally invasive treatment option to improve the refraction and visual function in patients with keratoconus. Patients with mild keratoconus are more likely to have a favourable outcome following Keraring implantation.
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Affiliation(s)
- Davin Johnson
- Department of Ophthalmology, CHUM-Notre Dame Hospital, Montreal, Canada
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Giacomin NT, Mello GR, Medeiros CS, Kiliç A, Serpe CC, Almeida HG, Kara-Junior N, Santhiago MR. Intracorneal Ring Segments Implantation for Corneal Ectasia. J Refract Surg 2016; 32:829-839. [DOI: 10.3928/1081597x-20160822-01] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 07/05/2016] [Indexed: 12/20/2022]
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Hydrogel ocular sealant for wound closure during intrastromal corneal ring segment implantation. J Cataract Refract Surg 2016; 42:515-9. [DOI: 10.1016/j.jcrs.2016.03.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2015] [Revised: 02/24/2016] [Accepted: 03/06/2016] [Indexed: 11/21/2022]
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Barar J, Aghanejad A, Fathi M, Omidi Y. Advanced drug delivery and targeting technologies for the ocular diseases. BIOIMPACTS : BI 2016; 6:49-67. [PMID: 27340624 PMCID: PMC4916551 DOI: 10.15171/bi.2016.07] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2015] [Revised: 02/13/2016] [Accepted: 03/18/2016] [Indexed: 02/06/2023]
Abstract
INTRODUCTION Ocular targeted therapy has enormously been advanced by implementation of new methods of drug delivery and targeting using implantable drug delivery systems (DDSs) or devices (DDDs), stimuli-responsive advanced biomaterials, multimodal nanomedicines, cell therapy modalities and medical bioMEMs. These technologies tackle several ocular diseases such as inflammation-based diseases (e.g., scleritis, keratitis, uveitis, iritis, conjunctivitis, chorioretinitis, choroiditis, retinitis, retinochoroiditis), ocular hypertension and neuropathy, age-related macular degeneration and mucopolysaccharidosis (MPS) due to accumulation of glycosaminoglycans (GAGs). Such therapies appear to provide ultimate treatments, even though much more effective, yet biocompatible, noninvasive therapies are needed to control some disabling ocular diseases/disorders. METHODS In the current study, we have reviewed and discussed recent advancements on ocular targeted therapies. RESULTS On the ground that the pharmacokinetic and pharmacodynamic analyses of ophthalmic drugs need special techniques, most of ocular DDSs/devices developments have been designed to localized therapy within the eye. Application of advanced DDSs such as Subconjunctival insert/implants (e.g., latanoprost implant, Gamunex-C), episcleral implant (e.g., LX201), cationic emulsions (e.g., Cationorm™, Vekacia™, Cyclokat™), intac/punctal plug DDSs (latanoprost punctal plug delivery system, L-PPDS), and intravitreal implants (I-vitaion™, NT-501, NT- 503, MicroPump, Thethadur, IB-20089 Verisome™, Cortiject, DE-102, Retisert™, Iluvein™ and Ozurdex™) have significantly improved the treatment of ocular diseases. However, most of these DDSs/devices are applied invasively and even need surgical procedures. Of these, use of de novo technologies such as advanced stimuli-responsive nanomaterials, multimodal nanosystems (NSs)/nanoconjugates (NCs), biomacromolecualr scaffolds, and bioengineered cell therapies need to be further advanced to get better compliance and higher clinical impacts. CONCLUSION Despite mankind successful battle on ocular diseases, our challenge will continue to battle the ocular disease that happen with aging. Yet, we need to understand the molecular aspects of eye diseases in a holistic way and develop ultimate treatment protocols preferably as non-invasive systems.
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Affiliation(s)
| | | | | | - Yadollah Omidi
- Research Centre for Pharmaceutical Nanotechnology, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
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Depth evaluation of intended vs actual intacs intrastromal ring segments using optical coherence tomography. Eye (Lond) 2015; 30:102-10. [PMID: 26493037 DOI: 10.1038/eye.2015.202] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 08/24/2015] [Indexed: 11/08/2022] Open
Abstract
PurposeEvaluation of actual vs intended intrastromal corneal ring segments (ICRS) implantation depth as measured by anterior segment optical coherence tomography (OCT)MethodsProspective study evaluating 30 Intacs segments implanted manually in 19 eyes of 15 patients suffering from keratoconus. Segment depth evaluation was performed using anterior segment OCT. Measurements were performed above and below the segment at 3 points in relation to the incision site. Statistical analysis was performed using the SAS software for ANOVA, matched t-test, and GLIMMIX procedure.ResultsIntacs segment depth was 153-μm shallower than intended (58% vs 80%). Segment layout demonstrated the proximal and distal portions to be 13-μm shallower and 12-μm deeper (on average), respectively. Intacs segment thickness does not influence implantation depth. Intacs segments implanted in the same eye do not share similar implantation depths. Stromal compression is likely to occur.ConclusionIntacs are implanted at a shallower depth than intended. The 'pocketing' stage prior to implantation most likely has a stronger effect on the segment's final implantation depth than does the incisions' depth.
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Reshaping procedures for the surgical management of corneal ectasia. J Cataract Refract Surg 2015; 41:842-72. [PMID: 25840308 DOI: 10.1016/j.jcrs.2015.03.010] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Revised: 07/15/2014] [Accepted: 07/23/2014] [Indexed: 12/31/2022]
Abstract
UNLABELLED Corneal ectasia is a progressive, degenerative, and noninflammatory thinning disorder of the cornea. Recently developed corneal reshaping techniques have expanded the treatment armamentarium available to the corneal specialist by offering effective nontransplant options. This review summarizes the current evidence base for corneal collagen crosslinking, topography-guided photorefractive keratectomy, and intrastromal corneal ring segment implantation for the treatment of corneal ectasia by analyzing the data published between the years 2000 and 2014. FINANCIAL DISCLOSURE No author has a financial or proprietary interest in any material or method mentioned.
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Mohammadpour M, Hahemi H, Jabbarvand M. Technique of simultaneous femtosecond laser assisted Myoring implantation and accelerated intrastromal collagen cross-linking for management of progressive keratoconus: A novel technique. Cont Lens Anterior Eye 2015; 39:9-14. [PMID: 26324416 DOI: 10.1016/j.clae.2015.06.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Revised: 06/08/2015] [Accepted: 06/29/2015] [Indexed: 11/25/2022]
Abstract
PURPOSE To describe a novel surgical technique for the management of progressive keratoconus by simultaneous femtosecond laser-assisted Myoring implantation and accelerated corneal intrastromal collagen cross-linking with Dextran Free Riboflavin. METHODS After creating a corneal pocket with femtosecond laser, Dextran Free Riboflavin was injected into the intrastromal pocket. Then the Myoring was implanted in the corneal pocket and accelerated corneal intrastromal collagen cross-linking was performed with no epithelial debridement. RESULTS The cornea remained clear and the central keratometry was decreased significantly with marked improvement in uncorrected visual acuity up to two years following treatment. Anterior segment OCT revealed good centration and intended implant depth with desirable increase in the corneal stromal reflectivity confirming effective collagen cross-linking. CONCLUSION Simultaneous femtosecond laser-assisted Myoring implantation and accelerated corneal intrastromal collagen cross-linking with Dextran Free Riboflavin is a safe and effective technique for management of keratoconus and improving vision.
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Affiliation(s)
- Mehrdad Mohammadpour
- Eye Research Center, Farabi Eye Center of Excellency, Tehran University of Medical Sciences, Faculty of Medicine, Tehran, Iran
| | - Hassan Hahemi
- Eye Research Center, Farabi Eye Center of Excellency, Tehran University of Medical Sciences, Faculty of Medicine, Tehran, Iran
| | - Mahmoud Jabbarvand
- Eye Research Center, Farabi Eye Center of Excellency, Tehran University of Medical Sciences, Faculty of Medicine, Tehran, Iran
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Sakla H, Altroudi W, Muñoz G, Albarrán-Diego C. Simultaneous topography-guided partial photorefractive keratectomy and corneal collagen crosslinking for keratoconus. J Cataract Refract Surg 2015; 40:1430-8. [PMID: 25135534 DOI: 10.1016/j.jcrs.2013.12.017] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Revised: 11/11/2013] [Accepted: 12/04/2013] [Indexed: 10/24/2022]
Abstract
PURPOSE To report the visual, refractive, and clinical outcomes of simultaneous topography-guided partial photorefractive keratectomy (PRK) and corneal collagen crosslinking (CXL) in eyes with keratoconus. SETTING Private practice surgery center, Dubai, United Arab Emirates. DESIGN Retrospective cohort study. METHODS Refraction, uncorrected (UDVA) and corrected (CDVA) distance visual acuities, flat and steep keratometry (K) readings, and complications were evaluated 1, 3, 6, and 12 months postoperatively. RESULTS The study enrolled 31 eyes of 31 patients aged 21 to 42 years. All study parameters showed a statistically significant improvement at 3, 6, and 12 months over baseline values. At 12 months, the mean UDVA improved to 0.23 logMAR±0.33 (SD) from 0.79±0.36 logMAR (P<.001) and the CDVA improved to 0.06±0.07 logMAR from 0.28±0.20 logMAR (P<.001). The mean defocus decreased from 3.45±1.60 diopters (D) to 1.88±1.58 D (P<.001). The flat K and steep K readings showed significant flattening. The mean refractive astigmatism decreased from -2.77±1.47 D to -0.98±0.76 D (P<.001). The improvement in study parameters plateaued after 3 months. CONCLUSION Simultaneous topography-guided partial PRK and CXL was effective, safe, and stable in keratoconus patients. FINANCIAL DISCLOSURE No author has a financial or proprietary interest in any material or method mentioned.
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Affiliation(s)
- Hani Sakla
- From Ebsaar Eye Surgery Center, Dubai, United Arab Emirates
| | | | - Gonzalo Muñoz
- From Ebsaar Eye Surgery Center, Dubai, United Arab Emirates
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Refractive and topographic effects of single-segment intrastromal corneal ring segments in eyes with moderate to severe keratoconus and inferior cones. J Cataract Refract Surg 2015; 41:1434-40. [DOI: 10.1016/j.jcrs.2014.10.037] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 10/24/2014] [Accepted: 10/26/2014] [Indexed: 11/18/2022]
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Abstract
OBJECTIVES To review and summarize relevant studies on combined use of corneal crosslinking and intracorneal ring segments (ICRS) for the treatment of corneal ectasia. METHODS A literature search was performed using the key words "corneal collagen cross-linking" and "intra-corneal ring segments." RESULTS Crosslinking is a well-accepted treatment option for corneal ectasia and can be combined with corneal ICRS insertion as needed. The advent of crosslinking has dramatically reduced the number of corneal transplants performed for patients with keratoconus or postrefractive ectasia. Intracorneal ring segments, although flatten the corneal surface, do not prevent the progression of corneal ectasia. This is why the combination of crosslinking and ICRS is potentially synergistic. Previous studies reported that combining these two complementary interventions has been shown to be safe and effective. CONCLUSIONS The effects of ICRS are enhanced and stabilized by crosslinking, but the ideal combined technique is not known at present.
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Hashemian MN, Zare MA, Mohammadpour M, Rahimi F, Fallah MR, Panah FK. Outcomes of Single Segment Implantation of Conventional Intacs versus Intacs SK for Keratoconus. J Ophthalmic Vis Res 2015; 9:305-9. [PMID: 25667729 PMCID: PMC4307661 DOI: 10.4103/2008-322x.143359] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Accepted: 02/15/2014] [Indexed: 11/09/2022] Open
Abstract
Purpose: To compare the visual, refractive, and keratometric outcomes of single-segment conventional and severe keratoconus (SK) types of Intacs for correction of inferior keratoconus (KCN). Methods: A total number of 41 consecutive eyes of 23 patients with a diagnosis of inferior KCN underwent Intacs implantation. Eight eyes were excluded due to postoperative complications (4 eyes) and loss to follow-up (4 eyes) and finally 33 eyes underwent statistical analysis. Two groups were created according to Intacs type insertion; conventional group (17 eyes) and SK groups (16 eyes). Intracorneal ring segments (ICRS) implantation was indicated in keratoconic patients with contact-lens intolerance or reduced best spectacle-corrected visual acuity (BSCVA). Results: In the conventional group, mean uncorrected distance visual acuity (UCDVA) improved from 0.45 ± 0.41 preoperatively to 0.69 ± 0.39 six months after surgery representing a gain of 2 Snellen lines, and in the SK group mean UCDVA changed from 0.40 ± 0.35 preoperatively to 0.58 ± 0.48 equivalent to two Snellen lines improvement 6 months after operation (P = 0.48). Mean preoperative BSCVA in the conventional group improved from 0.72 ± 0.41 to 0.86 ± 0.39 (2 lines improvement) postoperatively and in the SK group improved from 0.71 ± 0.69 to 0.75 ± 0.45 (0.50 line improvement) (P = 0.29). Mean preoperative spherical equivalent (SE) decreased from −4.86 ± 2.26 D to −3.57 ± 2.21 D (conventional group) and from −4.20 ± 1.82 D to −3.60 ± 1.89 D (P = 0.34), mean astigmatism (AST) decreased from −5.20 ± 2.07 D and −4.50 ± 2.26 D to −4.02 ± 2.57 D and − 3.18 ± 2.14 D in the conventional and SK groups, respectively (P = 0.68). Finally, mean K min decreased from 47.11 ± 2.51 D to 45.40 ± 3.30 D in the conventional group and from 45.05 ± 2.59 D to 44 ± 3.88 D in the SK group (P = 0.63) and mean K max was decreased from 52.82 ± 3.23 D to 50.52 ± 3.57 D and from 49.72 ± 3.17 D to 48.55 ± 4.50 D, respectively (P = 0.48). Conclusion: Single-segment implantation of conventional and SK Intacs improved UCDVA and BSCVA, decreased corneal AST and keratometry in both groups with comparable outcomes.
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Affiliation(s)
- Mohammad Nasser Hashemian
- Cornea Department, Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohammad Ali Zare
- Cornea Department, Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Mehrdad Mohammadpour
- Cornea Department, Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Firouzeh Rahimi
- Cornea Department, Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohammad Reza Fallah
- Cornea Department, Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Fereydoun Keramat Panah
- Cornea Department, Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
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Al Muammar A. Comparison of visual, refractive and topographic keratometry outcomes of Intacs and Intacs SK in mild to moderate keratoconus eyes. Middle East Afr J Ophthalmol 2015; 22:74-9. [PMID: 25624678 PMCID: PMC4302481 DOI: 10.4103/0974-9233.148353] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose: The purpose was to evaluate and compare the visual and refractive outcomes, topographic keratometry (K) and complications of Intacs and Intacs SK for mild to moderate keratoconus. Methods: In this retrospective study, all mild to moderate keratoconus eyes that underwent implantation of Intacs (Intacs group) or Intacs SK (Intacs SK group) with minimum follow-up of 12 months were included. Preoperative and postoperative uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction, manifest cylinder, spherical equivalent (SE), minimum topographic keratometry, maximum topographic keratometry, and average topographic keratometry were compared in both groups. Results: There were 16 eyes in the Intacs group and 18 eyes in the Intacs SK group. Preoperatively, both groups were comparable for most parameters except gender and minimum K and average K. At 6 months postoperatively there were statistically significant improvements in UDVA, CDVA, manifest sphere, SE, minimum K, maximum K, and average K (P < 0.05, all comparisons). Manifest cylinder improved at 6 months, but the improvement was not statistically significant (P > 0.05). The outcomes remained stable with no statistically significant differences between the 6 and 12 months visits. There were no complications in both groups. Conclusion: Both models of Intacs significantly improved vision and refractive outcomes, and topographic keratometry in cases of mild to moderate keratoconus. Intacs SK provided better (not statistically significant) results.
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Affiliation(s)
- Abdulrahman Al Muammar
- Department of Ophthalmology, College of Medicine, King Abdul Aziz University Hospital, King Saud University, Riyadh, Kingdom of Saudi Arabia
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Peña-García P, Alió JL, Vega-Estrada A, Barraquer RI. Internal, corneal, and refractive astigmatism as prognostic factors for intrastromal corneal ring segment implantation in mild to moderate keratoconus. J Cataract Refract Surg 2014; 40:1633-44. [DOI: 10.1016/j.jcrs.2014.01.047] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Revised: 12/18/2013] [Accepted: 01/07/2014] [Indexed: 12/26/2022]
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Karamichos D, Hjortdal J. Keratoconus: tissue engineering and biomaterials. J Funct Biomater 2014; 5:111-34. [PMID: 25215423 PMCID: PMC4192608 DOI: 10.3390/jfb5030111] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Revised: 08/26/2014] [Accepted: 09/03/2014] [Indexed: 12/20/2022] Open
Abstract
Keratoconus (KC) is a bilateral, asymmetric, corneal disorder that is characterized by progressive thinning, steepening, and potential scarring. The prevalence of KC is stated to be 1 in 2000 persons worldwide; however, numbers vary depending on size of the study and regions. KC appears more often in South Asian, Eastern Mediterranean, and North African populations. The cause remains unknown, although a variety of factors have been considered. Genetics, cellular, and mechanical changes have all been reported; however, most of these studies have proven inconclusive. Clearly, the major problem here, like with any other ocular disease, is quality of life and the threat of vision loss. While most KC cases progress until the third or fourth decade, it varies between individuals. Patients may experience periods of several months with significant changes followed by months or years of no change, followed by another period of rapid changes. Despite the major advancements, it is still uncertain how to treat KC at early stages and prevent vision impairment. There are currently limited tissue engineering techniques and/or "smart" biomaterials that can help arrest the progression of KC. This review will focus on current treatments and how biomaterials may hold promise for the future.
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Affiliation(s)
- Dimitrios Karamichos
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, 608 Stanton L. Young Blvd, DMEI PA-409, Oklahoma City, OK 73104, USA.
| | - Jesper Hjortdal
- Department of Ophthalmology, Aarhus University Hospital, Aarhus C DK-800, Denmark.
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Shetty R, D'Souza S, Ramachandran S, Kurian M, Nuijts RMMA. Decision making nomogram for intrastromal corneal ring segments in keratoconus. Indian J Ophthalmol 2014; 62:23-8. [PMID: 24492498 PMCID: PMC3955066 DOI: 10.4103/0301-4738.126170] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Purpose: To create a nomogram for the insertion of intrastromal corneal ring segments (ICRS) (Intacs® ) in eyes with keratoconus. Setting: Tertiary eye care center in South India. Materials and Methods: This prospective, non-randomized, interventional case series used a self-designed decision-making nomogram for the selection of ICRS in keratoconus patients based on the centration of the cone, mean refractive spherical equivalent (MRSE), and mean keratometry (Km) values. The 3, 6, and 12 months clinical outcomes were compared to historical controls. Primary endpoints were improvement in uncorrected and best-corrected vision and change in the keratometric values. Results: Group A comprised of 52 eyes of 50 patients that followed the nomogram, while Group B comprised of 25 eyes of 23 non-nomogram historical controls matched for baseline parameters. In Group A, the uncorrected distance visual acuity (UDVA) improved from 0.16 ± 0.15 to 0.25 ± 0.16 (P < 0.001), corrected distance visual acuity (CDVA) from 0.58 ± 0.2 to 0.69 ± 0.21 (P = 0.022), MRSE from -5.41 ± 4.94 to -1.71 ± 2.88 (P < 0.001), Km from 51.77 ± 5.45 to 48.63 ± 4.37 (P < 0.001), and astigmatism reduced from 5.86 ± 2.61 to 4.91 ± 2.72 diopters (P < 0.001).In Group B, improvement in the average MRSE was from -6.44 ± 5.32 to -3.26 ± 2.82 (P < 0.013) and in the average Km from 53.64 ± 5.32 to 50.31 ± 5.02 (P < 0.001). Other parameters did not improve significantly. A statistically significant difference was present in the percentage of patients achieving a good clinical outcome between the two groups (P < 0.001; Chi-square). Conclusion: The nomogram provides a means to choose the appropriate ICRS, hence improving the outcome in patients with keratoconus.
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Affiliation(s)
- Rohit Shetty
- Head of Department, Refractive Surgery, Narayana Nethralaya Superspeciality Eye Institute, Bangalore, Karnataka, India
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Alio JL, Vega-Estrada A, Esperanza S, Barraquer RI, Teus MA, Murta J. Intrastromal corneal ring segments: how successful is the surgical treatment of keratoconus? Middle East Afr J Ophthalmol 2014; 21:3-9. [PMID: 24669139 PMCID: PMC3959038 DOI: 10.4103/0974-9233.124076] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
This review evaluates the outcomes of intrastromal corneal ring segment (ICRS) implantation for the treatment of keratoconus considering a new grading system based on the preoperative visual impairment of the patient. Additionally, a five-year follow-up analysis of patients with stable and progressive keratoconus is performed in order to assess the long term stability of the surgical procedure. Corrected distance visual acuity decreased statistically significantly in patients with mild keratoconus (P < 0.01) but statistically significantly increased in all other grades (P < 0.05). The improvement in visual acuity and the decrease of keratometric and aberrometric values were stable throughout a long period of time in patients with stable keratoconus. In patients with progressive form keratoconus, a significant improvement was found immediately after the procedure, however clinically relevant regression greater than 3 D was observed at the end of the follow up period.
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Affiliation(s)
- Jorge L Alio
- Keratoconus Unit, Vissum Coorporation, Alicante, Spain ; Division of Ophthalmology, Universidad Miguel Hernández, Alicante, Spain
| | - Alfredo Vega-Estrada
- Keratoconus Unit, Vissum Coorporation, Alicante, Spain ; Division of Ophthalmology, Universidad Miguel Hernández, Alicante, Spain
| | - Santiago Esperanza
- Keratoconus Unit, Vissum Coorporation, Alicante, Spain ; Division of Ophthalmology, Universidad Miguel Hernández, Alicante, Spain
| | - Rafael I Barraquer
- Anterior Segment Department, Centro de Oftalmología Barraquer, Barcelona, Spain
| | - Miguel A Teus
- Anterior Segment Department, Vissum Corporation, Madrid, Spain
| | - Joaquim Murta
- Ophthalmology Department, Coimbra University Hospital, Coimbra, Portugal
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Ganesh S, Shetty R, D'Souza S, Ramachandran S, Kurian M. Intrastromal corneal ring segments for management of keratoconus. Indian J Ophthalmol 2014; 61:451-5. [PMID: 23925336 PMCID: PMC3775086 DOI: 10.4103/0301-4738.116065] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Keratoconus is a progressive corneal ectasia, which can be managed both by conservative measures like glasses or contact lenses in non-progressive cases or surgical procedures like collagen crosslinking (CXL) with or without adjuvant measures like intrastromal corneal rings segments (ICRS) or topography guided ablation. Various kinds of ICRS are available to the surgeon, but it is most essential to be able to plan the implantation of the ring to optimize outcomes.
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Affiliation(s)
- Sri Ganesh
- Department of Refractive Surgery, Narayana Nethralaya, Superspeciality Eye Institute, Bangalore, Karnataka, India
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Ferreira TB, Güell JL, Manero F. Combined Intracorneal Ring Segments and Iris-Fixated Phakic Intraocular Lens for Keratoconus Refractive and Visual Improvement. J Refract Surg 2014; 30:336-41. [DOI: 10.3928/1081597x-20140319-01] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2013] [Accepted: 12/18/2013] [Indexed: 11/20/2022]
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Hashemi H, Yazdani-Abyaneh A, Beheshtnejad A, Jabbarvand M, Kheirkhah A, Ghaffary SR. Efficacy of intacs intrastromal corneal ring segment relative to depth of insertion evaluated with anterior segment optical coherence tomography. Middle East Afr J Ophthalmol 2014; 20:234-8. [PMID: 24014988 PMCID: PMC3757634 DOI: 10.4103/0974-9233.114800] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
AIM To evaluate the effect of implantation depth of Intacs microthin prescription inserts (Addition Technology Inc, Fremont, California) on visual and topographic outcomes in patients with post- laser-assisted in situ keratomileusis (LASIK) ectasias. SETTINGS AND DESIGN Retrospective, observational case series. MATERIALS AND METHODS In this case series, 16 eyes of 12 patients were evaluated. All cases were post-LASIK ectasia that had undergone intrastromal corneal ring segment (ICRS) implantation. The planned insertion depth was 70% of stromal thickness using a manual dissector. At least 12 months postoperatively, all eyes underwent Visante (Carl Zeiss Meditec) AS-OCT to determine insertion depth. Cases were categorized into 3 groups based on the measured implantation depth: 40-59% thickness; 60-79% thickness; and ≥80% thickness. Visual, refractive and topographic outcomes were evaluated relative to implantation depth. RESULTS The lowest improvement in the study parameters ocurred when the implantation depth was ≥80%. In this group, uncorrected visual acuity (UCVA) and best spectacle corrected VA (BSCVA) improved less than 0.5 lines. Manifest refractive spherical equivalent (MRSE) and mean keratometry (Km) change was less than 0.5 diopters (D). The greatest improvements were observed with implantation depth of 60-79% where UCVA and BSCVA increased by 4.5 and 2.5 lines respectively, and MRSE and Km changed by approximately 2.00 D. Less improvement was found when ICRS were implanted between 40-59% of stromal thickness. CONCLUSION Implantation of ICRS greater than 80% of stromal thickness may have no effect on visual and topographic status.
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Affiliation(s)
- Hassan Hashemi
- Noor Ophthalmology Research Center, Noor Eye Hospital, Tehran, Iran ; Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
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Kotb AMEM, Hantera M. Efficacy and safety of Intacs SK in moderate to severe keratoconus. Middle East Afr J Ophthalmol 2014; 20:46-50. [PMID: 23580851 PMCID: PMC3617527 DOI: 10.4103/0974-9233.106386] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Purpose: To examine the safety and efficacy of Intacs SK for moderate to severe keratoconus (KC) using femtosecond technology. Materials and Methods: This prospective, non-comparative study included 37 contact lens intolerant keratoconic eyes (stage II-III) of 24 patients who underwent femtosecond-assisted Intacs SK implantation. Inclusion criteria were mean K readings <56.00 D, corneal thickness >400 μm at the incision site, mesopic pupil <6.50 mm. Evaluation included manifest refraction, slitlamp examination, corneal topography, uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA). P < 0.05 was statistically significant. Results: Thirty-one (83.8%) eyes were classified as Amsler-Krumeich′s stage II and 6 (16.2%) were stage III. Mean central pachymetry was 490.3 ± 37.4 μm. UDVA at 6 months post-operatively was significantly better than pre-operatively (0.90 log MAR ± 0.52 standard deviation [SD] versus 0.32 ± 0.27 logMAR; respectively, P < 0.0001), as was the spherical equivalent (SEq) (−3.64 ± 2.52 D vs. −1.84 ± 2.2 D; P < 0.0001). The mean CDVA and manifest cylinder improved compared with pre-operatively (P = 0.319 and P = 0.078, respectively). Average keratometry decreased significantly from 48.50 ± 3.08 D to 44.40 ± 3.03 D (P < 0.0001). Conclusion: Implantation of Intacs SK using femtosecond laser in moderate to severe KC is safe and effective.
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Vega-Estrada A, Alió JL, Brenner LF, Burguera N. Outcomes of intrastromal corneal ring segments for treatment of keratoconus: five-year follow-up analysis. J Cataract Refract Surg 2013; 39:1234-40. [PMID: 23747207 DOI: 10.1016/j.jcrs.2013.03.019] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Revised: 03/01/2013] [Accepted: 03/07/2013] [Indexed: 11/29/2022]
Abstract
PURPOSE To report the long-term refractive and optical quality outcomes of patients with intrastromal corneal ring segments (ICRS) to treat keratoconus and to analyze the results according to the patients' age. SETTING Vissum Instituto Oftalmologico de Alicante, Alicante, Spain. DESIGN Case series. METHODS The uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction, corneal topography, and aberrometry were evaluated before and after ICRS implantation in eyes with keratoconus. The follow-up was 5 years in all cases. RESULTS The study comprised 51 eyes (35 patients; age range 15 to 56 years). After 6 months, the improvement in the UDVA, CDVA, spherical equivalent, and mean keratometry (K) value was statistically significant (P<.05). Five years postoperatively, these parameters remained unchanged (P=.31). Slight regression (0.97 diopter [D]) was observed in the mean K between 6 months and 5 years; the regression was not statistically significant (P=.39). Anterior corneal aberrometric values decreased; however, the changes were not statistically significant (P ≥.10). Linear regression analysis showed no correlation between the age of the patients and the changes observed in the mean K throughout the follow-up (P>.05, r(2) = 0.001). CONCLUSIONS Intrastromal corneal ring segment implantation in keratoconus patients provided long-term improvement of the refractive and topographic status. There was no correlation between the amount of individual changes in the mean K reading and patient age.
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Alfonso JF, Fernández-Vega Cueto L, Baamonde B, Merayo-Lloves J, Madrid-Costa D, Montés-Micó R. Inferior Intrastromal Corneal Ring Segments in Paracentral Keratoconus With No Coincident Topographic and Coma Axis. J Refract Surg 2013; 29:266-72. [DOI: 10.3928/1081597x-20130318-06] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Accepted: 01/24/2013] [Indexed: 11/20/2022]
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Vega-Estrada A, Alio JL, Brenner LF, Javaloy J, Plaza Puche AB, Barraquer RI, Teus MA, Murta J, Henriques J, Uceda-Montanes A. Outcome analysis of intracorneal ring segments for the treatment of keratoconus based on visual, refractive, and aberrometric impairment. Am J Ophthalmol 2013; 155:575-584.e1. [PMID: 23218702 DOI: 10.1016/j.ajo.2012.08.020] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Revised: 08/29/2012] [Accepted: 08/29/2012] [Indexed: 01/13/2023]
Abstract
PURPOSE To analyze the outcomes of intracorneal ring segment (ICRS) implantation for the treatment of keratoconus based on preoperative visual impairment. DESIGN Multicenter, retrospective, nonrandomized study. METHODS A total of 611 eyes of 361 keratoconic patients were evaluated. Subjects were classified according to their preoperative corrected distance visual acuity (CDVA) into 5 different groups: grade I, CDVA of 0.90 or better; grade II, CDVA equal to or better than 0.60 and worse than 0.90; grade III, CDVA equal to or better than 0.40 and worse than 0.60; grade IV, CDVA equal to or better than 0.20 and worse than 0.40; and grade plus, CDVA worse than 0.20. Success and failure indices were defined based on visual, refractive, corneal topographic, and aberrometric data and evaluated in each group 6 months after ICRS implantation. RESULTS Significant improvement after the procedure was observed regarding uncorrected distance visual acuity in all grades (P < .05). CDVA significantly decreased in grade I (P < .01) but significantly increased in all other grades (P < .05). A total of 37.9% of patients with preoperative CDVA 0.6 or better gained 1 or more lines of CDVA, whereas 82.8% of patients with preoperative CDVA 0.4 or worse gained 1 or more lines of CDVA (P < .01). Spherical equivalent and keratometry readings showed a significant reduction in all grades (P ≤ .02). Corneal higher-order aberrations did not change after the procedure (P ≥ .05). CONCLUSIONS Based on preoperative visual impairment, ICRS implantation provides significantly better results in patients with a severe form of the disease. A notable loss of CDVA lines can be expected in patients with a milder form of keratoconus.
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Alfonso JF, Lisa C, Merayo-Lloves J, Cueto LFV, Montés-Micó R. Intrastromal corneal ring segment implantation in paracentral keratoconus with coincident topographic and coma axis. J Cataract Refract Surg 2012; 38:1576-82. [DOI: 10.1016/j.jcrs.2012.05.031] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2012] [Revised: 05/05/2012] [Accepted: 05/08/2012] [Indexed: 10/28/2022]
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Kapasi M, Rocha G. Comparison of visual and refractive outcomes following Intacs implantation in keratoconus eyes with central and eccentric cones. Can J Ophthalmol 2012; 47:354-9. [DOI: 10.1016/j.jcjo.2012.04.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2011] [Revised: 02/14/2012] [Accepted: 03/29/2012] [Indexed: 10/26/2022]
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Visual quality after posterior chamber phakic intraocular lens implantation in keratoconus. J Cataract Refract Surg 2012; 38:1050-7. [DOI: 10.1016/j.jcrs.2011.12.035] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2011] [Revised: 11/30/2011] [Accepted: 12/21/2011] [Indexed: 11/22/2022]
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Bedi R, Touboul D, Pinsard L, Colin J. Refractive and Topographic Stability of Intacs in Eyes With Progressive Keratoconus: Five-year Follow-up. J Refract Surg 2012; 28:392-6. [DOI: 10.3928/1081597x-20120509-01] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2011] [Accepted: 04/24/2012] [Indexed: 11/20/2022]
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