Femtosecond laser–assisted intrastromal corneal ring segment implantation for high astigmatism correction after penetrating keratoplasty

Purpose: To analyze changes of functional parame¬ters and aberrations before fitting and after using rigid gas-permeable scleral lenses (RGPSCL) in patients with irregular cornea. Material and methods. 21 patients (29 eyes) with irregular astigmatism of various etiology were enrolled in this study. The patients could not achieve good visual aсuity in glasses, standard soft or rigid corneal contact lenses. Complex ophthalmologic examination was per¬formed: autorefractometry, visometry, biomicroscopy, computer corneal topography, aberrometry on “OPD-Scan II” (“Nidek”, Japan) before fitting scleral lenses and during the period of their wearing. Results and discussion. The results demonstrat¬ed significant visual acuity improvement after RGP¬SCL fitting in all observed patients. UCVA amounted to 0.1±0.18, BCVA in glasses amounted to 0.4±0.26, BCVA in RGPSCL amounted to 0.7±0.1. An increase of best-corrected visual acuity in RGPSCL was statistically significant in patients after keratoplasty, after intra-stromal corneal ring segments (ICRS) implantation, af¬ter refractive laser surgery (RLS) and in cases of mixed astigmatism. We have found that the correction of ker¬atoconus with the use of RGPSCL resulted in a decrease of the root mean square value (RMS), measured in the 3 mm and 5 mm zones by 2.5 times and 4 times, re¬spectively. In patients wearing RGPSCL after kerato¬plasty, statistically significant decrease in RMS was observed in the 3 mm zone (by 3.85 times) and in the 5 mm zone (by 2.99 times). In patients wearing RGPSCL after implantation of intrastromal corneal ring segment (ICRS), RMS in the 3 mm zone decreased by 1.5 times. In patients wearing RGPSCL after refractive laser surgery (RLS) RMS was 2.5 times lower in the 3 mm zone and 2.8 times lower in the 5 mm zone. In case of mixed astigmatism correction with RGPSCL, RMS increased by 1.6 times in the 3 mm zone and practically did not change in the 5 mm zone. Conclusion. The results obtained demonstrated significant visual acuity improvement in all observed patients. The sub-lens-space filled with tear forms a unified “cornea-tear-scleral contact lens” optic system that corrects unevenness of cornea, decreases amount of high-order aberrations (HOA) and provides a clear stable vision.

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The Clinical Results of Intrastromal Corneal Ring Segment Implantation Using a Femtosecond Laser in Keratectasia

Journal of the Korean Ophthalmological Society ◽

10.3341/jkos.2010.51.1.1 ◽

2010 ◽

Vol 51 (1) ◽

pp. 1 ◽

Cited By ~ 1

Author(s):

Chang Il Ha ◽

Suk Kyue Choi ◽

Do Hyung Lee ◽

Jin Hyoung Kim

Keyword(s):

Femtosecond Laser ◽

Clinical Results ◽

Intrastromal Corneal Ring ◽

Ring Segment

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Intrastromal corneal ring segment implantation to correct astigmatism after penetrating keratoplasty

Journal of Cataract & Refractive Surgery ◽

10.1016/j.jcrs.2011.12.037 ◽

2012 ◽

Vol 38 (6) ◽

pp. 1006-1013 ◽

Cited By ~ 10

Author(s):

Sandro Coscarelli ◽

Guilherme Ferrara ◽

Jose F. Alfonso ◽

Paulo Ferrara ◽

Jesús Merayo-Lloves ◽

...

Keyword(s):

Penetrating Keratoplasty ◽

Intrastromal Corneal Ring ◽

Ring Segment

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Anterior Segment Changes After Femtosecond Laser-Assisted Implantation of a 355-Degree Intrastromal Corneal Ring Segment in Advanced Keratoconus

Cornea ◽

10.1097/ico.0000000000001702 ◽

2018 ◽

Vol 37 (11) ◽

pp. 1438-1443 ◽

Cited By ~ 3

Author(s):

Mohamed Samy Abd Elaziz ◽

Abdel Rahman El Saebay Sarhan ◽

Asmaa Mohammed Ibrahim ◽

Haidy Abd Elshafy Haggag

Keyword(s):

Femtosecond Laser ◽

Anterior Segment ◽

Intrastromal Corneal Ring ◽

Ring Segment

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Intrastromal Corneal Ring Segments for Astigmatism Correction after Deep Anterior Lamellar Keratoplasty

Journal of Ophthalmology ◽

10.1155/2017/8689017 ◽

2017 ◽

Vol 2017 ◽

pp. 1-7 ◽

Cited By ~ 4

Author(s):

Júlio C. D. Arantes ◽

Sandro Coscarelli ◽

Paulo Ferrara ◽

Luana P. N. Araújo ◽

Marcos Ávila ◽

...

Keyword(s):

Contact Lenses ◽

Corneal Astigmatism ◽

Lamellar Keratoplasty ◽

Deep Anterior Lamellar Keratoplasty ◽

Spherical Equivalent ◽

Astigmatism Correction ◽

Intrastromal Corneal Ring ◽

Anterior Lamellar Keratoplasty ◽

Corrected Distance Visual Acuity ◽

Ring Segment

Background. To evaluate the change in corneal astigmatism after intrastromal corneal ring segment (ICRS) implantation in keratoconus patients with previous deep anterior lamellar keratoplasty (DALK). Design was a longitudinal, retrospective, interventional study. The study included 25 eyes of 24 patients with keratoconus who had DALK performed at least two years prior to ICRS implantation. All patients had a clear corneal graft with up to 8.00 D of corneal astigmatism and intolerance to contact lenses. The studied parameters were age, sex, corrected distance visual acuity (CDVA), maximum keratometry (K1), minimum keratometry (K2), spherical equivalent, and astigmatism. There was a statistically significant decrease in the postintervention analysis as follows: 3.5 D reduction in K1 (p<0.001); 1.53 D in K2 (p=0.005); and 2.52 D (p<0.001) in the average K. The spherical equivalent reduced from −3.67 D (±2.74) to −0.71 D (±2.35) (p<0.001). The topographic astigmatism reduced from 3.87 D preoperatively to 1.90 D postoperatively (p<0.001). The CDVA improved from 0.33 (±0.10) to 0.20 (±0.09, p<0.001). ICRS implantation is a useful option for the correction of astigmatism after DALK as it yields significant visual, topographic, and refractive results.

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Visual and refractive outcomes and tomographic changes after femtosecond laser-assisted intrastromal corneal ring segment implantation in patients with keratoconus

Journal of Ophthalmic and Vision Research ◽

10.4103/jovr.jovr_42_17 ◽

2018 ◽

Vol 13 (4) ◽

pp. 376

Author(s):

SeyedJavad Hashemian ◽

Nooshin Farshchian ◽

Alireza Foroutam-Jazi ◽

MohammadEbrahim Jafari ◽

MahsaSadat Hashemian ◽

...

Keyword(s):

Femtosecond Laser ◽

Refractive Outcomes ◽

Intrastromal Corneal Ring ◽

Ring Segment

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Outcomes of a Single-Segment Intrastromal Corneal Ring in Early Keratoconus Versus Early Pellucid Marginal Degeneration

10.21203/rs.3.rs-471860/v1 ◽

2021 ◽

Author(s):

Seyed Javad Hashemian ◽

Parya Abdolalizadeh ◽

Leila Ghiasian ◽

Hossein Aghaei ◽

Ali Hadavandkhani ◽

...

Keyword(s):

Visual Acuity ◽

Femtosecond Laser ◽

Early Stage ◽

Interventional Study ◽

Short Term ◽

Single Segment ◽

Corrected Visual Acuity ◽

Intrastromal Corneal Ring ◽

Ring Segment ◽

Outpatient Center

Abstract Purpose: To determine the effect of a single-segment intrastromal corneal ring segment (ICRS;Intacs-SK) on early keratoconus (KCN) or pellucid marginal degeneration (PMD).Methods: It is a prospective interventional study. One-hundred-twenty-four eyes (99 patients) with KCN and 36 eyes (26 patients) with PMD at early stage (the maximum keratometric reading less than 55 diopters) were included to ICRS implantation using femtosecond laser at a tertiary university-based hospital and a private outpatient center. The uncorrected distance and spectacle-corrected visual acuity (UDVA and SCDVA), manifest spherical and cylindrical refractions, and keratometry indices were measured preoperatively and postoperatively, 1 week, 2 and 6 months.Results: One week after surgery, significant improvements were observed in UDVA, SCDVA, cylinder and keratometry readings of both KCN and PMD groups (all P<0.05) with no significant changes afterwards. No significant change occurred in the sphere refraction of PMD group (P=0.10) in contrast to KCN group (P<0.001). Corneal irregularity of KCN group in central 3 and 5 mm zones increased at 1 week (both P<0.001) and then continued to decrease up to 6 months. However, the corneal irregularity of PMD group had significant reduction only at 1 week in 5-mm zone (P=0.02) and 2 months in 3-mm zone (P=0.01) postoperatively. The final efficacy indexes were 1.44±0.71 and 0.87±0.40 in KCN and PMD groups, respectively. Conclusion: Visual acuity and keratometry values reached stability at 1 week, after one-segment Intacs-SK implantation in KCN and PMD groups. The short-term efficacy of the procedure was more in early KCN compared to early PMD.

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Correction of postkeratoplastic astigmatism by intrastromal corneal segments implantation using a femtosecond laser

Acta biomedica scientifica ◽

10.29413/abs.2021-6.6-1.6 ◽

2021 ◽

Vol 6 (6-1) ◽

pp. 48-55

Author(s):

N. A. Pozdeyeva ◽

M. V. Sinitsyn ◽

A. E. Terentieva ◽

O. V. Shlenskaya

Keyword(s):

Visual Acuity ◽

Femtosecond Laser ◽

Penetrating Keratoplasty ◽

Biomechanical Properties ◽

Corneal Graft ◽

Corneal Resistance Factor ◽

Astigmatism Correction ◽

Corrected Visual Acuity ◽

Uncorrected Visual Acuity ◽

Best Corrected Visual Acuity

Background. After penetrating keratoplasty, mild to high induced corneal astigmatism was observed in each case. The existing choice of correction of postkeratoplastic astigmatism is aimed at fi nding an individual approach in order to compensate for it and not weaken the biomechanical properties of the corneal graft.The aim: to analyze the clinical, functional, and morphological results of postkeratoplastic astigmatism correction by implantation of intrastromal corneal segments using a femtosecond laser.Methods. 22 patients were examined before and 1 year after surgery. The operation was performed under local anesthesia: stage I – an intrastromal tunnel was formed using a femtosecond laser “Femto Visum” 1 MHz (Optosystems, Russia); stage II – the intrastromal corneal segments were implanted. The results were assessed using standard and special research methods using optical coherence tomography Visante OCT (Zeiss, Germany), keratotopography (Tomey-5, Japan), optical corneal analyzer ORA (Reichert, USA), laser tindalemetry FC-2000 (Kowa, Japan) and confocal microscope Confoscan-4 (Nidek, Japan).Results. Before the operation, uncorrected visual acuity averaged 0.09 ± 0.05, after a year – 0.50 ± 0.16; best corrected visual acuity – 0.30 ± 0.12 and 0.60 ± 0.05 respectively; cylindrical component of refraction – –10.29 ± 3.12 and –2.20 ± 0.64 D respectively; mean keratometry value – 43.59 ± 2.14 and 38.56 ± 1.75 D respectively; corneal hysteresis – 7.92 ± 1.22 and 8.95 ± 1.05 mm Hg respectively; corneal resistance factor – 7.01 ± 1.81 and 8.44 ± 1.44 mm Hg respectively; protein fl ux in the moisture of the anterior chamber – 2.97 ± 0.28 and 3.04 ± 0.24 f/ms respectively; endothelial cell density – 1521 ± 327 and 1475 ± 419 cells/mm2 respectively.Conclusion. Intrastromal corneal segments implantation into a corneal graft using a femtosecond laser has efficiency and safety method in correcting postkeratoplastic astigmatism.

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