scholarly journals Changes in the 3D Corneal Structure and Morphogeometric Properties in Keratoconus after Corneal Collagen Crosslinking

Diagnostics ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 397 ◽  
Author(s):  
Ramón Alifa ◽  
David Piñero ◽  
José Velázquez ◽  
Jorge Alió del Barrio ◽  
Francisco Cavas ◽  
...  
Keyword(s):  
Corneal Thickness ◽  
Minimum Thickness ◽  
Collagen Crosslinking ◽  
Several Variables ◽  
Structure Changes ◽  
Corneal Structure ◽  
Corneal Collagen Crosslinking ◽  
Significant Regression ◽  
Corneal Collagen

Keratoconus is an ectatic disorder that is presently considered one of the most prevalent reasons for keratoplasty. Corneal collagen crosslinking (CXL) is the only proven treatment option available that is capable of halting the progression of the disease by stabilizing the cone in 90% of cases, and by also reducing refractive error and maximal keratometry. This study assesses, by means of a 3D morphogeometric analysis procedure developed by our research team, the corneal structure changes that occur immediately after CXL treatment and during a 6 month follow-up period. A total of 19 eyes from 19 patients diagnosed with keratoconus who underwent CXL were included, and several variables derived from the morphogeometric analysis were calculated and evaluated for the pre-operative, 3 month postoperative, and 6 month postoperative states. Significant reductions were detected in central corneal thickness and corneal spherical-like root mean square (RMS) 3 months after surgery, with non-significant regression of the effect afterward. Significant reductions in the total corneal area/volume were found, with some levels of regression after 6 months in certain volumetric parameters. In conclusion, the eyes with higher values for morphogeometric parameters—posterior apex deviation (PAD), anterior minimum thickness point deviation (AMTPD), and posterior minimum thickness point deviation (PMTPD)—seemed more likely to undergo aberrometric improvement as a result of CXL surgery.

scholarly journals MyoRing Implantation in Comparison with MyoRing Implantation Combined with Corneal Collagen Crosslinking for Keratoconus

2019 ◽  
Vol 16 (1S) ◽  
pp. 85-90
Author(s):  
G. M. Kazakbaeva
Keyword(s):  
Corneal Thickness ◽  
Efficacy And Safety ◽  
Collagen Crosslinking ◽  
Corrected Visual Acuity ◽  
Number Of Patients ◽  
Significant Difference ◽  
Corneal Collagen Crosslinking ◽  
The Difference ◽  
Corneal Collagen

Purpose: tо estimate the effectiveness of complete corneal ring (MyoRing) implantation compared with MyoRing implantation combined with corneal collagen crosslinking (CXL) for keratoconus treatment for 36 months follow-up. Patients and Methods. There were 101 patients (124 eyes) with progressing keratoconus aged 18–59 years in the study. Intracorneal rings were implanted in all patients. The patients were divided into 2 groups. MyoRing implantation was performed in a series of 59 patients (76 eyes) with keratoconus II–III Amsler classification, 42 patients (48 eyes) had MyoRing implantation combined with CXL. Implantation of a MyoRing in the corneal pocket was performed using a PocketMaker microkeratome and corneal intrastromal implantation system. Results. Keratometry was reduced in both groups; after MyoRing implantation for 8,45 D and MyoRing combined with CXL for 7,44 D, the spherical equivalent decreased for 7,72 and 6,29 D respectively, after 36 months. The cylinder decreased to 3,33 D with MyoRing alone and to 3,11 D with MyoRing combined with CXL. The smallest corneal thickness remained stable during 36 months after the procedure. There was an improvement in uncorrected and corrected visual acuity, and the difference in the CRF within the period of up to 12 months after the operation. It can be explained by the pseudochase formation in the group with a combined procedure. Conclusion. The implantation of the MyoRing IRC and the combination of MyoRing with CXL showed efficacy and safety in stabilizing keratoconus stabilization, as well as correction of comorbided ametropia 3 years after surgery. Both MyoRing implantation and MyoRing combined with CXL were effective in the stabilization of progressive keratoconus, as well as the correction of ametropia 3 years after surgery. There was no significant difference in MyoRing implantation and its combination with corneal crosslinking in visual and refractive results. The refractive power of the cornea was only one exeption. Long follow-up and randomized prospective studies with a large number of patients are needed.

Evaluation of changes in corneal biomechanics in eyes with keratectasia

2021 ◽  
pp. 179-187
Author(s):  
B.E. Malugin ◽  
◽  
E.G. Solodkova ◽  
S.V. Balalin ◽  
V.S. Kulikov ◽  
...  
Keyword(s):  
Corneal Thickness ◽  
Corneal Biomechanics ◽  
Corvis St ◽  
Collagen Crosslinking ◽  
The Third ◽  
Corneal Rigidity ◽  
Corneal Collagen Crosslinking ◽  
Early Features ◽  
Healthy Persons ◽  
Corneal Collagen

Purpose. To make a comparative analysis of topographic, tomographic and biomechanical values, measured by Pentacam HR and Corvis ST, in healthy multirefractive cohort versus patients with keratectasia of various severity. Material and methods. The prospective study comprised 237 patients aged from 18 to 47 years, subdivided into three groups. The first group included 174 healthy persons with various refraction (174 eyes). The second and the third group embraced 63 patients with keratoconus: 36 patients (36 eyes) with keratoconus of the I degree and 27 eyes with keratoconus of the II and III degrees. Besides the conventional comprehensive ocular examination the following studies were performed in all the patients: evaluation of topographic, tomographic and biomechanical corneal properties with application of Pentacam HR and Corvis ST (OCULUS Optikgerate GmbH; Wetzlar, Germany). Results. It was revealed that the following biomechanical values, assessed by means of Pentacam HR and Corvis ST, exhibited statistically significant changes (p<0,001) in all degrees of ketatoconus: a relative corneal thickness by Ambrosio, inverted radius of applanation curvature (IntRadius), DA Ratio Coefficient, values of corneal rigidity – SP-A 1 and SSI. Conclusion. The detected parameters may be applied as indicators, allowing to evaluate corneal biomechanics, to define early features of ectatic process, to assess effectiveness of the performed corneal collagen crosslinking and intralamellar keratoplasty with implantation of corneal segments. Key words: keratoconus, corneal biomechanics, pachymetry, index of pachymetric progression, corneal viscoelasticity.

scholarly journals Combined small-incision lenticule extraction and intrastromal corneal collagen crosslinking to treat mild keratoconus: Long-term follow-up

2015 ◽  
Vol 41 (11) ◽  
pp. 2524-2532 ◽  
Author(s):  
Enrique O. Graue-Hernandez ◽  
Gabriela L. Pagano ◽  
Guillermo Garcia-De la Rosa ◽  
Arturo Ramirez-Miranda ◽  
Jesus Cabral-Macias ◽  
...  
Keyword(s):  
Small Incision Lenticule Extraction ◽  
Collagen Crosslinking ◽  
Small Incision ◽  
Long Term Follow Up ◽  
Lenticule Extraction ◽  
Corneal Collagen Crosslinking ◽  
Corneal Collagen

scholarly journals Topographic outcomes after corneal collagen crosslinking in progressive keratoconus: 1-year follow-up

2017 ◽  
Vol 80 (2) ◽  
Author(s):  
Mauro C. Tiveron Jr. ◽  
Camila Ribeiro Koch Pena ◽  
Richard Yudi Hida ◽  
Luciane Bugmann Moreira ◽  
Felipe Roberto Exterhotter Branco ◽  
...  
Keyword(s):  
Collagen Crosslinking ◽  
Corneal Collagen Crosslinking ◽  
Corneal Collagen

scholarly journals Keratoconus in Children. Мodern Treatment Options

2021 ◽  
Vol 18 (4) ◽  
pp. 840-844
Author(s):  
E. Yu. Markova ◽  
G. V. Avakyants ◽  
E. V. Kechin
Keyword(s):  
Visual Acuity ◽  
Treatment Options ◽  
Corneal Thickness ◽  
High Tech ◽  
Cross Linking ◽  
Posterior Surface ◽  
Collagen Crosslinking ◽  
Optical Correction ◽  
Corneal Collagen Crosslinking ◽  
Corneal Collagen

Objective: to evaluate the results of corneal collagen crosslinking in children with keratoconus.Patients and methods. Since 2017, 125 children aged 4 to 17 years have been under observation, who have applied to the Eye Microsurgery named after Academician S.N. Fedorov with complaints of reduced visual acuity and, in some cases, the inability to select optical correction. All patients were examined, including using high-tech methods (Sheimpflug camera, OCT). Based on the anamnesis and the data obtained, the diagnosis of keratoconus stage I–III was made. Corneal collagen crosslinking was performed in 30 patients with stage II–III.Results. The study included 30 eyes of 30 patients (21 (68 %) boys, 9 (32 %) girls) with a median age — 16 (15; 17) years (12 to 17 years), who underwent accelerated “epi-off” crosslinking. No intra-and postoperative complications were observed. 12 months after CXL, there was a slowdown in the progression of keratoconus in children (minimum corneal thickness before surgery 460.00 (445.00; 477.00), after surgery 457.00 (441.00; 477.00), p = 0.112; K1 before surgery 44.60 (43.20; 46.90), after surgery 44.60 (42.90; 46.50), p = 0.481; K2 before surgery 48.30 (47.30; 51.25), after surgery 48.20 (47.21; 49.20), p = 0.779; elevation of the posterior surface before surgery 25.00 (18.00; 42.00), after surgery 26.00 (21.00; 42.00), p = 0.074, and increased visual acuity (NCOZ from 0.30 (0.05; 0.40) to 0.30 (0.20; 0.40) (p = 0.039) and MCOZ from 0.60 (0.40; 0.80) to 0.60 (0.50; 1.00) (p = 0.010)).Conclusion. 1. Keratoconus is also found in the child population. 2. Timely cross-linking of corneal collagen can slow the progression of keratoconus in children

Confocal biomicroscopic changes of the corneal layers following MyoRing implantation with corneal collagen crosslinking in keratoconus

2021 ◽  
pp. 21-25
Author(s):  
M.M. Bikbov ◽  
◽  
V.K. Surkova ◽  
G.М. Kazakbaeva ◽  
◽  
...  
Keyword(s):  
Confocal Microscopy ◽  
Morphological Changes ◽  
Corneal Crosslinking ◽  
Dynamic Observation ◽  
Transient Disturbances ◽  
Corneal Structure ◽  
Corneal Collagen Crosslinking ◽  
Corneal Ultrastructure ◽  
Corneal Collagen

Purpose. To study morphological changes in the cornea by confocal microscopy of simultaneous MyoRing implantation with corneal crosslinking in patients with keratoconus. Material and methods. The clinical study included 15 patients (16 eyes) with progressive keratoconus. All patients underwent a combination treatment: implantation of MyoRing intrastromal corneal rings (Dioptex GmBH, Linz, Austria) in combination with corneal crosslinking. The number of cells and quality indicators in each layer of the cornea were compared before and during 36 months after surgery. Results. Qualitative analysis of the cornea showed transient disturbances of the subepithelial nerve plexus, an increase in the reflectivity of stromal keratocytes, and moderate fibroplasia in the middle parts of the stroma in the area of the intrastromal pocket. During the follow-up period of 12 months or more after surgery, no significant changes in the corneal ultrastructure were detected in the dynamics. There was no significant decrease in endothelial cell density in the postoperative period. Conclusion. Analysis of morphological changes confirms the safety of a combination of simultaneous implantation of the MyoRing intrastromal ring and corneal crosslinking in stage II-III keratoconus by confocal microscopy and allows dynamic observation of changes in the corneal structure during intrastromal surgery. Key words: keratoconus, confocal microscopy, intrastromal corneal rings, MyoRing, corneal crosslinking.

Accelerated (9 mW/cm2) Corneal Collagen Crosslinking for Keratoconus—A 1-Year Follow-up

Cornea ◽  
2015 ◽  
Vol 34 (1) ◽  
pp. e1-e2 ◽  
Author(s):  
Uri Elbaz ◽  
Carl Shen ◽  
Alejandro Lichtinger ◽  
Noa Avni Zauberman ◽  
Yakov Goldich ◽  
...  
Keyword(s):  
Collagen Crosslinking ◽  
Corneal Collagen Crosslinking ◽  
Corneal Collagen

scholarly journals Impact of COVID-19 on keratoconus patients waiting for corneal cross linking

2021 ◽  
pp. 112067212110013
Author(s):  
Haider Shah ◽  
Luca Pagano ◽  
Anuj Vakharia ◽  
Giulia Coco ◽  
Kunal A Gadhvi ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Observational Study ◽  
Corneal Thickness ◽  
Treatment Delay ◽  
Cross Linking ◽  
Corneal Surface ◽  
Collagen Crosslinking ◽  
Time Period ◽  
Corneal Collagen Crosslinking ◽  
Corneal Collagen

Purpose: Royal College of Ophthalmologist recent guidance recommended delaying cross-linking services during the COVID-19 pandemic. This study investigates the effects of such delays in the delivery of cross-linking services in patients with keratoconus progression. Methods: Retrospective observational study of 46 patients with keratoconus progression, whose cross-linking was delayed due to the COVID-19 pandemic. Demographic and clinical details were obtained from assessments on the day of listing, and subsequent review on the day of the procedure. Topographic indices included keratometry of the posterior and anterior corneal surface, maximum keratometry ( Kmax), thinnest corneal thickness, ABCD progression and progression based on standard criteria recommendations (1.5 D Kmax & 20 microns thinning). Results: A total of 46 eyes were analysed with an average time between being listed for CXL and having the procedure done was 182 ± 65 days. The delay due to COVID-19 was of 3 months. In this time period they had a significant worsening of all keratometric indices and lost almost one line of visual acuity (0.19 ± 0.19 to 0.26 ± 0.18 LogMAR, p: 0.03). Thirty two eyes (70%) demonstrated progression in accordance with the ABCD progression criteria, while 18 eyes (39%) showed either an increase in Kmax of more than 1.5D or a thinning in corneal thickness of at least 20 μm. Conclusions: The treatment delay for the keratoconus patients caused further progression and vision worsening. We recommend that corneal collagen crosslinking needs to be considered as a high priority intervention.

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