Comparison of Changes in Central Corneal Thickness During Corneal Collagen Cross-Linking, Using Isotonic Riboflavin Solutions With and Without Dextran, in the Treatment of Progressive Keratoconus

Zaheer, Naima; Khan, W. A.; Khan, Shahtaj; Khan, Munira

doi:10.1097/ico.0000000000001496

Cited by 26 publications

(30 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…A previous study reported a decrease in corneal thickness of 12.1% with dextran riboflavin (30 min) and a 26.1% increase pachymetry using 1.1% HPMC riboflavin (for 20 min). 23 The saturation time of riboflavin in HPMC for 20 min in the study cited above may be the cause of the most significant increase in corneal thickness when compared to our study. Kymionis et al 24 reported a 20% thickness reduction using dextran riboflavin within 30 min.…”

Section: Dovepresssupporting

confidence: 44%

<p>Comparative Two-Photon Fluorescence Microscopy Analysis of Riboflavin Penetration in Two Different Solutions: Dextran and Hydroxypropyl Methylcellulose</p>

Paula¹,

Cresta²,

Alves³

2020

OPTH

View full text Add to dashboard Cite

This study compared riboflavin penetration in porcine corneas using two different solutions: dextran and hydroxypropyl methylcellulose (HPMC). Methods: Porcine corneas were de-swollen and after prepared in an artificial anterior chamber with balanced saline solution. The pressure was checked with a portable tonometer. We used 0.1% riboflavin in 20% dextran for 30 min or 0.1% riboflavin in 1% HPMC for 10 min. The fluorescence intensity in multiphoton microscopy was used to evaluate concentration into the cornea, and ultrasonic pachymetry was performed before and after using riboflavin. Results: Riboflavin concentration up to 340 μm was higher in the HPMC group (p 0.146). From 340 microns to 500 μm, the concentration was higher in the dextran group (p 0.248). There was no statistically significant difference between the groups when considering all the corneal thickness studied (p 0.528). Pachymetric measurements in the group with dextran showed a 12.9% corneal thickness decrease after 30 min, while the HPMC group showed a 9.1% increase after 10 min. Conclusion: We concluded that 1% HPMC riboflavin for 10 min had the same level of safety when compared to the Dresden protocol with dextran riboflavin for 30 min. Ultrasonic pachymetry during corneal crosslinking has fundamental importance in controlling corneal hydration due to changes in thickness caused by different types of riboflavin. This study used different methods than previous studies to better simulate corneal physiological conditions and used 1% HPMC concentration which differs from previous studies performed with 1.1% HPMC.

show abstract

Section: Dovepresssupporting

confidence: 44%

<p>Comparative Two-Photon Fluorescence Microscopy Analysis of Riboflavin Penetration in Two Different Solutions: Dextran and Hydroxypropyl Methylcellulose</p>

Paula¹,

Cresta²,

Alves³

2020

OPTH

View full text Add to dashboard Cite

show abstract

“…; Zaheer et al. ). Therefore, we changed our CXL protocol to 0.1% riboflavin with methylcellulose as the main supplement (methylcellulose–riboflavin) in 2012.…”

Section: Introductionmentioning

confidence: 97%

“…In addition, the use of hypotonic riboflavin is timeconsuming and adds an extra cost to the procedure. Using methylcellulose rather than dextran in the riboflavin solution has the advantage of increasing intraoperative central corneal thickness (CCT) during CXL (Oltulu et al 2014;Zaheer et al 2018). Therefore, we changed our CXL protocol to 0.1% riboflavin with methylcellulose as the main supplement (methylcelluloseriboflavin) in 2012.…”

Section: Introductionmentioning

confidence: 99%

Superior outcome of corneal collagen cross‐linking using riboflavin with methylcellulose than riboflavin with dextran as the main supplement

Thorsrud

Hagem

Sandvik

et al. 2018

Acta Ophthalmologica

View full text Add to dashboard Cite

Purpose To compare the effect of corneal collagen cross‐linking (CXL) on progressive keratoconus using 0.1% riboflavin with either dextran or methylcellulose as the main supplement. Methods In a comparative case series, CXL was performed in 40 patients (40 eyes) using a riboflavin solution containing either dextran (dextran–riboflavin; n = 20) or methylcellulose (methylcellulose–riboflavin; n = 20). Changes in central corneal thickness (CCT), Scheimpflug tomography, maximal keratometry reading (Kmax), visual acuity (VA) and endothelial cell density (ECD) were recorded. Stromal changes one month after surgery were analysed using optical coherence tomography (OCT) and in vivo confocal microscopy (IVCM). Results The CCT was significantly higher in the methylcellulose–riboflavin group during the CXL procedure. The IVCM demarcation line depth was 274 ± 80 (SD) μm in the dextran–riboflavin group and 442 ± 80 μm in the methylcellulose–riboflavin group (p < 0.001). Complete absence of keratocytes in the pre‐endothelial stroma was found in none of the corneas treated with dextran–riboflavin and in 42% of the corneas treated with methylcellulose–riboflavin. Visibility of the OCT demarcation line was significantly lower in the methylcellulose–riboflavin group. Kmax and corrected distance visual acuity were improved in the methylcellulose–riboflavin group and stable in the dextran–riboflavin group after 2 years. Endothelial cell density (ECD) was stable in both groups. Conclusion We found deeper structural changes in the methylcellulose–riboflavin group than in the dextran–riboflavin group. This may be explained by different riboflavin solution properties and raises safety concerns. The study also indicates improved effect using methylcellulose–riboflavin than dextran–riboflavin, possibly explained by deeper stromal CXL effect.

show abstract

“…Ribo avin and Ultraviolet-A are used in cross-linking therapy [19]. Purpose in corneal cross linking; It is aimed to increase the number of cross-links in the cornea, biomechanical strength, increase in collagen ber diameter, increase in shrinkage temperature, increase enzymatic resistance, and increase resistance to edema [20,21]. At the same time corneal cross-linking and anti-collagenase effect, anterior and middle Apoptosis of keratocytes in the stroma and deep keratocytes in their follow-upit makes it reproduce again [22].…”

Section: Discussionmentioning

confidence: 99%

Decreased Central and Limbal Epithelium Thickness After Corneal Crosslinking Evaluated by Anterior Segment Optic Coherence Tomography

Güçlü

Akaray

Kaya

2021

Preprint

View full text Add to dashboard Cite

Aim: To Investigate the central cornea, limbal epithelium thickness and stroma thickness after corneal cross-linking by Anterior Segment Optical Coherence Tomography (AS-OCT) and Scheimpflug topography.Methods: Fifteen keratoconus patients treated with cross-linking(CXL) and fifteen untreated keratoconus patients was included to the study. Corneal central, limbal epithelial, stromal and total thickness with was analyzed by using Anterior Segment Optical Coherence Topography (AS-OCT) and keratometric values were analyzed by Scheimpflug topography.Results: There was a statisticallly significant difference between treated and untreated keratoconus patients according to limbal epithelial thickness (LET). Limbal epithelial thickness was 30.7 ± 5.5µm in the treated keratoconus patients and 45.6 ± 11.5µm in the untreated patients (p = 0.04). Central corneal epithelial thickness (CCET) was 38.27±3.5 in the treated group and 60.8 ± 10.9µm in the untreated group. There was a statistically signifficant difference the between two groups (p=0.01). The posterior astigmatism value was 0.7 ± 0.3D in the treated group and 0.9 ± 0.5D in untreated group by Scheimpflug topography (p=0.03).Conclusion: Our study have shown that the central corneal epithelium and limbal epithelium were significantly thinned as a result of corneal cross-linking. Corneal posterior astigmatism value decreased among the keratometric values. Epithelial thickness and limbal thickness alterations detected with Ant-OCT could be useful for monitorizing the keratoconus patients treated with crosslinking and could show the effectivity of the treatment.

show abstract

Comparison of Changes in Central Corneal Thickness During Corneal Collagen Cross-Linking, Using Isotonic Riboflavin Solutions With and Without Dextran, in the Treatment of Progressive Keratoconus

Abstract: During cross-linking, isotonic riboflavin with dextran causes a significant decrease in corneal thickness, whereas dextran-free isotonic riboflavin causes a significant increase in corneal thickness, thus facilitating the procedure.

Cited by 26 publications

References 31 publications

<p>Comparative Two-Photon Fluorescence Microscopy Analysis of Riboflavin Penetration in Two Different Solutions: Dextran and Hydroxypropyl Methylcellulose</p>

<p>Comparative Two-Photon Fluorescence Microscopy Analysis of Riboflavin Penetration in Two Different Solutions: Dextran and Hydroxypropyl Methylcellulose</p>

Superior outcome of corneal collagen cross‐linking using riboflavin with methylcellulose than riboflavin with dextran as the main supplement

Decreased Central and Limbal Epithelium Thickness After Corneal Crosslinking Evaluated by Anterior Segment Optic Coherence Tomography

Contact Info

Product

Resources

About