Corneal Collagen Crosslinking: An Observational Study in a Tertiary Eye Hospital in Bangladesh


Authors : Dr. Sujit Kumar Biswas; Dr. Soma Rani Roy; Dr. Abdul Matin Bhuiyan; Nasrin Akter; Dr. Zubaida Noor; Tangila Mohona

Volume/Issue : Volume 9 - 2024, Issue 12 - December

Google Scholar : https://tinyurl.com/ycyvd2u5

Scribd : https://tinyurl.com/ymy35ubj

DOI : https://doi.org/10.5281/zenodo.14598591

Abstract : Aim: To observe the result of corneal collagen crosslinking in keratoconus patients in a tertiary eye hospital in Bangladesh.  Material and Methods: Fifty-two eyes of 37 patients received collagen crosslinking therapy over a period of 2 years. Patient with keratoconus under the age of thirty, clear cornea with a thickness more than 400 micron were cross-linked with “epi-off” procedure. Corneal thickness < 400 μ, corneal scar, active VKC, history of previous herpes viral diseases were excluded. All patients were assessed by pentacam topography. Collagen cross-linking was done under topical, peribulbar block or general anesthesia depending on the age and co-operation of the patients. Central corneal epithelium measuring 8-9 mm of was detached with the help 70% ethyl alcohol. 0.1% riboflavin solution was applied over the cornea for 60 minutes with every 2 minutes interval and UV-A (370nm) irradiance last 30 minutes. Corneal surface cleaned with Hartmann’s solution, bandage contact lens was applied and installed broad spectrum antibiotic and then pad and bandage. Post operatively patient was treated with topical cycloplegic, antibiotic and corticosteroid. Regular follow up at day 7, one month, 3 months and 6 months were taken. Every follow up, visual assessment, intraocular pressure measurement measurement was done by air puff tonometer. After 6 months, pentacam topography was done in treated eyes and compared with the pre-CXL topography to assess the changes. All data regarding age, gender, stage, visual acuity, K-Max, astigmatism, Q-value, CCT, CTI, thinnest pachymetry were recorded pre- and post- operatively and analyzed by using SPSS-16 software.  Result: There were total 52 eyes of 37 patients and the male female ratio was 1.5: 1. Mean age was 19.73+4.30 years (range 11 to 28 years). It was observed that 96 % (n-50) patient’s progression was stopped. 17% patients improve to subclinical level after CXL, which is statistically significant. Corneal diopter-power (K-Max) became reduced to a significant level. Change of astigmatism did not show statistically significant. Corneal asphericity expressed by ‘Q’-value, central corneal thickness (CCT), thinnest pachymetry of cornea and corneal thickness index (CTI) all reduced to a statistically significant levels. Although the central corneal thickness reduced but looks stronger shown by reducing the curvature.Good visual acuity (6/6-6/18) was achieved in 58% patients, where as poor vision reduced to 2% from 21%. There was no significant complications except one patient develop rounded corneal scar along the base of the cone.  Conclusion: Corneal collagen crosslinking therapy halted the progression of keratoconus effectively and improved clinical outcome.

Keywords : Keratoconus, Corneal Collagen Crosslinking (CXL), Riboflavin, UVA-370, Pentacam Topography.

References :

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Aim: To observe the result of corneal collagen crosslinking in keratoconus patients in a tertiary eye hospital in Bangladesh.  Material and Methods: Fifty-two eyes of 37 patients received collagen crosslinking therapy over a period of 2 years. Patient with keratoconus under the age of thirty, clear cornea with a thickness more than 400 micron were cross-linked with “epi-off” procedure. Corneal thickness < 400 μ, corneal scar, active VKC, history of previous herpes viral diseases were excluded. All patients were assessed by pentacam topography. Collagen cross-linking was done under topical, peribulbar block or general anesthesia depending on the age and co-operation of the patients. Central corneal epithelium measuring 8-9 mm of was detached with the help 70% ethyl alcohol. 0.1% riboflavin solution was applied over the cornea for 60 minutes with every 2 minutes interval and UV-A (370nm) irradiance last 30 minutes. Corneal surface cleaned with Hartmann’s solution, bandage contact lens was applied and installed broad spectrum antibiotic and then pad and bandage. Post operatively patient was treated with topical cycloplegic, antibiotic and corticosteroid. Regular follow up at day 7, one month, 3 months and 6 months were taken. Every follow up, visual assessment, intraocular pressure measurement measurement was done by air puff tonometer. After 6 months, pentacam topography was done in treated eyes and compared with the pre-CXL topography to assess the changes. All data regarding age, gender, stage, visual acuity, K-Max, astigmatism, Q-value, CCT, CTI, thinnest pachymetry were recorded pre- and post- operatively and analyzed by using SPSS-16 software.  Result: There were total 52 eyes of 37 patients and the male female ratio was 1.5: 1. Mean age was 19.73+4.30 years (range 11 to 28 years). It was observed that 96 % (n-50) patient’s progression was stopped. 17% patients improve to subclinical level after CXL, which is statistically significant. Corneal diopter-power (K-Max) became reduced to a significant level. Change of astigmatism did not show statistically significant. Corneal asphericity expressed by ‘Q’-value, central corneal thickness (CCT), thinnest pachymetry of cornea and corneal thickness index (CTI) all reduced to a statistically significant levels. Although the central corneal thickness reduced but looks stronger shown by reducing the curvature.Good visual acuity (6/6-6/18) was achieved in 58% patients, where as poor vision reduced to 2% from 21%. There was no significant complications except one patient develop rounded corneal scar along the base of the cone.  Conclusion: Corneal collagen crosslinking therapy halted the progression of keratoconus effectively and improved clinical outcome.

Keywords : Keratoconus, Corneal Collagen Crosslinking (CXL), Riboflavin, UVA-370, Pentacam Topography.

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