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 :
- P T Ashwin, P J McDonnell. Collagen cross-linkage: a comprehensive review and directions for future research. Br J Ophthalmol 2010;94:965e970.
- Wollensak G, Spoerl E, Seiler T. Riboflavin/ultraviolet-a-induced collagen crosslinking for the treatment of keratoconus. Am J Ophthalmol. 2003 May;135(5):620-7.
- Sorkin N, Varssano D. Corneal Collagen Crosslinking: A Systematic Review. OPH. 2014;232(1):10-27. doi:10.1159/000357979
- Subasinghe SK, Ogbuehi KC, Dias GJ. Current perspectives on corneal collagen crosslinking (CXL). Graefes Arch Clin Exp Ophthalmol. 2018;256(8):1363-1384. doi:10.1007/s00417-018-3966-0
- Xia Y, Chai X, Zhou C, Ren Q. Corneal nerve morphology and sensitivity changes after ultraviolet A/riboflavin treatment. Exp Eye Res. 2011;93(4):541–547.
- Spörl E, Huhle M, Kasper M, Seiler T. Artificial stiffening of the cornea by induction of intrastromal cross-links. Ophthalmologe. 1997;94(12):902–906.
- Randleman JB, Khandelwal SS, Hafezi F. Corneal cross-linking. Surv Ophthalmol. 2015;60(6):509-523. doi:10.1016/j.survophthal.2015.04.002.
- Grisevic S, Gilevska F, Biscevic A, Ahmedbegovic-Pjano M, Bohac M, Pidro A. Keratoconus Progression Classification One Year After Performed Crosslinking Method Based on ABCD Keratoconus Grading System. Acta Inform Med. 2020 Mar;28(1):18-23.
- Rabinowitz YS. Videokeratographic indices to aid in screening for keratoconus. J Refract Surg. 1995;11(5):371–379.
- Rabinowitz YS. Keratoconus. Surv Ophthalmol. 1998 Jan-Feb;42(4):297-319.
- Meek KM, Tuft SJ, Huang Y, Gill PS, Hayes S, Newton RH, Bron AJ. Changes in collagen orientation and distribution in keratoconus corneas. Invest Ophthalmol Vis Sci. 2005;46(6):1948–1956.
- Wollensak G, Spoerl E, Seiler T. Stress-strain measurements of human and porcine corneas after riboflavin ultraviolet- A-induced cross-linking. J Cataract Refract Surg. 2003;29(9):1780–1785.
- Kohlhaas M, Spoerl E, Schilde T, Unger G, Wittig C, Pillunat LE. Biomechanical evidence of the distribution of cross-links in corneas treated with riboflavin and ultraviolet A light. J Cataract Refract Surg. 2006;32(2):279–283.
- Chatzis N, Hafezi F. Progression of keratoconus and efficacy of pediatric corneal collagen cross-linking in children and adolescents. J Refract Surg. 2012;28(11):753–758.
- Kymionis GD, Kontadakis GA, Kounis GA, Portaliou DM, Karavitaki AE, Magarakis M, Yoo S, Pallikaris IG. Simultaneous topography-guided PRK followed by corneal collagen cross-linking for keratoconus. J Refract Surg. 2009;25(9):S807–S811.
- Alhayek A, Lu PR. Corneal collagen crosslinking in keratoconus and other eye disease. Int J Ophthalmol. 2015 Apr 18;8(2):407-18. doi: 10.3980/j.issn.2222-3959.2015.02.35. PMID: 25938065; PMCID: PMC4413599.
- Pollhammer M, Cursiefen C. Bacterial keratitis early after corneal crosslinking with riboflavin and ultraviolet-A. J Cataract Refract Surg. 2009;35(3):588–589.
- Raiskup F, Hoyer A, Spoerl E. Permanent corneal haze after riboflavin-UVA-induced cross-linking in keratoconus. J Refract Surg. 2009;25(9):S824–S828.
- Wollensak G, Spoerl E, Wilsch M, Seiler T. Endothelial cell damage after riboflavin-ultraviolet-A treatment in the rabbit. J Cataract Refract Surg. 2003;29(9):1786–1790.
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.