Polymers in Medicine

Polim. Med.
Scopus CiteScore: 3.5 (CiteScore Tracker 3.6)
Index Copernicus (ICV 2023) – 121.14
MEiN – 70
ISSN 0370-0747 (print)
ISSN 2451-2699 (online) 
Periodicity – biannual

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Polymers in Medicine

2016, vol. 46, nr 1, January-June, p. 89–94

doi: 10.17219/pim/65010

Publication type: review article

Language: English

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Creative Commons BY-NC-ND 3.0 Open Access

Corneal Cross-Linking: An Example of Photoinduced Polymerization as a Treatment Modality in Keratoconus

Magdalena Kubrak-Kisza1,A,B,C,D, Krystian Jerzy Kisza1,B,C, Marta Misiuk-Hojło1,A,F

1 Department and Clinic of Ophthalmology, Wroclaw Medical University, Wroclaw, Poland

Abstract

The cornea is one of the principal refractive elements in the human eye and plays a crucial role in the process of vision. Keratoconus is the most common corneal dystrophy, found mostly among young adults. It is characterized by a reduced number of collagen cross-links in the corneal stroma, resulting in reduced biomechanical stability and an abnormal shape of the cornea. These changes lead to progressive myopia, corneal thinning, central scarring and irregular astigmatism, causing severely impaired vision. Hard contact lenses, photorefractive keratectomy or intracorneal rings are the most common treatment options for refractive error caused by keratoconus. However, these techniques do not treat the underlying cause of the corneal ectasia and therefore are not able to stop the progression of the disease. Riboflavin photoinduced polymerization of corneal collagen, also known as corneal cross-linking (CXL), has been introduced as the first therapy which, by stabilizing the structure of the cornea, prevents the progression of keratoconus. It stiffens the cornea using the photo-sensitizer riboflavin in combination with ultraviolet irradiation. This is a current review of the CXL procedure as a therapy for keratoconus, which relies on photoinduced polymerization of human tissue. We have focused on its biomechanical and physiological influences on the human cornea and have reviewed the previous and current biochemical theories behind cross-linking reactions in the cornea.

Key words

cornea, keratoconus, polymerization, cross-linking

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