Louisa M Bulirsch1,2, Constance Weber1, Marlene Saßmannshausen1, Markus Kohlhaas3, Frank G Holz1, Karin U Loeffler1,2, Martina C Herwig-Carl4,5. 1. Augenklinik, Universitätsklinikum Bonn, Ernst-Abbe-Str. 2, 53127, Bonn, Deutschland. 2. Sektion Ophthalmopathologie, Universitäts-Augenklinik Bonn, Ernst-Abbe-Str. 2, 53127, Bonn, Deutschland. 3. Klinik für Augenheilkunde, St.-Johannes-Hospital, Johannesstr. 9-17, 44137, Dortmund, Deutschland. 4. Augenklinik, Universitätsklinikum Bonn, Ernst-Abbe-Str. 2, 53127, Bonn, Deutschland. martina.herwig-carl@ukbonn.de. 5. Sektion Ophthalmopathologie, Universitäts-Augenklinik Bonn, Ernst-Abbe-Str. 2, 53127, Bonn, Deutschland. martina.herwig-carl@ukbonn.de.
Abstract
BACKGROUND: Keratoconus is classified as a corneal ectasia and is a multifactorial disease. In those affected, mostly adolescent patients visual deterioration occurs due to the development of irregular astigmatism. Treatment by corneal cross-linking (CXL) has been indicated in progressive disease for several years. OBJECTIVE: To present the pathophysiology and histological changes in keratoconus as well as wound healing processes after CXL and their potential complications. MATERIAL AND METHODS: Histological changes in keratoconus as well as wound healing processes after CXL and their potential complications are presented based on histological examination of corneal specimens with keratoconus with and without a condition after CXL. Relevant literature and own data are analyzed and discussed. RESULTS: Besides inflammatory processes, atopic and genetic dispositions play a role in the development of keratoconus. The histological characteristics of keratoconus include changes in the epithelium, Bowman's layer and stroma. Wound healing processes after CXL include healing of the surface epithelium and transient loss of keratocytes and nerve fibers. CONCLUSION: Keratoconus shows characteristic histopathological changes, such as epithelial irregularities, stromal thinning and breaks of Bowman's layer, whereas the endothelium and Descemet's membrane remain unchanged (apart from cases of corneal hydrops). After CXL wound healing processes can be followed primarily in vivo by confocal microscopy. Complications after CXL are rare. Persistent loss of keratocytes can be clinically manifested as a visually relevant scar.
BACKGROUND: Keratoconus is classified as a corneal ectasia and is a multifactorial disease. In those affected, mostly adolescent patients visual deterioration occurs due to the development of irregular astigmatism. Treatment by corneal cross-linking (CXL) has been indicated in progressive disease for several years. OBJECTIVE: To present the pathophysiology and histological changes in keratoconus as well as wound healing processes after CXL and their potential complications. MATERIAL AND METHODS: Histological changes in keratoconus as well as wound healing processes after CXL and their potential complications are presented based on histological examination of corneal specimens with keratoconus with and without a condition after CXL. Relevant literature and own data are analyzed and discussed. RESULTS: Besides inflammatory processes, atopic and genetic dispositions play a role in the development of keratoconus. The histological characteristics of keratoconus include changes in the epithelium, Bowman's layer and stroma. Wound healing processes after CXL include healing of the surface epithelium and transient loss of keratocytes and nerve fibers. CONCLUSION: Keratoconus shows characteristic histopathological changes, such as epithelial irregularities, stromal thinning and breaks of Bowman's layer, whereas the endothelium and Descemet's membrane remain unchanged (apart from cases of corneal hydrops). After CXL wound healing processes can be followed primarily in vivo by confocal microscopy. Complications after CXL are rare. Persistent loss of keratocytes can be clinically manifested as a visually relevant scar.
Authors: Jayne S Weiss; Hans Ulrik Møller; Anthony J Aldave; Berthold Seitz; Cecilie Bredrup; Tero Kivelä; Francis L Munier; Christopher J Rapuano; Kanwal K Nischal; Eung Kweon Kim; John Sutphin; Massimo Busin; Antoine Labbé; Kenneth R Kenyon; Shigeru Kinoshita; Walter Lisch Journal: Cornea Date: 2015-02 Impact factor: 2.651
Authors: Louisa M Bulirsch; Constance Weber; Marlene Saßmannshausen; Markus Kohlhaas; Frank G Holz; Karin U Loeffler; Martina C Herwig-Carl Journal: Ophthalmologe Date: 2021-12-07 Impact factor: 1.059