Loscos-Arenas Jordi1*, Tapia Gustavo2, Moll-Udina Aina1, Romanic Nevena1 and Romera Pau1
1Department of Ophthalmology, Hospital Universitari Germans Trias i Pujol, Universitat Autonoma de Barcelona, Carretera de Canyet s/n, 08916 Badalona, Barcelona, Spain
2Department of Pathology, Hospital Universitari Germans Trias i Pujol, Universitat Autonoma de Barcelona, Carretera de Canyet s/n, 08916 Badalona, Barcelona, Spain
Received: 19 December, 2016; Accepted: 03 April, 2017; Published: 04 April, 2017
Loscos-Arenas Jordi, Hospital Universitari Germans Trias i Pujol, Department of Ophthalmology, Carretera de Canyet s/n, 08916 Badalona, Barcelona, Telephone: +34.93.465.12.00.00; E-mail:
Jordi LA, Gustavo T, Aina MU, Nevena R, Pau R (2017) Conjunctival Leaking Bleb after Cross-Linking using Riboflavin and UVA: A Histopathological Study. J Clin Res Ophthalmol 4(1): 022-004. 10.17352/2455-1414.000039
© 2017 Jordi LA, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Cystic bleb; Collagen crosslinking; Riboflavin; Ki67 antibody
Two conjunctival leaking blebs were excisioned to assess by histological methods the cellular effect after corneal cross-linking treatment. Sections were stained with hematoxylin-eosin and immunohistochemistry with the Ki67 antibody. The proliferating marker Ki67 was detected only in both treated pieces with a very significant increase in epithelial proliferating cells in one case but not in the other. Further studies are necessary to continue understanding the response to treatment of the ischemic blebs with CXL and riboflavin.
Corneal collagen crosslinking (CXL), using ultraviolet-A (UVA) radiation and riboflavin, it is a non-invasive treatment of progressive keratoconus. As the procedure has shown a positive effect on the biomechanical of the cornea it could be a real alternative for late-onset bleb leakage in certain cases. Recent published studies [1,2], show encouraging results with this simple and non-invasive technique. Although in both series only one eye had a significant intraocular pressure (IOP) increase in the first set and two in the second, almost in all treated eyes the seidel test were normalized, which would support the postulate that CXL reinforces residual collagen bonding. However, in most of the eyes a slight IOP increase was observed and it is hardly attributable to the treatment because these eyes have a self-resolving tendency with a self-limiting seidel phenomena with fluctuating visual acuity.
Materials and Methods
To assess the cellular effect in the conjunctival leaking cystic blebs after corneal cross-linking treatment we have excisioned two cystic conjunctival blebs treated with MMC (0.02 mgr/mL for 2 minutes) of two eyes with a previous history of glaucoma surgery. The subjects gave their informed consent for the study. After excision, one piece of both ischemic tissues was treated with CXL and Riboflavin ex-vivo, keeping the other piece as a control. One Riboflavin drop (0.1% without dextran, Mediocross©M) was applied every 2 min for 20 minutes, followed by UVA irradiation 9 mW/cm2 - 10 minutes (CCL VarioSystem, Ophtec®). Samples were then fixed in formalin and embedded in paraffin, and sequential sections were stained with hematoxylin-eosin and immunohistochemistry with the Ki67 antibody.
The hematoxylin-eosin (H&E) study did not show any significant difference between the treated piece with CXL and riboflavin and the untreated piece (Figure 1). The proliferating marker Ki67 was detected only in both treated pieces with a very significant increase in epithelial proliferating cells in one case but not in the other (Figure 2).
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