title: [Evaluation of conjunctival epithelium of filtering blebs by impression cytology].
abstract: OBJECTIVE
  To study the ocular surface in filtering blebs using impression cytology, comparing the bleb side and areas outside the bleb edges.
  
  
  METHODS
  Twelve filtering blebs of 8 patients were included: 4 cases of trabeculectomy without mitomycin C (MMC), 6 cases of trabeculectomy with MMC, and 2 cases of non-penetrating glaucoma surgery. Impression cytology specimens were taken from filtering blebs as well as outside the bleb area. A classification scale from 0 to 3 was used to describe the distribution of epithelial cells and the density of goblet cells. Grade 0 indicated cohesive epithelial cells and abundant goblet cells; and the grade 3 indicated loss of epithelial cohesion and absence of goblet cells.
  
  
  RESULTS
  The mean grade of cytology in filtering blebs was 2.4 ± 0.9, and in the outside bleb area of 0.8 ± 0.3 (P<.001). These differences were independent of the use of MMC (P=.48). The large majority (83%) of filtering blebs showed a decrease in epithelial cohesion and absence of goblet cells. Outside the bleb area, 100% of the cases had cohesive epithelial cells with different grades of goblet cells.
  
  
  CONCLUSIONS
  The conjunctival epithelium overlying the filtering blebs showed significant changes that consisted of increased intercellular spaces and loss of goblet cells. These increased intercellular spaces could explain the trans-epithelial pathway of aqueous humor. The least amount of mucin due to loss of goblet cells could contribute to increase the risk of infection in filtering blebs.
authors.affiliation: Departamento de Oftalmología, Hospital Universitari Arnau de Vilanova, Lérida, España; Institut de Recerca Biomèdica de Lleida (IRB Lleida), Lérida, España. Electronic address: mariajesus.muniesa@gmail.com.
authors.forename: M J
authors.initials: MJ
authors.lastname: Muniesa
authors.affiliation: Institut de Recerca Biomèdica de Lleida (IRB Lleida), Lérida, España; Departamento de Patología y Genética Molecular, Hospital Universitari Arnau de Vilanova, Lérida, España.
authors.forename: S
authors.initials: S
authors.lastname: González
authors.affiliation: Institut de Recerca Biomèdica de Lleida (IRB Lleida), Lérida, España; Departamento de Patología y Genética Molecular, Hospital Universitari Arnau de Vilanova, Lérida, España.
authors.forename: P
authors.initials: P
authors.lastname: Buetas
authors.affiliation: Institut de Recerca Biomèdica de Lleida (IRB Lleida), Lérida, España; Departamento de Patología y Genética Molecular, Hospital Universitari Arnau de Vilanova, Lérida, España.
authors.forename: S
authors.initials: S
authors.lastname: López
authors.affiliation: Departamento de Oftalmología, Hospital Universitari Arnau de Vilanova, Lérida, España; Institut de Recerca Biomèdica de Lleida (IRB Lleida), Lérida, España.
authors.forename: C
authors.initials: C
authors.lastname: Sánchez
authors.affiliation: Institut de Recerca Biomèdica de Lleida (IRB Lleida), Lérida, España; Departamento de Patología y Genética Molecular, Hospital Universitari Arnau de Vilanova, Lérida, España.
authors.forename: X
authors.initials: X
authors.lastname: Matias-Guiu
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001082:Aqueous Humor / Q000502:physiology; D001768:Blister / Q000209:etiology / Q000473:pathology*; D003229:Conjunctival Diseases / Q000209:etiology / Q000473:pathology*; D003231:Conjunctivitis / Q000453:epidemiology / Q000209:etiology; D003584:Cytological Techniques; D004847:Epithelial Cells / Q000473:pathology; D004848:Epithelium / Q000187:drug effects / Q000473:pathology*; D005260:Female; D018463:Filtering Surgery; D005902:Glaucoma, Open-Angle / Q000601:surgery*; D020397:Goblet Cells / Q000473:pathology; D006801:Humans; D008297:Male; D016685:Mitomycin / Q000494:pharmacology / Q000627:therapeutic use; D011183:Postoperative Complications / Q000209:etiology / Q000473:pathology*; D012306:Risk; D014130:Trabeculectomy
chemical_list: D016685:Mitomycin
keywords: Ampollas filtrantes; Citogía de impresión conjuntival; Conjunctival impression cytology; Filtering bleb; Glaucoma; Ocular surface; Superficie ocular