title: Long-standing bullous keratopathy is associated with peripheral conjunctivalization and limbal deficiency.
abstract: OBJECTIVE
  To investigate whether peripheral corneal neovascularization in bullous keratopathy (BK) is due to conjunctivalization, a sign of limbal stem cell deficiency.
  
  
  METHODS
  Observational case-control study.
  
  
  METHODS
  Sixteen BK patients.
  
  
  METHODS
  Patients were divided into 2 groups: BK without peripheral neovascularization [NV(-) group; 5 patients, 5 eyes] and BK with neovascularization [NV(+) group; 11 patients, 13 eyes]. Evidence of conjunctivalization was evaluated by periodic acid-Schiff staining of impression cytology samples from the peripheral vascularized cornea. The 2 groups' durations of disease also were compared. Penetrating keratoplasty (PK) was performed in all 16 cases, and the 2 groups' durations of reepithelialization after PK were compared.
  
  
  METHODS
  Presence of goblet cells using impression cytology, duration of BK, and duration of postoperative reepithelialization.
  
  
  RESULTS
  Goblet cells were found on the peripheral corneal surface in all eyes in the NV(+) group. However, all eyes in the NV(-) group were negative for goblet cells (P<0.0001). Duration of disease was 14.4+/-5.4 months in the NV(-) group and 66.2+/-65.5 months in the NV(+) group (P = 0.030). Duration of postoperative epithelialization was 6.2+/-2.2 days in the NV(-) group and 28.8+/-36.5 days in the NV(+) group (P = 0.046).
  
  
  CONCLUSIONS
  Conjunctivalization of the peripheral cornea and delayed postoperative epithelialization in BK patients with NV suggest the presence of limbal stem cell deficiency in such patients. Patients with long-standing disease were found to be more prone to neovascularization. For this reason, early surgery may lead to a better surgical outcome.
authors.affiliation: Department of Ophthalmology, Tokyo Dental College, Chiba, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Uchino
authors.forename: Eiki
authors.initials: E
authors.lastname: Goto
authors.forename: Yoji
authors.initials: Y
authors.lastname: Takano
authors.forename: Murat
authors.initials: M
authors.lastname: Dogru
authors.forename: Naoshi
authors.initials: N
authors.lastname: Shinozaki
authors.forename: Shigeto
authors.initials: S
authors.lastname: Shimmura
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Yagi
authors.forename: Kazuo
authors.initials: K
authors.lastname: Tsubota
authors.forename: Jun
authors.initials: J
authors.lastname: Shimazaki
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D003228:Conjunctiva / Q000473:pathology*; D003316:Corneal Diseases / Q000175:diagnosis* / Q000601:surgery; D016510:Corneal Neovascularization / Q000175:diagnosis / Q000601:surgery; D003584:Cytological Techniques; D019573:Epithelium, Corneal / Q000473:pathology*; D005260:Female; D020397:Goblet Cells / Q000473:pathology; D006801:Humans; D015948:Keratoplasty, Penetrating; D016850:Limbus Corneae; D008297:Male; D008875:Middle Aged; D010503:Periodic Acid-Schiff Reaction; D012189:Retrospective Studies; D013234:Stem Cells / Q000473:pathology*