title: In vivo confocal evaluation of the ocular surface morpho-functional unit in dry eye.
abstract: OBJECTIVE
  To study, by a new, integrated, laser scanning confocal microscopy approach, the ocular surface morpho-functional unit in patients with primary Sjogren syndrome (SSI), non-Sjogren syndrome dry eye (non-SSDE), and meibomian gland disease (MGD).
  
  
  METHODS
  Patients and age- and sex-matched control subjects (N = 60; 15 each) were consecutively enrolled in a prospective case-control study. Laser scanning confocal microscopy was used to obtain simultaneous optical sampling of the ocular surface components: cornea, bulbar and tarsal conjunctiva, MGs, and eyelid margin.
  
  
  RESULTS
  For all superficial epithelia, except eyelid margins, there were reduced cell densities in each group compared with that in controls (p < 0.001). The lowest cell densities were in the SSI group (p < 0.001). Eyelid margin superficial cell density was decreased only in MGD (p < 0.001). Basal epithelial cell density at the corneal apex was increased in both SSI and non-SSDE compared with that in controls (p < 0.01). In the conjunctiva, it was decreased in each group compared with that in controls (p < 0.01). Subbasal dendritic cell density was significantly increased in both SSI and MGD compared with that in controls (p < 0.01). Conjunctival inflammatory cell density and MG inflammation were increased in each group compared with those in controls (p < 0.001), with the highest values in SSI. Subbasal nerve plexi had fewer fibers and higher bead density in each group compared with those in controls (p < 0.001). There was increased tortuosity in both SSI and MGD (p < 0.001). Patients with MGD had the lowest MG acinar density, the largest diameter of acini and acinar orifices, and the highest secretion reflectivity (p < 0.001).
  
  
  CONCLUSIONS
  Laser scanning confocal microscopy can provide an in vivo, noninvasive, high-resolution overview of the ocular surface morpho-functional unit. This confocal integrated approach may be useful in both research and clinical settings.
authors.affiliation: Università degli Studi di Milano, UO Oculistica Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milan, Italy. eddy.villani@tiscali.it
authors.forename: Edoardo
authors.initials: E
authors.lastname: Villani
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Magnani
authors.forename: Francesco
authors.initials: F
authors.lastname: Viola
authors.forename: Alessandro
authors.initials: A
authors.lastname: Santaniello
authors.forename: Raffaella
authors.initials: R
authors.lastname: Scorza
authors.forename: Paolo
authors.initials: P
authors.lastname: Nucci
authors.forename: Roberto
authors.initials: R
authors.lastname: Ratiglia
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D002452:Cell Count; D003228:Conjunctiva / Q000473:pathology*; D015352:Dry Eye Syndromes / Q000473:pathology*; D004847:Epithelial Cells / Q000473:pathology; D019573:Epithelium, Corneal / Q000473:pathology*; D005143:Eyelids / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D018613:Microscopy, Confocal; D008875:Middle Aged; D011446:Prospective Studies; D055815:Young Adult