title: Corneal changes after a single session of selective laser trabeculoplasty for open-angle glaucoma.
abstract: OBJECTIVE
  To investigate the changes in endothelial cell count, central corneal thickness (CCT), and refractive error after a session of selective laser trabeculoplasty (SLT) for open angle glaucoma (OAG).
  
  
  METHODS
  This prospective cohort study recruited 111 eyes of 66 consecutive subjects with OAG. Subjects received SLT to 360° of the trabecular meshwork. Endothelial cell count, CCT, and spherical equivalent were measured at baseline before SLT as well as at 1 week and 1 month post SLT. A repeated measure nested ANOVA with Tukey's multiple comparison test was performed to compare the outcome measures before and after SLT.
  
  
  RESULTS
  In 111 eyes of 66 subjects, the mean number of laser applications per treatment was 166.9 ± 41.4 with a mean energy level of 1.0 ± 0.07 mJ. The mean endothelial cell count decreased significantly from 2465.0 ± 334.0 cells/mm(2) at baseline to 2355.0 ± 387.0 cells/mm(2) at 1 week (P=0.0004) but increased to baseline levels at 1 month post SLT (2424.0 ± 379.4 cells/mm(2), P=0.3). The CCT, which decreased from a baseline of 549.4 ± 37.6 to 543.9 ± 40.2 μm at 1 week post SLT (P=0.02), also returned to the baseline level by 1 month (P=0.2). The spherical equivalent was static from baseline. A positive correlation was found between total laser energy and CCT at 1 month post treatment (r=0.3, P=0.005).
  
  
  CONCLUSIONS
  The transient reductions in endothelial cell count and CCT following SLT returned to baseline levels 1 month after the procedure. Patients undergoing SLT should be aware of the risk of potential corneal changes.
authors.affiliation: Department of Ophthalmology, University of Hong Kong, Hong Kong, People's Republic of China.
authors.forename: J W Y
authors.initials: JW
authors.lastname: Lee
authors.affiliation: Department of Ophthalmology, Queen Mary Hospital, Hong Kong, People's Republic of China.
authors.forename: J C H
authors.initials: JC
authors.lastname: Chan
authors.affiliation: Byers Eye Institute, Stanford University, Palo Alto, CA, USA.
authors.forename: R T
authors.initials: RT
authors.lastname: Chang
authors.affiliation: Byers Eye Institute, Stanford University, Palo Alto, CA, USA.
authors.forename: K
authors.initials: K
authors.lastname: Singh
authors.affiliation: Department of Applied Mathematics, Hong Kong Polytechnic University, Hong Kong, People's Republic of China.
authors.forename: C C L
authors.initials: CC
authors.lastname: Liu
authors.affiliation: Department of Ophthalmology, University of Hong Kong, Hong Kong, People's Republic of China.
authors.forename: R
authors.identifier: 0000000163820661
authors.initials: R
authors.lastname: Gangwani
authors.affiliation: Department of Ophthalmology, Queen Mary Hospital, Hong Kong, People's Republic of China.
authors.forename: M O M
authors.initials: MO
authors.lastname: Wong
authors.affiliation: Department of Ophthalmology, University of Hong Kong, Hong Kong, People's Republic of China.
authors.forename: J S M
authors.initials: JS
authors.lastname: Lai
mesh_terms: D002452:Cell Count; D015331:Cohort Studies; D055954:Corneal Endothelial Cell Loss / Q000209:etiology* / Q000503:physiopathology; D063171:Corneal Pachymetry; D004728:Endothelium, Corneal / Q000473:pathology*; D005260:Female; D005902:Glaucoma, Open-Angle / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D053685:Laser Therapy / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D041623:Tomography, Optical Coherence; D014129:Trabecular Meshwork / Q000503:physiopathology / Q000601:surgery*; D014130:Trabeculectomy / Q000009:adverse effects*; D014792:Visual Acuity / Q000502:physiology