title: A prospective comparison of chronic primary angle-closure glaucoma versus primary open-angle glaucoma in Singapore.
abstract: BACKGROUND
  To describe the optic disc, visual field and ocular characteristics of a consecutive cohort of Asian patients with chronic primary angle-closure glaucoma (CPACG), and compare them with those having primary open-angle glaucoma (POAG).
  
  
  METHODS
  In a prospective comparative case series of new patients with POAG or CPACG in Singapore, all patients underwent visual acuity assessment, slit-lamp examination, tonometry, gonioscopy, refraction, Heidelberg Retina Tomograph (HRT) and Humphrey visual field (HVF) assessment.
  
  
  RESULTS
  98 patients were enrolled (POAG n = 48; CPACG n = 50). CPACG patients were significantly older (66.5 ± 9.2 years vs. 64.1 ± 13.5 years; p = 0.027) and mostly female (p = 0.004). CPACG eyes had significantly higher intraocular pressure (26.9 ± 6.9 mmHg vs. 24.5 ± 3.3 mmHg; p = 0.03), shorter axial length (22.89 ± 0.97 mm vs. 24.26 ± 1.79 mm; p < 0.001) and shallower anterior chamber depth (2.60 ± 0.25 mm vs. 3.16 ± 0.48 mm; p < 0.001). HVF mean deviation or pattern standard deviation (PSD) did not differ significantly between POAG and CPACG eyes, but the latter had a lower PSD for a given mean deviation. HRT parameters between the two groups were not significantly different.
  
  
  CONCLUSIONS
  In this study, CPACG eyes had significantly higher presenting intraocular pressure than POAG eyes, but there were no significant differences in optic disc topography. A majority of the patients in both groups had moderate field defects at the time of presentation, followed by severe and then mild defects. The field loss in CPACG eyes was more diffuse than that in POAG eyes.
authors.affiliation: Department of Ophthalmology, National University Hospital, 1E Kent Ridge Road, Singapore. cherylngo@gmail.com
authors.forename: Cheryl S F
authors.initials: CS
authors.lastname: Ngo
authors.forename: Maria Cecilia
authors.initials: MC
authors.lastname: Aquino
authors.forename: Shabana
authors.initials: S
authors.lastname: Noor
authors.forename: Seng Chee
authors.initials: SC
authors.lastname: Loon
authors.forename: Chelvin C A
authors.initials: CC
authors.lastname: Sng
authors.forename: Gus
authors.initials: G
authors.lastname: Gazzard
authors.forename: Wan-ling
authors.initials: WL
authors.lastname: Wong
authors.forename: Paul T K
authors.initials: PT
authors.lastname: Chew
mesh_terms: D000368:Aged; D005260:Female; D015812:Glaucoma, Angle-Closure / Q000175:diagnosis* / Q000473:pathology; D005902:Glaucoma, Open-Angle / Q000175:diagnosis* / Q000473:pathology; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D008875:Middle Aged; D009898:Optic Disk / Q000473:pathology; D011446:Prospective Studies; D012160:Retina / Q000473:pathology; D012846:Singapore; D014054:Tomography; D058609:Visual Field Tests; D014794:Visual Fields