title: Variation of angle parameters in asians: an anterior segment optical coherence tomography study in a population of singapore malays.
abstract: OBJECTIVE
  To assess variations in angle parameters using anterior segment optical coherence tomography (AS-OCT) and to investigate demographic, ocular and systemic associations of angle width.
  
  
  METHODS
  This was a substudy of a population based, cross-sectional survey of 3280 (78.7% response rate) Malay people aged 40 to 80 years in Singapore. All participants underwent a standardized interview and ocular and systemic examination. AS-OCT was performed on 291 consecutive patients in standardized dark conditions. Angle opening distance (AOD-500) and trabecular-iris space area (TISA-500) 500 microm from the scleral spur were determined for the nasal and temporal angles. Anterior chamber depth (ACD) was also measured.
  
  
  RESULTS
  AS-OCT measurements were analyzed in 239 (82.1%) right eyes. Mean AOD 500 was smaller in women than in men, both nasally (0.255 vs. 0.293 mm, P = 0.026) and temporally (0.245 vs. 0.286 mm, P = 0.023). Mean TISA-500 was smaller in women in the nasal quadrant only (0.104 vs. 0.117 mm, P = 0.035). Mean ACD was smaller in women than in men (2.71 vs. 2.87 mm, P = 0.001). Multiple linear regression showed that axial length and ACD were significantly associated with AOD-500 and TISA-500 both nasally (adjusted R(2) = 0.34 for AOD-500 and 0.20 for TISA-500) and temporally (adjusted R(2) = 0.35 for AOD-500 and 0.24 for TISA-500). Body mass index, HbA(1c), systolic blood pressure, intraocular pressure, cup-to-disc ratio, and central corneal thickness were not significantly associated with AOD-500, TISA-500, or ACD.
  
  
  CONCLUSIONS
  In this Malay population, angle width measured by AS-OCT was smaller in women than in men, and in eyes with shorter axial length and shallower ACD.
authors.affiliation: Singapore National Eye Centre, Singapore.
authors.forename: Nishani
authors.initials: N
authors.lastname: Amerasinghe
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Foster
authors.forename: Tien Yin
authors.initials: TY
authors.lastname: Wong
authors.forename: Hla Myint
authors.initials: HM
authors.lastname: Htoon
authors.forename: Mingguang
authors.initials: M
authors.lastname: He
authors.forename: Sunny Y
authors.initials: SY
authors.lastname: Shen
authors.forename: Han T
authors.initials: HT
authors.lastname: Aung
authors.forename: Seang-Mei
authors.initials: SM
authors.lastname: Saw
authors.forename: Tin
authors.initials: T
authors.lastname: Aung
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000867:Anterior Chamber / Q000033:anatomy & histology; D000869:Anterior Eye Segment / Q000033:anatomy & histology*; D044466:Asian People / Q000208:ethnology*; D001794:Blood Pressure; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006068:Gonioscopy; D006801:Humans; D007429:Intraocular Pressure; D007498:Iris / Q000033:anatomy & histology; D008297:Male; D008875:Middle Aged; D012846:Singapore / Q000453:epidemiology; D041623:Tomography, Optical Coherence; D014129:Trabecular Meshwork / Q000033:anatomy & histology
chemical_list: D006442:Glycated Hemoglobin