title: Assessment of anterior segment parameters under photopic and scotopic conditions in Indian eyes using anterior segment optical coherence tomography.
abstract: OBJECTIVE
  To compare the anterior segment parameters in photopic and scotopic conditions using anterior segment optical coherence tomography (AS OCT) in Indian eyes.
  
  
  METHODS
  One hundred eyes of 100 normal subjects of both sexes, aged 19 to 76 years, underwent anterior segment evaluation by AS OCT (Visante OCT). Central corneal thickness (CCT), central anterior chamber depth (ACD), pupil diameter (PD) and the temporal and nasal peripheral irido-corneal angles were assessed in photopic and scotopic conditions. These anterior segment parameters were stratified for age, sex and refractive error.
  
  
  RESULTS
  Mean values of the parameters measured in photopic and scotopic conditions respectively were as follows: ACD (mm) 2.88 +/- 0.32, 2.89 +/- 0.32 (P = 0.10); nasal angle (degrees) 28.80 +/- 5.91, 22.28 +/- 7.50 (P < 0.001); temporal angle (degrees) 29.95 +/- 6.74, 22.82 +/- 8.43 (P < 0.001); pupil diameter (mm) 4.08 +/- 0.91, 4.68 +/- 0.92 (P < 0.001); CCT (microm) 519 +/- 33.88, 519 +/- 33.88.
  
  
  CONCLUSIONS
  There was no significant difference in the ACD in photopic and scotopic conditions. While the nasal and temporal angles showed a significant decrease, the pupil diameter showed a significant increase in scotopic conditions. Mean central ACD decreased with age and was shallower in females than in males. It was highest in myopes and lowest in hypermetropes. CCT was not influenced by photopic and scotopic conditions.
authors.affiliation: The Eye Research Foundation, Vijaya Hospital, Chennai, India. shaundacosta@yahoo.com
authors.forename: Shaun
authors.initials: S
authors.lastname: Dacosta
authors.forename: Gitanjali
authors.initials: G
authors.lastname: Fernandes
authors.forename: Babu
authors.initials: B
authors.lastname: Rajendran
authors.forename: P
authors.initials: P
authors.lastname: Janakiraman
mesh_terms: D000328:Adult; D000368:Aged; D000869:Anterior Eye Segment / Q000033:anatomy & histology*; D005260:Female; D006801:Humans; D008029:Lighting; D008297:Male; D008875:Middle Aged; D012029:Refraction, Ocular; D041623:Tomography, Optical Coherence