title: Correlation between central corneal thickness and visual field defects, cup to disc ratio and retinal nerve fiber layer thickness in primary open angle glaucoma patients.
abstract: OBJECTIVE
  To evaluate the correlation between Central Corneal Thickness (CCT) and Visual Field (VF) defect parameters like Mean Deviation (MD) and Pattern Standard Deviation (PSD), Cup-to-Disc Ratio (CDR) and Retinal Nerve Fibre Layer Thickness (RNFL-T) in Primary Open-Angle Glaucoma (POAG) patients.
  
  
  METHODS
  This cross sectional study was conducted at Armed Forces Institute of Ophthalmology (AFIO), Rawalpindi from September 2015 to September 2016. Sixty eyes of 30 patients with diagnosed POAG were analysed. Correlation of CCT with other variables was studied.
  
  
  RESULTS
  Mean age of study population was 43.13±7.54 years. Out of 30 patients, 19 (63.33%) were males and 11 (36.67%) were females. Mean CCT, MD, PSD, CDR and RNFL-T of study population was 528.57±25.47µm, -9.11±3.07, 6.93±2.73, 0.63±0.13 and 77.79±10.44µm respectively. There was significant correlation of CCT with MD, PSD and CDR (r=-0.52, p<0.001; r=-0.59, p<0.001;r=-0.41, p=0.001 respectively). The correlation of CCT with RNFL-T was not statistically significant (r=-0.14, p=0.284).
  
  
  CONCLUSIONS
  Central corneal thickness had significant correlation with visual field parameters like mean deviation and pattern standard deviation, as well as with cup-to-disc ratio. However, central corneal thickness had no significant relationship with retinal nerve fibre layer thickness.
authors.affiliation: Dr. Muhammad Haroon Sarfraz, MBBS. Armed Forces Institute of Ophthalmology, Rawalpindi, Pakistan.
authors.forename: Muhammad Haroon
authors.initials: MH
authors.lastname: Sarfraz
authors.affiliation: Dr. Mohammad Asim Mehboob, MBBS. PNS Shifa Naval Hospital Karachi, Pakistan.
authors.forename: Mohammad Asim
authors.initials: MA
authors.lastname: Mehboob
authors.affiliation: Dr. Rana Intisar ul Haq, MCPS(Ophth), FCPS(Ophth). Armed Forces Institute of Ophthalmology, Rawalpindi, Pakistan.
authors.forename: Rana Intisar Ul
authors.initials: RI
authors.lastname: Haq
keywords: Central Corneal Thickness; Cup to Disc Ratio; Layer Thickness; Primary open-angle glaucoma; Retinal Nerve Fibre; Visual field