title: Correlation between frequency doubling technology and heidelberg retina tomograph.
abstract: OBJECTIVE
  To evaluate the association between Heidelberg Retina Tomograph (HRT) parameters and the Frequency Doubling Technology (FDT) indices in ocular hypertension or primary open angle glaucoma patients.
  
  
  METHODS
  One eye was randomly chosen from 85 patients with primary open angle glaucoma (abnormal visual field and/or abnormal optic nerve and untreated IOP > 21 mm Hg) and ocular hypertension (normal visual field and normal optic nerve and untreated IOP > 21 mm Hg). All the patients were examined with Humphrey Perimeter program 30-2 full threshold, FDT program C 20-5, and HRT. Findings were analyzed using Pearson's correlation coefficient and linear regression.
  
  
  RESULTS
  Within the entire sample of studied subjects we found a statistically significant correlation (Pearson's r) (P < 0.05) between FDT mean deviation and RA, CA, RV, CSM, RNFLt, and RNFLc of HRT, and between FDT pattern standard deviation and RA, CA, VOLC, CV, RV, CSM, RNFLt, and RNFLc of HRT. Linear regression analysis showed that cup shape measure was the most predictive parameter for FDT MD. No correlation was found between HRT parameters and FDT PSD indices in the glaucoma subgroup; in the ocular hypertensive subgroup some correlation was found between FDT PSD and some of the HRT parameters.
  
  
  CONCLUSIONS
  In the entire group, cup shape measure showed to be the most significant factor correlating functional and morphologic changes. The presence of significant correlations between some HRT parameters and visual field indices in the ocular hypertensive and glaucoma subgroup suggested that HRT parameters and FDT indices could detect glaucoma damage differently.
authors.affiliation: Department of Neurological Sciences, Ophthalmology, Genetic, Clinica Oculistica, University of Genoa, Genoa, Italy. iester@unige.it
authors.forename: Michele
authors.initials: M
authors.lastname: Iester
authors.forename: Carlo E
authors.initials: CE
authors.lastname: Traverso
authors.forename: Fabio
authors.initials: F
authors.lastname: De Feo
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Sanna
authors.forename: Michele
authors.initials: M
authors.lastname: Altieri
authors.forename: Paolo
authors.initials: P
authors.lastname: Vittone
authors.forename: Giovanni
authors.initials: G
authors.lastname: Calabria
mesh_terms: D005902:Glaucoma, Open-Angle / Q000175:diagnosis*; D006801:Humans; D007429:Intraocular Pressure; D007834:Lasers; D009412:Nerve Fibers / Q000473:pathology*; D009798:Ocular Hypertension / Q000175:diagnosis; D009898:Optic Disk / Q000473:pathology*; D009901:Optic Nerve Diseases / Q000175:diagnosis*; D014054:Tomography / Q000379:methods; D014786:Vision Disorders / Q000175:diagnosis*; D058609:Visual Field Tests / Q000379:methods; D014794:Visual Fields