Association between localized visual field losses and thickness deviation of the nerve fiber layer in glaucoma.
OBJECTIVE
To perform a correlation between morphology and function by studying local perimetric field losses and thickness reduction of the nerve layer in corresponding areas.


METHODS
Forty-seven patients with "preperimetric" open-angle glaucoma, 95 patients with "perimetric" open-angle glaucoma, and 75 control subjects had perimetric (Octopus) and polarimetric measurements. Criteria for exclusion: optic discs larger than 4 mm, media opacities, polarimetric hourglass pattern in the macular image. Thickness values of the retinal nerve fiber layer were determined in 14 upper and 14 lower sectors (10 degrees each) as well as nasally and temporally (40 degrees each) as provided from the GDx (software version 4000). The healthy control subjects served to determine age-corrected thickness deviation in all sectors. Analyses were calculated in eight nerve fiber bundle related areas. Due to non-linear relationships between perimetric defects and corresponding thickness deviation non-parametric tests were used.


RESULTS
Localized visual field defects in the present perimetric patients were highest in upper and lower visual field areas abutting the nasal meridian. Thickness loss of nerve fiber layer however was highest in more circumferential upper and lower nerve fiber bundles. Correlations between local mean defects and deviation of the retinal nerve fiber layer thickness from normals showed a clear association for corresponding areas. The correlation coefficients were significant (P < 0.01) for all arcuate superior and inferior visual field zones except horizontally and not for the area of the lower nasal step.


CONCLUSIONS
The present correspondence map indicates that focal perimetric defects can be identified best polarimetrically if they occur in the arcuate bundles of the visual field. A lack of correspondence was observed in the area of the papillo-macular bundle.
Horn
Folkert K
FK
Department of Ophthalmology and University Eye Hospital, Friedrich-Alexander University Erlangen-Nürnberg at Erlangen, Germany. folkert.horn@augen.imed.uni-erlangen.de
Mardin
Christian Y
CY
Viestenz
Arne
A
Jünemann
Anselm G
AG
D005260:Female; D005902:Glaucoma, Open-Angle / Q000175:diagnosis*; D006801:Humans; D007429:Intraocular Pressure; D007834:Lasers; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology*; D009887:Ophthalmoscopy / Q000379:methods; D009898:Optic Disk / Q000473:pathology; D009901:Optic Nerve Diseases / Q000175:diagnosis*; D012165:Retinal Ganglion Cells / Q000473:pathology*; D012607:Scotoma / Q000175:diagnosis*; D014065:Tonometry, Ocular; D058609:Visual Field Tests / Q000379:methods; D014794:Visual Fields