Relationship between retinal nerve fiber layer and visual field sensitivity as measured by optical coherence tomography in chiasmal compression.
OBJECTIVE
To investigate the spatial relationship between retinal nerve fiber layer (RNFL) thickness measured with optical coherence tomography (OCT) and visual field sensitivity (VFS) measured by standard automated perimetry (SAP) in chiasmal compression.


METHODS
Twenty-six patients with chiasmal compression were enrolled. RNFL thickness was measured with the StratusOCT and VFS with SAP (Humphrey Field Analyzer; both from Carl Zeiss Meditec, Dublin, CA). Relationships between RNFL thickness (in clock hours, hemifields, and sectors) and VFS (zones were divided into hemifields, quadrants, and sectors based on a validated visual field map) expressed in a decibel scale and 1/lambert (L) were evaluated by linear and nonlinear regression. Coefficients of determination (R(2)) were calculated by using a multivariate model.


RESULTS
Average RNFL thickness correlated strongly with pattern standard deviation (PSD; R = 0.622) and mean deviation (MD; R = 0.413). The four strongest correlations were between the 8 o'clock OCT position (temporal disc), with the temporal hemifield (R = -0.813), the superotemporal quadrant (R = -0.847), the inferotemporal quadrant (R = -0.855), and the field sector representing the papillomacular bundle (R = -0.809). Coefficients of determination improved significantly in all sectors when time since surgery was included in the regression model-most notably, average thickness and 1/L (R(2) = 0.35-0.49), the decibels (R(2) = 0.31-0.47), and the temporal sector (R(2) = 0.44-0.57).


CONCLUSIONS
This is the first study to compare the structure-function correlation of RNFL measured by OCT with SAP in patients with chiasmal compression. RNFL is topographically related globally and sectorally to decreased SAP, with the temporal sectors showing the strongest correlations. The correlation between RNFL and VFS strengthens as the time from surgical intervention increases.
Danesh-Meyer
Helen V
HV
Neuro-ophthalmology Service, Department of Ophthalmology, University of Auckland, Auckland, New Zealand. h.daneshmeyer@auckland.ac.nz
Carroll
Stuart C
SC
Foroozan
Rod
R
Savino
Peter J
PJ
Fan
Jennifer
J
Jiang
Yannan
Y
Vander Hoorn
Stephen
S
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009408:Nerve Compression Syndromes / Q000175:diagnosis*; D009412:Nerve Fibers / Q000473:pathology*; D009897:Optic Chiasm / Q000473:pathology*; D009901:Optic Nerve Diseases / Q000175:diagnosis*; D012165:Retinal Ganglion Cells / Q000473:pathology*; D012680:Sensitivity and Specificity; D041623:Tomography, Optical Coherence / Q000379:methods*; D058609:Visual Field Tests / Q000379:methods; D014794:Visual Fields / Q000502:physiology*