Abstract
Purpose: :
To evaluate the strength of relationship between visual field (VF) sensitivity and retinal nerve fiber layer (RNFL) thickness as measured by scanning laser polarimetry (SLP) with enhanced corneal compensation (ECC) and variable corneal compensation (VCC) in the eyes with open angle glaucoma.
Methods: :
Thirty–six glaucomatous eyes with typical retardation pattern (TRP) and 27 glaucomatous eyes with atypical retardation pattern (ARP; typical scan score < 80) were imaged with SLP–ECC and SLP–VCC. VF examination was performed with Humphrey Field Analyzer (HFA). Relationships between VF sensitivity and RNFL thickness as measured by SLP–ECC and SLP–VCC were sought globally and regionally in each group. For global analysis, TSNIT average and NFI were matched with mean deviation (MD) and pattern standard deviation (PSD) in each group. For regional analysis, retinal sensitivities and VF severity scores of each hemifield were matched with regional SLP parameters and deviation map severity scores of opposite quadrants.
Results: :
For all subjects, TSNIT average and NFI correlated well with global VF indices in both SLP–ECC and SLP–VCC images (p<0.05). Regional SLP parameters and deviation map severity scores also correlated positively with mean retinal sensitivities of the opposite hemifield and VF severity scores as measured by HFA (p<0.05). When grouped by retardation pattern of scan images, however, the strength of relationship between VF sensitivity and RNFL thickness was greater with SLP–ECC than with SLP–VCC globally (R2; 0.30–0.40 for VCC and 0.56–0.65 for ECC) and regionally (R2; 0.36–0.42 for VCC and 0.54–0.70 for ECC) in ARP group. The strength of relationship between VF sensitivity and RNFL thickness in TRP group was similar between SLP–VCC and SLP–ECC.
Conclusions: :
The strength of the structure–function relationship was better with SLP–ECC than SLP–VCC in glaucomatous eyes with ARP scan images.
Keywords: imaging/image analysis: clinical • nerve fiber layer • visual fields