Fig 1.
A) Peripapillary retinal thickness profile obtained automatically by changing the layer box from retinal nerve fiber layer into retina. B) The automatically calculated areas of a pixel unit in the peripapillary quadrant using the image J program (1 = total, 2 = temporal blue area, 3 = superior yellow area, 4 = nasal red area, and 5 = inferior green area). C) Overlapping portion of the temporal retinal nerve fiber layer (RNFL) thickness and the 6th subfield area (yellow area) in the Early Treatment Diabetic Retinopathy Study (ETDRS). The blue area represents the central subfield thickness (CST).
Fig 2.
Scatter plots of generalized equations between overall peripapillary retinal thickness and retinal nerve fiber layer thickness.
Table 1.
Comparison of baseline characteristics between eyes with non-proliferative diabetic retinopathy with or without diabetic macular edema.
Table 2.
Comparison of changes in retinal nerve fiber layer thickness during 6-month follow up period in eyes with non-proliferative diabetic retinopathy with or without diabetic macular edema.
Table 3.
Comparison of changes in central subfield thickness and peripapillary retinal thickness during 6-month follow up period in eyes with non-proliferative diabetic retinopathy with or without diabetic macular edema.
Fig 3.
The similar profiles of RNFL thickness and retinal thickness change in the peripapillary area.
A) The red arrows indicate the increase of peripapillary RNFL thickness during the 6-month follow up period (gray line at baseline and thick black line at 6 months). B) The blue arrows indicate the increase of peripapillary retinal thickness during the follow up period (gray line at baseline and thick black line at 6 months).
Fig 4.
Scatter plots of generalized equations between the 6th EDTRS subfield retinal thickness and peripapillary retinal nerve fiber layer thickness.
A) and B) show the relationship between the 6th subfield retinal thickness and average or temporal RNFL thickness in patients with diabetic macular edema (group I). C) and D) show the relationship between the 6th subfield retinal thickness and average or temporal RNFL thickness in patients without diabetic macular edema (group II).
Table 4.
Correlation coefficient between the peripapillary RNFL thickness and topographic findings at baseline and 6 months in eyes with non-proliferative diabetic retinopathy with or without diabetic macular edema.
Table 5.
Comparison of average changes of adjusted retinal nerve fiber layer thickness Index during 6-month follow up period in eyes with non-proliferative diabetic retinopathy with or without diabetic macular edema.
Fig 5.
Average peripapillary retinal nerve fiber layer (RNFL) thickness, corresponding peripapillary retinal thickness, and RNFL index change during the 6-month follow up period in the 2 groups.
A) Eyes with diabetic macular edema (DME) show RNFL thinning (diamond marks) after anti-VEGF injection, but RNFL index after peripapillary retinal edema correction shows no change (rectangular marks). B) Eyes with no DME show no significant change in RNFL thickness (diamond marks) relative to the retinal thickness and RNFL index (rectangular marks) shows no change, similar to that in the DME group. *P < 0.01 (P values less than 0.01 were considered statistically significant).
Fig 6.
Spectral-Domain optical coherence tomography images (upper) before and (lower) 6 months after anti-VEGF injection for comparing changes between central subfield thickness (CST), temporal peripapillary retinal nerve fiber layer (RNFL) thickness in two patients with diabetic macular edema.
A) Case 1: The RNFL thicknesses in all quadrants decreased following the CST decrease. B) Case 2: Even though the central subfield thickness reduced (437 μm → 297 μm) after anti-VEGF injection, the temporal RNFL thickness increased (68 μm → 74 μm), as did the 6th subfield thickness (335 μm → 340 um).