Retinal Nerve Fiber Layer Thickness Changes in the Pseudoexfoliation Syndrome: A Meta-Analysis of Case-Control Studies

Abstract

Purpose: To evaluate and compare changes in retinal nerve fiber layer (RNFL) thickness in patients with the pseudoexfoliation syndrome (PXS) and healthy controls. Methods: Case-control studies were selected through an electronic search of the Cochrane Controlled Trials Register, PubMed, and Embase. Results were reviewed to ensure that the included studies met prespecified inclusion/exclusion criteria, and the quality of each study was assessed using the Newcastle-Ottawa Scale. All included studies measured average and 4-quadrant (temporal, superior, nasal, and inferior) RNFL thickness using optical coherence tomography (OCT). For the continuous outcomes, we calculated the weighted mean difference (WMD) and 95% confidence intervals (CIs). Results: Eight case-control studies were included in this meta-analysis involving 225 eyes of PXS patients and 208 eyes of healthy controls in total. Statistical analysis revealed that the average RNFL thickness in PXS patients was significantly reduced compared to healthy controls (WMD = −6.91, 95% CI: −9.99 to −3.82, p < 0.0001). Additionally, differences in RNFL thickness in the superior quadrant (WMD = −10.68, 95% CI: −16.40 to −4.95, p = 0.0003), inferior quadrant (WMD = −8.20, 95% CI: −10.85 to −5.55, p < 0.00001), nasal quadrant (WMD = −3.05, 95% CI: −5.21 to −0.90, p = 0.005), and temporal quadrant (WMD = −6.39, 95% CI: −9.98 to −2.80, p = 0.0005) were all significant between the two groups. Conclusions: These results suggest that it is important to evaluate RNFL thickness and the optic nerve head through OCT in patients with PXS in order to determine early glaucomatous damage and start timely intervention prior to visual field loss.

Comparison of the retinal nerve fiber layer and ganglion cell complex thickness in Korean patients with unilateral exfoliation syndrome and healthy subjects

“…In the present study, patients with unilateral XFS without glaucomatous optic nerve changes or visual field defects showed thinner RNFL and GCC thicknesses than those of control individuals. Our results were similar to those of previous individual studies and meta-analysis [ 12 , 15 , 18 ]. Our study demonstrated reduced RNFL and GCC thicknesses in superior quadrants.…”

“…Subgroup analysis demonstrated no significant differences in the nasal quadrant regardless of OCT type in their study [ 18 ]. Moreover, publication bias was found in average RNFL thickness and inferior RNFL thickness [ 18 ]. Thus, their results seem similar to our own.…”

“…However, controversies regarding location of thinning still abound. Previous meta-analysis showed that RNFL thickness was significantly lower in all quadrants in XFS patients compared with control group [ 18 ]. In their study, the weighted mean difference was −10.68 in superior, −8.20 in inferior, −6.39 in temporal, and −3.05 in nasal quadrants [ 18 ].…”

“…Previous meta-analysis showed that RNFL thickness was significantly lower in all quadrants in XFS patients compared with control group [ 18 ]. In their study, the weighted mean difference was −10.68 in superior, −8.20 in inferior, −6.39 in temporal, and −3.05 in nasal quadrants [ 18 ]. Subgroup analysis demonstrated no significant differences in the nasal quadrant regardless of OCT type in their study [ 18 ].…”

“…In their study, the weighted mean difference was −10.68 in superior, −8.20 in inferior, −6.39 in temporal, and −3.05 in nasal quadrants [ 18 ]. Subgroup analysis demonstrated no significant differences in the nasal quadrant regardless of OCT type in their study [ 18 ]. Moreover, publication bias was found in average RNFL thickness and inferior RNFL thickness [ 18 ].…”