Systematic review of macular ganglion cell complex analysis using spectral domain optical coherence tomography for glaucoma assessment

Correlation of Macular Ganglion Cell Layer + Inner Plexiform Layer (GCL + IPL) and Circumpapillary Retinal Nerve Fiber Layer (cRNFL) Thickness in Glaucoma Suspects and Glaucomatous Eyes

Purpose

The study aimed to correlate macular ganglion cell layer + inner plexiform layer (GCL + IPL) thickness and circumpapillary retinal nerve fiber layer (cRNFL) thickness and to determine the validity of GCL + IPL in the evaluation of glaucoma across different stages using the area under the curve (AUC) analysis in comparison to cRNFL.

Patients and Methods

The charts of 260 adult glaucoma suspect and glaucoma patients having macular ganglion cell analysis, optical coherence tomography (OCT) of the cRNFL and automated visual field (AVF) were reviewed. GCL + IPL thickness (average, minimum and sectoral) and sectoral cRNFL thickness were obtained. Glaucomatous eyes were further classified into stages based on the Hodapp-Anderson-Parrish Visual Field Criteria of Glaucoma Severity. AUC analysis was used to compare GCL + IPL parameters with cRNFL in glaucoma suspects and glaucoma patients.

Results

A total of 122 eyes were included in the study and were grouped into glaucoma suspects (n = 43), early or mild glaucoma (n = 40), and moderate-to-severe glaucoma (n = 39). Both GCL + IPL and cRNFL thickness parameters showed a significant decline with greater glaucoma severity. In the determination of visual field defects across all glaucoma stages, the highest AUC was obtained by minimum GCL + IPL (AUC = 0.859) with cut-off value at ≤70 µm. Average GCL + IPL had the highest AUC (0.835) in detecting progression from glaucoma suspect to mild glaucoma, while the inferior sector of the cRNFL had the highest AUC (0.937) in discerning mild from moderate-to-severe glaucoma.

Conclusion

The results of this study highlight the significance of macular ganglion cell analysis in the screening, detection and staging of glaucoma. Compared to cRNFL, macular ganglion analysis may be more beneficial in glaucoma screening and detecting progression from glaucoma suspect to mild glaucoma.

Characteristics of the inner retinal layer in the fellow eyes of patients with unilateral exudative age-related macular degeneration

OBJECTIVE

To investigate the thicknesses of the ganglion cell-inner plexiform layer (GC-IPL) and retinal nerve fiber layer (RNFL) of the fellow eyes of patients with unilateral exudative age-related macular degeneration (AMD).

METHODS

A total of 107 patients with unilateral exudative AMD [34 of typical choroidal neovascularization (tCNV), Group A; 73 of polypoidal choroidal vasculopathy (PCV), Group B] and 73 normal control eyes (Group C) were included. Drusen and subretinal drusenoid deposits were assessed in all participants using fundus photography, autofluorescence, and optical coherence tomography (OCT). The GC-IPL and RNFL thicknesses were measured using Cirrus HD-OCT and compared among groups. Linear regression analyses were used to evaluate the factors associated with GC-IPL thicknesses.

RESULTS

The average GC-IPL thicknesses of Groups A, B, and C were 77.09 ± 3.87, 80.10 ± 6.61, and 80.88 ± 6.50 μm, respectively (p = 0.022). Sectoral GC-IPLs and central macular thicknesses (CMTs) were significantly different among groups (all, p <0.05), whereas none of the RNFL parameters differed significantly (all, p >0.05). Multivariate linear regression analyses revealed that age (p <0.001), CMT (p <0.001), and tCNV (p = 0.013) were significantly associated with average GC-IPL thickness, and the rate of reduction of GC-IPL thickness with increasing age in the fellow eyes of tCNV patients was higher than those in the PCV and control groups.

CONCLUSIONS

Unilateral tCNV patients exhibited statistically significant reduction of the GC-IPL thickness in the fellow eyes, compared to values of the fellow eyes of unilateral PCV patients or control patients. RNFL values trended to be lower but did not reach statistical significance.

Ocular changes during hemodialysis in patients with end-stage renal disease

Background

To explore ocular changes during hemodialysis (HD) in chronic renal failure patients and to determine the effects of different causes of renal failure during HD.

Methods

A total of 90 eyes from 45 end-stage renal disease (ESRD) patients undergoing HD were evaluated in this study. All ophthalmological examinations were conducted within 1 h before and after a single HD session. The HD patients were divided into primary kidney disease (KD), hypertensive KD, diabetic KD (DM-KD) and unknown etiology subgroups according to the primary etiology of renal failure. The statistics of 38 eyes from 19 healthy people were set as normal control.

Results

Tear break-up time (TBUT) (P = 0.020), Schirmer’s I test results (P = 0.030), anterior chamber depth (ACD) (P = 0.006), lens thickness (LT) (P < 0.001) and choroidal thickness (CHT) (P < 0.001)decreased significantly after a single HD. The retinal nerve fiber layer (RNFL) thickness and average retinal thickness (RT) increased after HD, especially in the nasal inner macula (NIM) subfield (P < 0.001), the inferior inner macula (IIM) subfield (P = 0.004) and the superior outer macula (SOM) subfield (P = 0.012). TBUT, Schirmer’s I test, IOP, RT, and CHT were correlated with one or more parameters. All ESRD patients regardless of etiology had the same trend for most parameters during HD, with the exception of the logMAR of BCVA, central corneal thickness, RNFL thickness and CHT.

Conclusions

HD may affect a range of ocular parameters in ESRD patients. Dry eye parameters, RT and CHT exhibited the most obvious changes. Different etiologies tended to have similar trends in ocular parameter changes during HD.

[Progression of nerve fiber layer defects in retrobulbar optic neuritis by the macular ganglion cell complex]

INTRODUCTION

Recent studies with SD OCT had shown early axonal damage to the macular ganglion cell complex (which consists of the three innermost layers of the retina: Inner Plexiform Layer [IPL], Ganglion Cell Layer [GCL], Retinal Nerve Fibre layer [RNFL]) in optic nerve pathology. Retrobulbar optic neuritis (RBON), occurring frequently in demyelinating diseases, leads to atrophy of the optic nerve fibers at the level of the ganglion cell axons, previously described in the literature. The goal of this study is to evaluate the progression of optic nerve fiber defects and macular ganglion cell complex defects with the SPECTRALIS OCT via a reproducible method by calculating a mean thickness in each quadrant after an episode of retrobulbar optic neuritis.

METHODS

This is a prospective monocentric observational study including 8 patients at the Clermont-Ferrand university medical center. All patients underwent ocular examination with macular and disc OCT analysis and a Goldmann visual field at the time of inclusion (onset or recurrence of RBON), at 3 months and at 6 months.

RESULTS

Patients were 40-years-old on average at the time of inclusion. After 6 months of follow-up, there was progression of the atrophy of the macular ganglion cell complex in the affected eye on (11.5% or 11μm) predominantly inferonasally (13.9% or 16μm) and superonasally (12.9% or 14μm) while the other eye remained stable. The decrease in thickness occurred mainly in the most internal 3 layers of the retina. On average, the loss in thickness of the peripapillary RNFL was predominantly inferotemporal (24.9% or 39μm) and superotemporal (21.8% or 28μm).

DISCUSSION

In 3 months of progression, the loss of optic nerve fibers is already seen on macular and disc OCT after an episode of RBON, especially in inferior quadrants in spite of the improvement in the Goldmann visual field and visual acuity. Segmentation by quadrant was used here to compare the progression of the defect by region compared to the fovea in a global and reproducible way. The loss of thickness, predominantly inferonasally and superonasally, appears to correspond to the temporal loss on optic nerve OCT according to the literature.

CONCLUSION

The follow-up of these patients with retrobulbar neuritis is important as shown by the possibility of relapse, especially in multiple sclerosis. Monitoring of the macular ganglion cell complex by a global method of calculation could contribute to the detection and localization of early damage after an episode of retrobulbar neuritis. This could possibly lead to a discussion of treatment modification or increased surveillance in cases of early detection of nerve fiber atrophy, or to showing the importance of monitoring, since monitoring of RBON is not standardized.