Macular Ganglion Cell–Inner Plexiform Layer Loss Precedes Peripapillary Retinal Nerve Fiber Layer Loss in Glaucoma with Lower Intraocular Pressure

Longitudinal corneal hysteresis changes predict structural progression in medically controlled, early-to-moderate, open-angle glaucoma with a history of refractive surgery

BACKGROUND

The present study aims to identify the relationship between longitudinal changes in corneal hysteresis (CH) and progressive retinal nerve fibre layer (RNFL) thinning in a cohort of medically controlled, early-to-moderate open-angle glaucoma (OAG) patients with a history of laser refractive surgery (LRS).

METHODS

A total of 123 consecutive eyes with a diagnosis of medically controlled (peak intraocular pressure (IOP)<18 mm Hg), early-to-moderate OAG with a history of LRS underwent measurements of CH, corneal-compensated intraocular pressure (IOPcc) and RNFL thicknesses every 6 months. Linear models were used to investigate the relationship between CH change and RNFL thickness change over time.

RESULTS

Of 123 eyes, 30 eyes (24.4%, 42.9±9.3 years, 36.7% males) demonstrated RNFL loss (93 eyes no progression, 44.4±9.6 years, 30.1% males). No statistically significant difference was found in IOP, but significantly greater decrease in CH was noted in the progression group (-2.525% baseline (95% CI -4.974 to -0.076) vs 1.068% baseline (95% CI, -0.322 to 2.458); p=0.013). Relative CH change was greater for more advanced stage of OAG among the progression group. Patients with the greatest relative CH decrease over time was 1.7 times more likely to present RNFL loss (HR 1.705, 95% CI 1.113 to 2.611, p=0.014).

CONCLUSIONS

Longitudinal decrease in CH over time was greater in those showing structural progression than those without progression among medically controlled, early-to-moderate OAG with a history of LRS. Decrease in CH was significantly associated with faster RNFL loss. Larger CH changes indicate a higher risk of OAG progression in those with a history of LRS.

Retinal layer thinning as a predictor of demyelinating diseases of the central nervous system: Insights from a decade-long cohort study

BACKGROUND

Early diagnosis and differentiation of demyelinating diseases of the central nervous system (CNS) are essential for timely treatment but challenged with the limited availability of non-invasive, real-time methods to assess the architecture of the CNS. This study compared the retinal layers between patients with CNS demyelinating diseases and the general population and evaluated the predictive value of these structures in prospective diagnosis.

METHODS

This UK Biobank study, incorporating optical coherence tomography images, analyzed patients with CNS demyelinating diseases identified at recruitment and during follow-up. Cross-sectionally, baseline retinal structures were compared, with diagnostic models constructed following cross-validation. Cox regression was used to assess the risk of future diagnosis in the prospective cohort.

RESULTS

34,230 individuals were included, comprising 61 diagnosed patients. The thickness of the macular ganglion cell-inner plexiform layer (mGCIPL; p = 4.91 × 10-10), papillary retinal nerve fiber layer (pRNFL; p = 9.92 × 10-6), and non-central macular subfields (p value ranging from 1.16 × 10-2 to 1.18 × 10-10) were significantly thinner in the patient group. A diagnostic model incorporating mGCIPL, pRNFL and outer temporal macular thickness achieved the area under the curve of 0.779. During follow-up, 96 patients were newly diagnosed. Multivariable Cox regression revealed thinner mGCIPL (HR: 0.960, 95 % CI: 0.936 to 0.984, p = 0.001) and thinner outer nasal macula (HR: 0.990 95 % CI: 0.983 to 0.997, p = 0.006) as high risk predictors of future diagnosis.

CONCLUSIONS

Retinal structure can serve as non-invasive biomarker for CNS demyelinating diseases and has prospective diagnostic value in identifying pre-clinical and sub-clinical patients.

A Multitrait Open-Angle Glaucoma Polygenic Risk Score Stratifies Risk of Glaucoma Diagnosis and Severity in Eyes with Pseudoexfoliation

PURPOSE

Pseudoexfoliation syndrome (PEX) is a known risk factor for glaucoma, but its individual clinical course ranges from no glaucoma to total blindness. This study investigated whether polygenic risk scores (PRSs) built from variants collectively associated with open-angle glaucoma, intraocular pressure (IOP), and vertical cup-to-disc ratio (VCDR) can stratify individuals with pseudoexfoliation for the risk of glaucoma development.

DESIGN

Retrospective multicohort study of 2 glaucoma registries and 1 population-based cohort.

PARTICIPANTS

For the primary analysis, participants (n = 828) were classified as having PEX with glaucoma, PEX with suspected glaucoma, or PEX with no glaucoma. For the secondary analysis, a cohort of participants (n = 2460) were classified as having PEX with glaucoma, having PEX with no glaucoma, and being unaffected, and an independent cohort of participants (n = 3372) were classified as having primary open-angle glaucoma (POAG) or suspected POAG.

METHODS

Previously published and validated PRSs for open-angle glaucoma, IOP, and VCDR were expressed as a percentile, decile, or tertile of an ancestrally matched healthy population. Multivariable logistic and linear regressions and survival analyses were performed.

MAIN OUTCOME MEASURES

The main outcome measures were odds of pseudoexfoliative glaucoma (PEX-G) and odds of clinically relevant outcomes.

RESULTS

Participants in the top tertile of the glaucoma PRS showed greater odds of receiving a PEX-G diagnosis (adjusted odds ratio [aOR], 4.22; 95% confidence interval [CI], 2.62-6.88; P < 0.001), greater odds of bilateral central vision loss (aOR, 3.43; 95% CI, 1.49-8.99; P = 0.007), and greater odds of bilateral incisional surgery (aOR, 3.35; 95% CI, 1.33-10.24; P = 0.018). Age at PEX-G diagnosis was 1 year younger with each increasing glaucoma PRS decile (1.06 years; 95% CI, 0.59-1.53 years; P < 0.001). Participants with manifest glaucoma and pseudoexfoliation showed a comparatively lower glaucoma PRS than counterparts with POAG.

CONCLUSIONS

The PRSs for open-angle glaucoma, IOP, and VCDR stratify risk of glaucoma development and disease severity among individuals with PEX.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Baseline choroidal microvasculature dropout as a predictor of rapid global structural loss in open-angle glaucoma

This study included 102 open-angle glaucoma (OAG) eyes with or without a localized choroidal microvasculature dropout (CMvD) at the inferior hemiretina, matched for age (≤ 10 years), axial length (≤ 1 mm), and visual field severity (≤ 1dB), and with a minimum 2-year follow-up. Serial thickness [circumpapillary retinal nerve fiber layer (cpRNFLT) and macular ganglion cell-inner plexiform layer thickness (mGCIPLT)], and vessel density (VD) [circumpapillary (cpVD) and macular VD (mVD)] parameters were obtained. The rate of change in each parameter at both the superior (CMvD-unaffected) and inferior (CMvD-affected) hemiretina were compared between matched eyes with (CMvD+) and without CMvD (CMvD-). Clinical factors associated with the rate of change in each parameter both globally and at the CMvD-unaffected hemiretina were also evaluated. CMvD + eyes showed significantly faster rates of VD and thickness loss at both the CMvD-affected and -unaffected hemiretina. In addition, CMvD was significantly associated with rapid loss of both VD and thickness parameters globally and at the CMvD-unaffected superior hemiretina. In conclusion, OAG eyes with CMvD show significantly faster rates of VD and thickness loss at both the CMvD-affected and unaffected hemiretina. A localized CMvD is an independent predictor of globally rapid structural loss in OAG eyes.

OCT-Based Retina Assessment Reflects Visual Impairment in Multiple Sclerosis

Purpose

To explore the relationship between visual performance and retinal morphology as assessed by optical coherence tomography (OCT), and the ability of OCT to reflect visual impairment in people with multiple sclerosis (PwMS) compared with healthy controls (HC).

Methods

We gathered data from two neurology referral centers on PwMS and HC. Neurological and ophthalmological assessments, including OCT, high-contrast visual acuity (HCVA) and low-contrast visual acuity (LCVA), area under the log contrast sensitivity function (AULCSF), and vision-related quality of life (National Eye Institute Visual Function Questionnaire), were conducted between 2018 and 2020, with follow-up at 1 year.

Results

A total of 137 PwMS (271 eyes) and 118 HC (236 eyes) were available for analysis. The peripapillary retinal nerve fiber layer (pRNFL) and the macular ganglion cell layer and inner plexiform layer volume (mGCIPL) volume were both reduced in PwMS (92 µm in PwMS vs 98 µm in HC [P < 0.001], 0.55 mm3 vs 0.62 mm3 [P < 0.001], respectively). A cutoff effect for visual impairment was observed in PwMS when pRNFL fell below 68.8 µm (HCVA), 71.4 µm (LCVA), and 72.6 µm (AULCSF). Using mixed effects models, the mGCIPL volume emerged as the variable most strongly associated with the AULCSF (P < 0.001). The AULCSF showed the strongest correlation with both pRNFL and mGCIPL (P < 0.001), with optic neuritis being a significant contributing factor (P < 0.001).

Conclusions

AULCSF outperformed standard HCVA and LCVA, closely reflecting retinal atrophy. mGCIPL loss showed stronger associations with vision tests and detected neurodegeneration without the cutoff effect seen in pRNFL, making it the best marker for neuronal atrophy.

Peripapillary Versus Macular Thinning to Detect Progression According to Initial Visual Field Loss Location in Normal-Tension Glaucoma

PURPOSE

To investigate the predictive capabilities of peripapillary retinal nerve fiber layer (pRNFL) and macular ganglion cell-inner plexiform layer (mGCIPL) thinning to detect visual field (VF) progression in normal-tension glaucoma patients with an initial parafoveal scotoma (IPFS) or nasal step (INS).

DESIGN

Retrospective cohort study.

METHODS

A total of 185 early-stage glaucoma eyes, followed for 10 years, were retrospectively stratified into IPFS and INS groups. Progressive pRNFL and mGCIPL thinning were assessed using spectral-domain optical coherence tomography and VF progression using both event- or trend-based analysis. Kaplan-Meier survival analysis compared VF survival in each VF phenotype with or without progressive pRNFL and mGCIPL thinning. Cox proportional regression analysis identified VF progression factors.

RESULTS

VF progression was detected in 42 IPFS (n = 86) and 47 INS (n = 99) eyes. Among VF progressors, pRNFL thinning was significantly faster in INS group compared to IPFS group (P < .01), while mGCIPL thinning was similar (P = .16). At 5 years, eyes with progressive mGCIPL thinning showed significantly lower VF survival in both VF phenotypes (all P < .05). Progressive pRNFL thinning showed significantly lower VF survival only in INS eyes (P = .015). Cox multivariate regression revealed that mGCIPL thinning predicted subsequent VF progression in IPFS eyes, while mGCIPL and pRNFL thinning had significant associations with VF progression in INS eyes.

CONCLUSIONS

mGCIPL outperforms pRNFL at early follow-up in detecting VF progression in IPFS eyes but not INS eyes. Appropriate selection of structural parameters (mGCIPL vs. pRNFL) maximizes early VF progression detection according to initial VF defect location.

Macular OCT's Proficiency in Identifying Retrochiasmal Visual Pathway Lesions in Multiple Sclerosis-A Pilot Study

Optical coherence tomography (OCT) is a non-invasive imaging technique based on the principle of low-coherence interferometry that captures detailed images of ocular structures. Multiple sclerosis (MS) is a neurodegenerative disease that can lead to damage of the optic nerve and retina, which can be depicted by OCT. The purpose of this pilot study is to determine whether macular OCT can be used as a biomarker in the detection of retrochiasmal lesions of the visual pathway in MS patients. We conducted a prospective study in which we included 52 MS patients and 27 healthy controls. All participants underwent brain MRI, visual field testing, and OCT evaluation of the thicknesses of the peripapillary retinal nerve fiber layer (pRNFL), macular ganglion cell layer (GCL), and macular inner plexiform layer (IPL). OCT measurements were adjusted for optic neuritis (ON). VF demonstrated poor capability to depict a retrochiasmal lesion identified by brain MRI (PPV 0.50). In conclusion, the OCT analysis of the macula appears to excel in identifying retrochiasmal MS lesions compared to VF changes. The alterations in the GCL and IPL demonstrate the most accurate detection of retrochiasmal visual pathway changes in MS patients.

Sensitivity, Specificity, and Cutoff Identifying Optic Atrophy by Macular Ganglion Cell Layer Volume in Syndromic Craniosynostosis

PURPOSE

To determine the sensitivity, specificity, and cutoff of macular ganglion cell layer (GCL) volume consistent with optic atrophy in children with syndromic craniosynostosis and to investigate factors independently associated with reduction in GCL volume.

DESIGN

Retrospective cross-sectional study.

PARTICIPANTS

Patients with syndromic craniosynostosis evaluated at Boston Children's Hospital (2010-2022) with reliable macular OCT scans.

METHODS

The latest ophthalmic examination that included OCT macula scans was identified. Age at examination, sex, ethnicity, best-corrected logarithm of the minimum angle of resolution (logMAR) visual acuity, cycloplegic refraction, and funduscopic optic nerve appearance were recorded in addition to history of primary or recurrent elevation in intracranial pressure (ICP), Chiari malformation, and obstructive sleep apnea (OSA). Spectral-domain OCT software quantified segmentation of macula retinal layers and was checked manually.

MAIN OUTCOME MEASURES

The primary outcome was determining sensitivity, specificity, and optimal cutoff of GCL volume consistent with optic atrophy. The secondary outcome was determining whether previously elevated ICP, OSA, Chiari malformation, craniosynostosis diagnosis, logMAR visual acuity, age, or sex were independently associated with lower GCL volume.

RESULTS

Median age at examination was 11.9 years (interquartile range, 8.5-14.8 years). Fifty-eight of 61 patients (112 eyes) had reliable macula scans, 74% were female, and syndromes represented were Apert (n = 14), Crouzon (n = 17), Muenke (n = 6), Pfeiffer (n = 6), and Saethre-Chotzen (n = 15). Optimal cutoff identifying optic atrophy was a GCL volume < 1.02 mm3 with a sensitivity of 83% and specificity of 77%. Univariate analysis demonstrated that significantly lower macular GCL volume was associated with optic atrophy on fundus examination (P < 0.001), Apert syndrome (P < 0.001), history of elevated ICP (P = 0.015), Chiari malformation (P = 0.001), OSA (P < 0.001), male sex (P = 0.027), and worse logMAR visual acuity (P < 0.001). Multivariable median regression analysis confirmed that only OSA (P = 0.005), optic atrophy on fundus examination (P = 0.003), and worse logMAR visual acuity (P = 0.042) were independently associated with lower GCL volume.

CONCLUSIONS

Surveillance for optic atrophy by GCL volume may be useful in a population where cognitive skills can limit acquisition of other key ophthalmic measures. It is noteworthy that OSA is also associated with lower GLC volume in this population.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Clinical characteristics of open-angle glaucoma progression with peripapillary microvasculature dropout in different locations

OBJECTIVE

The study attempted to identify clinical characteristics associated with structural progression in open-angle glaucoma (OAG) in the presence of MvD in different locations.

METHODS

A total of 181 consecutive OAG eyes (follow-up 7.3 ± 4.0 years), which demonstrated peripapillary choroidal MvD (defined as a focal capillary loss with no visible microvascular network in choroidal layer) on optical coherence tomography (OCT) angiography (OCTA), were divided based on the location of MvD. Structural progression was determined using trend-based analysis of the Guided Progression Analysis software of Cirrus OCT.

RESULTS

MvD was identified in the temporal quadrant in 110 eyes (temporal MvD; 60.5 ± 12.6 years), and in the inferior quadrant in 71 eyes (inferior MvD; 60.3 ± 11.1 years). After adjusting for age, average intraocular pressure (IOP) and baseline retinal nerve fibre layer (RNFL) thickness and visual field mean deviation, inferior MvD eyes showed faster rates of thinning in the inferior RNFL (mean (95% CI); -0.833 (-1.298 to -0.367)) compared to temporal MvD eyes (-0.144 (-0.496 to 0.207)) when long-term IOP fluctuation was larger than the median value (1.7 mmHg; P = 0.022). Long-term IOP fluctuations were independently associated with inferior RNFL thinning in eyes with inferior MvD (P = 0.002) but not in eyes with temporal MvD.

CONCLUSIONS

In OAG eyes, the rates of RNFL and GCIPL thinning were comparable regardless of MvD locations. However, inferior MvD is associated with faster RNFL and GCIPL thinning in the same quadrant when long-term IOP fluctuation is present. Structural progression in the presence of temporal MvD was less associated with IOP fluctuation.

Optic Nerve Head Morphology is Associated with the Initial Location of Structural Progression in Early Open Angle Glaucoma

PRCIS

Glaucoma eyes with a small cup-to-disk ratio (CDR) tend to show retinal nerve fiber layer progression earlier than ganglion cell-inner plexiform layer progression.

PURPOSE

To investigate the effects of clinical variables on the temporal relationship between macular ganglion cell-inner plexiform layer (mGCIPL) loss and peripapillary retinal nerve fiber layer (pRNFL) loss in glaucoma.

METHODS

This retrospective observational study used medical records of patients diagnosed with open angle glaucoma. Structural change was determined using guided progression analysis software of Cirrus optical coherence tomography. Based on the time of detection of pRNFL and mGCIPL changes, eyes showing progressive layer loss were categorized into the pRNFL-first and mGCIPL-first groups. The association between sites of layer thinning and clinical variables such as major retinal arterial angles and several optic disk measurements, including disk area, average CDR, and vertical CDR, were analyzed.

RESULTS

A total of 282 eyes were included in the study, of which 104 showed structural progression either in the mGCIPL or pRNFL. Out of these, 49 eyes showed the first progression in pRNFL, while 37 eyes showed the first progression in mGCIPL. The minimum mGCIPL thickness, pRNFL thickness, average CDR, vertical CDR, and location of progression were significantly different between the 2 groups ( P =0.041, P =0.034, P =0.015, P <0.001, and P <0.001, respectively). In multivariate analysis, average CDR and vertical CDR were significantly associated with the progression site ( P =0.033 and P =0.006, respectively). The structural changes in the inferoinferior area and the superior vulnerability zone were significantly associated with RNFL-first progression ( P <0.001 for both).

CONCLUSION

The location of layer loss and CDR are related to the layer where loss is first detected (either pRNFL or mGCIPL) in open angle glaucoma.

Choriocapillaris and progressive ganglion cell-inner plexiform layer loss in non-glaucomatous eyes

AIMS

To explore the relationship between choriocapillaris (CC) flow deficit percentage (FD%) and ganglion cell-inner plexiform layer (GCIPL) thickness in a population-based sample of non-glaucomatous eyes.

METHODS

This is a longitudinal cohort study and prospective cross-sectional study. Non-glaucoma Chinese subjects aged 18 years or older were enrolled. All participants underwent a detailed ophthalmic examination, including swept-source optical coherence tomography (SS-OCT) and SS-OCT angiography. Average, inner average, outer average and nine Early Treatment Diabetic Retinopathy Study sub-regions of GCIPL thickness and CC FD% were measured. The correlation between CC FD% and GCIPL was assessed using a linear regression model, and the relationship between the rate of change of GCIPL thickness and CC FD% was further validated in a 2year longitudinal study.

RESULTS

In the cross-sectional study including 3514 participants (3514 non-glaucoma eyes), a higher CC FD% was significantly associated with a thinner GCIPL (β=-0.32; 95% CI -0.43 to -0.21; p<0.001). Further, in a longitudinal study (453 eyes of 453 participants), a faster increase in CC FD% was found to be significantly associated with a faster decrease in GCIPL thickness (β=-0.10; 95% CI -0.17 to -0.03; p=0.004) after adjusting for age, sex, axial length and image quality score.

CONCLUSIONS

This is the first time to show that CC FD% and GCIPL thickness were correlated in both cross-sectional and longitudinal studies of non-glaucomatous individuals, which may potentially provide further insights on the role of CC perfusion in glaucoma development and progression.

Distribution of the cysteinyl leukotriene system components in the human, rat and mouse eye

The cysteinyl leukotrienes (CysLTs) have important functions in the regulation of inflammation and cellular stress. Blocking the CysLT receptors (CysLTRs) with specific antagonists is beneficial against progression of retinopathies (e.g. diabetic retinopathy, wet AMD). However, the exact cellular localization of the CysLTRs and their endogenous ligands in the eye have not been elucidated in detail yet. It is also not known whether the expression patterns differ between humans and animal models. Therefore, the present study aimed to describe and compare the distribution of two important enzymes in CysLT biosynthesis, 5-lipoxygenase (5-LOX) and 5-lipoxygenase-activating protein (FLAP), and of CysLTR1 and CysLTR2 in healthy human, rat and mouse eyes. Human donor eyes (n = 10) and eyes from adult Sprague Dawley rats (n = 5) and CD1 mice (n = 8) of both sexes were collected. The eyes were fixed in 4% paraformaldehyde and cross-sections were investigated by immunofluorescence with specific antibodies against 5-LOX, FLAP (human tissue only), CysLTR1 and CysLTR2. Flat-mounts of the human choroid were prepared and processed similarly. Expression patterns were assessed and semiquantitatively evaluated using a confocal fluorescence microscope (LSM710, Zeiss). We observed so far unreported expression sites for CysLT system components in various ocular tissues. Overall, we detected expression of 5-LOX, CysLTR1 and CysLTR2 in the human, rat and mouse cornea, conjunctiva, iris, lens, ciliary body, retina and choroid. Importantly, expression profiles of CysLTR1 and CysLTR2 were highly similar between human and rodent eyes. FLAP was expressed in all human ocular tissues except the lens. Largely weak immunoreactivity of FLAP and 5-LOX was observed in a few, yet unidentified, cells of diverse ocular tissues, indicating low levels of CysLT biosynthesis in healthy eyes. CysLTR1 was predominantly detected in ocular epithelial cells, supporting the involvement of CysLTR1 in stress and immune responses. CysLTR2 was predominantly expressed in neuronal structures, suggesting neuromodulatory roles of CysLTR2 in the eye and revealing disparate functions of CysLTRs in ocular tissues. Taken together, we provide a comprehensive protein expression atlas of CysLT system components in the human and rodent eye. While the current study is purely descriptive and therefore does not allow significant functional conclusions yet, it represents an important basis for future studies in diseased ocular tissues in which distribution patterns or expression levels of the CysLT system might be altered. Furthermore, this is the first comprehensive study to elucidate expression patterns of CysLT system components in human and animal models that will help to identify and understand functions of the system as well as mechanisms of action of potential CysLTR ligands in the eye.

Retinal Neurodegeneration and Visual Acuity Decline in Patients with Chronic Kidney Disease

INTRODUCTION

Chronic kidney disease (CKD) has been associated with accelerated retinal neurodegeneration. The purpose of this study is to evaluate the association between retinal neurodegeneration and the best-corrected visual acuity (BCVA) decline in patients with CKD.

METHODS

Post hoc analysis of two prospective studies. Patients with CKD stage ≥ 3 were enrolled. Macular thickness, peripapillary retinal nerve fiber layer (pRNFL) thickness, and macular ganglion cell complex (GCC) thickness were measured by optical coherence tomography. Eyes were classified into three groups: Group 1, no GCC defect; Group 2, GCC defect confined to parafoveal area; and Group 3, GCC defects extending beyond the parafoveal area. Each group was matched for age, sex, axial length, lens status, and cataract grading.

RESULTS

A total of 120 eyes (40 eyes in each group) from 120 patients (age 63.0 ± 10.3 years) were included. The logMAR BCVA was 0.076 ± 0.101, 0.100 ± 0.127, and 0.196 ± 0.191 in Group 1, 2, and 3, respectively. Group 3, but not Group 2, had a significantly worse BCVA than Group 1. In simple linear regression, parafoveal inner retinal thickness, pRNFL thickness, presence of pRNFL defect, GCC thickness, GCC global loss volume, GCC focal loss volume, and GCC defect extending beyond parafoveal area were associated with BCVA. Central subfield retinal thickness (CRT), parafoveal full retinal thickness, and parafoveal outer retinal thickness were not associated with BCVA. In backward stepwise linear regression, age and GCC defects extending beyond the parafoveal area were factors associated with BCVA. Moreover, GCC defect extending beyond parafoveal area was connected with worse BCVA in both phakic and pseudophakic subgroups.

CONCLUSIONS

GCC defect extending beyond parafoveal area could be an independent biomarker associated with decreased BCVA in patients with CKD. However, macular thinning measured by CRT or parafoveal full retinal thickness might have low discriminative power in determining BCVA.

Physical Activity Is Associated With Macular Thickness: A Multi-Cohort Observational Study

Purpose

To assess the association between physical activity and spectral-domain optical coherence tomography (SD-OCT)-measured rates of macular thinning in an adult population with primary open-angle glaucoma.

Methods

The correlation between accelerometer-measured physical activity and rates of macular ganglion cell-inner plexiform layer (GCIPL) thinning was measured in 735 eyes from 388 participants of the Progression Risk of Glaucoma: RElevant SNPs with Significant Association (PROGRESSA) study. The association between accelerometer-measured physical activity and cross-sectional SD-OCT macular thickness was then assessed in 8862 eyes from 6152 participants available for analysis in the UK Biobank who had SD-OCT, ophthalmic, comorbidity, and demographic data.

Results

Greater physical activity was associated with slower rates of macular GCIPL thinning in the PROGRESSA study (beta = 0.07 µm/y/SD; 95% confidence interval [CI], 0.03-0.13; P = 0.003) after adjustment for ophthalmic, demographic and systemic predictors of macular thinning. This association persisted in subanalyses of participants characterized as glaucoma suspects (beta = 0.09 µm/y/SD; 95% CI, 0.03-0.15; P = 0.005). Participants in the upper tertile (greater than 10,524 steps/d) exhibited a 0.22-µm/y slower rate of macular GCIPL thinning than participants in the lower tertile (fewer than 6925 steps/d): -0.40 ± 0.46 µm/y versus -0.62 ± 0.55 µm/y (P = 0.003). Both time spent doing moderate/vigorous activity and mean daily active calories were positively correlated with rate of macular GCIPL thinning (moderate/vigorous activity: beta = 0.06 µm/y/SD; 95% CI, 0.01-0.105; P = 0.018; active calories: beta = 0.06 µm/y/SD; 95% CI, 0.006-0.114; P = 0.032). Analysis among 8862 eyes from the UK Biobank revealed a positive association between physical activity and cross-sectional total macular thickness (beta = 0.8 µm/SD; 95% CI, 0.47-1.14; P < 0.001).

Conclusions

These results highlight the potential neuroprotective benefits of exercise on the human retina.

Association Between Body Mass Index and Primary Open Angle Glaucoma in Three Cohorts

PURPOSE

To evaluate the relationship between body mass index (BMI) and glaucoma progression.

DESIGN

Multicohort observational study.

METHODS

This study combined a retrospective longitudinal analysis of suspect and early manifest primary open angle glaucoma cases from the Progression Risk of Glaucoma: RElevant SNPs with Significant Association (PROGRESSA) study with 2 replication cohorts from the UK Biobank and the Canadian Longitudinal Study of Ageing (CLSA). In the PROGRESSA study, multivariate analysis correlated BMI with longitudinal visual field progression in 471 participants. The BMI was then associated with glaucoma diagnosis and cross-sectional vertical cup-disc ratio (VCDR) measurements in the UK Biobank, and finally prospectively associated with longitudinal change in VCDR in the CLSA study.

RESULTS

In the PROGRESSA study, a lower BMI conferred a faster rate of visual field progression (mean duration of monitoring (5.28 ± 1.80 years (10.6 ± 3.59 visits) (β 0.04 dB/year/SD95% CI [0.005, 0.069]; P = .013). In the UK Biobank, a 1 standard deviation lower BMI was associated with a worse cross-sectional VCDR (β -0.048/SD 95% CI [-0.056, 0.96]; P < .001) and a 10% greater likelihood of glaucoma diagnosis, as per specialist grading of retinal fundus imaging (OR 0.90 95% CI [0.84, 0.98]; P = .011). Similarly, a lower BMI was associated with a greater risk of glaucoma diagnosis as per International Classification of Disease data (OR 0.94/SD; 95% CI [0.91, 0.98]; P = .002). Body mass index was also positively correlated with intraocular pressure (β 0.11/SD; 95% CI [0.06, 0.15]; P < .001). Finally, a lower BMI was then associated with greater VCDR change in the CLSA (β -0.007/SD; 95% CI [-0.01, -0.001]; P = .023).

CONCLUSIONS

Body mass index correlated with longitudinal and cross-sectional glaucomatous outcomes. This supports previous work illustrating a correlation between BMI and glaucoma.

Vasculature-function relationship in open-angle glaucomatous eyes with a choroidal microvasculature dropout

Identifying biomarkers associated with functional impairment is important in monitoring glaucoma patients. This retrospective cross-sectional study investigated the vasculature-function relationship in open-angle glaucoma (OAG) eyes with choroidal microvasculature dropout (CMvD) versus in OAG eyes without. Optical coherence tomography (OCT) angiography-derived circumpapillary (cpVD) and macular vessel densities (mVD) were measured in 159 early-stage OAG eyes (mean deviation >  -6 dB) in accordance with the presence or not of a CMvD. OCT-derived circumpapillary retinal nerve fibre layer thickness (cpRNFLT) and macular ganglion cell-inner plexiform layer thicknesses (mGCIPLT) were also measured as reference standards. The vasculature (cpVD and mVD)-function [24-2 visual field mean sensitivity (VFMS) and central 10° VFMS (cVFMS)] and structure (cpRNFLT and mGCIPLT)-function (24-2 VFMS and cVFMS) relationships were compared using global and sectoral maps between OAG eyes with (CMvD+) and without CMvD (CMvD-). The CMvD+ eyes showed significantly steeper cpVD-24-2 VFMS and mVD-cVFMS correlations (P < 0.05). In contrast, there were no significant differences in the cpRNFLT-24-2 VFMS and mGCIPLT-cVFMS relationships between the two groups (P > 0.05). In conclusion, OAG eyes with a CMvD have significantly stronger vasculature-function relationships than eyes without. Vessel density parameters may be useful biomarkers of disease progression in early-stage OAG patients with a CMvD.

Systemic Arterial Stiffness Is Associated With Structural Progression in Early Open-Angle Glaucoma

Purpose

The purpose was to identify association between systemic arterial stiffness predicted by brachial-ankle pulse wave velocity (PWV) and initial location of structural progression in early open-angle glaucoma.

Methods

Patients with early open-angle glaucoma who underwent PWV measurements were subjected to a retrospective review of medical records. A total of 160 eyes of 160 patients were subjected to analyses. Patients were categorized into three PWV groups. Structural progression was determined using event-based analysis of the Guided Progression Analysis software of Cirrus optical coherence tomography.

Results

Thirty-eight patients had a PWV of 1400 cm/s or less on both the left and right sides (low PWV, 39.5% females, 53.9 ± 8.8 years old), and 46 patients showed a PWV of 1800 cm/s or more on either side (high PWV; 54.3% females, 71.3 ± 5.8 years old). The rest of the patients had an intermediate PWV (n = 76, 50.0% females, 59.8 ± 8.6 years old). Among patients who showed progression in 69.3 ± 41.5 months, macular ganglion cell–inner plexiform layer (mGCIPL) loss preceded peripapillary retinal nerve fiber layer (ppRNFL) loss in 86.7% of high PWV group (n = 15, 60.0% females, 70.0 ± 6.0 years old) in comparison with 26.7% of the low PWV group (P = 0.002). The PWV was significantly higher in patients whose structural progression was first observed at mGCIPL (1744.1 ± 347.7 cm/s) than patients whose initial location was ppRNFL (1452.0 ± 201.0 cm/s; P = 0.012). A high PWV was associated with increased likelihood of structural progression at mGCIPL (odds ratio, 7.484; 95% confidence interval, 1.212–49.196; P = 0.030) among patients who showed progression.

Conclusions

PWV is a significant predictor of the location of structural progression in open-angle glaucoma. Vascular insufficiency may be an important aspect in the pathogenesis of glaucoma.

Genetic Risk of Cardiovascular Disease Is Associated with Macular Ganglion Cell-Inner Plexiform Layer Thinning in an Early Glaucoma Cohort

PURPOSE

To evaluate the association between genetic risk for cardiovascular disease and retinal thinning in early glaucoma.

DESIGN

Prospective, observational genetic association study.

PARTICIPANTS

Multicohort study combining a cohort of patients with suspect and early manifest primary open-angle glaucoma (POAG), a cohort of patients with perimetric POAG, and an external normative control cohort.

METHODS

A cardiovascular disease genetic risk score was calculated for 828 participants from the Progression Risk of Glaucoma: Relevant SNPs [single nucleotide polymorphisms] with Significant Association (PROGRESSA) study. Participants were characterized as showing either predominantly macular ganglion cell-inner plexiform layer (GCIPL), predominantly peripapillary retinal nerve fiber layer (pRNFL) or equivalent macular GCIPL and pRNFL spectral-domain OCT thinning. The cardiovascular disease genetic risk scores for these groups were compared to an internal reference group of stable suspected glaucoma and of an external normative population. Replication was undertaken by comparing the phenotypes of participants from the Australia New Zealand Registry of Advanced Glaucoma (ANZRAG) with the normative control group.

MAIN OUTCOME MEASURES

Spectral-domain OCT and Humphrey Visual Field (HVF) change.

RESULTS

After accounting for age, sex, and intraocular pressure (IOP), participants with predominantly macular GCIPL thinning showed a higher cardiovascular disease genetic risk score than reference participants (odds ratio [OR], 1.76/standard deviation [SD]; 95% confidence interval [CI], 1.18-2.62; P = 0.005) and than normative participants (OR, 1.32/SD; 95% CI, 1.12-1.54; P = 0.002). This finding was replicated by comparing ANZRAG participants with predominantly macular GCIPL change with the normative population (OR, 1.39/SD; 95% CI, 1.05-1.83; P = 0.022). Review of HVF data identified that participants with paracentral visual field defects also demonstrated a higher cardiovascular disease genetic risk score than reference participants (OR, 1.85/SD; 95% CI, 1.16-2.97; P = 0.010). Participants with predominantly macular GCIPL thinning exhibited a higher vertical cup-to-disc ratio genetic risk score (OR, 1.48/SD; 95% CI, 1.24-1.76; P < 0.001), but an IOP genetic risk score (OR, 1.12/SD; 95% CI, 0.95-1.33; P = 0.179) comparable with that of the normative population.

CONCLUSIONS

This study highlighted the relationship between cardiovascular disease and retinal thinning in suspect and manifest glaucoma cases.

Factors Associated With Differences in the Initial Location of Structural Progression in Normal-Tension Glaucoma

PRCIS

Different clinical factors are associated with the location of the first structural progression in glaucoma.

PURPOSE

The aim was to investigate the underlying clinical parameters affecting the location of the initial structural progression of glaucoma in patients with normal-tension glaucoma (NTG).

METHODS

This retrospective study included 228 eyes of 228 patients with NTG. In total, 130 eyes of 130 patients demonstrated structural progression (as determined by event-based guided progression analysis using Cirrus HD-optical coherence tomography) in the peripapillary retinal nerve fiber layer (ppRNFL) or macular ganglion cell inner plexiform layer (mGCIPL). Depending on where the progression occurred first, it was defined as either ppRNFL first progression or mGCIPL first progression. Clinical parameters associated with each first progression were identified using logistic regression.

RESULTS

In total, 50 eyes showed ppRNFL first progression and 64 eyes showed mGCIPL first progression. ppRNFL first progression was significantly associated with female sex [odds ratio (OR)=5.705, P=0.015], lack of systemic hypertension (OR=0.199, P=0.014), disc hemorrhage (OR=4.188, P=0.029), higher mean intraocular pressure (OR=1.300, P=0.03), and lower pattern SD (OR=0.784, P=0.028). In contrast, male sex (OR=0.450, P=0.043), lower central corneal thickness (OR=0.987, P=0.032), higher intraocular pressure fluctuation (OR=1.753, P=0.047), lower systolic blood pressure fluctuation (OR=0.839, P=0.002), and higher diastolic blood pressure fluctuation (OR=1.208, P=0.015) were significantly associated with mGCIPL first progression.

CONCLUSIONS

Different clinical factors were associated with the initial site of structural glaucoma progression in patients with NTG depending on its peripapillary or macular location, and these findings suggest possible differences in underlying mechanisms of glaucoma damage.

Visual fields and optical coherence tomography (OCT) in neuro-ophthalmology: Structure-function correlation

Visual field (VF) testing is an essential component of the neurological examination. The differential diagnosis of VF defects depends on relating this measure of afferent visual function to the structure of the visual pathway and optical coherence tomography (OCT) is an invaluable tool for detailed structural evaluation of the optic nerve and retina. This review describes the ways in which interpretation of VF and OCT can be used together to increase the accuracy of the localization of lesions along the visual pathway. Lesions of the anterior visual pathway (originating in ganglion cells or nerve fibre layer of the retina or optic nerve) will typically produce defects that respect the horizontal midline, reflecting the arcuate path of the ganglion cell axons as they travel to the optic nerve. OCT of peripapillary retinal nerve fibre layer and ganglion cell complex (GCC) will typically demonstrate irreversible thinning in compressive and demyelinating lesions affecting anterior visual pathway. Chiasmal lesions produce highly localizable VF defects (junctional scotoma and bitemporal hemianopia) which correspond to the thinning of nasal portion of GCC. Lesions of the optic tract result in incongruous homonymous hemianopia on VF with corresponding hemianopic thinning on GCC developing within months. Lesions affecting optic radiations usually produce more congruous homonymous VF defects and can also produce homonymous thinning on GCC, however, this takes much longer to develop as trans-synaptic degeneration at the lateral geniculate body must occur.

U-Shaped Effect of Blood Pressure on Structural OCT Metrics and Retinal Perfusion in Ophthalmologically Healthy Subjects

Purpose

We wanted to investigate the association of blood pressure (BP) status with the ganglion cell-inner plexiform layer (GCIPL) and retinal nerve fiber layer (RNFL) thickness of nonglaucomatous eyes and to elucidate whether this effect is related to vascular metrics proxying retinal perfusion.

Methods

For this case-control study, we prospectively included 96 eyes of 96 healthy subjects (age 50–65) from a large-scale population-based cohort in the northern Netherlands (n = 167,000) and allocated them to four groups (low BP, normal BP [controls], treated arterial hypertension [AHT], untreated AHT). We measured macular GCIPL and RNFL (mRNFL) and peripapillary RNFL (pRNFL) thicknesses with optical coherence tomography (OCT). We estimated retinal blood flow (RBF), retinal vascular resistance (RVR), and autoregulatory reserve (AR) from quantitative OCT-angiography, fundus imaging, BP, and intraocular pressure. We compared structural and vascular metrics across groups and performed mediation analysis.

Results

Compared to controls, GCIPL was thinner in the low BP group (P = 0.013), treated hypertensives (P = 0.007), and untreated hypertensives (P = 0.007). Treated hypertensives exhibited the thinnest mRNFL (P = 0.001), temporal pRNFL (P = 0.045), and inferior pRNFL (P = 0.034). The association of GCIPL thickness with BP was mediated by RBF within the combined low BP group and controls (P = 0.003), by RVR and AR within the combined treated hypertensives and controls (P = 0.001, P = 0.032), and by RVR within the combined untreated antihypertensives and controls (P = 0.022).

Conclusions

Inner retinal thinning was associated with both tails of the BP distribution and with ineffective autoregulation. Longitudinal studies could clarify whether these defects can explain the reported glaucomatous predisposition of these population groups.

Clinical Use of PanoMap for Glaucoma: Frequently Damaged Areas in Early Glaucoma

PRCIS

Recognizing the shortcomings of poor consistency of the fovea-disc relationship at different time points and comparing PanoMaps may well facilitate the understanding of the spatial relationship between parapapillary and macular areas in glaucoma.

PURPOSE

The aims of this study are to analyze the spatial distribution of the frequently damaged areas in early glaucoma, compare the patterns between nonprogressors and progressors using the combined wide-field parapapillary and macular deviation maps (PanoMap), and to evaluate the consistency of the fovea-disc relationship in PanoMap. The fovea-disc distance (FDD) and fovea-disc axis (FDA) were compared at baseline and at the last follow-up.

MATERIALS AND METHODS

In total, 118 patients with early glaucoma and a minimum follow-up period of 3 years were included in this retrospective observational study. The pattern of structural changes was evaluated by averaging the PanoMaps of the enrolled patients at baseline and last follow-up. Longitudinal comparison of the FDD and FDA was performed at baseline and the last follow-up. Patients were divided into nonprogressor (n=44) and progressor (n=74), and the patterns of glaucoma progression in PanoMaps were compared between them.

RESULTS

At baseline, the glaucomatous damage was found more frequently in the macular compared with the parapapillary area. The spatial distribution of frequently damaged areas was similar between the nonprogressor and progressor. At the last follow-up, compared with the baseline structural change on the PanoMap, the progressive structural changes extended toward the fovea at both the parapapillary and macular areas in the progressor. The FDD and FDA were significantly different between the baseline and the last follow-up.

CONCLUSIONS

The PanoMaps showed a clear spatial distribution of early glaucomatous changes, indicating that the damaged area was frequently observed in the macular area. As the consistency of the fovea-disc relationship in PanoMaps was not excellent, this aspect should be considered when interpreting the PanoMap.

Clinical Predictors of the Region of First Structural Progression in Early Normal-tension Glaucoma

PURPOSE

This study aimed to compare the clinical characteristics of patients who showed structural progression in the peripapillary retinal nerve fiber layer (RNFL) first against those who showed progression in the macular ganglion cell-inner plexiform layer (GCIPL) first and to investigate clinical parameters that help determine whether a patient exhibits RNFL or GCIPL damage first.

METHODS

A retrospective review of medical records of patients diagnosed with early-stage normal-tension glaucoma was performed. All eyes underwent intraocular pressure measurement with Goldmann applanation tonometer, standard automated perimetry, and Cirrus optical coherence tomography at 6-month intervals. Structural progression was determined using the Guided Progression Analysis software. Blood pressure was measured at each visit.

RESULTS

Forty-one eyes of 41 patients (mean age, 52.6 ± 16.7 years) were included in the study. In 21 eyes, structural progression was first detected in the RNFL at 54.2 ± 14.8 months, while structural progression was first observed at the macular GCIPL at 40.5 ± 11.0 months in 20 eyes. The mean intraocular pressure following treatment was 13.1 ± 1.8 mmHg for the RNFL progression first group and 13.4 ± 1.8 mmHg for the GCIPL progression first group (p = 0.514). The GCIPL progression first group was older (p = 0.008) and had thinner RNFL at baseline (p = 0.001). The logistic regression analyses indicated that both age and follow-up duration until first progression predicted the region of structural progression (odds ratio, 1.051; 95% confidence interval, 1.001-1.105; p = 0.046 for age; odds ratio, 0.912; 95% confidence interval, 0.840-0.991; p = 0.029 for time until progression).

CONCLUSIONS

Age of glaucoma patients and time until progression are associated with the region of the first structural progression in normal-tension glaucoma. Further studies exploring the association between glaucomatous progression and the location of damage are needed.

Correlation of Ocular Biometric Parameters and Macular Ganglion Cell Layer in Normal Eyes

PURPOSE

To determine the association between ocular biometric parameters and macular ganglion cell layer (MGCL) thickness in normal eyes.

METHODS

This observational cohort study was conducted with 76 eyes of 76 healthy subjects. Keratometry, pachymetry, corneal volume, iridocorneal angle were measured with Sirius (CSO, Florence, Italy); axial length, anterior chamber depth, anterior chamber volume, corneal diameter were measured with IOL Master (Carl Zeiss Meditec, Dublin, California). For all participants, serial horizontal Spectralis Domain Optical Coherence Tomography (SD-OCT, Heidelberg Engineering, GmbH, Dossenheim, Germany) scans of the macula and peripapillary retinal nerve fiber layer (RNFL) analysis were obtained using SD-OCT. The relationship between numerical variables was given by Pearson correlation coefficient.

RESULTS

The mean age of the subjects was 36.3 ± 11.9 years (between 19 and 70 y). Fifty-one patients were female (67.1%) and twenty-five patients were male (32.9%). MGCL was found to be correlated with anterior chamber depth, anterior chamber volume, iridocorneal angle, axial length and white to white (p = .015 r = 0.594, p = .002 r = 0.365, p = .013 r = 0.299, p = .004 r = 0.335, p = .013 r = 0.289, respectively). In addition, MGCL was correlated positively with the mean global and superotemporal RNFL (p ≤ 0.005). However, neither central corneal thickness nor keratometry values were found to be correlated with MGCL.

CONCLUSION

The results of this study showed that MGCL thickness is affected by ocular biometric parameters. Therefore, these parameters should be taken into consideration when interpreting MGCL thickness measurements in the diagnosis of glaucoma.

Detection of Primary Angle Closure Glaucoma Progression by Optical Coherence Tomography

PURPOSE

To compare the role of spectral-domain optical coherence tomography (SD-OCT) in regard to retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) assessment in the detection of primary angle-closure glaucoma (PACG) and primary open-angle glaucoma (POAG) progression.

MATERIALS AND METHODS

In the prospective study, 131 subjects with PACG and POAG were examined during 72 months with follow-up visits every 6 months. Visual field (VF) progression was detected using the Guided Progression Analysis (GPA) of the Humphrey visual field analyzer and structural change using SD-OCT while a significant negative trend for the RNFL and GCC was gauged. The diagnostic accuracy of RNFL and GCC thinning in the detection of glaucoma progression was compared between PACG and POAG eyes using the Kaplan-Meier method with the calculation of the log-rank test.

RESULTS

Progression was detected in 57% of eyes with POAG and 59% of eyes with PACG. The rate of thinning of RNFL (-2.95±1.85 μm/y) and GCC (-3.22±2.96 μm/y) was significantly higher in PACG progression eyes compared with POAG [-1.64±2.00 μm/y (P=0.018) and -1.74±2.05 μm/y (P=0.046), respectively]. The progression was associated with initial pattern standard deviation in both glaucoma subtypes, while only in PACG-with long-term intraocular pressure fluctuations (cutoff >5.2 mm Hg) and lens thickness (cutoff >4.92 mm), and only in POAG-with initial focal loss volume of GCC (cutoff >1.5%).In PACG, the rate of the visual function deterioration correlated with GCC thinning rate (r=0.330, P=0.027), but not with the RNFL thinning rate (r=-0.010, P=0.79), while in POAG, it was significant for both RNFL thinning (r=0.296, P=0.039) and GCC thinning (r=0.359, P=0.011). In PACG patients with progressive GCC thinning, functional progression was detected earlier (log-rank test P≤0.001) than in patients with progressive RNFL thinning (log-rank test P=0.457), while for POAG, these results were P=0.012 and ≤0.001 for GCC and RNFL thinning, respectively.

CONCLUSIONS

SD-OCT plays an important role in detecting PACG progression. In contrast to POAG, GCC thinning predicted functional loss better than RNFL thinning in PACG.

Temporal Raphe Sign in Elderly Patients With Large Optic Disc Cupping: Its Evaluation as a Predictive Factor for Glaucoma Conversion

PURPOSE

To determine baseline clinical features associated with conversion to glaucoma in elderly patients with large optic-disc cupping.

DESIGN

Retrospective cohort study.

METHODS

Seventy-two eyes of 72 untreated elderly (≥65-year-old) patients with large vertical cup-to-disc ratio (CDR ≥0.7) and without any other glaucomatous findings were included. They had undergone a full ophthalmologic examination twice per year for at least 5 years. The optic nerve head (ONH), peripapillary retinal nerve fiber layer (RNFL), and macular ganglion cell-inner plexiform layer (GCIPL) were imaged with Cirrus high-definition optical coherence tomography (OCT). Presence of temporal raphe sign on the OCT's GCIPL thickness map was assessed as one of the morphologic factors. Conversion to normal-tension glaucoma (NTG) was defined as structural or functional deterioration on either red-free RNFL photography or standard automated perimetry, respectively. The utility of the baseline factors associated with conversion to NTG were identified.

RESULTS

During the 5.5-year follow-up, 19 eyes (26.4%) converted to NTG. There were no significant differences in demographics, systemic factors, intraocular pressure factors, or OCT parameters between the nonconverters and converters. Interestingly, the temporal raphe sign was observed in the converters (18/19, 94.7%) much more frequently than in the nonconverters (3/53, 5.7%, P < .001) at baseline. A Cox proportional hazards model indicated the significant influences of temporal raphe sign positivity (hazard ratio 6.823, 95% confidence interval 2.574, 18.088, P < .001) on conversion to NTG.

CONCLUSIONS

In elderly subjects with large CDR, temporal raphe sign positivity on the baseline macular GCIPL thickness map was associated with faster conversion to NTG.

Vulnerability Zone of Glaucoma Progression in Combined Wide-field Optical Coherence Tomography Event-based Progression Analysis

Purpose

To investigate the spatial characteristics and patterns of structural progression using the combined retinal nerve fiber layer (RNFL) and ganglion cell–inner plexiform layer event-based progression analysis feature provided by the Guided Progression Analysis (GPA) software of spectral-domain optical coherence tomography.

Methods

In this retrospective observational study, we evaluated 89 patients with open-angle glaucoma showing clinically confirmed structural progression within a minimum follow-up period of 3 years. For each eye, the RNFL and ganglion cell–inner plexiform layer GPA data were extracted from serial spectral-domain optical coherence tomography (HD-OCT 4000, Carl Zeiss Meditec, Inc., Dublin, CA) data from 2012 to 2017 (available in commercial report). A combined wide-field GPA map was merged using vascular landmark-guided superimposition of RNFL and ganglion cell–inner plexiform layer GPA event-based progression maps onto the RNFL image (resulting in the GPA PanoMaps: proposed in this study). The pattern of progressive structural changes was evaluated by comparing the baseline combined wide-field OCT deviation maps (PanoMap deviation maps: available in commercial report) and GPA PanoMaps at the time the first progression was detected and the GPA PanoMaps at the last follow-up. Spatial characteristics and patterns of glaucoma structural progression on GPA PanoMaps were evaluated.

Results

Progressive structural progression was detected most frequently at the macular vulnerability zone (MVZ), with the peripapillary and macular progression being well-correlated spatially. Compared with the baseline structural change on PanoMap, the progressive structural changes extended toward the fovea at both the peripapillary and macular areas. A spatial difference was observed between the areas where structural damage was frequently found on PanoMap (peripapillary inferoinferior sector and macular MVZ) and areas where progression was frequently found on GPA PanoMap (peripapillary and macular MVZ).

Conclusions

The patterns of progressive glaucomatous structural changes in both the peripapillary and macular areas were confirmed on the combined wide-field GPA map (GPA PanoMap). An analysis of the progression pattern using the GPA PanoMap facilitates the understanding of the spatial relation between the peripapillary and macular areas in glaucoma.

Dual-input convolutional neural network for glaucoma diagnosis using spectral-domain optical coherence tomography

BACKGROUND/AIMS

To evaluate, with spectral-domain optical coherence tomography (SD-OCT), the glaucoma-diagnostic ability of a deep-learning classifier.

METHODS

A total of 777 Cirrus high-definition SD-OCT image sets of the retinal nerve fibre layer (RNFL) and ganglion cell-inner plexiform layer (GCIPL) of 315 normal subjects, 219 patients with early-stage primary open-angle glaucoma (POAG) and 243 patients with moderate-to-severe-stage POAG were aggregated. The image sets were divided into a training data set (252 normal, 174 early POAG and 195 moderate-to-severe POAG) and a test data set (63 normal, 45 early POAG and 48 moderate-to-severe POAG). The visual geometry group (VGG16)-based dual-input convolutional neural network (DICNN) was adopted for the glaucoma diagnoses. Unlike other networks, the DICNN structure takes two images (both RNFL and GCIPL) as inputs. The glaucoma-diagnostic ability was computed according to both accuracy and area under the receiver operating characteristic curve (AUC).

RESULTS

For the test data set, DICNN could distinguish between patients with glaucoma and normal subjects accurately (accuracy=92.793%, AUC=0.957 (95% CI 0.943 to 0.966), sensitivity=0.896 (95% CI 0.896 to 0.917), specificity=0.952 (95% CI 0.921 to 0.952)). For distinguishing between patients with early-stage glaucoma and normal subjects, DICNN's diagnostic ability (accuracy=85.185%, AUC=0.869 (95% CI 0.825 to 0.879), sensitivity=0.921 (95% CI 0.813 to 0.905), specificity=0.756 (95% CI 0.610 to 0.790)]) was higher than convolutional neural network algorithms that trained with RNFL or GCIPL separately.

CONCLUSION

The deep-learning algorithm using SD-OCT can distinguish normal subjects not only from established patients with glaucoma but also from patients with early-stage glaucoma. The deep-learning model with DICNN, as trained by both RNFL and GCIPL thickness map data, showed a high diagnostic ability for discriminatingpatients with early-stage glaucoma from normal subjects.

Pre-perimetric Open Angle Glaucoma with Young Age of Onset: Natural Clinical Course and Risk Factors for Progression

PURPOSE

To investigate the natural clinical course of more than 5 years and the risk factors of progression in patients with pre-perimetric open angle glaucoma (OAG) of "young age of onset (under age 40)" without treatment.

DESIGN

Retrospective observational case series.

METHODS

Optic disc photography, red-free retinal nerve fiber layer (RNFL) photography, optical coherence tomography, and visual field (VF) examinations were performed every 6 months. Glaucoma progression was defined as structural or functional deterioration. A linear mixed-effects model was used to estimate the rate of structural and functional changes. Kaplan-Meier survival analysis and log-rank testing were used to compare survival experiences, and Cox proportional hazards modeling was performed to identify risk factors for glaucoma progression.

RESULTS

Of the 98 eyes of 98 patients (mean age, 30.6 years old), glaucoma progression was detected in 42 eyes (42.9%). The rate of average RNFL thickness thinning was -0.46 ± 0.50 μm/y, and the mean deviation (MD) change was -0.03 ± 0.13 dB/y. The glaucoma progression probability at 5 years was 39% by structural criteria and 5% by functional criteria. Older age at diagnosis (P = .004), presence of temporal raphe sign (horizontal straight line on macular ganglion cell-inner plexiform layer thickness map) (P = .011), lamina pore visibility (P = .034), and greater pattern standard deviation (P = .005) were significant factors for glaucoma progression.

CONCLUSIONS

In untreated pre-perimetric OAG patients with a "young age of onset" condition, the estimated MD slope for the disease course of more than 5 years was -0.03 dB/y, and the average RNFL thinning rate was -0.46 μm/y. The predictors for progression were structural parameters of temporal raphe sign, lamina pore visibility, and functional parameter of pattern standard deviation.

Cardiovascular Disease Predicts Structural and Functional Progression in Early Glaucoma

PURPOSE

To investigate the association between cardiovascular disease and baseline structural defects and disease progression in glaucoma.

DESIGN

Prospective, longitudinal study of preperimetric and perimetric glaucoma.

PARTICIPANTS

Two thousand six hundred twenty-eight eyes from 1314 participants recruited to the Progression Risk of Glaucoma: Relevant SNPs with Significant Association (PROGRESSA) study were evaluated for baseline and longitudinal structural thinning using spectral-domain OCT and for visual field progression on Humphrey visual field (HVF) assessment.

METHODS

Patients were classified as either predominantly macula ganglion cell-inner plexiform layer (mGCIPL), predominantly peripapillary retinal nerve fiber layer (pRNFL), or both mGCIPL and pRNFL structural change at enrollment, and then evaluated for longitudinal OCT or HVF progression. Cardiovascular disease and medication characteristics of the participants were compared with a reference group of stable patients.

MAIN OUTCOME MEASURES

OCT and HVF baseline status and longitudinal progression.

RESULTS

After accounting for age and cardiovascular characteristics, patients with predominantly mGCIPL thinning at baseline showed a higher prevalence of hypertension (odds ratio [OR], 2.70; 95% confidence interval [CI], 1.66-4.41; P < 0.001), antihypertensive use (OR, 2.03; 95% CI, 1.20-3.46; P = 0.008), and statin use (OR, 1.98; 95% CI, 1.07-3.66; P = 0.029) than reference patients. Patients with predominantly pRNFL thinning exhibited a comparable prevalence of cardiovascular disease or medication with reference patients. Review of longitudinal OCT and HVF data (mean follow-up, 5.34 ± 1.29 years) showed that hypertension was associated with an increased risk of both OCT (OR, 1.79; 95% CI, 1.17-2.75; P = 0.006) and HVF progression (OR, 1.92; 95% CI, 1.18-3.15; P = 0.013). A 1-standard deviation (approximately 21 mmHg) increase in systolic blood pressure at baseline was associated with a greater risk of OCT progression (OR, 1.27; 95% CI, 1.01-1.63; P = 0.041) and HVF progression (OR, 1.32; 95% CI, 1.01-1.73; P = 0.043). The association between systolic blood pressure and structural progression was comparable to that observed between intraocular pressure and structural progression (OR, 1.30; 95% CI, 1.01-1.67; P = 0.039).

CONCLUSIONS

Cardiovascular disease is an important risk factor for glaucoma progression.

Evaluation of retina nerve fiber layer, ganglion cell-inner plexiform layer and lamina cribrosa in clinically unilateral exfoliative glaucoma

PURPOSE

To compare retinal nerve fiber layer (RNFL), ganglion cell-inner plexiform layer (GC-IPL), the lamina cribrosa depth (LCD) and thickness (LCT) in unilateral exfoliative glaucoma (EXG) patients with their fellow eyes without exfoliation and control eyes.

METHODS

This cross-sectional prospective single-center study consisted of 64 eyes of 32 patients with unilateral EXG and 35 eyes of controls. All subjects were examined with spectral domain optical coherence tomography for the RNFL and GC-IPL measurements. The LCD and LCT measurements were also obtained.

RESULTS

The RNFL measurements at all quadrants were statistically thinner in EXG eyes than those in their eyes without EXG and control eyes (p < 0.001 for average, superior, temporal and inferior; p = 0.004 for nasal). The EXG group had deeper LCD than their eyes without EXG and control eyes (p < 0.001, for both). The fellow eyes of EXG group had also deeper LCD than control eyes, with no statistical significance (p = 0.058). The mean LCT was thinner in EXG eyes compared to those in the eyes without EXG and control eyes (p < 0.001, for both). The eyes without EXG and control eyes had similar LCT (p = 0.293).

CONCLUSIONS

Recent developments in imaging technology give the clinician detailed structural information about optic nerve head and retina such as GC-IPL, LCD and LCT. In addition to follow-up of RNFL changes, these new parameters may be useful in recognizing progression in EXG patients.

Quantitative analysis of retinal nerve fiber layer defect in early open-angle glaucoma with normal intraocular pressure

PURPOSE

To quantitatively analyze the topographic features of localized retinal nerve fiber layer (RNFL) defects according to baseline intraocular pressure (IOP) level in cases of early primary open-angle glaucoma (POAG).

STUDY DESIGN

Retrospective comparative study.

METHODS

POAG patients meeting the following conditions were consecutively included: (1) baseline office-hour diurnal IOP ≤ 21 mmHg, (2) 1 localized RNFL defect as observed on red-free fundus photography, and (3) corresponding visual field defect. Defects' approximations to the macula (angle α) and width (angle ß) as well as the angle between the disc long axis and the vertical meridian line (angle Ɣ) were measured on red-free fundus photography. The corrected angle α was calculated as the difference between angles α and Ɣ. The defect area's RNFL thickness was calculated by means of optical coherence tomography's Advanced Extraction analysis utility.

RESULTS

Comparative analysis was performed between 2 groups: 45 eyes of 45 patients with low-teen IOP (group A: highest IOP ≤ 15 mmHg) and 49 eyes of 49 patients with high-teen IOP (group B: lowest IOP > 15 mmHg). In group A, the mean baseline IOP was lower (12.9 ± 1.3 vs 17.1 ± 1.0 mmHg; P < .001), the corrected angle α was smaller (32.4 ± 15.1 vs 39.5 ± 13.1 degrees; P = .017), and the defect area's RNFL thickness was thinner (66.3 ± 16.8 vs 76.3 ± 14.9 μm; P = .003) than in group B; angle ß showed no intergroup difference (P = .230).

CONCLUSIONS

In POAG patients with low-teen IOP relative to those with high-teen IOP, localized RNFL defects were closer to the macula. In addition, the RNFL thickness of the defect area was markedly thinner.

Optical coherence tomography and optical coherence tomography angiography in glaucoma: diagnosis, progression, and correlation with functional tests

The present review will summarize the most updated findings with regards to optical coherence tomography and optical coherence tomography angiography in glaucoma, highlighting their clinical use for detection and monitoring of the disease, and their correlation to functional tests (such as visual field) widely employed in the asset of modern glaucoma clinics.

Traumatic optic neuropathy-associated progressive thinning of the retinal nerve fiber layer and ganglion cell complex: two case reports

Background

Traumatic optic neuropathy (TON) is a form of optic nerve injury that occurs secondary to trauma and is etiologically associated with acute axonal loss with severe vision loss. Here, we reported longitudinal changes in the peripapillary retinal nerve fiber layer (RNFL) and macular ganglion cell complex (GCC) using wide-field swept source optical coherence tomography (SS-OCT) in two cases of TON and identified the source of the damage.

Case presentation

(Case 1) A 65-year-old man was admitted to the hospital due to an injury in the right eye (OD) and was subsequently diagnosed with indirect TON. He was then treated with high-doses of intravenous steroids. Wide-field SS-OCT was performed at the baseline and after 1 day, 2 days, 1 week, 1 month, and 4 months. The wide-field deviation map detected thinning earlier in the macular GCC than in the peripapillary RNFL. (Case 2) A 63-year-old man was admitted to the hospital with a fractured left maxilla-zygomatic complex attributed to blunt-force trauma to the head and loss of vision in his left eye (OS). He was diagnosed with indirect TON and treated with high-doses of intravenous steroids. Wide-field SS-OCT was performed at the baseline and after 1 week, 2 weeks, 2 months 5 months, and 7 months. The wide-field deviation map detected thinning earlier in the peripapillary RNFL than in the macular GCC.

Conclusions

Wide-field SS-OCT facilitated the identification of various sequential progression patterns in patients with TON. Furthermore, the area in which the structural damage was first detected was seen differently in the peripapillary and macular deviation maps for each case. Thus, wide-field imaging, which includes the macular and peripapillary areas, are useful in monitoring TON.