Choroidal Thickness and Open-Angle Glaucoma: A Meta-Analysis and Systematic Review

A small disc size, a big challenge: effect of optic disc size on the correlation between peripapillary choroidal thickness, peripapillary retinal nerve fiber layer, and ganglion cell layer

PURPOSE

We aimed to analyze the effect of optic disc size on the correlation between the peripapillary choroid (PPC), peripapillary retinal nerve fiber layer (RNFL), and macular ganglion cell inner plexiform layer (MGCIPL) thicknesses in subjects with ocular hypertension (OHT) and primary open angle glaucoma (POAG).

METHODS

This study included 61 eyes with a disc area (DA) of ≤ 1.63 mm2, 92 eyes with a DA of 1.63-2.42 mm2, and 59 eyes with a DA of ≥ 2.42 mm2 in small disc, regular disc, and large disc groups, respectively. The swept-source optical coherence tomography scans of the PPC, RNFL, and MGCIPL were analyzed according to disc size.

RESULTS

The three groups did not significantly differ in RNFL or MGCIPL measurements, but the PPC measurement was statistically significantly higher in the small disc group and statistically significantly thinner in the large disc group. Most of the correlations observed between the RNFL and MGCIPL measurements and eye characteristics in the regular disc group were not detected in the small and large disc groups. While the RNFL and MGCIPL were well correlated in all disc size groups, the PPC did not correlate with the RNFL or MGCIPL in any of the groups.

CONCLUSIONS

Overall, the RNFL and MGCIPL measurements were consistent across all three disc sizes. While the PPC was thicker in small discs than in larger discs, it was not correlated with the RNFL or MGCIPL.

Choroidal thickness in juvenile open angle glaucoma: insights from a south asian case-control study

PURPOSE

The purpose of this study is to compare choroidal thickness in juvenile open angle glaucoma (JOAG) and healthy controls using spectral domain optical coherence tomography (SD-OCT) and study its correlations.

METHODS

In this case-control study, 56 eyes of 28 JOAG patients and an equal number of controls were recruited. SD-OCT was used to measure the choroidal thickness (ChT), in the macular region at 5 locations: subfoveal, 1500 µm and 3000 µm nasal and temporal to the foveal center, and in the peripapillary region at 6 locations: up to 1500 µm, nasal and temporal to the disc, respectively. The ChT and its correlations with age, intraocular pressure, cup-to-disc ratio, central corneal thickness, mean deviation, and axial length were studied.

RESULTS

The average macular ChT in JOAG was 306.30 ± 56.49 µm vs. 277.12 ± 64.68 µm in controls. The average peripapillary ChT in JOAG was 197.79 ± 44.05 µm vs. 187.24 ± 38.89 µm in controls. The average total ChT (p = 0.042), the average macular ChT (p = 0.022), the subfoveal ChT (p = 0.022), the ChT 1500 µm (p < 0.001), and 3000 µm temporal to the fovea (p = 0.002) were significantly thicker in the JOAG group. In the JOAG group, the average macular ChT had a significant negative correlation with age, whereas axial length was positively correlated with the average peripapillary ChT.

CONCLUSIONS

In this South Asian cohort of JOAG, the average total ChT, average macular ChT, subfoveal ChT, and ChT at 1500 µm, and 3000 µm temporal to the fovea were significantly thicker when compared to healthy controls.

Comparison of Peripapillary Choroidal Thickness Between Primary Open-angle Glaucoma, Normal Tension Glaucoma, and Normal Eyes: A Systematic Review and Meta-analysis

TOPIC

To investigate differences in peripapillary choroidal thickness (PPCT) between primary open-angle glaucoma (POAG), normal tension glaucoma (NTG), and healthy eyes, additionally comparing differences between POAG and NTG eyes.

CLINICAL RELEVANCE

Peripapillary choroidal thickness is a well-established OCT parameter in eyes with glaucoma and other ocular pathologies. The relationship between PPCT and glaucoma, if better understood, may facilitate the development of PPCT as a potential diagnostic and monitoring metric for glaucoma. In particular, there has yet to be a synthesis that directly compares PPCT between POAG eyes and NTG eyes.

METHODS

A comprehensive literature search was performed on PubMed, EMBASE, and Cochrane Library, identifying studies from inception to December 2022. We included studies that measured PPCT using OCT in POAG, NTG, and healthy eyes. Mean difference (MD) among groups was calculated. Statistical analysis was performed using R version 4.2.0. Risk of bias of included studies was assessed using the Newcastle Ottawa Scale (NOS).

RESULTS

Eighteen studies were included in this meta-analysis, with a pooled total of 935 healthy control eyes, 446 NTG eyes, and 934 POAG eyes. There was a significant reduction of PPCT in POAG eyes compared with healthy eyes [MD = -16.32; 95% confidence interval (CI) (-27.55 to -5.09)]. Reduction in PPCT was also significant in NTG eyes compared with healthy eyes [MD = -34.96; 95% CI (-49.97 to -19.95)]. NTG eyes had significantly reduced PPCT compared with POAG eyes [MD = -26.64; 95% CI (-49.00 to -4.28)].

CONCLUSIONS

Glaucomatous eyes appear to have significantly reduced PPCT compared with normal healthy eyes. In addition, PPCT in NTG eyes appear significantly thinner compared with that in POAG eyes.

FINANCIAL DISCLOSURE(S)

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

Simultaneous evaluation of iris area and subfoveal choroidal thickness in Fuchs uveitis syndrome

BACKGROUND/AIMS

To simultaneously evaluate iris area (IA) and subfoveal choroidal thickness (SFCT) in eyes with Fuchs Uveitis Syndrome (FUS).

METHODS

We prospectively recruited a case series of patients with FUS at our institution, simultaneously measuring IA with anterior segment spectral domain optical coherence tomography (SD-OCT) and SFCT with enhanced depth imaging optical coherence tomography (EDI-OCT). Iris images were analyzed by ImageJ software. We tested the differences in intereye IA and SFCT with the healthy eye (HE) using the Wilcoxon test, and clinical interpretation was controlled by intraclass correlation coefficient (ICC) between two masked specialists.

RESULTS

Sixteen patients with unilateral FUS were included. Six were female, and the age range was 37 to 67 (median age 48 years, IQR 41-60). ICC of 98.9%, with a lower confidence interval of 97%. Eyes with FUS had a significant thinning of the total iris median area (p < 0.002), restricted to the temporal and nasal areas compared to the HE (p < 0.01 and < 0.001, respectively). SFCT was also significantly thinner compared to the HE (p < 0.0001). A low correlation was found between iris and choroidal thinning in FUS eyes (rs = 0.21; p = 0.4).

CONCLUSIONS

This study found reduced iris area and subfoveal choroidal thickness in eyes with FUS compared to the normal fellow eye.

Peripapillary choroidal vascularity index and thickness in patients with systemic sclerosis

Introduction

Patients with systemic sclerosis (SSc) present an increased risk of developing glaucomatous optic neuropathy (GON). We investigated peripapillary choroidal parameters and peripapillary retinal nerve fiber layer (RNFL) thickness using spectral domain optical coherence tomography (SD-OCT) to determine the relationships of these factors with clinical variables.

Methods

A total of 33 patients with SSc were enrolled and compared to 40 controls. After obtaining circular scans around the optic disc, the global and quadrant peripapillary choroidal thickness (pCT) and RNFL thickness were measured. Additionally, the peripapillary choroidal vascularity index (pCVI), which allows for a quantitative analysis of the choroidal vasculature, was determined.

Results

No significant differences were found in pCT and RNFL thickness between patients with SSc and controls, or within SSc subtypes (diffuse cutaneous systemic sclerosis (dcSSc) compared to limited cutaneous systemic sclerosis (lcSSc)) (p > 0.05). The pCVI was significantly lower in patients with SSc than in control subjects (64.25 ± 1.94 vs.65.73 ± 2.12, p < 0.001).

Conclusion

Our results suggest that the statistically significant decrease in pCVI in patients with SSc compared to the control group is probably due to a decrease in the vascular layer, which would partially explain an increased risk of GON in patients with SSc.

Study of choroidal vasculature in open angle glaucoma patients

PURPOSE

To investigate the vessel density (VD) of the choriocapillary (CC) plexus in patients affected by preperimetric glaucoma (PPG), advanced glaucoma (AG) and in a healthy control group using Optical Coherence Tomography Angiography (OCTA) in order to clarify the pathogenetic mechanisms of this disease.

METHODS

In this prospective observational study, 19 eyes from 19 patients affected by preperimetric glaucoma (PPG) and 18 eyes from 18 patients affected by advanced glaucoma were studied from January 2022 to May 2022 at the University of Naples "Federico II". These patients had been compared with 20 eyes of 20 healthy subjects that represented the control group. All subjects underwent EDI-OCT to assess the subfoveal choroidal thickness (SFCT). OCTA was used to evaluate the vessel density (VD) of the CC in whole image in the studies groups.

RESULTS

The PPG and AG groups showed a statistically significant reduction in CC vessel density parameters with respect to controls (p < 0.001). Regarding EDI OCT results AG patients exhibited a statistically significant increase in the SFCT compared to healthy controls (p < 0.001). Whereas,no statistically significant difference was between the PPG groups and to healthy controls (p 0.851).

CONCLUSIONS

CC vessel density could represent a helpful and sensible biomarker to identify early choroidal microvascular changes in PPG and MCI in order to better understand the vascular pathophysiological mechanisms involved in glaucoma diseases.

Choroidal Thickness and Primary Open-Angle Glaucoma-A Narrative Review

The choroid provides the majority of blood flow to the ocular tissues and structures that facilitate the processes of retinal metabolism responsible for vision. Specifically, the choriocapillaris provides a structural network of small blood vessels that supplies the retinal ganglion cells and deep ocular tissues. Similar to retinal nerve fiber layer thickness, choroidal thickness (CT) has been suggested to represent a quantifiable health biomarker for choroidal tissues. Glaucoma is a disease with vascular contributions in its onset and progression. Despite its importance in maintaining ocular structure and vascular functionality, clinical assessments of choroidal tissues have been historically challenged by the inaccessibility of CT biomarker targets. The development of optical coherence tomography angiography and enhanced depth imaging created a framework for assessing CT and investigating its relationship to glaucomatous optic neuropathy onset and progression. Pilot studies on CT in glaucoma are conflicting-with those both in support of, and against, its clinical utility. Complicating the data are highly customized analysis methods, small sample sizes, heterogeneous patient groups, and a lack of properly designed controlled studies with CT as a primary outcome. Herein, we review the available data on CT and critically discuss its potential relevance and limitations in glaucoma disease management.

A comprehensive enhanced depth imaging spectral-domain optical coherence tomography analysis of pseudoexfoliation spectrum from non-glaucomatous to advanced stage glaucoma in the aspect of Bruch's membrane opening-minimum rim width

PURPOSE

To compare the correlations between lamina cribrosa (LC) and related structures with Bruch's membrane opening-minimum rim width (BMO-MRW) and retinal nerve fiber layer (RNFL) thickness in pseudoexfoliation syndrome (PXS) and different stages of pseudoexfoliation glaucoma (PXG).

METHODS

This prospective cross-sectional study included 32 PXS eyes of 24 patients and 94 PXG eyes (early-stage (n: 55) and advanced-stage glaucoma (n: 39) of 78 patients. Global and six sectors of RNFL thicknesses and BMO-MRW parameters were measured with enhanced depth imaging (EDI) mode of SD-OCT. Structural parameters; lamina cribrosa thickness (LCT), lamina cribrosa depth (LCD), prelaminar tissue thickness (PLTT), four quadrants of peripapillary choroidal thicknesses (PPCT), and subfoveal choroidal thickness (SFCT) were measured and statistical relationships between the structural parameters have been laid out. We apply the generalized estimating equations method to take into account dependency of right and left eyes.

RESULTS

From PXS to mild and advanced PXG groups LCT and PLTT decrease from 147.29 ± 33.10, 145.62 ± 30.64, 126.30 ± 29.14 and 260.93 ± 185.07, 247.27 ± 142.58, 159.89 ± 86.84, respectively, and LCD varies as 159.89 ± 86.84, 420.88 ± 117.80, and 505.64 ± 183.25. The correlations between LCD, LCT, and PLTT and the stage of the disease are significant. BMO-MRW shows slightly stronger correlations than the RNFL with LC related parameters. SFCT does not exhibit any significant relationship with the stage of the disease. However, PPCT in only the interior quadrant does. The significant correlations between LCD and all quadrants of PPCT is the sign of important anatomic relationship.

CONCLUSION

These findings show that the BMO-MRW parameter may be more sensitive than RNFL and can safely be used in the diagnosis and follow-up in PXS and PXG, but this result should be supported with longer and larger series.

Choroidal Thickness Profile in Chorioretinal Diseases: Beyond the Macula

Enhanced depth imaging optical coherence tomography (EDI-OCT) and swept-source OCT (SS-OCT) have emerged as essential diagnostic tools in the study and management of various chorioretinal diseases. Evidence from early clinical studies using EDI-OCT and SS-OCT indicates that choroidal dysfunction plays a major role in the pathogenesis of chorioretinal diseases. Measurement of choroidal thickness (CT) has already become a major research and clinical method, and CT is considered as an indicator of choroidal status in a variety of ophthalmic diseases. Recently, CT measurement has also been proposed as a non-invasive marker for the early detection and monitoring of various systemic diseases. Among the several possible CT measurement locations, subfoveal CT has rapidly become a reliable parameter for measuring CT in healthy and diseased eyes. Moreover, recent advancements in OCT technology have enabled faster and wider imaging of the posterior part of the eye, allowing the various changes in CT as measured outside the macula to be shown accordingly. In this review, we first provide an overview of the results of clinical studies that have analyzed the healthy macular choroid and that in various chorioretinal diseases, and then summarize the current understanding of the choroid outside the macula. We also examine the CT profile as an index that encompasses both within and outside of the macula. Furthermore, we describe the clinical applications of ultrawide OCT, which enables visualization of the far periphery, and discuss the prospects for the development of more reliable choroidal parameters that can better reflect the choroid's characteristics.

Ocular blood flow and choroidal thickness in ocular hypertension

PURPOSE

Ocular hypertension (OHT) is a clinical entity characterized by elevated intraocular pressure (IOP) without optic nerve damage. In the presence of other risk factors, OHT may progress to glaucoma. This study aimed to evaluate ocular blood flow (OBF) and choroidal thickness (CT), which may be markers and/or risk factors that could assess the progression of OHT to glaucoma.

MATERIAL AND METHODS

Age and gender matched 60 eyes of 32 patients with OHT and 61 eyes of 31 control patients were included for this study. All participants underwent a detailed ophthalmological examination including best-corrected visual acuity, IOP measurement with Goldmann applanation tonometry, gonioscopy, optic nerve evaluation with 78 D lens, and visual field test with Humphrey visual field analyzer. Retinal nerve fiber layer, ganglion cell complex, and central corneal thickness measurements were performed by optical coherence tomography (OCT). CT was measured with OCT in the fovea, 1.5 mm, 2 mm, 2.5 mm nasal and temporal to the fovea and from nasal and temporal to the optic disk. OBF data including peak systolic velocity (PSV), end-diastolic velocity (EDV), resistivity index (RI) and pulsatility index (PI) were measured with color Doppler imaging (CDI) from the ophthalmic artery (OA), central retinal artery (CRA), medial and lateral branches of short posterior ciliary arteries (MPCA, LPCA). Systolic (SBP) and diastolic arterial blood pressure were also noted.

RESULTS

CT measurement at each point in the OHT group compared to the control group were found to be significantly thinner (p = 0.001). There was a decrement in CT from the fovea to the nasal and temporal retina in both groups. In the OHT group, there was a significant decrease in PSV and EDV of OA, CRA, MPCA, and LPCA, and a significant increase in PI and RI of measured arteries. (EDV p = 0.036, PI p = 0.006, RI p = 0.006 for OA and p = 0.001 for other arteries and all OBF measurements). There was a negative correlation between CT and age, IOP and axial length (AL) in OHT group (r = - 0.529, p = 0.001; r = - 0.258, p = 0.047; r = - 0.345, p = 0.007, respectively, for fovea). But there was no statistically significant correlation between CT and other measurements in the control group, except age (r = - 0.860 p = 0.001 for fovea).

CONCLUSION

We found that OBF decrement and choroidal thinning in OHT group compared with controls. Interpretation both of CT measurements with OCT and OBF parameters with CDI and new imaging technologies may help to prevent and reduce the possible optic nerve damage.

Macular choroidal thickness: evaluation of variability among measurements and assessment of predictive value of glaucomatous visual field damage

INTRODUCTION

To investigate the relationship between the choroidal circulation and glaucoma, assessing macular choroidal thickness (MCT) as a predictive value of glaucomatous visual field damage.

METHODS

Twenty primary open-angle glaucoma patients were recruited. Patients underwent two SS-OCTs scans: one with DRI OCT (Topcon) and the other with PLEX Elite 9000 (Zeiss). Standard OCT parameters were acquired by DRI OCT, while MCT was manually measured in 5 points on Plex ELITE 9000 images. The relationship among MCT, standard OCT parameters and visual field indices were evaluated. Pearson's r correlation was calculated to evaluate these relationships. Reproducibility of measurements was analyzed.

RESULTS

MCT measurements showed a good intra- and inter-observer repeatability. A negative correlation appeared between MCT and body mass index (BMI) (r = -0.518, p=0.023). Mean deviation showed a statistically significant correlation with MCT measured at sub-foveal and at 1000 µm nasally (r = 0.50, p=0.03 and r = 0.52, p=0.023). A correlation was found between the two MCT (Zeiss vs Topcon) measurements and between MCT and peripapillary choroidal thickness (r = 0.944 and r = 0.740, p<0.001, respectively).

CONCLUSIONS

A good intra- and inter-observer reproducibility was found. MCT showed a weak predictive value of glaucomatous visual field damage. A significant correlation was found between MCT and BMI.

Comparison of Choroidal Vascularity Index in Patients with Pseudoexfoliation Glaucoma, Pseudoexfoliation Syndrome, and Healthy Controls

PURPOSE

To compare peripapillary choroidal vascularity index (CVI) parameters in pseudoexfoliation glaucoma (PEG), pseudoexfoliation (PEX) syndrome, and healthy controls.

METHODS

A total of 240 eyes of 240 patients were included in this cross-sectional prospective study, and the three groups consisted of (i) 80 eyes of 80 patients with PEG, (ii) 80 eyes of 80 patients with PEX syndrome, and (iii) 80 healthy control eyes. Peripapillary enhanced depth imaging optical coherence tomography images were binarized via standard protocols with the ImageJ software. CVI was analyzed in all sectors of the peripapillary region.

RESULTS

Peripapillary CVI was found to be significantly lower in the PEG group (61.6 ± 2.32) compared with the PEX group (64.7 ± 3.15) and the control group (67.5 ± 2.44) (p < .001), and patients with PEX also had significantly lower values compared to controls (p < .001). Peripapillary CVI values were significantly lower in the temporal, nasal, superotemporal, superonasal, inferotemporal and inferonasal sectors of the PEG group compared to both the PEX group and controls (p < .001). Peripapillary CVI was also found to be lower in all sectors in the PEX group compared to controls (p < .001). Global peripapillary choroidal thickness was significantly thinner in the PEG group than the PEX and control groups (133.37 ± 39.16, 154.36 ± 33.28 and 157.82 ± 36.77 μm, respectively, p < .001).

CONCLUSIONS

In the current study, it was shown that the presence of PEX caused a decrease in CVI value and this decrease was highest in patients with PEG. CVI may be a useful parameter to show vascular dysfunction in PEG and PEX syndrome.

Decreased iris thickness on swept-source optical coherence tomography in patients with primary open-angle glaucoma

PURPOSE

To investigate the iris thickness (IT) of patients with primary open-angle glaucoma (POAG) and older adults using anterior segment swept-source optical coherence tomography (SS-OCT).

METHODS

In this comparative cross-sectional study, 154 participants were enrolled, including 40 patients with POAG and 114 healthy individuals. Nasal-angle SS-OCT images were analysed using callipers to measure the thickness of the iris, including the anterior border layer, stromal, and pigmented epithelial layer, at 1 and 2 mm from the pupil edge. The relationship between IT and glaucoma severity was analysed, and receiver operating characteristic curves were constructed to assess the ability of each IT parameter to distinguish patients with glaucoma from healthy controls.

RESULTS

The IT parameters and iris area were lower in the POAG group than in the age-matched control group (p < 0.05). In the POAG group, the thickness of the pigmented epithelial layer at 1 and 2 mm was significantly correlated with the severity of glaucoma (p < 0.05). Iris area, with a cut-off of 1.43 mm² _, exhibited the highest sensitivity (85%) and specificity (64.81%; area under the curve = 0.783) for distinguishing patients with POAG from healthy controls. Older adults tended to have the thinnest IT, children had the smallest iris area (p < 0.05).

CONCLUSIONS

In patients with POAG, the severity of iris atrophy was associated with glaucoma severity. The results of IT measurements by SS-OCT may help in the clinical evaluation of POAG.

Peripapillary choroidal thickness assessed by spectral-domain optical coherence tomography in normal Japanese

PURPOSE

To investigate peripapillary choroidal thickness (PPCT) in normal Japanese subjects by using spectral-domain optical coherence tomography (SD-OCT) with enhanced depth imaging (EDI) technique and evaluate its association with ocular and systemic factors.

STUDY DESIGN

Cross-sectional study.

METHODS

This study included 85 eyes of 85 normal Japanese subjects. Normal subjects were defined as those without retinal and optic nerve disorders of any kind. The PPCT was measured at the location of 3.4 mm diameter peripapillary circle centered on the optic nerve head. It was measured as the distance between the retinal pigment epithelium and scleral-choroidal interface at the following six sectors; temporal, supra-temporal, supra-nasal, nasal, infero-nasal, and infero-temporal. Global PPCT was calculated based on these sectorial data. In addition, association between the PPCT and ocular and systemic factors were evaluated.

RESULTS

Among the included subjects, 39 (45.9%) were men and mean age was 51.4 ± 17.6 years. The mean global PPCT was 135.8 ± 40.6 µm. The infero-nasal and infero-temporal sectors were significantly thinner than other sectors (all, P < 0.05). In multiple regression analysis, thinner global PPCT was significantly associated with older age (P < 0.0001) and female sex (P = 0.0330) after considering effects of other confounders.

CONCLUSIONS

This study provided global PPCT and its profile in normal Japanese subjects by using EDI SD-OCT. These results may be used as a reference in the assessment of normal status of the PPCT. The age and sex of the subjects should be considered in interpreting the PPCT data.

Correlation Analysis between Macular Choroidal Thickness and Visual Field Mean Defect in Primary Open-Angle Glaucoma

Purpose

To evaluate the differences in macular choroidal thickness and volume between patients with primary open-angle glaucoma (POAG) and healthy controls to assess the correlation between macular choroidal thickness and visual field mean defect (MD).

Methods

Case-control study. A total of 101 patients (101 eyes) with POAG who were hospitalized in our hospital and 102 healthy subjects (102 eyes) matched by age, sex, and axial length were consecutively selected as the POAG group and the control group, respectively. The macular choroidal thickness and volume in nine regions were measured in all subjects by enhanced-depth imaging optical coherence tomography (EDI-OCT).

Results

The mean thicknesses of the choroid in the macular area in the POAG group and healthy group were 207.97 ± 62.83 µm and 208.24 ± 47.97 µm, and the mean volumes were 0.63 ± 0.19 µm³ and 0.64 ± 0.14 µm³. There were no significant differences in macular choroidal thickness, volumes of various macular regions, or mean choroidal thickness or volume between the POAG and healthy groups (all p > 0.05). The macular choroidal thickness of various macular regions was not correlated with visual field MD in the POAG group (all p > 0.05).

Conclusion

The macular choroidal thicknesses and volumes in POAG patients were not significantly different from those in healthy individuals. The macular choroidal thickness was not correlated with MD in POAG patients. Therefore, macular choroidal thickness is not an appropriate parameter to evaluate damage caused by POAG, and the role of the macular choroid thickness in POAG needs to be further investigated.

EDI-OCT choroidal thickness in Posner-Schlossman syndrome

PURPOSE

To compare the choroidal thickness (CT) of the affected eyes with the contralateral eyes in the active period and in the remission period in Posner-Schlossman syndrome (PSS) using EDI-OCT.

PATIENTS AND METHODS

This prospective longitudinal study included 15 patients with PSS and 15 age- and sex-matched healthy subjects. All subjects underwent complete ophthalmologic examinations, and EDI-OCT was conducted to measure macular CT (mCT) at the subfoveal locations and at 0.5, 1.0 and 2.0 mm superior, inferior, nasal and temporal to the fovea. The mean measurements at each location were used for analysis. Linear regression analysis was performed to analyse the correlation between the choroidal thickness and IOP, and the correlation between the choroidal thickness and episode time.

RESULTS

The mean mCT was significantly thinner in affected eyes than in contralateral eyes in the acute phase (p = 0.010) but were not different in the remission phase (p = 0.404). The mean mCT was significantly increased in the remission phase compared to that in the acute phase in the affected eyes (p = 0.000). The mCT of healthy subjects was significantly thicker than in the affected eyes (p = 0.020) and similar to the fellow eyes of PSS patients (p = 0.357) in the acute phase. Linear regression analyses show negative correlations between the mCT changes and IOP changes in the affected eyes compared to those in the fellow eyes in the acute period (R² = 0.396, p = 0.033) and between the mCT changes and IOP changes from the acute period to the remission period in the affected eyes (R² = 0.372, p = 0.027). Linear regression analyses show positive correlations (age- and sex-matched) between the CT changes and episode time from the affected eyes to the fellow eyes in the acute period (R² = 0.492, p = 0.012).

CONCLUSIONS

The mCT values of the PSS-affected eyes were significantly thinner than those of the fellow eyes in the acute phase and in the remission phase, and this change was correlated with IOP reduction and episode time.

Comparison of peripapillary and subfoveal choroidal thickness in normal versus primary open-angle glaucoma (POAG) subjects using spectral domain optical coherence tomography (SD-OCT) and swept source optical coherence tomography (SS-OCT)

Objective

To elucidate the difference between choroidal thickness (CT) in primary open-angle glaucoma (POAG) and normal subjects and to compare the CT measured using spectral domain optical coherence tomography (SD-OCT) and swept source optical coherence tomography (SS-OCT).

Methods and analysis

This cross-sectional observational study included 25 eyes of 17 POAG subjects (cases) and 31 eyes of 20 normal subjects (controls). All the patients underwent complete ophthalmologic examination, enhanced depth imaging, SD-OCT and SS-OCT. In both controls and cases, the CT was measured in seven predetermined points in macular and peripapillary area and were compared.

Results

Choroid was significantly thicker on SS-OCT compared with SD-OCT in peripapillary and macular area in both cases and controls, except for inferior peripapillary in controls. The CT was not different from glaucoma and controls in peripapillary or macular area on SD-OCT (p>0.05), however, the CT was significantly thicker in glaucoma compared with controls in peripapillary area on SS-OCT (p<0.05) except inferior peripapillary (p=0.13). There was good intraobserver (±20 µm) and interobserver (±55 µm and ±45 µm) agreement on both SD-OCT and SS-OCT respectively.

On SD-OCT, choroid was thinnest at the temporal peripapillary and thickest at subfoveal location in controls. In POAG, choroid was thinnest at inferior peripapillary region and thickest (500 µm) nasal to the fovea. On SS-OCT, choroid was thinnest at inferior peripapillary and thickest at the temporal peripapillary area in both cases and controls.

Conclusion

CT measurements on SS-OCT were higher than the SD-OCT measurements possibly due to better delineation of the sclerochoroidal junction on SS-OCT. CT was significantly thicker in glaucoma subjects compared with controls in peripapillary area on SS-OCT but not in macular area.

Lamina Cribrosa and Choroid Features and Their Relationship to Stage of Pseudoexfoliation Glaucoma

Purpose

To better understand the relationship of lamina cribrosa (LC) and choroid features to the severity of pseudoexfoliation glaucoma (PXG).

Methods

In this cross-sectional study, 137 eyes of 122 subjects (47 eyes with moderate/advanced PXG [mean deviation (MD), -15.0 ± 7.7 dB], 34 eyes with mild PXG [MD, -2.7 ± 1.5 dB], 32 aged-matched pseudoexfoliation syndrome [PXS] eyes, and 24 aged-matched control eyes) were investigated. Optic discs, LC thickness, and anterior LC depth (ALD; midsuperior, center, and midinferior) as well as peripapillary choroidal thickness were determined. Linear mixed modeling was used to adjust for age, sex, and axial length.

Results

A progressive decrease in LC thickness was found when comparing controls (271.9 ± 61.3 μm), PXS (212.6 ± 51.5 μm), mild PXG (180.8 ± 24.6 μm), and moderate/advance PXG (138.9 ± 37.5 μm) (P < 0.001). ALD was greater (P < 0.001) in moderate/advance glaucoma (306.7 ± 105.3 μm) and mild PXG (209.5 ± 79.7 μm) compared with PXS (155 ± 86.7 μm) and healthy controls (149.2 ± 103 μm). Although eyes with moderate/advance PXG had the thinnest choroid (117.2 ± 36.6 μm), choroidal thickness was comparable in mild PXG, PXS, and controls (150.0 ± 46.1, 159.7 ± 65.5, and 157.5 ± 51.1 μm, respectively; P = 0.002). Worse MD was the only factor associated with thinner LC (β = 2.344, P < 0.001) and choroid (β = 1.717, P = 0.009 μm) in PXG eyes. Higher IOP (β = 4.305, P = 0.013) and worse MD (β = -6.390, P < 0.001) were associated with deeper ALD in PXG.

Conclusions

In pseudoexfoliation, LC thinning is an early sign, and there is progressive thinning with advancing glaucoma. Choroidal thinning is observable only with moderate/advanced glaucoma. In PXG eyes, LC thickness, depth, and peripapillary choroidal thickness are associated with glaucoma severity.

Comparison of peripapillary and macular choroidal thickness and ganglion cell complex thickness in glaucomatous and healthy eyes

AIM

To assess choroidal thickness (CT) and its association with ganglion cell-inner plexiform layer thickness (GCIPLT) and retinal nerve fiber layer thickness (RNFLT) in open angle glaucoma (OAG) comparing with preperimetric glaucoma (PPG) and normal eyes.

METHODS

Totally 55 eyes of OAG, 40 eyes of PPG, and 40 eyes of age-matched normal eyes were studied. Peripapillary CT (PCT), macular CT (MCT), RNFLT, and GCIPLT were evaluated. Relationship between the CT with RNFLT and GCIPLT were studied. The correlation between CT and confounding variables as gender, age, intraocular pressure, and visual field mean deviation were analyzed.

RESULTS

Mean PCT were 113.6±39.1 µm in OAG, 116.3±42.7 µm in PPG, and 148.9±41.7 µm in normal eyes. PCT and MCT was thinner in OAG compared to healthy eyes. There was a significant correlation for PCT and mean RNFLT in 1, 2, 6, and 7 clock hours of OAG eyes. The difference in PCT remained after adjusting for axial length, age, and disc area (P=0.003). No significant correlation was shown between MCT and mean GCIPLT in all eyes.

CONCLUSION

PCT is thinner in OAG and PPG compared with healthy eyes. The correlation of RNFLT and PCT found in OAG and PPG is not revealed in normal eyes.

A Longitudinal Analysis of Peripapillary Choroidal Thinning in Healthy and Glaucoma Subjects

PURPOSE

To evaluate the rate of peripapillary choroidal thinning in glaucoma patients and healthy controls using spectral domain optical coherence tomography.

DESIGN

Cohort study.

METHODS

Participants from the multicenter African Descent and Glaucoma Evaluation Study and Diagnostic Innovations in Glaucoma Study were included. The San Diego Automated Segmentation Algorithm was used to automatically segment and measure peripapillary choroidal thickness (PCT) from circle scans centered on the optic nerve head. The rate of PCT thinning was calculated using mixed effects models.

RESULTS

Two hundred ninety-seven eyes with a median follow-up of 2.6 years were included. At baseline, the global mean PCT was significantly thinner in glaucoma patients than healthy control subjects (141.7 ± 66.3 μm vs 155.7 ± 64.8 μm, respectively; P < .001). However, when age was included in the model, this difference was no longer significant (P = .38). Both healthy controls and glaucoma patients had a significant decrease in mean (95% confidence interval) PCT change over time (-2.18 [-2.97 to -1.40 μm/year] and -1.88 [-3.08 to -0.67 μm/year], respectively) and mean PCT percent change over time (-3.32% [-4.36 to -2.27 μm/year] and -2.85% [-4.64 to -0.99 μm/year], respectively). No significant difference was found between healthy control subjects and glaucoma patients in the mean rate of PCT change (P = .28) or PCT percentage change over time (P = .23).

CONCLUSIONS

The rate of peripapillary choroidal thinning was not significantly different between healthy and glaucoma eyes during this relatively short follow-up period. Longer follow-up is needed to determine whether monitoring the rate of PCT change has a role in glaucoma management.

The diagnostic use of choroidal thickness analysis and its correlation with visual field indices in glaucoma using spectral domain optical coherence tomography

PURPOSE

To evaluate the quantitative characteristics of choroidal thickness in primary open-angle glaucoma (POAG), normal tension glaucoma (NTG) and in normal eyes using spectral-domain optical coherence tomography (SD-OCT). To evaluate the diagnostic ability of choroidal thickness in glaucoma and to determine the correlation between choroidal thickness and visual field parameters in glaucoma.

METHODS

A total of 116 subjects including 40 POAG, 30 NTG and 46 healthy subjects were enrolled in this study. Choroidal thickness measurements were acquired in the macular and peripapillary regions using SD-OCT. All subjects underwent white-on-white (W/W) and blue-on-yellow (B/Y) visual field tests using Humphrey Field Analyzer. The receiver operating characteristic (ROC) curve and the area under curve (AUC) were generated to assess the discriminating power of choroidal thickness for glaucoma. Pearson's correlation coefficients were calculated to assess the structure function correlation for glaucoma patients.

RESULTS

No significant differences were observed for macular choroidal thickness among the different groups (all P > 0.05). Regarding the peripapillary choroidal thickness (PPCT), significant differences were observed among the three groups (all P < 0.05). Post hoc tests for multiple comparisons revealed a significant difference in the NTG-normal comparison group (all P < 0.01). The inferior and temporal PPCT in POAG patients were significantly thinner than those in normal subjects (P = 0.007, P = 0.002, respectively). Different parameters of PPCT showed significantly low diagnostic values to detect POAG from normal subjects (AUC: 0.555 to 0.652) and to discriminate NTG from POAG (AUC: 0.462 to 0.702), but moderate diagnostic power to detect NTG from normal subjects (AUC: 0.708 to 0.771). Regarding the diagnosis of early glaucoma, different parameters of PPCT showed relatively low diagnostic power (AUC: 0.606 to 0.698). In all the glaucoma subjects, PPCT was not significantly correlated with W/W mean deviation (MD) (all P > 0.05), but showed significant correlations with B/Y MD (all P < 0.05). In the early glaucomatous eyes, PPCT showed significant correlations with W/W MD and B/Y MD (all P < 0.05).

CONCLUSIONS

In our study, peripapillary choroidal thickness measured on OCT showed a low to moderate but statistically significant diagnostic power and a significant correlation with blue-on-yellow visual field indices in glaucoma. This may indicate a potential adjunct for peripapillary choroidal thickness in glaucoma diagnosis.

SD-OCT Choroidal Thickness in Advanced Primary Open-Angle Glaucoma

PURPOSE

To assess the choroidal thickness in advanced primary open-angle glaucoma (POAG) comparing patients affected by advanced glaucoma and normal subject using spectral domain optical coherence tomography (SD-OCT).

METHODS

In total, 35 eyes of 35 patients affected by POAG with advanced perimetric defect (mean deviation worse than -12 dB) were prospectively enrolled and underwent a complete ophthalmologic examination, including enhanced depth imaging SD-OCT. One eye of 35 healthy subjects served as control group. Choroidal thickness was measured at the subfoveal location, at 0.5, 1.0, and 2.0 mm nasal and temporal to the fovea. Primary outcome measure was the identification of different choroidal thickness between advanced glaucoma patients and normal subjects.

RESULTS

Glaucoma and control group were homogenous for age, sex, and axial length (P>0.05 in all cases). A significant difference was found in the subfoveal choroidal thickness (SFCT) adjusted for age and axial length between glaucoma and control eyes (P=0.042); in glaucoma patients the mean adjusted SFCT was 209.90 μm compared with 234.78 μm in control subjects. Both temporal and nasal choroidal thickness measurements followed the same SFCT trend, even if only temporal ones were statistically significant. We also found that SFCT decreased with age and increased axial length (P=0.007 and 0.001, respectively). Sex and intraocular pressure did not significantly influence the choroidal thickness (P=0.87 and 0.35, respectively).

CONCLUSIONS

Patients affected by advanced POAG damage have a thinner choroidal thickness compared with normal subjects, using SD-OCT. We also confirmed that age and axial length were the main factors affecting choroidal thickness in these patients.

Assessment of peripapillary choroidal thickness in primary open-angle glaucoma patients with choroidal vascular prominence

PURPOSE

To investigate the relationship between peripapillary choroidal thickness (PCT) and choroidal vascular prominence (CVP) colocalized with retinal nerve fiber layer (RNFL) defect in primary open-angle glaucoma (POAG) eyes and to evaluate the relationship between PCT and POAG severity.

METHODS

In this cross-sectional comparative study, 29 POAG patients with CVP on RNFL imaging (Group A), 70 POAG patients without CVP (Group B) and 63 healthy controls (Group C) were examined. Various factors including age, intraocular pressure (IOP), spherical equivalent (SE), axial length (AXL), central corneal thickness (CCT), peripapillary RNFL thickness, visual-field mean deviation (MD) and pattern standard deviation (PSD) were investigated. Also, PCT (average, clock-hour) was measured by swept-source optical coherence tomography. The differences in each of the factors were analyzed among the groups.

RESULTS

There was no significant difference in age, IOP, SE, AXL or CCT among the three groups (P > 0.05). MD, PSD and RNFL thickness (RNFLT) in Groups A and B were lower than in Group C, but there was no difference between Groups A and B. There was a significant difference in adjusted PCT between Groups A and B (79.39 ± 6.56 vs. 115.87 ± 4.25, P < 0.001). Every adjusted clock-hour PCT in Group A was significantly thinner than in Group B.

CONCLUSIONS

CVP in red-free RNFL images indicated severe thinning of PCT. Although PCT thinning was not related to glaucoma severity, CVP in red-free RNFL images should be observed as an indicator of PCT thinning, associated with POAG.

Spectral Domain-Optical Coherence Tomography As a New Diagnostic Marker for Idiopathic Normal Pressure Hydrocephalus

PURPOSE

Characterized by a progressive onset of gait disturbances, dementia, and urinary incontinence, idiopathic normal pressure hydrocephalus (iNPH) is considered a rare, but under-diagnosed disease. Non-invasive diagnostic markers are still insufficient to enable the diagnosis of iNPH with certainty and yet early treatment with ventriculoperitoneal (VP) shunting can reverse symptoms and stop disease progression. Vascular circulation abnormalities in iNPH may be reflected by changes in subfoveal and peripapillary choroidal thickness (PPChT). This study uses spectral domain-optical coherence tomography (SD-OCT)-based measures of retinal and choroidal thickness to test this hypothesis and to assess ophthalmological non-invasive markers for iNPH.

METHODS

Twelve patients who displayed neurological and neuroradiological characteristics of iNPH were subject to a full ophthalmological examination including enhanced depth imaging (EDI) SD-OCT. Of the 12 included iNPH patients, 6 had undergone VP shunting with beneficial outcome. Parameters studied with EDI SD-OCT were macular retinal thickness (MT), subfoveal choroidal thickness (SFChT), retinal nerve fiber layer thickness (RNFL), and PPChT. Results were compared with 13 healthy, age-matched controls.

RESULTS

Macular thickness and RNFL and MT values of iNPH patients did not reflect atrophy. Non-shunted iNPH patients showed significantly lowered median PPChT and SFChT values compared to healthy controls. Shunted iNPH patients displayed a significantly higher median PPChT and SFChT compared to non-shunted iNPH patients. SFChT and PPChT values in shunted patients were not significantly different to values in healthy controls.

CONCLUSION

Although limited by small sample size, SD-OCT measures in this study reveal significant changes of choroidal thickness and support the hypothesis of choroidal susceptibility to hemodynamic alterations in iNPH. Non-shunted iNPH patients in this study show choroidal thinning in combination with normal RNFL and MT values. In addition to neurological and neuroradiological exams, this pattern may aid in the challenging diagnosis of iNPH.

Choroidal area assessment in various fundus sectors of patients at different stages of primary open-angle glaucoma by using enhanced depth imaging optical coherence tomography

To compare the choroidal area in different eye fundus sectors of subjects with normal eyes, early-stage primary open-angle glaucoma (POAG) eyes, and 10° tubular visual field POAG eyes using enhanced depth imaging optical coherence tomography.Twenty-five normal, 25 early-stage POAG, and 25 ten-degree tubular visual field POAG eyes were recruited. Enhanced depth imaging optical coherence tomography was used to measure the choroidal area in different fundus sectors (fovea; 10° superior, inferior, temporal, and 24° superior, inferior, temporal, nasal to the fovea) and the peripapillary sector.There were neither significant differences in the choroidal area at any of the 8 measured fundus sectors, nor significant differences in the percentage change between the choroidal area of the fovea and other 7 measured fundus sectors among the 3 groups (all P > 0.05). For the total peripapillary choroidal area, no significant difference was found among the 3 groups (P > 0.05); however, the temporal peripapillary choroidal area of 10° tubular visual field POAG eyes was significantly thicker than that of normal eyes (4,46,213 ± 1,16,267 vs 3,74,164 ± 1,21,658 μm; P = 0.048).Our study showed that there was no significant difference in the choroidal area of the 8 measured fundus sectors among normal, early-stage POAG, and 10° tubular visual field POAG eyes, suggesting that there might be no blood redistribution from the peripheral choroid to the subfoveal choroid. However, the thicker temporal peripapillary choroidal area might play a role in the central visual acuity protection in patients with POAG.

Retinal and choroidal oxygen saturation of the optic nerve head in open-angle glaucoma subjects by multispectral imaging

The aim of this study was to determine whether differences exist in oxygen supply to the optic nerve head (ONH) from the retinal and choroidal vascular layers in patients with primary open angle glaucoma (POAG) using multispectral imaging (MSI).This ia an observational, cross-sectional study.Multispectral images were acquired from 38 eyes of 19 patients with POAG, and 42 healthy eyes from 21 matched volunteers with Annidis' RHA multispectral digital ophthalmoscopy. Superficial and deeper oxygen saturation of the optic disc was represented by the mean gray scale values on the retinal and choroidal oxy-deoxy maps, respectively. Statistical analysis was performed to detect differences in ONH oxygen saturation between the 2 groups. Oxygen saturation levels in the eyes of POAG patients with severe glaucoma were compared to those of fellow eyes from the same subjects. Linear correlation analysis was performed to assess the association between ONH oxygen saturation and systemic and ocular parameters.No statistical difference was found in retinal and choroidal oxygen saturation between the POAG and control groups. In the glaucoma patients, retinal oxygen saturation was lower for eyes with worse visual fields than in those with good visual fields (t = 4.009, P = 0.001). In POAG patients, retinal oxygen saturation was dependent on mean defect of visual field and retinal nerve fiber layer thickness (RNFLT) (r = 0.511, 0.504, P = 0.001, 0.001, respectively), whereas the choroid vasculature oxygen saturation was inversely related to RNFLT (r = -0.391, P = 0.015). An age-dependent increase in retinal oxygen saturation was found for both the POAG and control groups (r = 0.473, 0.410, P = 0.007, 0.003, respectively).MSI revealed a significant correlation between functional and structural impairments in glaucoma and retinal oxygen saturation. MSI could provide objective assessments of perfusion impairments of the glaucomatous ONH. This is a preliminary indication of the effectiveness of MSI for studying POAG.

Changes in the Choroidal Thickness and Axial Length Upon Mannitol Infusion in Patients With Asymmetric Intraocular Pressure

BACKGROUND/AIMS

To evaluate the changes in the choroidal thickness (CT) and axial length (AL) upon systemic mannitol infusion in glaucoma patients with asymmetric intraocular pressure (IOP).

MATERIALS AND METHODS

Forty glaucoma patients with asymmetric IOP, with the IOP of 1 eye ≥40 mm Hg and the fellow eye <25 mm Hg, were administered 150 mL of a 20% mannitol infusion to reduce the IOP. The CT and AL were measured before and an hour after the infusion. The relationship between the IOP reduction and the changes in the CT and AL were investigated.

RESULTS

The mean decrease in the IOP was -14.23 mm Hg (32.15%) and -4.13 mm Hg (21.40%) in the eyes with higher IOP and their fellow eyes, respectively. The mean changes in the subfoveal CT were 19.28 µm (9.20%; P<0.001) and 2.60 µm (1.93%; P=0.452) in the eyes with higher IOP and their fellow eyes, respectively. The mean changes in the AL were -0.10 µm (0.42%; P<0.001) and -0.33 mm (0.14%; P=0.008) in the eyes with higher IOP and their fellow eyes, respectively. Stepwise analysis revealed that the percent IOP change is the most influential factor on the percent change of the subfoveal CT (P<0.0001; R=0.3).

CONCLUSIONS

These results suggest that large IOP changes upon mannitol infusion cause the shortening of the AL in both the eyes and the thickening of the choroid only in the eyes with a higher IOP.

Longitudinal change in choroidal thickness after trabeculectomy in primary open-angle glaucoma patients

PURPOSE

To investigate longitudinal changes in intraocular pressure (IOP), axial length (AL), and choroidal thickness (ChT) in primary open-angle glaucoma (POAG) eyes after trabeculectomy and to evaluate the parameters that might influence those changes.

METHODS

In this prospective observational study, we recruited 28 patients with POAG (28 eyes) scheduled for trabeculectomy. The average macular ChTs and foveal retinal thicknesses along 6-mm segments centered on the fovea were examined preoperatively and postoperatively (at 1, 3, and 6 months) using swept-source optical coherence tomography. The IOP, AL, and mean deviation (MD) of standard automated perimetry (SAP) were also analyzed as independent variables.

RESULTS

Results from 16 patients were included in the final analysis. A significant increase in ChT with respect to the preoperative value was observed at every postoperative stage (1 month, P < 0.001; 3 months, P < 0.001; 6 months, P = 0.011), whereas the retinal thickness showed no significant change over the study period. The ChT increase and IOP reduction were sustained throughout the 6-month period without further significant changes. Stepwise multivariate analyses showed significant correlations between the percentage decrease in IOP and the percentage increase in ChT at 1 and 6 months postoperatively. The percentage increase in ChT was also significantly correlated with a better MD of the SAP at 1 month (β = 0.01; P = 0.009).

CONCLUSIONS

The ChT increase following trabeculectomy was sustained at 1, 3, and 6 months postoperatively. The percentage increase in ChT was significantly correlated with the percentage change in IOP and (more weakly) with better SAP MD values.

Changes in choroidal thickness after intraocular pressure reduction following trabeculectomy

PURPOSE

To evaluate the changes of peripapillary and subfoveal choroidal thickness (CT) after trabeculectomy.

METHODS

Prospective longitudinal study included 37 eyes with open-angle glaucoma. The subfoveal and peripapillary CT was measured using enhanced depth imaging spectral domain optical coherence tomography before trabeculectomy and 1 week, 3 and 6 months postoperatively. The associations between changes in the CT, intraocular pressure (IOP) and axial length were analysed.

RESULTS

The medium subfoveal CT (IQR) increased from 182 (97) μm at baseline to 267 (107) μm 1 week, 213 (97) μm 3 months and 207 (91) μm 6 months postoperatively (p < 0.001). The peripapillary CT increased in all four quadrants at all follow-ups (p < 0.05). The subfoveal and peripapillary choroidal thickening correlated with the magnitude of IOP reduction (p < 0.05) and axial length shortening (p < 0.01) during whole follow-up period. There was a peripapillary CT increase of 2.9 μm per mmHg of IOP reduction (p < 0.001, CI 1.5-4.4) and 4.8 μm per mm of baseline axial length (p = 0.049, CI 0.03-9.6) 1 week postoperatively after adjustment for baseline IOP. Six months postoperatively, the decrease in axial length was the only factor associated with peripapillary choroidal thickening (p = 0.031; regression coefficient: 73.29 μm/mm, CI 7.1-139.5).

CONCLUSION

Intraocular pressure (IOP) reduction after trabeculectomy caused the increase in subfoveal and peripapillary CT for at least 6 months postoperatively correlating with greater IOP reduction and axial length shortening. In the long term, the decrease in axial eye length, but not IOP, was the only factor to be associated with peripapillary choroidal thickening.

Assessment of Open-Angle Glaucoma Peripapillary and Macular Choroidal Thickness Using Swept-Source Optical Coherence Tomography (SS-OCT)

OBJECTIVE

To compare peripapillary and macular choroidal thickness (PCT and MCT) between open-angle glaucoma (OAG) and normal controls using swept-source optical coherence tomography (SS-OCT), and to evaluate global and localized relationships between choroidal thickness and various factors in OAG, also using SS-OCT.

METHODS

In this cross-sectional comparative study, 134 OAG patients and 73 normal controls were examined. PCT (global, 12 clock-hour sectors), MCT (global, six sectors) were measured by SS-OCT. The difference in choroidal thickness between the OAG patients and the normal controls was analyzed. The relationships between choroidal thickness and various factors including age, sex, spherical equivalent (SE), axial length (AXL), central corneal thickness (CCT), intraocular pressure (IOP), peripapillary retinal nerve fiber layer thickness (pRNFLT), visual field mean deviation (MD), ganglion cell-inner plexiform layer thickness (GCIPLT), and disc area were analyzed by univariate and multivariate linear regression. Global and regional analyses were performed in 12 segments of the peripapillary circle and in six sectors of the macula.

RESULTS

There were significant differences in global PCT and MCT between the OAG patients and the normal controls (115.22±41.17 vs. 138.89±44.70, P<0.001), (184.36±57.15 vs. 209.25±61.11, P = 0.004). The difference in global PCT remained, both after adjusting for age, AXL (117.08±3.45 vs. 135.47±4.70, P = 0.002) and also after adjusting for age, AXL, disc area (117.46±3.46 vs. 135.67±4.67, P = 0.002). But the difference in global MCT did not remain after adjusting for age, AXL, SE (188.18±4.46 vs. 202.25±6.08, P = 0.066). PCT showed significant differences between the groups in all of the 12 clock-hour sectors. These differences remained after adjusting for age, AXL and for age, AXL, disc area, with the exception of the 10 o'clock (o/c) sector. MCT in six sectors showed differences between the two groups, but they did not remain after adjusting for age, AXL, SE. In a multivariate regression analysis of the OAG patients, global PCT showed correlations with age (β = -1.18, P = 0.001), AXL (β = -14.01, P<0.001), and disc area (β = -16.67, P = 0.026). Global MCT, meanwhile, showed a significant correlation with age (β = -1.92, P<0.001), AXL. (β = -21.97, P<0.001). Choroidal thickness did not show any global or localized relationship with glaucoma severity in the OAG patients.

CONCLUSIONS

The global and all 12 clock-hour PCT, with the exception of the 10 o/c sector, were thinner in OAG; however, they did not show any correlation with glaucoma severity. Possible roles of PCT in glaucoma pathogenesis should be investigated further.

Peripapillary Choroidal Thickness and Open-Angle Glaucoma: A Meta-Analysis

Purpose. To investigate the potential relationship between open-angle glaucoma (OAG) and peripapillary choroidal thickness (PPCT). Materials and Methods. Relevant publications were searched systematically through various databases from inception to January 2016. Studies comparing PPCT in OAG patients and healthy controls were retrieved. All qualified articles were analyzed using Stata 14.0 and Revman 5.3 software. Results. A total of 13 studies were identified for inclusion. There was a significant reduction of average PPCT in OAG patients compared to control participants (WMD = −24.07, 95% CI: −34.29, −13.85). Reduction of PPCT was significant in the superior (WMD = −28.87, 95% CI: −44.96, −12.78) and nasal (WMD = −21.75, 95% CI: −41.52, −1.98) sectors, but there was no significant reduction of PPCT in the inferior (WMD = −9.57, 95% CI: −36.55, 17.40) and temporal (WMD = −13.85, 95% CI: −35.40, 7.70) sectors. No obvious publication bias was detected. Conclusions. This meta-analysis suggests that open-angle glaucoma patients have significantly decreased peripapillary choroidal thickness compared to healthy individuals. Peripapillary choroidal thickness measured by optical coherence tomography may be an important parameter to consider in open-angle glaucoma.