Analysis of short-term change in subfoveal choroidal thickness in eyes with age-related macular degeneration using optical coherence tomography

TOPOGRAPHIC CHANGES IN CHOROIDAL THICKNESS IN AGE-RELATED MACULAR DEGENERATION DURING THE DEVELOPMENT OF ACTIVE CHOROIDAL NEOVASCULARIZATION

PURPOSE

To evaluate topographic changes in choroidal thickness during development of choroidal neovascularization (CNV) in treatment-naive age-related macular degeneration (AMD) and to test the value of such changes as a predictive tool of CNV development.

METHODS

This retrospective cohort included 86 eyes that developed CNV from intermediate AMD, 43 eyes with intermediate AMD, and 36 eyes without AMD. Patients with intermediate AMD underwent spectral domain optical coherence tomography using enhanced depth imaging mode every 6 months until CNV was detected. Choroidal neovascularization was localized to one of the subfields of Early Treatment of Diabetic Retinopathy Study grid on fluorescein angiography. Average choroidal thickness of each subfield was calculated.

RESULTS

Choroidal thickness of the subfield where CNV developed at first clinical detection significantly increased compared with that 6 months before (P = 0.000 for central, P = 0.001 for superior parafoveal, P = 0.002 for temporal parafoveal, P = 0.002 for inferior parafoveal, and P = 0.001 for nasal parafoveal subfield). In eight patients who visited unexpectedly 3 months before CNV development in central subfield, choroidal thickness of central subfield increased significantly compared with that 6 months before CNV development (P = 0.001).

CONCLUSION

Choroidal neovascularization development accompanied choroidal thickening of the corresponding subfield. Regular measurement of choroidal thickness may assist in prediction of CNV.

Role of the Choroid in Age-related Macular Degeneration: A Current Review

Age-related macular degeneration (AMD) is a major cause of vision loss in the developed world and its pathogenesis is a topic of active research. To date, much study has been focused on the role of the retinal pigment epithelium (RPE) and Bruch's membrane (BrM) in AMD pathogenesis, but the role of the choroid has also been investigated. In this review, we focus on recent advancements in research in the role of the choroid in AMD, beginning with an exploration of the histopathologic, cellular and molecular changes that occur in the choroid in AMD and concluding by discussing new choroidal imaging techniques and patterns seen on fluorescein angiography, indocyanine green angiography, spectral-domain optical coherence tomography and optical coherence tomography angiography. Exploring these domains will lead to a better understanding of the factors at play beyond the outer retina in this important disease.

Thickness of retina and choroid in the elderly population and its association with Complement Factor H polymorphism: KLoSHA Eye study

PURPOSE

To analyze the associations of retinal and choroidal thickness on enhanced-depth imaging optical coherence tomography (EDI-OCT) with clinical, ophthalmic and genetic factors in the normal elderly population (aged 65 years or older).

METHODS

In this prospective, population-based cohort study, people aged 65 years or older were enrolled in the baseline study of the Korean Longitudinal Study on Health and Aging (KLoSHA) Eye Study. All participants underwent spectral domain-OCT scan using the EDI technique. A topographic map of the retina was obtained and subfoveal choroidal thickness (SFCT) was measured manually. Blood samples from all subjects were genotyped for major age-related macular degeneration (AMD)-associated single nucleotide polymorphisms (SNPs) the major AMD-associated SNPs; CFH Y402H rs1061170, CFH I62V rs800292, ARMS2 A69S rs10490924. A statistical analysis was conducted to compare the retinal thickness, choroidal thickness, and AMD risk genotypes.

RESULTS

Among the three hundred eighty people enrolled, the mean age was 76.6 years (range 65-99 years). Factors that showed correlation with either tomographic retinal parameters, retinal nerve fiber layer, or SFCT, were age and gender. Significant age-related decrease in thickness was observed in the RNFL, mean central thickness (MCT) and SFCT. Gender differences existed in central foveolar thickness (CFT) and MCT, where it was thicker in men. While chorioretinal parameters were not related with other genotypes, CFH rs1061170 risk genotype was significantly associated with thin SFCT. The group containing the AMD- risk allele (CT) had a 14.7% reduction in the SFCT compared to the non-risk TT group.

CONCLUSIONS

In addition to the well-known association with AMD, CFH rs1061170 is a significant genetic risk factor associated with choroidal thinning in normal eyes of the elderly population. Such findings may provide further insight into the pathogenesis of age-related macular degeneration as well as normal aging. In addition, our study provides the first normative data on retinal and choroidal thickness in population-based aged groups with a mean age over seventy-five.

Subfoveal choroidal thickness predicts macular atrophy in age-related macular degeneration: results from the TREX-AMD trial

BACKGROUND

Our purpose was to evaluate the relationship between subfoveal choroidal thickness (SCT) and development of macular atrophy (MA) in eyes with age-related macular degeneration (AMD).

METHODS

This was a prospective, multicenter study. Sixty participants (120 eyes) in the TREX-AMD trial (NCT01648292) with treatment-naïve neovascular AMD (NVAMD) in at least one eye were included. SCT was measured by certified reading center graders at baseline using spectral domain optical coherence tomography (SDOCT). The baseline SCT was correlated with the presence of MA at baseline and development of incident MA by month 18. Generalized estimating equations were used to account for information from both eyes.

RESULTS

Baseline SCT in eyes with MA was statistically significantly less than in those without MA in both the dry AMD (DAMD) (P = 0.04) and NVAMD (P = 0.01) groups. Comparison of baseline SCT between MA developers and non-MA developers revealed a statistically significant difference (P = 0.03). Receiver operating characteristic curve (ROC) analysis showed the cut-off threshold of SCT for predicting the development of MA in cases without MA at baseline was 124 μm (AUC = 0.772; Sensitivity = 0.923; Specificity = 0.5). Among eyes without MA at baseline, those with baseline SCT ≤124 μm were 4.3 times more likely to develop MA (Odds ratio: 4.3, 95% confidence interval: 1.6-12, P = 0.005) than those with baseline SCT >124 μm.

CONCLUSIONS

Eyes with AMD and MA had less SCT than those without MA. Eyes with less baseline SCT also appear to be at higher risk to develop MA within 18 months.

ASSOCIATION BETWEEN THE VITREOMACULAR INTERFACE AND OPTICAL COHERENCE TOMOGRAPHY CHARACTERISTICS IN WET AGE-RELATED MACULAR DEGENERATION

PURPOSE

To study the effect of the vitreomacular interface on various wet age-related macular degeneration (AMD) characteristics including the size and type of choroidal neovascularization (CNV), choroidal thickness, and activity of the CNV.

METHODS

This was a retrospective observational cross-sectional study. The study included 43 patients (51 eyes) with treatment-naive age-related macular degeneration. Twenty-six patients with wet AMD in one eye and dry AMD in the other eye were included in a paired-eye analysis. Patients underwent optical coherence tomography examination using Heidelberg Spectralis (spectral domain optical coherence tomography) at presentation to determine the type of CNV and the vitreomacular status. In addition, various parameters were measured including the choroidal thickness and horizontal width and vertical height measurements of the CNV.

RESULTS

There was no correlation between the height, width, activity or type of the CNV, and the presence or absence of vitreomacular adhesion. The mean choroidal thickness (using enhanced depth imaging) in cases with vitreomacular adhesion was 272.57 μm compared with 197.32 μm in cases with no vitreomacular adhesion, a statistically significant difference (P = 0.003). In the paired-eye study (21 patients), there was no significant difference between the eyes with wet AMD and dry AMD with regard to vitreomacular status or the choroidal thickness. In a subgroup analysis, patients with Type 1 CNV had a significantly higher percentage of vitreomacular adhesion compared with the other eye with dry AMD (P = 0.034).

CONCLUSION

In conclusion, the vitreomacular interface does seem to be associated with an increased choroidal thickness in cases of wet AMD. Furthermore, the association between the vitreomacular interface and wet AMD is more significant for Type 1 CNV.

Choroidal Thickness in Eyes With Central Geographic Atrophy Secondary to Stargardt Disease and Age-Related Macular Degeneration

BACKGROUND AND OBJECTIVE

Choroidal thickness (CT) measurements from eyes with similar areas of macular geographic atrophy (GA) secondary to age-related macular degeneration (AMD) and Stargardt disease (STGD) were compared to determine whether GA from different diseases had a similar or different effect on the underlying subfoveal choroid.

PATIENTS AND METHODS

Eyes with the diagnosis of central GA secondary to STGD and AMD were matched, with subfoveal CT measurements obtained from the central B-scan using an enhanced depth imaging protocol. The area of GA was measured using fundus autofluorescence (FAF) imaging. AMD eyes were divided into those with and without reticular pseudodrusen.

RESULTS

A total of 22 eyes of 22 patients were included in the STGD and AMD groups and were matched with respect to the area of GA. The mean age of the STGD patients was 48.9 years (standard deviation [SD]=17.1), and the mean age was 81.8 years (SD=6.2) for the AMD patients. Mean area measurements of GA for the STGD and AMD groups were 5.4 mm2 (SD=4.1) and 5.1 mm2 (SD=4.0), respectively (P=.83). After adjusting for age and axial length, eyes with STGD had a mean CT measurement greater than the AMD eyes (336.1 µm vs. 198.1 µm, respectively; P=.039). However, this difference was driven by AMD eyes with reticular pseudodrusen (RPD) and by a single Stargardt case with a very thick choroid. Eyes with RPD had statistically thinner subfoveal CT measurements when compared with all other groups.

CONCLUSION

A small but statistically significant increase in the CT of STGD eyes was observed when compared with normal controls and AMD eyes without RPD. However, this small increase in CT was driven by a single case with a markedly thicker choroid within the STGD group, so it is unlikely that a clinically significant difference exists. However, AMD eyes with GA and RPD had significantly thinner subfoveal CT measurements.

Assessment of Choroidal Microstructure and Subfoveal Thickness Change in Eyes With Different Stages of Age-Related Macular Degeneration

Age-related macular degeneration (AMD) is a major cause of irreversible blindness. Choroidal structural changes seem to be inevitable in AMD pathogenesis. Our study revealed associated choroidal microstructural changes in AMD eyes.The aim of the study was to compare choroidal microstructural changes in eyes with AMD of different stages.The study was a retrospective, cross-sectional case series.The participants comprised of 32 age-matched normal eyes as controls, and 26 fellow uninvolved eyes of intermediate/late AMD, 29 of early AMD, 28 of intermediate AMD, and 39 of late AMD.All subjects underwent comprehensive ophthalmologic examination. The choroid images, including subfoveal choroidal thickness, percentage of Sattler layer area, and en face images of the choroid, were obtained using spectral-domain optical coherence tomography.The main outcome measures were subfoveal choroidal thickness changes, percentage of Sattler layer area changes, and en face images of the choroid in AMD eyes.One hundred fifty-four eyes of 96 individuals with mean age of 67.1±9.2 years were included. The mean subfoveal choroidal thickness was 295.4 ± 56.8 μm in age-matched normal eyes, 306.7 ± 68.4 μm in fellow uninvolved eyes with AMD, 293.8 ± 80.4 μm in early AMD, 215.6 ± 80.4 μm in intermediate AMD, and 200.4 ± 66.6 μm in late AMD (F = 14.2, all P < 0.001). Choroidal thickness was greater in early AMD eyes than in intermediate/late AMD eyes (P < 0.001). Mean percentage of Sattler layer area in each group showed a similar tendency. Microstructure of the choroid showed reduced vascular density of Sattler layer areas in late AMD eyes compared with normal eyes.Decreasing subfoveal choroidal thickness and percentage of Sattler layer area were demonstrated in the progression of AMD. The choroidal change was related to atrophy of the microstructural changes of underlying capillaries and medium-sized vessels.

Ultra-Short-Term Reproducibility of Speckle-Noise Freed Fluid and Tissue Compartmentalization of the Choroid Analyzed by Standard OCT

PURPOSE

We measured reproducibility of speckle-noise freed fluid and tissue compartmentalization of the choroid (choroidal angiography and tissue characterization).

METHODS

This study included 26 eyes of 13 healthy females: 13 were used for repeated measurements and 13 were used for side comparison. A semiautomated algorithm removed speckle-noise with structure preservation.

RESULTS

Intraclass correlation (ICC), with respect to reproducibility of the method, showed an ICC for choroidal fluid inner space analysis (FISA) of 95.15% (90.01-98.24). The ICC of tissue inner space analysis (TISA) was 99.75% (99.47-99.91). The total choroid ratio (TCR), calculated from volumes of tissue to vessels, showed an ICC of 88.84% (78.28-95.82). Comparison of eyes (left to right) showed a difference for FISA of 0.033 (95% confidence interval [CI] -0.0018-0.0680, P = 0.063), TISA -0.118 (CI -0.2373-0.0023, P = 0.055), and TCR -0.590 (CI -0.9047 to -0.2754, P = 0.004). The ICC for FISA and TISA showed a trend in the difference comparing left and right eyes; however, TCR showed a significant difference between the eyes in the measured area (P < 0.001). Mean overall FISA was 0.58 mm³ (range, 0.25-0.98 mm³, SD = 0.14). Mean TISA was 3.45 mm³ (range, 2.38-5.0 mm³, SD 0.072). Mean TCR was 6.13 (overall range, 3.93-10.2, SD = 1.34).

CONCLUSIONS

Differences in choroidal layers between subjects were found mainly due to alterations in choroidal tissue. Reproducibility of speckle-noise freed choroidal angiography appeared excellent.

TRANSLATIONAL RELEVANCE

Speckle noise is a granular "noise" that appears in a wide range of medical imaging methods as ultrasonography, magnetic resonance, computer tomography, or optical coherence tomography (OCT). Findings from basic science about speckle noise were translated into a novel, medical image postprocessing application that can separate signal from speckle noise with structure preservation with high reproducibility and enhance medical imaging.

Investigating the choriocapillaris and choroidal vasculature with new optical coherence tomography technologies

The body of knowledge of in vivo investigation of the choroid has been markedly enhanced by recent technological advances in optical coherence tomography (OCT). New insights elucidating the morphological features of the choriocapillaris and choroidal vasculature, in both physiological and pathological conditions, indicate that the choroid plays a pivotal role in many posterior segment diseases. In this article, a review of the histological characteristics of the choroid, which must be considered for the proper interpretation of in vivo imaging, is followed by a comprehensive discussion of fundamental principles of the current state-of-the-art in OCT, including cross-sectional OCT, en face OCT, and OCT angiography using both spectral domain OCT and swept source OCT technologies. A detailed review of the tomographic features of the choroid in the normal eye is followed by relevant findings in prevalent chorioretinal diseases, focusing on major causes of vision loss such as typical early and advanced age-related macular degeneration, polypoidal choroidal vasculopathy, central serous chorioretinopathy, pachychoroid spectrum disorders, diabetic choroidopathy, and myopia.

Thinning of the RPE and choroid associated with T lymphocyte recruitment in aged and light-challenged mice

PURPOSE

Thinning of the RPE and the underlying vascular layer, the choroid, is observed with age in many human eye disorders. The reasons for this thinning are ill-defined. Here, we highlight the possible role of T lymphocyte recruitment in choroidoretinal thinning in aged and light-challenged mice.

METHODS

In age and light challenge models, we measured chemokine concentrations using enzyme-linked immunosorbent assay and used flow cytometry to characterize lymphocyte populations. We quantified thinning in eye immunosections and RPE65 expression using quantitative PCR.

RESULTS

Age and light challenge led to increased levels of the lymphotactic protein CXCL10 alone (aging) or in conjunction with CXCL9 (light challenge). Increased numbers of CD3+ T lymphocytes, most of them CD8+ cytotoxic T lymphocytes, were also observed in the choroid and retina of old mice and following light challenge. Influx of T lymphocytes was associated with RPE and choroidal thinning and diminished expression of RPE65 mRNA, an essential enzyme of the visual cycle.

CONCLUSIONS

The observations from this study suggest that cytotoxic CD8(+) T lymphocytes might participate in choroidal and RPE degeneration and that modulation of T lymphocyte recruitment might be a novel strategy to reduce choroidoretinal dysfunctions observed with age and following photo-oxidative stress.

Relationship of central choroidal thickness with age-related macular degeneration status

PURPOSE

To compare choroidal thickness in patients with intermediate or advanced age-related macular degeneration (AMD) and control subjects using enhanced-depth imaging optical coherence tomography (EDI-OCT).

DESIGN

Retrospective cross-sectional study of 325 eyes from 164 subjects who underwent EDI-OCT for the Age-Related Eye Disease Study (AREDS) 2 Ancillary Spectral Domain OCT study.

METHODS

Choroidal thickness was measured by semi-automated segmentation of EDI-OCT images from 1.5 mm nasal to 1.5 mm temporal to the fovea. Multivariate linear regression was used to evaluate the association of subfoveal choroidal thickness or average choroidal thickness across the central 3-mm segment with systemic and ocular variables. Choroidal thickness measurements were compared between eyes with no AMD (n = 154) (ie, controls), intermediate AMD (n = 109), and advanced AMD (n = 62).

RESULTS

Both subfoveal and average choroidal thicknesses were associated with age (P < .001) and refractive error (P < .001), but not other variables tested. Mean average choroidal thickness was significantly reduced in advanced AMD as compared with control eyes (P = .008), with no significant difference between advanced and intermediate AMD eyes (P = .152) or between intermediate AMD and control eyes (P = .098). Choroidal thinning was also noted from 1.5 mm nasal to 1.5 mm temporal to the fovea when comparing advanced AMD with control eyes (P < .05 at all 0.5 mm interval locations). After adjustment for age and refractive error, however, there was no significant difference in subfoveal (P = .675) or average choroidal thickness (P = .746) across all 3 groups.

CONCLUSIONS

When adjusted for age and refractive error, central choroidal thickness may not be significantly influenced by AMD status based on AREDS categorization.

The Effect of Systemic Tamsulosin Hydrochloride on Choroidal Thickness Measured by Enhanced Depth Imaging Spectral Domain Optical Coherence Tomography

BACKGROUND

To evaluate the effects of selective α1A-adrenoceptor antagonist tamsulosin hydrochloride on choroidal thickness using enhanced depth imaging spectral-domain optical coherence tomography (EDI-OCT).

METHODS

This is a prospective observational study including 29 eyes of 29 patients with newly diagnosed benign prostatic hyperplasia. Choroidal thickness and retrobulbar ocular blood flow measurements were performed at baseline and after 3 months of treatment. Results were analyzed by the masked observer.

RESULTS

The mean subfoveal choroidal thickness (275.8-291.9 µm) and thicknesses 750 µm nasal (257.9-270.4 µm) and 750 µm temporal (262.4-277.0 µm) to the fovea were significantly increased after 3 months of treatment (p < 0.001). No statistically significant change was found in retrobulbar ocular blood flow.

CONCLUSIONS

Tamsulosin causes a significant increase in EDI-OCT-based choroidal thickness measurements. This increase might be associated with choroidal vasodilation in consequence of blockade of sympathetic α1A-adrenoceptors, which is critical for the maintenance of vascular tone and resistance in the choroidal vascular architecture. This should be kept in mind when choroidal disease and its response to treatment are followed by EDI-OCT imaging.

Ultrahigh-speed swept-source OCT angiography in exudative AMD

BACKGROUND AND OBJECTIVE

To investigate the potential of ultrahigh-speed swept-source optical coherence tomography angiography (OCTA) to visualize retinal and choroidal vascular changes in patients with exudative age-related macular degeneration (AMD).

PATIENTS AND METHODS

Observational, prospective cross-sectional study. An ultrahigh-speed swept-source prototype was used to perform OCTA of the retinal and choriocapillaris microvasculature in 63 eyes of 32 healthy controls and 19 eyes of 15 patients with exudative AMD.

MAIN OUTCOME MEASURE

qualitative comparison of the retinal and choriocapillaris microvasculature in the two groups.

RESULTS

Choroidal neovascularization (CNV) was clearly visualized in 16 of the 19 eyes with exudative AMD, located above regions of severe choriocapillaris alteration. In 14 of these eyes, the CNV lesions were surrounded by regions of choriocapillaris alteration.

CONCLUSION

OCTA may offer noninvasive monitoring of the retinal and choriocapillaris microvasculature in patients with CNV, which may assist in diagnosis and monitoring.