Choroidal thickness of children's eyes with anisometropic and strabismic amblyopia

Assessing Choroidal Thickness in Pediatric Patients With Unilateral Strabismic Amblyopia by Using Spectral Domain-Enhanced Depth Imaging-Optical Coherence Tomography

Objective In this study, we aimed to evaluate the choroidal thickness in patients with unilateral strabismic amblyopia by using spectral domain-enhanced depth imaging-optical coherence tomography (SD-EDI-OCT) (Heidelberg Engineering GmbH, Heidelberg, Germany). Methods Twenty-five children with strabismic amblyopia and 20 age- and sex-matched healthy controls were included in this study. Seven sections were obtained, each comprising 25 repetitive images from each section at 200-micron intervals, and measurements were taken from nine different points at vertical and horizontal lines (1 and 3 mm from the subfoveal, superior, inferior, temporal, and nasal regions), centered on the fovea, using SD-EDI-OCT. Choroidal thickness values were obtained by measuring the distance between the basal border of the retinal pigment epithelium and the choroidoscleral border. The Mann-Whitney U test was used to compare choroidal thickness between the amblyopic and the control groups. Results The mean age of children with amblyopia and that of controls were 8.4 ±2.7 and 9.9 ±3.3 years, respectively (p=0.120). The mean subfoveal choroidal thickness was 372.8 ±78.9 μm in amblyopic eyes and 372.4 ±79.3 μm in the fellow eyes, both of which were thicker than the control eyes (310.9 ±76.3 μm; p<0.05 for each). Similarly, the mean values for the choroidal thickness of the amblyopic children at 1 mm nasal (320 ±86 μm), 1 mm superior (363 ±70 μm), and 3 mm superior (336 ±62 μm) were also significantly thicker than those of the corresponding control eyes (p<0.05 for each). There was a negative correlation between the subfoveal choroidal thickness and axial length (r=-0.332, p=0.005). There were no correlations between the choroidal thickness, age, and visual acuity. Conclusions The choroidal thicknesses of strabismic and fellow eyes were similar in patients with strabismic amblyopia. However, the choroidal thickness of both eyes in strabismic children was significantly thicker than those of the healthy controls. Emmetropization may be defective in both eyes of strabismic amblyopic patients.

Protective Effect of Amblyopia on Age-Related Macular Degeneration

PURPOSE

Our aim was to evaluate whether patients with age-related macular degeneration (AMD) and cooccurrent amblyopia are more likely to have diseases diagnosed on both the ipsilateral and the contralateral side in a large Austrian database.

DESIGN

Retrospective cross-sectional study.

METHODS

Setting: Institutional practice.

PATIENT POPULATION

Medical records of all patients who visited the Department of Ophthalmology of the Medical University of Graz between December 1996 and June 2021 were searched for the co-occurrence of AMD and amblyopia.

MAIN OUTCOME MEASURES

Data from patients with AMD diagnosed on 1 eye side were used for further analysis. Spectral-domain optical coherence tomography images were analyzed to confirm the lateral asymmetry of AMD.

RESULTS

A total of 327,443 patients were screened for the co-occurrence of AMD and amblyopia. Of them, 8742 patients had AMD diagnosed on 1 eye side and 5051 patients had unilateral amblyopia. In total, 163 patients were found to have AMD diagnosed on 1 side and unilateral amblyopia in combination. Of these, 126 patients had AMD and amblyopia on contralateral sides and 37 had AMD and amblyopia on the ipsilateral side (P < .001).

CONCLUSIONS

Less amblyopic patients had AMD diagnosed on the amblyopic eye compared with the nonamblyopic eye. In cases of lateral asymmetry, the nonamblyopic eye is more likely to have the more advanced form of AMD.

Macular superficial vascular density on optical coherence tomography angiography in children with unilateral anisometropic and bilateral hyperopic amblyopia

We analyzed whether macular superficial vascular density (SVD) and foveal vascular zone (FAZ) on optical coherence tomography angiography (OCTA) can distinguish between bilateral ametropic and anisometropic amblyopia. We included 42, 33, and 50 eyes in the bilateral ametropic amblyopia, anisometropic amblyopia, and normal control groups, respectively. Using macular swept-source optical coherence tomography angiography, we measured and analyzed the superficial FAZ areas and five sectoral macular SVDs after magnification correction. The anisometropic amblyopic eye group showed significantly increased foveal SVDs (p < 0.001) and significantly decreased superficial FAZ areas (p < 0.001), compared with the remaining groups. Additionally, the bilateral ametropic amblyopia group had significantly decreased nasal SVDs. SVDs and superficial FAZ areas differed among hyperopic amblyopia subtypes. These findings may reflect vascular distribution differences and macular changes in hyperopic amblyopia subtypes compared with normal eyes.

Choroidal Thickness in Patients with Unilateral Amblyopia and Comparison between Anisometropic and Strabismic Amblyopia: A Prospective Cross-Sectional Study

Aims and Objectives

To determine the choroidal thickness (mainly subfoveal) using spectral domain optical coherence tomography (SD-OCT) in amblyopic eyes and to compare it with the choroidal thickness (CT) of healthy fellow eyes.

Materials and Methods

In this prospective study, 140 eyes of 70 patients (aged 5-40 years) with strabismic and anisometropic amblyopia were examined using enhanced depth imaging (EDI) mode in SD-OCT. The CT was measured directly below the fovea and six other locations: 500 μ, 1000 μ, and 1500 μ from fovea in both nasal and temporal quadrants.

Results

The mean age of the patients was 22.5 ± 11.2 years. The mean Best Corrected Visual Acuity (BCVA) in the amblyopic eyes was 0.87 ± 0.47 logMAR and 0 ± 0.02 logMAR in control eyes. The average subfoveal CT was 341.73 ± 60.39 μm in the amblyopic eyes and 314.77 ± 48.12 μm in the fellow eyes. Subgroup analysis showed that the patients with anisometropic amblyopia had a significantly thicker choroid as compared to the fellow healthy eyes (P = 0.00), whereas in strabismic amblyopic eyes, this difference was not significantly significant (P = 0.064).

Conclusion

Significant choroidal thickening was observed in subjects with amblyopia, which may contribute to the amblyopia pathogenesis and this could be used as a diagnostic parameter for amblyopia. These changes were more pronounced in patients with anisometropic amblyopia than strabismic amblyopia.

Microvasculature evaluation of anisometropic amblyopia children by Angio-OCT

To compare and assess the choroidal and retinal microstructural vascularity in amblyopic eyes with the fellow eyes in anisometropic amblyopic children using angiography optical coherence tomography (Angio-OCT). Twenty-seven children (54 eyes; 5.59 ± 1.08 years old; 59.3% girls) were enrolled in this study. Choroidal thickness (CT) was measured with the use of the enhanced depth imaging mode in Angio-OCT. Parafoveal/peripapillary vascular density indices and the foveal avascular zone (FAZ) size were analyzed by MATLAB code programming on Angio-OCT images. The mean FAZ size of the amblyopic eyes were larger both in superficial and deep capillary plexus layer (SCPL/DCPL). Compared with the contralateral eyes (BCVA were normal), all the vascular density indices of SCPL and DCPL in the parafoveal and peripapillary zones were lower in the amblyopic eyes, however, the difference was insignificant (p > 0.05). No significant decrease was observed in four quadrants analyses of the amblyopic eyes (p > 0.05). Except for the measurement at 2000 µm and 1500 µm from the fovea in temple, CT in amblyopic eyes were significantly thicken than the fellow eyes (p < 0.05). Compared with the fellow eyes, the CT of certain areas were thicker in the amblyopic eyes. Though the FAZ size of the amblyopic eyes was larger in SCPL/DCPL layers, the retinal vascular density indices in SCPL/DCPL were lower in amblyopia eyes without statistical difference. Angio-OCT may be an effective way to evaluate the status of the choroidal and retinal vascular system in amblyopic children.

Features of the Choroidal Structure in Children With Anisometropic Amblyopia

PURPOSE

To examine the choroidal structure in children with anisometropic amblyopia using the binarization method.

METHODS

Thirty children with unilateral anisometropic amblyopia and 30 healthy age- and sex-matched controls were included in the study. Choroidal thickness was measured with optical coherence tomography. The choroidal layer was examined with the binarization method using ImageJ software (National Institutes of Health). The total choroidal area, stromal area, luminal area, luminal area to stromal area ratio, and choroidal vascular index were calculated. The values were compared by correlating the spherical equivalent (SE) (determined by an autorefractometer) with anterior chamber depth, axial length, central corneal thickness (measured by optical biometry), and choroidal thickness values.

RESULTS

Mean SE values were 3.75 ± 2.16 diopters (D) in the amblyopic eyes, 2.39 ± 2.09 D in the fellow eyes, and -0.27 ± 0.53 D in the control eyes. Best corrected visual acuity (BCVA) was 0.29 ± 0.11 logarithm of the minimum angle of resolution (logMAR) in the amblyopic eyes, 0.02 ± 0.04 logMAR in the fellow eyes, and 0 ± 0 logMAR in the control eyes. Choroidal thickness values were 351 ± 47 µm in the amblyopic eyes, 333 ± 55 µm in the fellow eyes, and 324 ± 51 µm in the control eyes. Luminal area to stromal area ratio values were 1.73 ± 0.13 in the amblyopic eyes, 1.76 ± 0.15 in the fellow eyes, and 2.02 ± 0.25 in the control eyes. Choroidal vascular index values were 63% ± 0.02 in the amblyopic eyes, 64% ± 0.02 in the fellow eyes, and 66% ± 0.03 in the control eyes. BCVA, SE, choroidal thickness, luminal area to stromal area ratio, and choroidal vascular index were significantly different in each group. The total choroidal area, luminal area, and stromal area were similar in all eyes. No correlation was found between choroidal vascular index and choroidal thickness, anterior chamber depth, axial length, and central corneal thickness.

CONCLUSIONS

In children with anisometropic amblyopia, the total choroidal area was relatively larger in both the amblyopic and the fellow eyes compared to the control eyes. Due to the higher stromal area and lower luminal area, both the amblyopic and the fellow eyes also had lower choroidal vascular index values than control eyes. [J Pediatr Ophthalmol Strabismus. 2022;59(5):320-325.].

Optical Coherence Tomography Angiography in Patients with Amblyopia

To determine the optical coherence tomography angiography (OCTA) parameters including foveal avascular zone (FAZ) and vessel density (VD) in the amblyopic eyes compared with the fellow sound eyes and the eyes of the non-amblyopic subjects. In this case-control study, a total of 23 eyes from unilateral amblyopic children were included as cases. The sound eye of the amblyopic children was considered as the internal control and the right eyes of the non-amblyopic children were considered as the external control. All participants underwent image recording with OCTA. In the present study, an equal number of 23 unilateral amblyopic eyes and 23 right eyes of non-amblyopic age- and sex-matched children were included as the cases and controls, respectively. The average age of participants in the case and controls were 9.86 ± 3.12 and 8.5 ± 2.35 years, respectively. Twelve patients (52.2%) in the case group and 14 subjects (60.9%) in the control group were female. Whole vascular density of the macula in superficial capillary plexuses (SCP) was significantly lower in the external controls compared with the other studied groups (P = .026). However, the VD of the deep capillary plexuses (DCP) was significantly greater in the external controls than cases and internal controls (P= .029). The average FAZ area was 0.26 ± 0.06 mm² in amblyopic eyes that was significantly higher compared with fellow eyes (0.21 ± 0.07 mm²; P= .022), but it was not different with non-amblyopic eyes (0.22 ± 0.118 mm²). Based on our findings, there were no significant difference in the cases of foveal, parafoveal, and perifoveal in both superficial and deep vascular densities among amblyopic and non-amblyopic eyes, whereas deep whole density of the amblyopic eyes showed lower percent compared to non-amblyopic ones that indicates decrease blood supply of the amblyopic eyes in this region. Additionally, FAZ was larger in amblyopic eyes than internal controls.

Evaluation of Choroidal Vascular Index in Amblyopic Patients

Objectives:

To compare subfoveal choroidal thickness (SFCT) and choroidal vascular index (CVI) in patients with hyperopic refractive and strabismic amblyopia and healthy subjects.

Materials and Methods:

The study included 17 patients with strabismic amblyopia (Group 1), 29 patients with hyperopic refractive amblyopia (Group 2), and 16 eyes of 16 healthy volunteers (Group 3). Best corrected visual acuity was noted in all patients and volunteers. In addition to detailed anterior and posterior segment examinations, macular images were obtained by enhanced-depth imaging mode of optical coherence tomography (OCT). SFCT measurements were made from these images and CVI was calculated using the Image J program.

Results:

No significant difference was found between the groups in terms of age, gender, and intraocular pressure (p=0.27, 0.64, and 0.85, respectively). Mean BCVAs in Group 1 were 0.57±0.16 (0.3-0.8) in the amblyopic eyes, 0.94±0.08 (0.8-1.0) in the fellow eyes, and in Group 2 were 0.61±0.17 (0.2-0.8) in amblyopic eyes, 0.92±0.1 (0.8-1.0) in fellow eyes. BCVA in Group 3 was 1.0±0 (1.0-1.0). Mean SFCT of the amblyopic eyes in Groups 1 and 2 was 341.50±60.4 (277-481) and 370.06±65.3 (247-462), respectively, and in the healthy eyes of Groups 1 and 2 and Group 3 was 321.92±68.26 (251-440), 330.35±74.00 (194-502), and 327.62±40.79 (238-385), respectively. SFCT was significantly greater in the amblyopic eyes of Group 2 compared to Group 3 (p=0.01). Mean CVI was 0.681±0.032 (0.642-0.736) in the amblyopic eyes and 0.685±0.054 (0.587-0.788) in the fellow eyes of Group 1 patients; 0.664±0.033 (0.592-0.719) in the amblyopic eye and 0.707±0.039 (0.625-0.779) in the fellow eye in Group 2 patients; and 0.689±0.031 (0.612-0.748) in Group 3 patients. CVI was significantly lower in the amblyopic eyes of Group 2 compared with fellow eyes (p=0.02) and Group 3 (p=0.025).

Conclusion:

Morphological changes may be seen in the choroid in amblyopic eyes. We observed that the choroidal stromal component is increased in hyperopic amblyopic patients especially.

Examination of Macular Retina and Choroidal Thickness in High Myopic Amblyopia Using Spectral-Domain Optical Coherence Tomography

Purpose

The aim of this study was to investigate changes in the retinal and choroidal thickness between high myopic amblyopia (HMA), low myopia (LM), moderate myopia (MM), high myopia (HM), and normal group (NG) using a spectral-domain optical coherence tomography (SD-OCT).

Materials and Methods

A total of 75 Chinese children (128 eyes; mean age 10.5 years) were recruited. Retinal thickness (RT) and choroidal thickness (CT) were measured at different locations including subfoveal (SF), and at 0.5 mm/1.0 mm/1.5 mm/2.0 mm/2.5 mm/3.0 mm to the fovea in superior, nasal, inferior, and temporal sectors using enhanced depth imaging (EDI) system of SD-OCT. Axial length (AL), best-corrected visual acuity (BCVA), and refraction errors were also collected.

Results

No significant differences were found in subfoveal retinal thickness (SFRT). Moreover, a significantly thinner subfoveal choroidal thickness (SFCT) was found in HMA compared to NG, LM, and MM, but not compared to HM. RT at 0.5 mm to fovea, HMA was significantly thinner compared to LM and MM in the three sectors (superior, inferior, and temporal). Nevertheless, no significant differences were found compared to NG and HM. CT at 0.5 mm to fovea, HMA was the significantly thinnest in all four sectors compared to NG, LM, and MM. RT at 1.0 mm/1.5 mm/2.0 mm/2.5 mm/3.0 mm to fovea, HMA was thinner compared to NG, LM, and MM. CT at 1.0 mm/1.5 mm/2.0 mm/2.5 mm/3.0 mm to fovea, HMA was thinner compared to NG, LM, and MM. At the superior and inferior sectors, HMA showed to be statistically thinner compared with HM. Moreover, SFCT in the HMA, HM, and NG were negatively correlated with AL.

Conclusions

Thinner retina and choroidal tissue appear to be related to HMA, and thus can be used as useful parameters for discovering the underlying mechanisms of the disease.

Assessment of choroidal vascularity and choriocapillaris blood perfusion in Chinese preschool-age anisometropic hyperopic amblyopia children

PURPOSE

To determine the macular and peripapillary area choroid microstructure parameters of hyperopic anisometropic amblyopia eyes and compare to fellow and age-matched control eyes. To assess the correlation between the axial length (AL), choroidal thickness (CT) and choroid microstructure parameters.

METHODS

This cross-sectional comparative, non-interventional study involved 52 hyperopic anisometropic amblyopia children and 48 age-matched heathy controls. 52 eyes with hyperopic anisometropic amblyopia and 48 age-matched control eyes were studied. The peripapillary and subfoveal CT were determined. The total choroidal area (TCA), luminal area (LA), and stromal area (SA) of the subfoveal and peripapillary choroid were measured. In addition, the correlation between the AL, CT and choroid microstructure parameters were calculated.

RESULTS

The peripapillary and subfoveal CT of the amblyopic eyes was significantly thicker than the fellow and control eyes (all P < 0.05). The subfoveal and peripapillary choroidal SA, LA and TCA of the amblyopic eyes were significantly increased than that of the fellow and control eyes (all P < 0.05). The choroidal vascularity index (CVI) values of the amblyopic eye were significantly different among the three groups (P < 0.05). There was a statistically significant negative correlation between AL and subfoveal CT (SFCT), LA and TCA levels (P < 0.001, P = 0.039, P = 0.027, respectively). Spherical equivalent (SE) was positive correlated with SFCT, LA and TCA levels (P = 0.456, 0.229 and 0.240, respectively; all P < 0.05). There was a statistically significant positive correlation between SFCT, SE, LA, SA, TCA and CVI levels (all P < 0.05).

CONCLUSION

The subfoveal and peripapillary CT of amblyopic children abnormally increased and correlated with shorter AL and higher SE. The choroidal structure of the amblyopic eyes was different from the fellow and control eyes, the hyperopic anisometropic amblyopic eyes had significantly thicker sub-foveal choroid, higher LA, SA, and TCA. AL and CT affect choroidal structure and vascular density. Choroidal blood flow may be increased in amblyopic eyes. The larger LA, SA, TCA, and lower CVI were characteristic of the amblyopic eye.

How do the amblyopic and fellow eyes differ in adults?

OBJECTIVE

To investigate the differences between the amblyopic eye and the fellow eye in adults with anisometropic amblyopia.

MATERIALS AND METHODS

Measurements of the central macular thickness [CMT], subfoveal choroidal thickness [SFCT], and retinal nerve fiber layer [RNFL] in patients with anisometropic amblyopia were obtained using optical coherence tomography [OCT]. Axial length [AL], anterior chamber depth [ACD], and central corneal thickness [CCT] were measured with optical biometry. All 12 parameters were compared between the amblyopic eye [Group 1] and the fellow eye [Group 2].

RESULTS

A total of 110 eyes of 55 patients [9 myopic, 46 hypermetropic] were analyzed retrospectively. The ages of the patients ranged from 17 to 55 years, with a mean of 30.8±10.7 years. 56.4% [n=31] of the patients were female, and 43.6% [n=24] were male. The mean spherical equivalent [SE] was 1.96±3.79 in Group 1 and 1.28±2.45 in Group 2. SFCT was 312.00±53.03 in Group 1 and 283.47±51.91 in Group 2. AL was 22.53±1.40 in Group 1 and 22.79±1.18 in Group 2. SE, SFCT, and AL were statistically significantly different between the two groups. There was no difference between the two groups in terms of CMT, RNFL, ACD and CCT values.

CONCLUSION

In adults with anisometric amblyopia, the SFCT of the amblyopic eye is greater than that of the fellow eye. The choroid plays an important role in the nutrition of the retinal layers, the development of ocular function and refractive error, and its development may be affected by the refractive error. Since the majority of our patients were hyperopic, the AL was found to be shorter in the amblyopic eye. CMT, RNFL, ACD and CCT values were the similar in both groups. There was no clinically significant relationship between biometric parameters and OCT parameters.

OCT-Angiography Findings in Patients with Amblyopia: Comparison between Healthy Controls, Treatment-Responsive, and Treatment-Unresponsive Amblyopic Patients

There is no consensus on whether amblyopia affects the retinal vascular plexus and morphology. Previous studies focused on the differences between amblyopic patients and normal controls without evaluating amblyopic eyes after patching. To evaluate differences in the superficial vascular density of amblyopic eyes, normal eyes, and amblyopic eyes reaching normal BCVA after patch therapy, OCTA was used. All patients underwent a comprehensive ophthalmological examination, including visual acuity, refraction, ocular motility tests, and anterior and posterior segment examination. OCTA was performed by an expert physician using the Zeiss Cirrus 5000-HD-OCT Angioplex (Carl Zeiss, Meditec, Inc., Dublin, OH, USA). OCTA scans were performed using a 3 × 3 mm² and 6 × 6 mm² fovea-centered image setting. The mean outer macular vessel density in the previously amblyopic group was 19.15 ± 0.51%. This was statistically significantly higher than in both the amblyopic group (18.70 ± 1.14%) and the normal controls (18.18 ± 1.40%) (p = 0.014). The previously amblyopic group also significantly differed from both normal controls and amblyopic eyes with regards to the inner (p = 0.011), outer (p = 0.006), and full (p = 0.003) macular perfusion. Finally, linear regression analysis revealed that BCVA was linearly correlated to outer perfusion in amblyopic (p = 0.003) and ex amblyopic eyes (p < 0.001). Considering the cross-sectional nature of our study, from our results, we can only hypothesize a possible correlation between light stimulation and retinal vasculature development. However, further longitudinal studies are needed to support this hypothesis.

Choroidal, macular and ganglion cell layer thickness assessment in Caucasian children measured with spectral domain optical coherence tomography

PURPOSE

To study the subfoveal choroidal thickness (SFCT), macular ganglion cell layer (GCL-IPL) and central macular thickness (CMT) in Caucasian children, and to analyze these optical coherence tomography (OCT) parameters depending on the spherical equivalent (SE).

METHODS

Cross-sectional study of SFCT, GCL-IPL, and CMT in Caucasian children, analyzed with spectral-domain OCT Cirrus 5000 and Enhanced-depth imaging technique. Correlation between these three OCT parameters, age, sex, and spherical equivalent was analyzed. The eyes were classified into three groups: group 1 included eyes with SE < 0, group 2 included eyes with SE between 0 and +2.00, and group 3 eyes with SE > +2.00.

RESULTS

Hundred ninety-eight eyes of 121 subjects were studied. The mean age was 9.22 years (range 3-16); 61.1% were female. The mean SFCT was 351.04 ± 84.08 µm, being 310.04 ± 82.84µm in group 1 (n = 62), 373.14 ± 83.16 µm in group 2 (n = 71) and 365.18 ± 73.16 µm in group 3 (n = 65); statistically significant differences were found between groups 2 and 3, compared with group 1. GCL-IPL thickness was significantly thinner (p < 0.001) in group 1, compared with group 3. There were no statistically significant differences between the three groups regarding CMT. Correlation with age, and sex was not found.

CONCLUSIONS

SFCT and GCL-IPL thickness were significantly thinner (p < 0.001) in myopic children when compared with a non-myopic pediatric population. However, it seems that there is not a correlation among the three OCT parameters studied, age and sex, when they are analyzed depending on refractive error.

Effect of keratorefractive surgery on choroidal thickness in anisometropic amblyopia

PURPOSE

To evaluate postoperative change in choroidal thickness (CT) in patients with anisometropic amblyopia undergoing keratorefractive surgery.

METHODS

Anisometropic amblyopic patients and nonamblyopic patients who underwent keratorefractive surgery were included in the study. The eyes were divided into three groups. Group 1 consisted of eyes with anisometropic amblyopia, group 2 were the nonamblyopic fellow eyes, and group 3 (control group) were nonamblyopic eyes which had undergone keratorefractive surgery. At the third postoperative month, the CT of these eyes were measured by Enhanced Depth Imaging OCT (EDI-OCT). The choroidal thickness (CT) was measured in the subfoveal area and at 500 micron intervals nasally and temporally.

RESULTS

Twenty-three anisometropic amblyopia patients with amblyopic and fellow eyes and 23 control eyes were enrolled. The mean subfoveal choroidal thickness (CT) was 387.3±168.8μm in group 1, 412.2±88.8μm in group 2 and 337.3±99μm in group 3 (P: 0.019). Group 1 and group 2 showed higher choroidal thickness (CT) in the nasal and temporal quadrants than group 3 (P: 0.03, P: 0.04). At the third postoperative month, central foveal choroidal thickness was 356.6±115.5μm in group 1, 375.1±112.5μm in group 2 and 284.4±98.9μm in group 3 (P: 0.071). Choroidal thickness (CT) in the nasal and temporal quadrants at the third postoperative month was also similar (P: 0.210, P: 0.103).

CONCLUSIONS

The macular choroid is thicker in amblyopic eyes and non-amblyopic fellow eyes than in the nonamblyopic controls. Improved fixation after refractive surgery may normalize CT.

Choroidal thickness and ocular growth in childhood

The involvement of the choroid in ocular growth regulation has been postulated in studies showing that refractive errors correlate with alterations in choroidal thickness (ChT). The advent of optical coherence tomography imaging has enabled qualitative and quantitative assessment of the choroid. In children, ChT changes correlate with a number of ocular pathologies, including myopia, retinopathy of prematurity, and amblyopia. We synthesize mechanisms and evidence regarding choroidal thickness variation during childhood. Subfoveal ChT is influenced by a number of factors including age, ethnicity, gender, axial length, and intraocular pressure. Myopic eyes have thinner choroids compared to emmetropic and hyperopic eyes. ChT may in fact serve as a marker of myopic progression, as ChT thinning occurs early during myopic development, but this association has not been established quantitatively. In addition, subfoveal ChT appears thicker in amblyopic eyes, while prematurity and retinopathy of prematurity may be associated with thinner ChT. Overall, both animal models and clinical research indicate that ChT induces or reflects physiological changes in the eye pertaining to ocular growth or maturation.

Comparison of Retinal Vascular Structure in Eyes With and Without Amblyopia by Optical Coherence Tomography Angiography

PURPOSE

To evaluate the retinal vascular structure in amblyopic eyes by optical coherence tomography angiography (OCTA).

METHODS

Thirty-seven eyes of 37 patients with anisometric amblyopia were compared with 37 eyes of 37 age- and gender-matched control subjects by OCTA in terms of superficial capillary plexus vessel density, deep capillary plexus vessel density, and foveal avascular zone.

RESULTS

The mean age was 12 ± 4.2 years in patients with amblyopia and 13 ± 6.1 years in individuals without amblyopia. Foveal superficial capillary plexus vessel densities were 20.49% ± 3.27%, 19.70% ± 3.82%, and 19.96% ± 3.84%, and parafoveal superficial capillary plexus vessel densities were 48.50% ± 3.64%, 49.01% ± 3.33%, and 48.9% ± 2.98% in amblyopic, fellow, and control eyes, respectively. The foveal deep capillary plexus vessel densities were 18.95% ± 3.76%, 18.6% ± 4.50%, and 19.29% ± 4.01%, and parafoveal deep capillary plexus vessel densities were 51.0% ± 4.21%, 51.85% ± 4.12%, and 52.03% ± 3.57% in amblyopic, fellow, and control eyes, respectively. Superficial and deep capillary plexus vessel densities in the foveal and parafoveal areas were not significantly different between the groups (P > .05). The parafoveal area was evaluated in quadrants. In the superior quadrant, superficial and deep capillary plexus parafoveal densities were significantly lower in amblyopic eyes (P < .05). No significant difference was observed in the foveal avascular zone between the groups (P > .05).

CONCLUSIONS

Although no significant vascular damage was demonstrated by OCTA in amblyopic eyes, localized defects may be specific for it. Additional studies are needed to evaluate any specific localization of vascular damage related to amblyopia. [J Pediatr Ophthalmol Strabismus. 2020;57(1):48-53.].

Analysis of Choroidal Vascularity in Children with Unilateral Hyperopic Amblyopia

This institutional case control study was carried out to compare choroidal vascularity (CV) in amblyopic eyes, fellow eyes, and control eyes in children with unilateral hyperopic amblyopia. Sixty-four eyes of 32 childeren with unilateral anisometropic hyperopic amblyopia and 38 eyes of 19 healthy children (controls), aged 3 to 16 years. Subfoveal choroidal thickness (CT) and CV were measured using spectral domain optical coherence tomography. The mean subfoveal CT of amblyopic eyes (338.9 ± 60.0 μm) was greater than that of fellow eyes (315.3 ± 63.3 μm, P = 0.043) and control eyes (313.0 ± 42.1 μm, P = 0.025). The mean CV of amblyopic eyes (0.715 ± 0.020) was greater than that of control eyes (0.700 ± 0.020, P < 0.001). While a positive correlation between CT and CV was found in normal eyes (r = 0.470, P = 0.004), a strong negative correlation existed in amblyopic eyes (r = −0.684, P < 0.001). In conclusion, although mean CV was higher in amblyopic eyes, the negative correlation between CT and CV may suggests insufficient blood supply to the outer retina and choroid in the affected eyes of patients with unilateral anisometropic hyperopic amblyopia.

Evaluation of choroidal thickness in amblyopia using optical coherence tomography

Objective:

To investigate the choroidal thickness in children with amblyopia through spectral-domain optical coherence tomography.

Methods:

A total of 31 children with unilateral amblyopia and 31 right eyes of controls with normal vision were enrolled in the study. The choroidal thickness was measured directly below the fovea and at 12 other locations: 1, 2 and 3 mm superior, temporal, inferior, and nasal to the fovea. All the parameters were compared between amblyopic eyes, fellow eyes, and control eyes.

Results:

The mean subfoveal choroidal thickness was 398.03 ± 74.60, 354.13 ± 81.78, and 328.12 ± 65.93 μm in amblyopic eyes, fellow eyes, and control eyes, respectively. Significant difference was found in choroidal thickness among three groups at subfoveal choroidal thickness, N1, and S1 using multivariate analysis of covariance after adjusting for axial length. Significant negative correlation was found only between subfoveal choroidal thickness and axial length in amblyopic eyes (r = –0.463, p = 0.01).

Conclusion:

The subfoveal choroid is significantly thicker in amblyopic eyes than control eyes only at subfoveal choroidal thickness, N1, and S1. The choroidal thickness was thickest in the subfoveal region and thinnest in the nasal region. There are other changes in choroidal structure associated with amblyopia.

Abnormal Outer Choroidal Vasculature in Amblyopia

PURPOSE

Several studies have indicated morphological changes in the choroid in amblyopia cases. This study investigates whether choroidal vasculature was different among amblyopic and fellow eyes in unilateral amblyopia patients and healthy eyes, using en face images acquired via swept-source optical coherence tomography (SS-OCT).

DESIGN

Prospective, observational case-control study.

METHODS

This study included 14 consecutive patients with unilateral amblyopia and 22 age- and axial length-matched healthy eyes. Using SS-OCT, we obtained en face images of choroidal vasculature midway through the subfoveal inner and total choroid, corresponding to the vasculature of the choriocapillaris and Sattler's layer (inner choroid) and Haller's layer (outer choroid), respectively. We analyzed the en face images of the inner and outer choroidal vascular areas in 3 × 3 mm squares adjusted from 6 × 6 mm squares, using Littmann's magnification correction, after binarization of the images as a portion of the whole area.

RESULTS

The outer choroidal vascular areas were larger in both amblyopic and fellow eyes than in healthy eyes (both P < 0.001), although there were no significant differences in inner (56.35 ± 2.46% and 56.27 ± 3.75%, respectively) or outer (61.49 ± 4.95% and 61.48 ± 3.73%, respectively) choroidal vascular area between amblyopic and fellow eyes (P=0.98  and  0.91, respectively). An outer choroidal vascular area of 59% was set as an appropriate cutoff value for distinguishing patients from controls.

CONCLUSIONS

The outer choroidal vascular area was larger in both amblyopic eyes and fellow eyes compared to healthy eyes. Our findings may help clarify the etiology of amblyopia.

Analysis of Peripapillary Choroidal Thickness in Unilateral Amblyopia

Purpose:

To evaluate the peripapillary choroidal thickness (CT) in children with unilateral amblyopia using spectral-domain optical coherence tomography (SD-OCT).

Methods:

One hundred and six eyes of 53 children with unilateral amblyopia and 20 eyes of 20 children with normal vision were involved in this study. Of the 53 children with unilateral amblyopia, 29 (54.7%) had hyperopic anisometropic amblyopia and 24 (45.3%) had strabismic amblyopia. Peripapillary CT was measured from 6 mm length radial B-scans at the optic nerve head using the enhanced depth imaging program of an SD-OCT (Heidelberg Engineering, Germany). Age, sex, refractive error, and best-corrected visual acuity were also recorded.

Results:

The average peripapillary CT was greater in amblyopic eyes than in the fellow eyes of the children with amblyopia (P = 0.002), and control eyes (P < 0.001). There was no significant difference between the fellow eyes of children with amblyopia and the control eyes (P = 0.158). The average peripapillary CT was negatively correlated with axial length (AL) in amblyopic eyes (r = -0.381; P = 0.005) and fellow eyes (r = -0.392; P = 0.004) but not in control eyes (r = -0.232; P = 0.325). After adjustment for the possible effects of AL, the average peripapillary CT in amblyopic eyes was still greater than in fellow eyes (P = 0.014) and control eyes (P = 0.022).

Conclusion:

The peripapillary choroid of eyes with amblyopia was thicker than that of the fellow eyes and control eyes. No significant difference was observed between fellow eyes and control eyes.

CAN Optical Coherence Tomography redefine amblyopia?

Introduction: For many years, amblyopia was regarded as a disorder of the visual system in which an organic cause could not be identified. Optical Coherence Tomography opens new horizons in understanding the etiopathology of amblyopia and seems to highlight morphologic anomalies in the retina of the amblyopic eye.

Purpose: The objective of this paper is to analyze the macular thickness, optic nerve changes, and choroidal thickness found in patients diagnosed with amblyopia based on trials reported in the literature.

Material and methods: This study analyzes 30 clinical trials regarding amblyopia evaluation with Optical Coherence Tomography. The research articles analyzed were published between 2006 - 2016 and were identified on PubMed database.

Results: 19 research studies focused on macular and nerve optic changes, 7 on choroidal changes and 6 on retinal changes after occlusion. The results were discussed according to the type of amblyopia, alteration of macular thickness, optic nerve changes, ganglion cell layer changes, and alteration of choroidal thickness.

Conclusions: The results are of great variability, and it seems that macula and choroid involvement is more frequently suggested compared with optic nerve involvement.

Abbreviations: OCT = Optical Coherence Tomography, RNFL = Retinal Nerve Fiber Layer, GCC = Ganglion Cell Complex, ACD = Anterior Chamber Depth, BCVA = Best Corrected Visual Acuity

Macular retinal and choroidal thickness in unilateral amblyopia using swept-source optical coherence tomography

Background

To investigate macular retinal and choroidal thickness in amblyopic eyes compared to that in fellow and normal eyes using swept-source optical coherence tomography (SS-OCT).

Methods

This study examined 31 patients with hyperopic anisometropic amblyopia (6.9 ± 3.8 years, mean ± standard deviation), 15 patients with strabismic amblyopia without anisometropia (7.9 ± 4.2 years), and 24 age-matched controls (7.8 ± 3.3 years). Retinal and choroidal thickness was measured by 3D scans using SS-OCT. A 6-mm area around the fovea was automatically analyzed using the Early Treatment Diabetic Retinopathy Study map. The thickness from SS-OCT was corrected for magnification error using individual axial length, spherical refraction, cylinder refraction, and corneal radius. Retinal thickness was divided into the macular retinal nerve fiber layer (mRNFL), ganglion cell layer + inner plexiform layer (GCL+IPL), ganglion cell complex (GCC), and the inner limiting membrane to the retinal pigment epithelium (ILM-RPE) thickness. Retinal and choroidal thickness was compared among amblyopic, fellow, and normal eyes.

Results

In both amblyopia groups, there was no significant difference in the mRNFL, GCL+IPL, and GCC thicknesses among the amblyopic, fellow, and control eyes. In the anisometropic amblyopia group, choroidal thickness (subfovea, center 1 mm, nasal and inferior of the inner ring, nasal of the outer ring, and center 6 mm) of amblyopic eyes were significantly greater than that of fellow and normal eyes. In contrast, none of the choroidal thicknesses were significantly different among the investigated eyes in the strabismic amblyopia group.

Conclusions

We found no significant difference in inner retinal thickness in patients with unilateral amblyopia. Although there were significant differences in choroidal thickness with hyperopic anisometropic amblyopia, there was no significant difference for the strabismic amblyopia. The discrepancy in choroidal thickness between the two types of amblyopia may be due to both differences in ocular size and underlying mechanism.

A Meta-Analysis of Choroidal Thickness Changes in Unilateral Amblyopia

PURPOSE

To date, the topic of amblyopic changes remains controversial. Therefore, a systematic review and meta-analysis were carried out to evaluate choroidal changes in unilateral amblyopia.

METHODS

Major literature databases were searched for amblyopia-relevant studies. Using enhanced depth imaging optical coherence tomography (EDI-OCT), the primary outcome parameters examined were subfoveal choroidal thickness (SFCT) and different choroidal thickness (CT) positions. Efficacy estimates were evaluated by weighted mean difference (WMD) and 95% confidence interval (CI) for choroidal-associated changes. We performed subgroup analysis and metaregression analysis to examine potential sources of heterogeneity.

RESULTS

Eleven cross-sectional studies that included a total of 768 participants were identified. The amblyopic eye SFCT was thicker than that of the fellow and control (normal) eyes (WMD_{amblyopia versus fellow} = 49.24, 95% CI of 30.22 to 68.27, p < 0.001; WMD_{amblyopia versus control} = 54.51, 95% CI of 32.17 to 76.85, p < 0.001). There were no differences between the fellow and control eyes (WMD = 13.81, 95% CI of 1.16 to 28.77, p = 0.071). Subgroup and metaregression analyses indicated that the OCT type was the main source of heterogeneity.

CONCLUSIONS

The CT in the amblyopic eyes was thicker than that in the fellow and control eyes.

Comparison of quantitative measurement of foveal avascular zone and macular vessel density in eyes of children with amblyopia and healthy controls: an optical coherence tomography angiography study

PURPOSE

To quantify vessel density of superficial capillary plexus (SCP), deep capillary plexus (DCP), and the foveal avascular zone (FAZ) of children's amblyopic eyes and to compare the measurements with those of companion eyes and age-matched controls.

METHODS

Fifteen patients with strabismic amblyopia, and 15 age-matched controls were included in this cross-sectional study. SCP, DCP, and FAZ were measured via optical coherence tomographic angiography (OCTA).

RESULTS

Mean subject age was 8.2 ± 2.3 years in the amblyopia group and 8.6 ± 2.2 years in the control group. The mean SCP at 1 mm, 2 mm, and 3 mm zones were (in the order amblyopic eye, companion eye, control) 1.399 ± 0.088, 5.854 ± 0.195, 12.866 ± 0.346; 1.467 ± 0.084, 5.979 ± 0.182, 12.965 ± 0.321; and 1.559 ± 0.052, 6.343 ± 0.190, 13.819 ± 0.423. SCP was significantly lower in amblyopic eyes than in companion eyes and controls (P < 0.05). The mean DCP at 1 mm, 2 mm, and 3 mm zones were 1.425 ± 0.069, 6.038 ± 0.186, 13.522 ± 0.336; 1.525 ± 0.072, 6.427 ± 0.190, 14.286 ± 0.322; and 1.685 ± 0.074, 6.895 ± 0.198, 15.355 ± 0.356. DCP was significantly lower in amblyopic eyes than companion eyes and controls (P < 0.05). The mean superficial FAZ were 0.287 ± 0.091, 0.262 ± 0.092, and 0.280 ± 0.097. The mean deep FAZ were 0.382 ± 0.092, 0.335 ± 0.080, and 0.329 ± 0.085. There was no significant difference in FAZ among groups (P > 0.05).

CONCLUSIONS

Vessel density of SCP and DCP of eyes with amblyopia is lower than that of the companion eye and the age-matched controls.

Choroidal Changes in Anisometropic and Strabismic Children With Unilateral Amblyopia

BACKGROUND AND OBJECTIVE

To detect changes in the choroidal layer at the macular area in amblyopic eyes.

PATIENTS AND METHODS

A cross-sectional study of 50 amblyopic patients (20 strabismic and 30 anisometropic) and 50 controls was done. Cross-sectional images using enhanced depth optical coherence tomography (OCT) were taken. Thicknesses were measured subfoveally and at 1,500 µm nasally, temporally, inferiorly, and superiorly. Submacular corresponding choroidal areas were also computed. Parameters were compared between amblyopic eyes, fellow eyes, and controls.

RESULTS

Significantly thicker choroid was detected in the subfoveal, temporal, and nasal locations (P = .007, .009, and .01, respectively) in amblyopic compared to fellow eyes; areas were also significantly greater temporally, nasally, and inferiorly. Significant differences in all choroidal measurements were found between amblyopic eyes and controls; these persisted only in the anisometropic subgroup.

CONCLUSION

Using enhanced depth OCT, the choroid of amblyopic eyes was observed to be thicker compared to normal fellow eyes and controls. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:900-907.].

Influence of Hyperopia and Amblyopia on Choroidal Thickness in Children

Purpose

To compare subfoveal choroidal thicknesses (ChTs) of anisometropic hyperopic amblyopic, hyperopic nonamblyopic, and emmetropic control eyes and to investigate the associations between ChT and ambylopia, spherical equivalent (SE), and axial length in the pediatric population.

Methods

Forty-six hyperopic nonamblyopic (hyperopic group), 33 anisometropic hyperopic amblyopic (amblyopic group), and 42 emmetropic (emmetropic group) eyes were enrolled in this cross-sectional comparative study. Enhanced depth imaging spectral-domain optical coherence tomography was used for quantitative analysis of subfoveal ChT. ChT was quantified manually as the distance between the hyperreflective line corresponding to the retinal pigment epithelium and the chorioscleral interface at the subfoveal area.

Results

The mean age was 10.6 ± 3.3 years (range 5-17) in the hyperopic group, 10.7 ± 3.3 years (range 5-17) in the amblyopic group, and 11.2 ± 3.3 years (range 5-17 years) in the emmetropic group (p = 0.627). The hyperopic and amblyopic groups had significantly thicker choroid compared to the emmetropic group (p1 = 0.005 and p2 = 0.006, respectively). However, there was no significant difference between the hyperopic and amblyopic groups concerning subfoveal ChT (p = 0.857). In addition, covariance analysis showed that although SE was independently associated with subfoveal ChT (p = 0.014), amblyopia had no significant independent effect on subfoveal ChT (p = 0.671). Further, subfoveal ChT had weak correlations with the axial length (r = −0.297, p = 0.001) and SE (r = 0.274, p = 0.002).

Conclusions

Hyperopia was associated with subfoveal ChT, whereas amblyopia had no independent significant effect on subfoveal ChT in our study population.