Incidence of fovea plana in normal children

Multimodal phenotyping of foveal hypoplasia in albinism and albino-like conditions: a pediatric case series with adaptive optics insights

Aim of the present study is to evaluate the relationship between genetic and phenotypic data in a series of patients affected by grade I and II of foveal hypoplasia with stable fixation and good visual acuity using multimodal imaging techniques. All patients underwent complete clinical and instrumental assessment including structural Optical Coherence Tomography (OCT), OCT Angiography and Adaptive Optics (AO) imaging. Central macular thickness (CMT), inner nuclear layer (INL), vessel density in superficial capillary plexus were the main variables evaluated with OCT technology. Cone density, cone spacing, cone regularity, cone dispersion and angular density were the parameters evaluated with AO. Genetic evaluation and trio exome sequencing were performed in all affected individuals. Eight patients (3 males and 5 females) with a mean age of 12.62 years (range 8-18) were enrolled. The mean best corrected visual acuity (BCVA) was 0.18 ± 0.13 logMAR, mean CMT was 291.9 ± 16.6 µm and INL was 26.2 ± 4.6 µm. The absence of a foveal avascular zone (FAZ) was documented by examination of OCT-A in seven patients in the superficial capillary plexus. However, there was a partial FAZ in the deep plexus in patients P5 and P8. Of note, all the patients presented with major retinal vessels clearly crossing the foveal center. All individuals exhibited a grade I or II of foveal hypoplasia. In 5 patients molecular analyses showed an extremely mild form of albinism caused by compound heterozygosity of a TYR pathogenic variant and the hypomorphic p.[Ser192Tyr;Arg402Gln] haplotype. One patient had Waardenburg syndrome type 2A caused by a de novo variant in MITF. Two patients had inconclusive molecular analyses. All the patients displayed abnormalities on OCT-A. Photoreceptor count did not differ from normal subjects according to the current literature, but qualitative analysis of AO imaging showed distinctive features likely related to an abnormal pigment distribution in this subset of individuals. In patients with foveal hypoplasia, genetic and multimodal imaging data, including AO findings, can help understand the physiopathology of the foveal hypoplasia phenotype. This study confirms that cone density and visual function can both be preserved despite the absence of a pit.

Abnormal foveal morphology in carriers of oculocutaneous albinism

BACKGROUND/AIMS

To investigate the foveal morphology in carriers of oculocutaneous albinism (OCA) using spectral domain optical coherence tomography (SD-OCT). A cross-sectional, observational study.

METHODS

Handheld SD-OCT (Envisu C2300) was used to acquire horizontal scans through the centre of the fovea in biological parents of patients with OCA (n=28; mean age±SD=40.43±8.07 years) and age-matched and ethnicity-matched controls (n=28; mean age±SD=38.04±10.27 years). Sequence analysis was performed for variants in known genes associated with OCA. Best-corrected visual acuity (BCVA), presence of foveal hypoplasia and grade, foveal, parafoveal and perifoveal thickness measurements of total retinal layers (TRL), inner retinal layers (IRL) and outer retinal layers (ORL) thickness were measured.

RESULTS

Foveal hypoplasia was identified in 32.14% of OCA carriers; grade 1 in all cases. OCA carriers demonstrated significant thicker TRL thickness (median difference: 13.46 µm, p=0.009) and IRL thickness (mean difference: 8.98 µm, p<0.001) at the central fovea compared with controls. BCVA of carriers was between -0.16 and 0.18 logMAR (mean: 0.0 logMAR). No significant differences in BCVA was noted between OCA carriers or controls (p=0.83). In the OCA carriers, we identified previously reported pathogenic variants in TYR, OCA2 and SLC45A2, novel OCA2 variants (n=3) and heterozygosity of the pathogenic TYR haplotype.

CONCLUSION

We have, for the first time, identified foveal abnormalities in OCA carriers. This provides clinical value, particularly in cases where limited phenotype data are available. Our findings raise the possibility that previously reported mild cases of foveal hypoplasia or isolated foveal hypoplasia could correspond to OCA carrier status.

Characterizing Foveal Hypoplasia Using Optical Coherence Tomography Angiography: Evaluation of Microvascular Abnormalities and Clinical Significance

This study aimed to evaluate foveal avascular zone (FAZ) features and macular flow density (FD) in various retinal layers in a cohort of patients with foveal hypoplasia (FH) using optical coherence tomography angiography (OCTA), in order to characterize microvascular abnormalities and explore their potential clinical significance. FAZ parameters and FD, as well as retinal thickness and volume values were analyzed and compared between patients with FH and an age- and gender-matched control cohort. Correlations between disease severity and visual acuity (VA), as well as between disease severity and FAZ features were evaluated. A total of 19 eyes with FH and 19 control eyes were included. The study group showed significantly higher FD values in the foveal sectors of the superficial and deep capillary plexus compared to controls. FAZ area, perimeter, and acircularity index (ACI) were noticeably altered in eyes with FH; however, they did not correlate with disease severity. Visual acuity was negatively correlated with disease severity. The results of this study provide evidence of altered microvasculature architecture specifically in the foveal sectors of patients with FH. The higher FD values in the foveal sectors of FH patients suggest a potential compensatory response of the retinal microvasculature. FAZ parameters and FD values of the foveal sectors could be used as part of an OCTA-based grading system in FH patients.

Atypical Foveal Hypoplasia in Best Disease

PURPOSE

To determine the prevalence and characteristics of foveal hypoplasia (also called fovea plana) in patients with Best disease using spectral-domain (SD) optical coherence tomography (OCT) and OCT-angiography (OCT-A).

DESIGN

A retrospective observational study including patients diagnosed with Best disease.

SUBJECTS AND PARTICIPANTS

Fifty-nine eyes of thirty-two patients (fifteen females (46.9%) and seventeen males (53.1%), p = 0.9) diagnosed with Best disease were included. Patients' eyes were categorized into two groups: Eyes with a fovea plana appearance ('FP group') and eyes without fovea plana appearance ('no FP group'), based on the foveal appearance on B-scan SD-OCT.

METHODS AND MAIN OUTCOME MEASURES

Cross-sectional OCT images were assessed for the persistence of inner retinal layers (IRL) and OCT-A was analyzed for the presence of a foveal avascular zone (FAZ), the size of which was determined when applicable.

RESULTS

Overall, 16 eyes (27.1%) of 9 patients had a fovea plana appearance ('FP group') with the persistence of IRL, and 43 eyes (72.9%) of 23 patients did not have fovea plana appearance ('no FP group'). Among FP eyes, OCT-A performed in 13 eyes showed bridging vessels through the FAZ in 100% of eyes with OCT-A. Using Thomas classification, 14 out of the 16 eyes with fovea plana (87.5%) had atypical foveal hypoplasia, and the 2 others (12.5%) had a grade 1b fovea plana.

CONCLUSION

In our series, foveal hypoplasia was present in 27.1% of patients with Best disease. OCT-A showed bridging vessels through the FAZ in all eyes. These findings highlight the microvascular changes associated with Best disease, which can be an early sign of the disease in patients with a family history.

Incidence and clinical significance of fovea plana in the French population with age-related cataract

BACKGROUND

Fovea plana is defined as an immature macula diagnosed by OCT, showing the unusual shunt of the inner retinal layers into the fovea. The incidence of fovea plana in the adult population remains to be determined. The aim of this study was to determine the incidence of fovea plana in the French population with age-related cataract.

METHODS

Consecutive patients who underwent cataract surgery in Rothschild Foundation Hospital, France, between January and March 2021, with preoperative analyzable OCT scans available, were retrospectively screened in order to determine the incidence of fovea plana in these population. Ophthalmological characteristics of patients were reported, and detailed.

RESULT

Fovea plana was encountered in 20 out of 204 patients during the 3 months corresponding to an incidence of 9.8%. One of those patients had stage 2 fovea plana.

CONCLUSION

Although fovea plana is defined as an immature macula, it is not rare in preoperative population. This macular aspect was not associated with poor visual acuity in our cohort.

Foveal hypoplasia in parents of patients with albinism

BACKGROUND

Albinism is a group of genetic disorders characterized by general skin and retinal hypopigmentation. It is in most cases an autosomal recessive condition. Foveal hypoplasia (FH) is one of the main criteria for the diagnosis of albinism. The aim of this study was to analyze the macular profile of the parents of patients with albinism.

METHODS

This study included a case series of 27 patients with albinism seen in Rothschild Foundation between April 2017 and February 2020. Spectral-domain optical coherence tomography (SD-OCT) and OCT angiography (OCT-A) were performed in every patient when possible and in every available parents. FH was graded according to Thomas' classification based on OCT. Next generation sequencing-based gene panel testing was performed in parents and children when a FH was detected on OCT in a parent.

RESULTS

Twenty-seven patients with albinism were examined. Nine parents had FH based on the OCT B-scan (33%). In parents without FH based on the SD-OCT B-scan (67%), OCT-A showed a reduced avascular zone in the deep vascular plexus in 4 parents. Six parents carried variants that could explain their phenotype, including TYR R402Q hypomorphic alleles.

CONCLUSION

This study showed the presence of FH in parents of patients with albinism, and aimed to genetically explain this phenotype.

Optical Coherence Tomography as a Biomarker for Differential Diagnostics in Nystagmus: Ganglion Cell Layer Thickness Ratio

In albinism, with the use of optical coherence tomography (OCT), a thinning of the macular ganglion cell layer was recently reported. As a consequence, the relevant OCT measure, i.e., a reduction of the temporal/nasal ganglion cell layer thickness quotient (GCLTQ), is a strong candidate for a novel biomarker of albinism. However, nystagmus is a common trait in albinism and is known as a potential confound of imaging techniques. Therefore, there is a need to determine the impact of nystagmus without albinism on the GCLTQ. In this bi-center study, the retinal GCLTQ was determined (OCT Spectralis, Heidelberg Engineering, Heidelberg, Germany) for healthy controls (n = 5, 10 eyes) vs. participants with nystagmus and albinism (Nalbinism, n = 8, 15 eyes), and with nystagmus of other origins (Nother, n = 11, 17 eyes). Macular OCT with 25 horizontal B scans 20 × 20° with 9 automated real time tracking (ART) frames centered on the retina was obtained for each group. From the sectoral GCLTs of the early treatment diabetic retinopathy study (ETDRS) circular thickness maps, i.e., 3 mm and 6 mm ETDRS rings, GCLTQ I and GCLTQ II were determined. Both GCLTQs were reduced in Nalbinism (GCLTQ I and II: 0.78 and 0.77, p < 0.001) compared to Nother (0.91 and 0.93) and healthy controls (0.89 and 0.95). The discrimination of Nalbinism from Nother via GCLTQ I and II had an area under the curve of 80 and 82% with an optimal cutoff point of 0.86 and 0.88, respectively. In conclusion, lower GCLTQ in Nalbinism appears as a distinguished feature in albinism-related nystagmus as opposed to other causes of nystagmus.

Segmentation of the foveal and parafoveal retinal architecture using handheld spectral-domain optical coherence tomography in children with Down syndrome

BACKGROUND

Down syndrome is a common multigene, multisystem disorder associated with abnormalities of visual function and characteristic changes in the majority of tissues in the eye. Historic descriptions of macular structure in Down syndrome have been variable, but optical coherence tomography allows increasingly detailed characterization of retinal architecture in vivo. We demonstrate the feasibility of retinal imaging in children with Down syndrome using handheld OCT in an outpatient clinical setting, and describe the foveal and parafoveal retinal architecture in this group.

METHODS

Fourteen White British children aged between 4 and 11 with Down syndrome were recruited to have handheld SD-OCT retinal imaging performed at a single centre in an outpatient clinical setting. The thickness of the retinal layers at the fovea and parafovea was analysed using segmentation software, and compared with age-matched controls from a previously published normative UK dataset.

RESULTS

Sixty-seven percent of the children studied had grade 1 foveal hypoplasia. At the fovea, the ganglion cell layer (p = 0.002) and inner nuclear layer (p < 0.001) were thickened relative to the control group. At the parafovea, there was thickening of the retina attributable to numerous layers in both the inner and outer retina, which remained significant after Bonferroni correction.

CONCLUSION

OCT imaging of children with Down syndrome in an outpatient setting is feasible. There is a high incidence of foveal hypoplasia in this group, associated with thickening of the ganglion cell and inner nuclear layers at the fovea.

Structural, Microvascular, and Functional Findings Associated with Fovea Plana

PURPOSE

To analyse structural (OCT), microvascular (OCTA), and functional changes (BCVA, mfERG) associated with fovea plana and to compare it to healthy controls.

METHODS

A retrospective observational study was performed on 13 patients (26 eyes; aged 34.46 y ± 20.26) with a clinical picture of fovea plana and 15 controls (30 eyes; aged: 41.47 y ± 14.03).

RESULTS

In fovea plana, BCVA ranged from 0.25 to 1.0, with a spherical error of - 5.5 to + 18.0 dpt. Posterior segment changes included elevated papillomacular retinal fold, uveal effusion syndrome, crowded optic discs, and hypopigmented fundus. OCTA imaging of the superficial (FAZ-S), intermediate (FAZ-I), and deep foveal avascular zone (FAZ-D) confirmed absence of foveal avascular zone (FAZ-S in 13 eyes, FAZ-I in 21 eyes, and FAZ-D in 10 eyes). Fovea plana patients had a significantly smaller FAZ-S, FAZ-I, and FAZ-D than controls (p < 0.001). Within the fovea plana group, a smaller FAZ-S correlated with reduced BCVA (p = 0.004) and with reduced mfERGs in zones 1 and 2 (p = 0.001 and p = 0.017). Also, a smaller FAZ-D showed positive correlations with the mfERG, with statistically significant values in zones 1 and 2 (p = 0.003 and p = 0.017).

CONCLUSION

In conclusion, our results confirm an altered structural, microvascular, and functional pattern in patients with a clinical picture of fovea plana. As documented by the functional microvascular interactions in our study, the developmental arrest in foveation reflects the functional maturation by means of visual acuity and central retinal function.

Comparison of OCT imaging in children with foveal hypoplasia born full term versus preterm

PURPOSE

It is unknown if foveal hypoplasia in full-term born children differs in structure and function from that observed in children born preterm. We compared macular structure and visual function in children with history of prematurity and full-term children diagnosed with foveal hypoplasia.

METHODS

We compared three groups of subjects (3-18 years old): (1) full-term hypoplasia (FH, n = 56, gestational age ≥ 36 weeks); (2) preterm hypoplasia (n = 57, gestational age ≤ 31 weeks, birth weight ≤ 1500 g); (3) control (n = 54), full-term normal. Using spectral-domain optical coherence tomography volume-scan images, macular structure within 3 mm of Early-Treatment-Diabetic-Retinopathy-Study circle was segmented. Total, inner, and outer foveal thickness of right eyes were compared. Foveal hypoplasia was graded according to the Leicester Grading System.

RESULTS

The mean total foveal thickness in micrometers was 263 ± 19 for the control, 299 ± 30 for the full-term hypoplasia, and 294 ± 28 for the preterm hypoplasia groups (F = 33, p < 0.001). Foveal inner retinal layer thickness differed among groups (p < 0.001), but not in the outer layers (p = 0.10). The full-term hypoplasia group had significantly thicker foveal inner layers (p < 0.05) and greater frequency of higher-grade hypoplasia than the preterm hypoplasia group. LogMAR visual acuity was worse in the full-term hypoplasia group (0.35 ± 0.36) than in the preterm hypoplasia group (0.19 ± 0.27, p < 0.001).

CONCLUSION

Fovea was thicker in both hypoplasia groups. The full-term hypoplasia group is associated with more severe structure changes and poorer visual function than the preterm hypoplasia group.

Morphology of foveal hypoplasia: Hyporeflective zones in the Henle fiber layer of eyes with high-grade foveal hypoplasia

Background

Foveal hypoplasia is characterized by the persistance of inner retinal layers at the macular center. We evaluated using spectral-domain optical coherence tomography (SD-OCT) morphological parameters of the macular center of eyes with foveal hypoplasia and describe the presence of hyporeflective zones in the Henle fiber layer (HFL) of eyes with high-grade foveal hypoplasia.

Methods

Eyes with foveal hypoplasia were classified into two groups: high-grade foveal hypoplasia with thick inner retinal layers at the macular center (thickness above 100 μm; 16 eyes of 9 subjects) and low-grade foveal hypoplasia with thinner inner retinal layers at the macular center (thickness below 100 μm; 25 eyes of 13 subjects). As comparison, SD-OCT images of normal control eyes (n = 75) were investigated.

Results

Eyes with foveal hypoplasia displayed shorter central photoreceptor outer segments (POS), a thinner central myoid zone, and a thicker central HFL compared to control eyes. Eyes with high-grade foveal hypoplasia also displayed a thinner central outer nuclear layer (ONL) compared to eyes with low-grade foveal hypoplasia and control eyes. There was a negative correlation between the thicknesses of the central ONL and HFL in eyes with foveal hypoplasia; however, the total thickness of both ONL and HFL was similar in all eye populations investigated. Visual acuity of subjects with foveal hypoplasia was negatively correlated to the thickness of the central inner retinal layers and positively correlated to the length of central POS. In contrast to central POS, the length of paracentral POS (0.5 and 1.0 mm nasal from the macular center) was not different between the three eye populations investigated. The paracentral ONL was thickest in eyes with high-grade foveal hypoplasia and thinnest in control eyes. Hyporeflective zones in the HFL were observed on SD-OCT images of eyes with high-grade foveal hypoplasia, but not of eyes with low-grade foveal hypoplasia and control eyes. OCT angiography images recorded at the level of the HFL of eyes with high-grade foveal hypoplasia showed concentric rings of different reflectivity around the macular center; such rings were not observed on images of eyes with low-grade foveal hypoplasia and control eyes.

Conclusions

It is suggested that the hyporeflective zones in the HFL of eyes with high-grade foveal hypoplasia represent cystoid spaces which are surrounded by Henle fiber bundles. Cystoid spaces are likely formed because there are fewer Henle fibers and a thinner central ONL despite an unchanged thickness of both ONL and HFL. Cystoid spaces may cause the concentric rings of different reflectivity around the macular center in the HFL of eyes with high-grade foveal hypoplasia.

All retinas are not created equal: Fovea‐to‐macula thickness ratio and foveal microvasculature in healthy young children

Purpose

Markers for the relationships between structural and microvasculature measures given by optical coherence tomography angiography are necessary to increase the diagnostic and prognostic value of this technique. The aim of this study was to investigate relationships between structural and microvasculature measures around the fovea in healthy eyes of healthy children.

Methods

Observational cross‐sectional study involving children aged 8–17 years, born at full‐term, with no eye disease. The better of two 3 × 3 mm macular scans obtained with a Cirrus 5000HD‐OCT was analysed. Images were corrected for lateral magnification errors. Vessel density and perfusion were measured with ImageJ/Fiji software for the superficial capillary plexus. Structural measures including foveal and macular thicknesses were performed manually.

Results

The sample included 86 participants, 51 (59%) females. Mean age was 12.4 years (SD = 2.5); mean best‐corrected acuity was −0.10 logMAR (SD = 0.09); mean refractive error was +0.59 D (SD = 1.3) and mean axial length was 23.1 mm (SD = 0.86). Mean area of the foveal avascular zone (AFAZ) was 0.20 mm² (SD = 0.88); median fovea‐to‐macula thickness ratio (FMTR) was 0.63 (IQR = 0.08); mean central vessel density was 12.42 mm⁻¹ (SD = 2.78) and mean central perfusion was 38.66% (SD = 3.83). AFAZ was correlated with central vessel density (p < 0.001), perfusion (p < 0.001), foveal thickness (p < 0.001) and FMTR (p < 0.001). Central vessel density was correlated with foveal thickness (p < 0.001) and FMTR, (p = 0.01). Central perfusion was correlated with foveal thickness (p < 0.001) and FMTR, (p = 0.003).

Conclusion

In this study, foveal thickness, FMTR and foveal microvasculature measurements were correlated. Clinicians need to be aware that shallow foveal pits and persistent foveal microvasculature are likely to occur in optical coherence tomography angiography images. In healthy eyes from healthy children, an atypical high FMTR and a small AFAZ may be associated with incomplete foveal development. The mechanism and functional implications of this remain unknown.

IDIOPATHIC FOVEAL HYPOPLASIA: Quantitative Analysis Using Optical Coherence Tomography Angiography

PURPOSE

To evaluate vascular density (VD), fractal dimension, and skeletal density on optical coherence tomography angiography in eyes with idiopathic foveal hypoplasia (IFH).

METHODS

Patients presenting with IFH to Creteil University Eye Clinic between January 2015 and October 2018 and age-matched healthy controls were retrospectively evaluated. Vascular density, skeletal density, and fractal dimension analyses were computed on optical coherence tomography angiography superficial capillary plexa (SCP) and deep capillary plexa (DCP) images on the whole image using a custom algorithm. Vascular density on the central 1 mm and the peripheral 8 mm for the two groups was performed.

RESULTS

Thirty-six eyes of 21 patients (18 eyes with IFH and 18 control eyes) were included. A decrease of VD at the level of the SCP and DCP was found in eyes with IFH compared with healthy control eyes (P = 0.005 for VD at the level of the SCP and P = 0.003 for VD at the level of the DCP, respectively). On the central 1 mm, VD was decreased in healthy eyes (32.3% ± 4.8) at the level of the SCP compared to IFH eyes (55.6% ± 46.3) (P < 0.001). Skeletal density was decreased in IFH eyes in both SCP and DCP (P =< 0.001). Fractal dimension was lower in IFH eyes in both SCP and DCP (P < 0.001).

CONCLUSION

Vascular density, skeletal density, and fractal dimension are reduced at the level of SCP and DCP in patients with IFH compared with controls, reflecting a particular anatomical and vascular organization. Quantitative analysis using optical coherence tomography angiography could help to evaluate the severity of IFH.

FOVEA PLANA ON OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY: New Perspectives

PURPOSE

To report on the reliability of optical coherence tomography angiography (OCTA) to diagnose fovea plana.

METHODS

A retrospective, cross-sectional, case-control study included patients with foveal persistence of the inner retinal layers, confirmed by spectral domain OCT, and superficial capillary plexus (SCP) and deep capillary plexus foveal vascularization confirmed by OCTA. A healthy control group was selected. The best-corrected visual acuity was obtained. Spectral-domain OCT was used for measuring the outer nuclear layer thickness, and OCTA determined the foveal avascular zone, SCP, and deep capillary plexus vascular density.

RESULTS

Optical coherence tomography angiography reliability, based on all parameters, reached 97%, whereas based only on SCP vascular density 91%. The plana group (n = 57) differed significantly from the control group (n = 28) in terms of foveal avascular zone, SCP, and deep capillary plexus foveal vascular density (P < 0.005). Subjects with SCP foveal vascular density >30% or foveal avascular zone <0.1 mm2 had fovea plana. The best-corrected visual acuity of the plana group had no correlation with OCTA quantitative parameters (Pearson |r|<0.18, Spearman |r|<0.44).

CONCLUSION

Optical coherence tomography angiography has a high accuracy in diagnosing fovea plana, as its characteristics differ significantly from the normal population. The lack of correlation between the best-corrected visual acuity and OCTA parameters implies that reduced the best-corrected visual acuity is likely to result from coexistent diseases rather than from the foveal structure.

Effect of gestational age at birth, sex, and race on foveal structure in children

PURPOSE

Premature birth, race, and sex are contributing risk factors for retinopathy of prematurity (ROP) and have long-term impact on children's retinal structure. Few studies investigate impact of race and sex on macular structure in children born preterm. This study compared foveal structure in preterm and full-term children.

METHODS

Children aged 4-18 years were enrolled into three groups: (1) ROP-risk group (n = 81), born at < 32 weeks gestational age with and without history of ROP; (2) preterm group (n = 46), born at 32-36 weeks gestational age; and (3) control group (n = 68) with full-term birth. Using spectral-domain optical coherence tomography volume-scan images, foveal structure within 1-mm and 3-mm early treatment diabetic retinopathy study circular grid was measured and segmented. Total inner and outer retina thickness of the right eye was compared among the three groups.

RESULTS

The mean total foveal thickness (in microns) was 287 ± 26 for the ROP-risk group, 276 ± 19 for the preterm group, and 263 ± 20 for the control group (F = 26, p < 0.001). Foveal thickness of the ROP-risk group was significantly higher than that of the preterm group and the control group (all p < 0.05). Foveal thickness was thinner in black children than in white children and thinner in females than in males (all p < 0.001). A similar disparity in race and sex was found in the thickness of the inner and outer layers.

CONCLUSIONS

The fovea was significantly thicker in the ROP-risk group than the control group. Foveal thickness decreases with increased gestational age. Race and sex are significant factors in foveal structure in children.

Volume Rendering of Angiographic Optical Coherence Tomography Angiography in Fovea Plana and Normal Foveal Pit

This paper aims to study adaptative vascular arrangements in idiopathic fovea plana with volume-rendered optical coherence tomography angiography (OCTA). A retrospective review of two cases of idiopathic fovea plana (mean age: 26.5 years) and two age-matched controls imaged with OCTA was conducted using spectral-domain OCTA (RTVue XR Avanti, Optovue, Inc., Fremont, CA) equipped with the AngioVue software. Both en face OCTA slabs and OCTA b scans were processed through Fiji software (http://fiji.sc; software version 2.0.0-rc-68/1.52e), and then extracted as image sequences for volume rendering reconstructions using the ImageVis3D volume rendering system (3.1.0 release). Eyes with idiopathic fovea plana demonstrated a regular superficial vascular plexus connecting to a single vascular monolayer representing the deeper vascular plexuses. At this location, several vertical short path connections were demonstrated, in contraposition with normal eyes where short path connections were infrequently observed. Advances in three-dimensional OCTA reconstruction increase the understanding of vascular connections and arrangement in retinal plexuses and possible anatomical variations that cannot be detected with conventional two-dimensional b scans.

Macular Microvasculature and Associated Retinal Layer Thickness in Pediatric Amblyopia: Magnification-Corrected Analyses

Purpose

The purpose of this study was to characterize macular microvasculature and structural retinal layers using magnification-corrected optical coherence tomography angiography (OCTA) images in children with amblyopia.

Methods

This prospective cross-sectional study included 22 children with unilateral amblyopia (4–11 years of age) receiving spectral-domain OCTA. Vessel densities in foveal and parafoveal regions of the superficial capillary plexus (SCP) and deep capillary plexus (DCP) were measured in amblyopic and fellow eyes using a customized image analysis program correcting the scale of retinal image with axial length. Iowa Reference Algorithms (Iowa Institute for Biomedical Imaging) were used to measure mean thickness values of 10 intra-retinal layers rescaled for image size correction.

Results

Foveal and parafoveal vessel densities in amblyopic eyes were lower than that of the fellow eyes in the SCP (fovea: P = 0.006 and parafovea: P = 0.003) and the DCP (P = 0.024 and P = 0.025, respectively). Amblyopic eyes had significantly smaller foveal avascular zone (FAZ) area than fellow eyes (P < 0.001). There were significant differences in retinal layer thickness between paired eyes, particularly in the inner retina in both foveal and parafoveal regions; retinal nerve fiber layer (RNFL) (P = 0.024 and P = 0.095, respectively), ganglion cell layer (P < 0.001 and P = 0.008), inner plexiform layer (IPL; P = 0.12 and P = 0.037), inner nuclear layer (P = 0.005 and P = 0.005), and outer plexiform layer (OPL; P = 0.02 and P = 0.057), except in the foveal IPL, the parafoveal RNFL, and OPL.

Conclusions

Unilateral amblyopic eyes demonstrate reduced macular vessel density and thicker inner retinal layers compared with fellow eyes even after correcting for image magnification. Changes in macular microvasculature and structural layers may offer valuable insights in the development of amblyopia.

Axenfeld-Rieger syndrome combined with a foveal anomaly in a three-generation family: a case report

Background

Axenfeld-Rieger syndrome (ARS) is a rare autosomal dominant eye disorder that can also affect other organs of the human body. The condition is primarily characterized by the anterior segmental abnormalities of the eye. Here, we present an observational case series of a three-generation family with ARS and unexpected foveal anomaly.

Case presentation

A 33-year-old woman was admitted to an Ophthalmology Clinic in Bialystok for left eye congenital cataract surgery. The patient (proband) was diagnosed with visual deterioration, multiple defects of iris, corectopia, displacement of the Schwalbe’s line, and phenotypic characteristics of ARS. A perimetric examination indicated peripheral visual field loss and signs typical for glaucoma. Based on the phenotypic symptoms and genetic test, the patient was diagnosed with Axenfeld Rieger Syndrome. However, the optical coherence tomography of the macula showed foveal anomaly (absence of the physiological pit), which is not typically associated with this genetic disorder. The patient’s family history revealed that her two daughters were undergoing treatment for congenital glaucoma, and one of the daughters also had foveal anomaly the same as her mother. Interestingly, an examination of the patient’s mother showed typical phenotypic features of ARS such as a defect of the iris, posterior embryotoxon, and coloboma, as well as foveal anomaly. A genetic test confirmed PITX2 mutation in both, proband’s two daughters and mother.

Conclusions

This study highlights the occurrence of ARS with unusual ophthalmic features such as foveal anomaly (absence of the physiological pit) in a three-generation family. Although ARS is known to represent the developmental defects of the anterior segment of the eye, it is very important to perform fundus evaluation to identify associated posterior segment anomalies that may affect visual acuity. The presence of ocular defects not typically associated with ARS suggests a wide spectrum of mutations within PITX2 gene which are required to identify in order to determine genotype- phenotype correlation in ARS affected individuals.

Genetic causes of nystagmus, foveal hypoplasia and subnormal visual acuity- other than albinism

Background: To describe genetic molecular findings in individuals with congenital nystagmus, foveal hypoplasia, and subnormal vision, with normal ocular pigmentation (absence of diffuse transillumination or transparent retinal pigment typical for albinism).Methods: This is a retrospective, multicenter study of ophthalmic, systemic, and genetic features, as collected from medical records of patients diagnosed with infantile nystagmus and foveal hypoplasia. Ophthalmic findings include best-corrected visual acuity (BCVA), biomicroscopic examination, cycloplegic refraction, retinal examination, macular optical coherence tomography, and electroretinography. Genetic information was retrieved from the participating genetic clinics and included ethnicity and molecular diagnosis.Results: Thirty-one individuals met the inclusion criteria and had a secure molecular diagnosis. Mutations in two genes predominated, constituting 77.4% of all the represented genes: SLC38A8 (45.1%) and PAX6 (32.3%). Seventy-eight percent of the subjects who had a measurable BCVA had moderate and severe visual impairment (range 20/80 to 20/270). Most patients with a mutation in SLC38A8 had mild to moderate astigmatism, while most patients with PAX6 mutation had moderate and severe myopia. Patients in the PAX6 group had variable degrees of anterior segment manifestations.Conclusion: In our cohort, the main causative genes for congenital nystagmus and foveal hypoplasia in normally pigmented eyes were SLC38A8 and PAX6. A mild phenotype in PAX6 mutations may be an under-diagnosed cause of nystagmus and foveal hypoplasia. Reaching an accurate genetic diagnosis is essential for both the patients and their family members. This enables predicting disease prognosis, tailoring correct follow-up, and providing genetic counseling and family planning to affected families.

MACULAR MICROVASCULAR NETWORKS IN HEALTHY PEDIATRIC SUBJECTS

PURPOSE

To report optical coherence tomography angiography (OCTA) values in healthy pediatric eyes and to identify factors that may modify these values.

METHODS

In this prospective observational cross-sectional study, macular OCTA images were acquired from healthy pediatric patients. Main outcome measures were 1) foveal avascular zone (FAZ) area at the level of the superficial retinal capillary plexus (SCP); 2) SCP and deep retinal capillary plexus (DCP) perfusion density (based on the area of vessels); 3) SCP and DCP vessel density (based on a map with vessels of 1-pixel width); and 4) CC perfusion density. Multiple regression analysis was performed to assess the effect of age, sex, ethnicity, refraction, and foveal macular thickness (FMT) on OCTA parameters.

RESULTS

Seventy-seven eyes from 52 subjects (23 male and 29 female) were included in analysis. Mean age was 11.1 ± 3.3 years (range = 5.0-17.0 years). Twenty-nine (55.8%) subjects were white, 14 (27.0%) Hispanic, 8 (15.4%) Asian, and 1 (1.8%) African-American. Mean refraction was -0.1 ± 2.4 diopters (D) (range = -5.75 to +9.0 D). Mean FMT was 248.6 ± 18.6 μm. Larger FAZ area was significantly associated with older age (P = 0.014). Furthermore, larger FAZ area was associated with reduced FMT (P < 0.0001). Male sex was associated only with increased SCP perfusion density (P = 0.042). Increased CC perfusion density was associated with younger age (P = 0.022).

CONCLUSION

We report data for pediatric OCTA parameters in healthy subjects. Several variables influence the density of macular microvascular networks, and these factors should be considered in the OCTA study of pediatric eye disorders.

Multimodal Imaging in a Case of Fovea Plana Associated with Situs Inversus of the Optic Disc

Fovea plana is a congenital condition characterized by anatomic absence of the foveal pit. It may be isolated or associated with congenital ocular anomalies. In this report, we present a case of fovea plana associated with situs inversus of the optic disc, optic disc hypoplasia, tilted optic disc, and prepapillary vascular loop and with best corrected visual acuity of 20/32. The aim of this report is to demonstrate the coexistence of very rare multiple optic disc anomalies and fovea plana, and also to emphasize that the use of multimodal imaging methods facilitates the identification of rare anomalies.

Septo-optic dysplasia with fovea plana: A case report

Septo-optic dysplasia (SOD) is characterized by optic nerve hypoplasia, pituitary gland hypoplasia, and midline abnormalities of the brain. The phenotype of SOD is highly heterogeneous, and the existence of at least two features is considered sufficient for diagnosis. Fovea plana is the absence of a foveal pit in the central fovea, and despite being a developmental abnormality of the fovea, good visual acuity may be retained in some individuals. In this case, a 12-year-old female presented to the ophthalmology clinic with the complaint of blurred vision in her right eye. In dilated fundus examination, optic disc hypoplasia and no foveal light reflex were seen. Magnetic resonance imaging and optical coherence tomography revealed optic nerve, brain midline, and foveal abnormalities. The patient was diagnosed as having SOD with optic nerve hypoplasia and septum pellucidum agenesis, and fovea plana. Both SOD and fovea plana are rare conditions, and there are several reports in the literature that separately describe their clinical features. The most important aspect of this case report is to reveal the unusual co-existence of SOD and fovea plana in a young patient.

Distribution of macular ganglion cell layer thickness in foveal hypoplasia: A new diagnostic criterion for ocular albinism

Background/Aims

To analyse the distribution of macular ganglion cell layer thickness (GCLT) in patients with foveal hypoplasia (FH) with or without albinism to obtain new insights into visual pathway anomalies in albinos.

Methods

Patients with FH who presented at our institution between 2013 and 2018 were retrospectively drawn for analysis. Mean GCLT was calculated after automated segmentation of spectral domain-optical coherence tomography (SD-OCT) scans. Patients with FH due to albinism (n = 13, termed ‘albinism FH’) or other kinds (n = 10, termed ‘non-albinism FH’) were compared with control subjects (n = 15). The areas: fovea (central), parafovea (nasal I, temporal I) and perifovea (nasal II, temporal II) along the horizontal meridian were of particular interest. Primary endpoints of this study were the ratios (GCLT-I- and GCLT-II-Quotient) between the GCLT measured in the temporal I or II and nasal I or II areas.

Results

There was a significant difference between the GCLT-I-Quotient of healthy controls and albinism FH (p<0.001), as well as between non-albinism FH and albinism FH (p = 0.004). GCLT-II-Quotient showed significant differences between healthy controls and albinism FH (p<0.001) and between non-albinism FH and albinism FH (p = 0.006). The best measure for distinguishing between non-albinism FH and albinism FH was the calculation of GCLT-II-Quotient (area temporal II divided by area nasal II), indicating albinism at a cut-off of <0.7169. The estimated specificity and sensitivity for this cut-off were 84.6% and 100.0%, respectively. The estimated area under the curve (AUC) was 0.892 [95%CI: 0.743–1.000, p = 0.002].

Conclusion

Macular GCLT-distribution showed a characteristic temporal to central shift in patients with FH due to albinism. Calculation of the GCLT-II-Quotient at a cut-off of <0.7169 presents a new diagnostic criterion for identification of ocular albinism.

Optical Coherence Tomography Findings After Childhood Lensectomy

Purpose

To explore the impact of childhood lensectomy on posterior segment development.

Methods

Cross-sectional observational study at children's eye clinics at a tertiary referral center in London, UK. We included 45 children age 4 to 16 years with healthy eyes and 38 who had undergone lensectomy. We acquired posterior segment optical coherence tomography scans of both eyes. We used parametric and nonparametric tests in SPSS24 for the comparison of parameters between groups and within individuals; a P value less than 0.05 was considered significant. The main outcome measures were foveal pit depth and subfoveal choroidal thickness (CT). Secondary outcomes were inner and outer ring CT and photoreceptor layer parameters, macular and peripapillary retinal nerve fiber layer thickness.

Results

Foveal pit depth and subfoveal CT are significantly reduced in eyes that have undergone lensectomy compared with nonoperated eyes. Inner ring CT and outer ring CT are reduced. Foveal inner retinal layer thickness is increased. Mean inner retinal and outer nuclear layer thickness are not affected.

Conclusions

Childhood lensectomy is associated with a reduction in developmental foveal pit deepening and lack of developmental thickening of the posterior choroid. Mechanical and optical disruption of foveal and subfoveal choroidal development may affect structural foveal development after childhood lensectomy.

Posterior Microphthalmia, Peripheral Pigmentary Retinal Changes, Yellow Lesions, and Cleft Lip: A Case Report and Literature Review

Purpose

Posterior microphthalmia is a sporadic or inherited developmental ocular anomaly that may occur isolated or in association with multiple ocular and systemic anomalies. This report documents a case of posterior microphthalmia with atypical presentation including white dots in the posterior pole in addition to systemic anomalies including facial defect that can represent an underlying genetic mutation.

Method

Case report.

Results

A 29-year-old male with high hyperopia and history of bilateral clear lens presented with pigmentary changes and white-yellow dots in the posterior pole in both eyes. Patient had a history of cleft lip repair. A complete ocular evaluation including A/B scan and optical coherence tomography confirmed the diagnosis of posterior microphthalmia with a retinitis pigmentosa like fundus and drusen deposits in the subretinal pigment epithelium.

Conclusion

The white-yellow drusenoid deposits in the posterior pole in association with posterior microphthalmia are poorly documented in the literature. Cases of craniofacial developmental defects in association with posterior microphthalmia may represent a genetic defect.

OCT Angiography: A Technique for the Assessment of Retinal and Optic Nerve Diseases in the Pediatric Population

Optical coherence tomography angiography (OCT-A) is a novel, rapidly evolving, non-invasive imaging technique that allows images of the retinal vasculature to be obtained in a few seconds. Blood vessels of different retinal vascular plexuses and the foveal avascular zone (FAZ) can be examined without the administration of any contrast or dye. Due to these characteristics, OCT-A could be an excellent complementary test to study retinal vascularization in children. Until now, most of the studies with OCT-A have been conducted in adults and only a few have been carried out in children. In this review, we describe the principles and advantages of OCT-A over traditional imaging methods and provide a summary of the OCT-A findings in retinopathy of prematurity and other retinal and optic disc pathologies in children. In view of the promising results from studies, the advantages of a relatively rapid and non-invasive method to assess the retinal vasculature makes OCT-A a tool of which applications in the field of pediatric ophthalmology will be expanded in the near future for patient diagnosis and follow-up in every day clinical practice.

Multimodal imaging in a patient with Prader-Willi syndrome

Background

Prader-Willi syndrome (PWS) is a genetic disease caused by loss of expression of the paternally inherited copy of several genes on the long arm of chromosome 15. Ophthalmic manifestations of PWS include strabismus, amblyopia, nystagmus, hypopigmentation of the iris and choroid, diabetic retinopathy, cataract and congenital ectropion uvea. An overlap between PWS and oculocutaneous albinism (OCA) has long been recognized and attributed to deletion of OCA2 gene located in PWS critical region (PWCR).

Case report

A 30-year-old male patient with PWS presented with vision loss in his left eye. His right eye had normal visual acuity. Multimodal imaging revealed absence of a foveal depression and extremely reduced diameter of the foveal avascular zone in the right eye and an inactive type 2 macular neovascular lesion in the left eye.

Conclusions

We report a presumed association of fovea plana and choroidal neovascularization with PWS. The use of multimodal imaging revealed novel findings in a PWS patient that might enrich our current understanding of the overlap between PWS and OCA.

Absent Foveal Pit, Also Known as Fovea Plana, in a Child without Associated Ocular or Systemic Findings

The purpose of this report is to describe a case of bilateral foveal hypoplasia in the absence of other ophthalmological or systemic manifestations. We characterize the case of a 9-year-old Caucasian male who underwent full ophthalmologic examination, including functional measures of vision and structural measurements of the eye. Best corrected visual acuity was 0.50 logMAR in the right eye and 0.40 logMAR in the left eye. Ophthalmoscopy revealed a lack of foveal reflex that was further investigated. Optical coherence tomography (OCT) confirmed the absence of foveal depression (pit). OCT images demonstrated the abnormal structure of retina in a region in which we expected a fovea; these findings were decisive to determine the cause of reduced acuity in the child.

Vision and visual potential for perifoveal retinoblastoma after optical coherence tomographic-guided sequential laser photocoagulation

BACKGROUND/AIMS

To assess tumour control, vision and anatomical visual potential in eyes with perifoveal retinoblastoma treated by sequential photocoagulation from the antifoveal tumour edge inwards, avoiding treatment near the fovea. Patients were monitored for tumour control, foveal and perifoveal anatomy at each treatment session by optical coherence tomography (OCT) and treated for amblyopia when the other eye had better vision.

METHODS

Eyes with perifoveal retinoblastoma treated between 1 January 2011 and 31 May 2017 with laser therapy after chemotherapy for juxtafoveal (fovea clear of tumour but <3000 µm from tumour edge) or foveolar retinoblastoma (tumour underlying fovea) were retrospectively reviewed for tumour control without recurrence, anatomical success (foveal pit preservation and/or restoration with ≥500 µm perifoveal retina free of tumour and scar) and functional success (acceptable (>0.1 decimal) or good (>0.3 decimal) visual acuity (VA)).

RESULTS

Twenty-two eyes (14 juxtafoveal, 8 foveolar tumours) of 20 patients (19 bilateral, 1 familial and 11 females) were included. No juxtafoveal tumour had tumour recurrence, and 13/14 patients showed foveal pit preservation with ≥500 µm of perifoveal retina tumour free. Foveolar tumours had significant worse anatomical outcomes: failure to restore foveal pit or perifoveal retina (8/8, p=0.001) and tumour recurrences (5/8, p=0.001). Functional success with acceptable VA was achieved in 12/14 juxtafoveal and 5/8 foveal tumours eyes (p=0.01). Amblyopia therapy data were insufficient to evaluate impact on VA.

CONCLUSIONS

Anatomical visual potential and functional vision were better in juxtafoveal than foveolar retinoblastoma treated with foveal-sparing laser photocoagulation guided by OCT. The role of amblyopia therapy requires a prospective study.

Variable Clinical Profile of Fovea Plana in Normal Children

BACKGROUND AND OBJECTIVE

This study is designed to illustrate various clinical findings associated with fovea plana in normal children.

PATIENTS AND METHODS

A retrospective chart review of pediatric subjects with a diagnosis of fovea plana was conducted to evaluate the characteristics associated with this condition.

RESULTS

All eyes had 20/40 or better best-corrected visual acuity (BCVA). In five of six subjects (83%), there was bilateral fovea plana. Astigmatism equal or greater than +1.5 diopters was present in 45% of eyes. On spectral-domain optical coherence tomography (SD-OCT), a foveal depression was absent in 82% of eyes and the inner nuclear layer was present in the center of the fovea in all eyes analyzed.

CONCLUSION

Fovea plana is typically a bilateral disease and occurs in patients with generally good BCVA despite abnormal SD-OCT findings. However, unilateral disease may also be present. Astigmatism may be more prevalent in patients with fovea plana than initially suspected. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:251-257.].

OCT Angiographic Findings in Glucose-6-Phosphate Dehydrogenase Deficiency

Fovea plana (FP) describes the abnormal absence of the foveal pit in the retina. It is a sign that is associated with prematurity, albinism, and other ophthalmic disorders. The authors present the optical coherence tomography angiographic findings in a case of a 19-year-old male with FP and glucose-6-phosphate dehydrogenase (G6PD) deficiency. G6PD deficiency is a very common condition that typically presents with hemolytic anemia and jaundice. G6PD deficiency is also known to affect vision, but these pathologies have been less well-characterized. To the authors' knowledge, this is the first report of G6PD deficiency in FP. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:664-667.].

Leigh-like neuroimaging features associated with new biallelic mutations in OPA1

Behr syndrome is characterized by the association of early onset optic atrophy, cerebellar ataxia, pyramidal signs, peripheral neuropathy and mental retardation. Recently, some cases were reported to be caused by biallelic mutations in OPA1. We describe an 11-year-old girl (Pt1) and a 7-year-old boy (Pt2) with cognitive delay, ataxic gait and clinical signs suggestive of a peripheral neuropathy, with onset in early infancy. In Pt1 ocular fundus examination revealed optic disk pallor whereas Pt2 exhibited severe optic atrophy. In both children neuroimaging detected a progressive cerebellar involvement accompanied by basal ganglia hyperintensities and pathological peak levels of lactate. In both patients, muscle biopsy showed diffuse reduction of cytochrome c oxidase stain, some atrophic fibers and type II fiber grouping. Using a targeted resequencing panel in next generation sequencing, we identified the homozygous c.1180G>A/p.Ala394Thr mutation in Pt1 and the c.2779-2A>C mutation in compound heterozygosity with the c.2809C>T/p.Arg937Cys mutation in Pt2. All variants were novel and segregated in the healthy parents. Expression of OPA1 protein was significantly reduced in muscle tissues of both patients by Western blotting. We also observed in patients' fibroblasts a higher proportion of fragmented and intermediate mitochondria upon galactose treatment compared to controls, as already seen in other patients harboring mutations in OPA1. The presence of Leigh-like neuroimaging features is a novel finding in Behr syndrome and further adds to the complex genotype-phenotype correlations in OPA1-associated disorders.

Optical Coherence Tomography Angiography in Fovea Plana

Fovea plana is characterized by the anatomical absence of the foveal pit in eyes with normal visual function. The authors have analyzed three cases of idiopathic fovea plana with optical coherence tomography angiography (OCTA). As previously reported, the authors found the absence of a foveal avascular zone in all cases with OCTA; however, a preserved fusion of both the superficial and the deep capillary plexuses was found around the foveal center. This novel observation cannot be detected with conventional dye-based angiography, in which the deep capillary plexus is not visualized. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:670-673.].

Optical coherence tomography angiography of foveal hypoplasia

AIMS

To discuss foveal development in the context of detailed retinal vasculature imaging in foveal hypoplasia using optical coherence tomography angiography.

METHODS

In this case series, the optical coherence tomography angiography results of four patients with idiopathic foveal hypoplasia and two patients with foveal hypoplasia secondary to oculocutaneous albinism are presented.

RESULTS

Cases with intact visual acuity demonstrated lower grades of foveal hypoplasia on optical coherence tomography, while those with poor vision demonstrated high grades of foveal hypoplasia. The superficial retinal capillary plexus was intact in the foveal area in all cases, with no demonstrable foveal avascular zone. The deep retinal capillary plexus was absent to variable degrees in most cases, but was most persistent in those cases with reduced vision.

CONCLUSIONS

The superficial retinal capillary plexus is present in cases with foveal hypoplasia, while the deep retinal capillary plexus is absent to varying degrees. Our findings support the hypothesis that an intact foveal avascular zone of the deep capillary plexus allows for outer retinal photoreceptor specialisation to occur unimpeded, resulting in preserved visual acuity, while this process may be inhibited by an absent deep capillary foveal avascular zone with resultant poor vision.