Optical Coherence Tomography Normative Peripapillary Retinal Nerve Fiber Layer and Macular Data in Children 0-5 Years of Age

Biphasic change in retinal nerve fibre layer thickness from 30 to 60 weeks postmenstrual age in preterm infants

BACKGROUND/AIMS

The optic nerve development during the critical postnatal weeks of preterm infants is unclear. We aimed to investigate the change of retinal nerve fibre layer (RNFL) in preterm infants.

METHODS

We used an investigational handheld optical coherence tomography (OCT) system to serially image awake preterm infants between 30 and 60 weeks postmenstrual age (PMA) at the bedside. We assessed RNFL thickness in the papillomacular bundle and nasal macular ganglion cell layer+inner plexiform layer (GCL+IPL) thickness. We applied a segmented mixed model to analyse the change in the thickness of RNFL and GCL+IPL as a function of PMA.

RESULTS

From 631 OCT imaging sessions of 101 infants (201 eyes), RNFL thickness followed a biphasic model between 30 and 60 weeks, with an estimated transition at 37.8 weeks PMA (95% CI: 37.0 to 38.6). RNFL thickness increased at 1.8 μm/week (95% CI: 1.6 to 2.1) before 37.8 weeks and decreased at -0.3 μm/week (95% CI: -0.5 to -0.2) afterwards. GCL+IPL thickness followed a similar biphasic model, in which the thickness increased at 2.9 μm/week (95% CI: 2.5 to 3.2) before 39.5 weeks PMA (95% CI: 38.8 to 40.1) and then decreased at -0.8 μm/week (95% CI: -0.9 to -0.6).

CONCLUSION

We demonstrate the feasibility of monitoring RNFL and GCL+IPL thickness from OCT during the postnatal weeks of preterm infants. Thicknesses follow a biphasic model with a transition age at 37.8 and 39.5 weeks PMA, respectively. These findings may shed light on optic nerve development in preterm infants and assist future study designs.

Determining relative thickness of inner retinal layers on single-line foveal optical coherence tomography (OCT) in healthy pediatric eyes-normative data for handheld OCT

BACKGROUND

Handheld optical coherence tomography (HH-OCT) lacks integrated segmentation/analysis software. Optic neuropathies cause ganglion cell layer (GCL) thinning, with normal to thickened inner nuclear layer (INL), suggesting the potential value of estimating the GCL/INL ratio on single-line foveal HH-OCT scans. This study determines this ratio in macular scans from healthy eyes of young children using HH-OCT and overhead-mounted OCT.

METHODS

Macular OCT scans were obtained using either HH-OCT or overhead-mounted Spectralis FLEX-OCT in children ages 0-5 years undergoing clinically indicated anesthesia/sedation. Exclusion criteria included gestational age <37 weeks, neurologic disease, amblyopia, ocular disease, or large refractive error (spherical equivalent beyond -3.00 D to +8.00 D). For HH-OCT, the GCL and INL were manually measured in pixels from single-line macular scans at the thickest point nasal and temporal to the fovea. For FLEX-OCT images, measurements were aided by automated software.

RESULTS

HH-OCT was obtained on 38 eyes (38 children, mean age 2.4 ± 1.8 years) and FLEX-OCT on 56 eyes (56 children, mean age 2.3 ± 1.5 years). Mean nasal GCL/INL was 1.24 ± 0.18 (min/max = 0.92/1.75) for HH-OCT and 1.29 ± 0.18 (min/max = 0.96/1.66) for FLEX-OCT (P = 0.11). Mean temporal GCL/INL was 1.22 ± 0.24 (min/max = 0.66/1.70) for HH-OCT and 1.19 ± 0.16 (min/max = 0.86/1.47) for FLEX-OCT (P = 0.47).

CONCLUSIONS

Mean normative GCL/INL ratios were approximately 1.2 at the thickest macular areas both nasal and temporal to the fovea, with either HH-OCT or FLEX-OCT in young children's eyes. These values may prove useful when HH-OCT is used to assess optic neuropathies, in which the GCL/INL ratio is expected to be decreased.

Preterm infant retinal OCT markers of perinatal health and retinopathy of prematurity

The increasing survival of preterm infants has led to the importance of improving long-term outcomes associated with preterm birth. Antenatal and perinatal insults not only impact mortality, but also long-term disability. While in the intensive care nursery, preterm infants are also exposed to various stressors that lead to long-term cognitive deficits. It is therefore critical to identify early, low-stress, non-invasive biomarkers for preterm infant health. Optical coherence tomography (OCT) is a powerful imaging modality that has recently been adapted to the infant population and provides noninvasive, high-resolution, cross-sectional imaging of the infant eye at the bedside with low stress relative to conventional examination. In this review we delve into discussing the associations between preterm systemic health factors and OCT-based retinal findings and their potential contribution to the development of non-invasive biomarkers for infant health and for retinopathy of prematurity (ROP).

An Isolated Case of Unilateral Macro-Ophthalmia With Resultant Anisometropic Amblyopia in Neurofibromatosis 1

The most common causes of vision loss in neurofibromatosis 1 (NF1) patients are sequelae from tumors such as optic pathway glioma, plexiform neurofibroma, or secondary glaucoma. Here we report the case of a six-year-old female with anisometropic amblyopia resulting from an isolated unilateral macro-ophthalmia with a known history of NF1. Our patient progressed to light perception vision in the left eye due to a non-neoplastic cause associated with NF1 with at least two years of documented unilateral macro-ophthalmia without any ophthalmology referral or evaluation. This case aims to highlight the importance of early and deliberate ophthalmologic examination in all patients with neurofibromatosis 1 to assess for appropriate visual development and early intervention.

Retinal Nerve Fiber Layer Imaging with Two Different Spectral Domain Optical Coherence Tomographs: Normative Data for Romanian Children

The purpose of this study is to analyze and compare pediatric normative data for the retinal nerve fiber layer of Romanian children using two different spectral domain optical coherence tomographs. Due to different scanning speeds and axial and transverse resolution, the results of the measurements of scans cannot be transposed. A total of 140 healthy children aged 4 to 18 were enrolled in the study. Overall, 140 eyes were scanned with a Spectralis SD-OCT (Heidelberg Technology), and the other 140 eyes were imaged with a Copernicus REVO SOCT (Optopol Technology (Zawiercie, Poland)). The mean global RNFL thickness and average RNFL thickness for the four quadrants were measured and compared. The average peripapillary RNFL thickness measured with the Spectralis was 104.03 ± 11.42 (range 81 to 126 µm), while the one measured with the Revo 80 was 127.05 ± 15.6 (range 111.43-158.28). The RNFL thickness measurements taken with the Spectralis in the superior, inferior, nasal, and temporal quadrants were 132 ±19.1, 133.5 ± 21.77, 74 ± 16.48, and 73 ± 11.95 µm, respectively, while those taken with the Revo 80 were 144.44 ± 9.25, 144.86 ±23.12, 96.49 ± 19.41, and 77 ± 11.4 µm, respectively. Multivariate analysis showed that the average RNFL thickness was not influenced by gender or eye laterality and was negatively correlated with age when we used the Spectralis device. This study provides normative data for SD-OCT peripapillary RNFL in healthy Romanian children for two different tomographs. These data help the clinician evaluate and interpret the results of optical coherence tomography for a child, taking into consideration all the technical and individual parameters.

Normative data for macular and retinal nerve fibre layer thickness in healthy German children and adolescents using optical coherence tomography

PURPOSE

To establish normative data for macular thickness, macular volume and peripapillary retinal nerve fibre layer (RNFL) thickness using Spectralis® spectral-domain optical coherence tomography (SD-OCT) in healthy German children and adolescents and investigate influencing factors.

METHODS

The cross-sectional study included the right eye of 695 children with at least one complete retinal OCT scan. As part of the LIFE Child study, the children underwent an ophthalmological examination including axial length (AL), spherical equivalent (SE) and OCT measurements. Various questionnaires were answered by the children or their parents to identify media use or outdoor time. Multiple linear regression models were used to investigate the potential influencing factors.

RESULTS

A total of 342 boys and 353 girls with an average age (SD) of 12.91 (3.29) years participated. The mean AL (SD) was 23.20 (0.86) mm. The mean macular thickness (SD) was 320.53 (12.29) μm and the mean RNFL thickness (SD) was 102.88 (8.79) μm. Statistical analysis revealed a significant correlation between average macular thickness and age (p < 0.001, β = 0.77) as well as AL (p < 0.001, β = -4.06). In addition, boys had thicker maculae (p < 0.001, β = 5.36). The RNFL thickness showed no significant correlation with children's age (p > 0.05), but with AL (p = 0.002, β = -2.15), birth weight (p = 0.02, β = 0.003) and a gender-specific effect of the body mass index standard deviation score for male participants (p = 0.02, β = 1.93).

CONCLUSION

This study provides normative data and correlations between macular and RNFL thickness in healthy German children. Especially age, gender and AL must be taken into account when evaluating quantitative OCT measurements to classify them as normal.

Retinal injury identified by overhead-mounted optical coherence tomography in two young children with infantile-onset glaucoma

PURPOSE

To report and characterize unexpected retinal findings identified by imaging with overhead-mounted optical coherence tomography (OCT) in 2 young children with infantile-onset glaucoma.

METHODS

Children with glaucoma were imaged during clinically indicated examinations under anesthesia using overhead-mounted HRA+OCT Spectralis with Flex module (Flex-OCT, Heidelberg, Germany) from February 2017 through February 2022. Imagers prioritized scans of the peripapillary retinal nerve fiber layer (pRNFL), optic nerve head, and macula. Children imaged before age 2 years with images adequate for evaluation were included. Age at glaucoma diagnosis, glaucoma type, highest intraocular pressure (IOP), corneal diameter (CD), and axial length (AL) were recorded.

RESULTS

A total of 41 children (71 eyes with glaucoma) were imaged before age 2 years. Macular imaging identified both inner and outer retinal thinning in 3 eyes of 2 young children (both eyes of a child with newborn primary congenital glaucoma (PCG) and 1 eye of a child with glaucoma following cataract surgery), which remained stable over time. These findings were present in 2 of 41 children (4.9%) and 3 of 71 eyes (4.2%) imaged with Flex-OCT. Neither highest IOP, CD, nor AL at imaging differentiated the 3 eyes with retinal changes from the larger group.

CONCLUSIONS

Three eyes of 2 young children with refractory glaucoma of different etiologies and highly elevated IOP demonstrated areas of inner and outer retinal thinning, consistent with retinal injury from probable prior macular ischemia. Unexpected retinal pathology identified on Flex-OCT imaging in infantile-onset glaucomas highlights the need for continued study of the pathophysiology of this disease.

Long-term effects of early/late-onset visual deprivation on macular and retinal nerve fibers layer structure: A pilot study

BACKGROUND/AIMS

Tomographic analysis of macular and peripapillary retinal nerve fibers layer (RNFL) thickness in patients with history of congenital (CC) and developmental cataract (DC).

METHODS

Analysis of macular and RNFL thickness using a spectral-domain optical coherence tomography was performed. Retinal layers thickness was measured using the internal segmentation software. Measurements of affected (unilateral and bilateral), contralateral eyes and control eyes were compared.

RESULTS

Patients with history of CC or DC (n = 13 and 11 respectively) and 35 healthy control subjects were enrolled. Thicker inner and outer nuclear layers (INL, ONL) and thicker ONL were found when CC and DC group when compared to controls respectively. Bilateral CC showed the most relevant differences. Slight thickening of CC inner retinal layers were found when compared to DC. Increased superonasal RNFL thickness was found in CC group when compared to DC and controls. Thickening of RNFL of contralateral unaffected eyes of unilateral CC were found when compared to controls.

CONCLUSION

Significant macular and RNFL thickness changes between CC, DC patients and controls that partially involve also contralateral unaffected eyes of unilateral congenital cataract were found. CC and DC groups show significant differences only in inner retinal layers thickness. Our data suggest that early visual deprivation may influence retinal arrangements occurring during development involving predominantly the outer nuclear layer and para/perifoveal inner retinal layers, and confirm that early treatment of CC allow to achieve better long-term visual outcome. Moreover functional and structural data support the hypothesis that unilateral amblyopia is not exclusively an unilateral issue.

Normative Data of Macular Thickness Using Spectral Domain Optical Coherence Tomography for Healthy Jordanian Children

Purpose

To report normative values of macular thickness and volume by spectral-domain optical coherence tomography (SD-OCT) in the eyes of healthy Jordanian children aged 6–16 years and assess the correlation of macular parameters with age, sex, and refractive error.

Patients and Methods

This observational study included 144 eyes of 144 healthy children. All children underwent comprehensive ocular examination and cycloplegic refraction. Average macular thickness, macular volume, central subfield thickness (CST), and macular thickness for all the Early Treatment Diabetic Retinopathy Study (ETDRS) quadrants were obtained using Primus SD-OCT (Carl Zeiss Meditec).

Results

The study group consisted of 68 boys and 76 girls with a mean age (SD) of 10.8 (3.0) years. The mean (SD) spherical equivalent refraction (SER) was 0.56 (1.73) diopters (range: −4.75 to 4.75). The mean of macular average thickness was 277.2±12.5 μm, and the mean of the central subfield thickness was 246.7±16.8 μm. In multivariate analysis, all macular parameters except the central subfield thickness (CST) correlated positively with the SER. Boys had significantly higher CST than girls (p=0.008). None of the macular parameters were correlated with age.

Conclusion

Normative data of macular thickness for healthy Jordanian children were established for sex and age groups using SD-OCT.

Intra-Operative Mounted Optical Coherence Tomography Findings Following Reversal of Optic Nerve Head Cupping in Childhood Glaucoma

PURPOSE

To examine the structural changes occurring in the optic nerve head (ONH) and macula in infants with childhood glaucoma and clinically observed ONH cupping reversal following intraocular pressure (IOP)-reducing glaucoma surgery, as captured by intra-operative spectral-domain optical coherence tomography (SD-OCT).

DESIGN

Retrospective observational case series from an ongoing prospective cohort study.

METHODS

Included were 18 eyes of 14 patients with childhood glaucoma. All eyes had SD-OCT imaging pre- and post-glaucoma intervention and clinically identified ONH cupping reversal. Patients with poor quality images or persistent optic nerve swelling following IOP reduction were excluded. Outcome measurements included IOP, cup-to-disc ratio, axial length and SD-OCT measurements of the peripapillary retinal nerve fiber layer (pRNFL), transverse horizontal diameter of Bruch membrane opening (BMO-D), cup depth, and macula.

RESULTS

Mean age at surgery was 1.14±0.93 years and mean interval between pre- and post-operative imaging was 127 days (range 35-595). Following intervention, mean IOP reduction was 45%, accompanied by significant reductions in the cup-to-disc ratio (0.30±0.12, p<0.001), axial length (0.43±0.28mm, p<0.001) and cup depth (46%, p<0.001). Mean global pRNFL thickness pre- vs. post-treatment was 93.1±14.7µm vs. 93.1±17.1µm, respectively, p=1.0. There was no significant difference in pre- and post-treatment global or sectoral pRNFL, 3mm macular total and segmented retinal layer volumes, or the BMO-D.

CONCLUSIONS

Clinical ONH cupping reversal after IOP-lowering surgery was associated with axial length reduction and decrease in cup depth, but no significant change in the pRNFL or macular volume measures. ONH cupping reversal likely marks stabilization but any pre-intervention ONH damage persists.

Optical coherence tomography in the diagnosis and monitoring of congenital and juvenile glaucoma

Optical coherence tomography (OCT) in everyday routine practice is the method of choice for the instrumental diagnosis of glaucoma in adults. As a non-invasive and safe method of visualizing structural changes in the retina and the optic nerve, the method is of particular value in pediatric practice. At the same time, OCT diagnostics in children is associated with certain difficulties, both during the study and when interpreting the scan results.

This review summarizes the data from the literature and our own research in the diagnosis and monitoring of congenital and juvenile glaucoma from the standpoint of our own long-term clinical experience in using optical coherence tomography. We consider the physiological changes of the retina and optic nerve, attention is focused on the need to create a pediatric regulatory database of retinal thickness, the factors that determine the normal range of the data obtained and allow distinguishing physiological processes from pathological ones are identified. Clinical cases confirming the value of OCT in combined pathology are presented as examples.

The use of OCT to detect signs of intracranial hypertension in patients with sagittal suture synostosis: Reference values and correlations

PURPOSE

To obtain pediatric normative reference values and determine whether optical coherence tomography (OCT) corresponds better with clinical signs of intracranial hypertension (ICH) compared to the traditional screening method fundoscopy in a large cohort of one type of single suture craniosynostosis.

METHODS

Control subjects without optic nerve diseases and isolated sagittal synostosis patients aged 3-10 years who underwent fundoscopy and OCT were included in this prospective cohort study. Normative reference values were obtained through bootstrap analysis. Main outcome was the association between peripapillary total retinal thickness (TRT) and total retinal volume (TRV) and appearance on fundoscopy. Signs and symptoms suggestive of ICH, including skull growth arrest, fingerprinting, and headache, were scored.

RESULTS

Sixty-four healthy controls and 93 isolated sagittal synostosis patients were included. Normative cut-off values for mean TRT are < 256 μm and > 504 μm and for mean TRV < 0.21 mm³ and > 0.39 mm³. TRT was increased in 16 (17%) and TRV in 15 (16%) of 93 patients, compared to only 4 patients with papilledema on fundoscopy (4%). Both parameters were associated with papilledema on fundoscopy (OR = 16.7, p = 0.02, and OR = 18.2, p = 0.01). Skull growth arrest was significantly associated with abnormal OCT parameters (OR = 13.65, p < 0.01).

CONCLUSIONS

The established cut-off points can be applied to screen for ICH in pediatrics. The present study detected abnormalities with OCT more frequent than with fundoscopy, which were associated with skull growth arrest. Therefore, a combination of OCT, fundoscopy, and skull growth arrest can improve clinical decision-making in craniosynostosis.

Changes of Peripapillary Retinal Nerve Fiber Layer in Childhood Glaucoma: A Systematic Review and Meta-Analysis

Objectives: Retinal nerve fiber layer (RNFL) thickness has been detected by numerous studies about alterations and abnormalities in childhood glaucoma, but these studies have yielded inconsistent results about the RNFL thinning region. The investigation of characteristics of RNFL in pediatric patients would contribute to the deep understanding of the neuropathic mechanisms of childhood glaucoma. Thus, the degree of thinning in different quadrants deserves further discussion and exploration. Method: A systematic literature search was conducted using the Cochrane Central Register of Controlled Trials, Medline, Embase, and PubMed databases to identify clinical studies published from inception to April 1, 2021. Results: Ten studies were included in this review with a total of 311 children with glaucoma and 444 in nonglaucomatous controls. The results revealed that average peripapillary RNFL (pRNFL) thickness was attenuated in pediatric patients with glaucoma [weighted mean difference (WMD) = -20.75; 95% CI -27.49 to -14.01; p < 0.00001]. Additionally, pRNFL thickness in eight quadrants (superior, inferior, temporal, nasal, superotemporal, inferotemporal, superonasal, and inferonasal) had different levels of reduction in the pediatric group of glaucoma. Conclusion: This study indicates that eight regions of RNFL thickness show various degrees of thinning in childhood glaucoma. However, caution is required in the interpretation of results due to marked heterogeneity. Future studies, especially larger samples and multicenter, need to confirm our results.

Normative data for optical coherence tomography in children: a systematic review

The purpose of this study is to systematically review the reported data of normal optical coherence tomography (OCT) results in the paediatric population. A systematic literature search was performed using the PubMed, Embase, and Web of Science databases, using the keywords "optical coherence tomography"; "normative data" or "healthy eyes"; "children" or "paediatric population". Studies with at least 50 participants were included, irrespective of the OCT equipment employed. We excluded the OCT angiography studies or the studies investigating the choroidal thickness. Seventy-four studies were included in the final analysis and information on study design, number of participants, demographic characteristics, type of OCT equipment, OCT parameters and results was collected. Due to the high variability of OCT instruments and parameters used, a meta-analysis was not feasible. We report the normative values for the peripapillary retinal nerve fibre layer thickness and the macular retinal thickness for each ETDRS quadrant, as provided by the studies included in the present analysis. We also report the influence of ethnicity, age, gender, eye laterality, ISNT rule, spherical equivalent, and axial length on OCT results.

Overhead Mounted Optical Coherence Tomography in Childhood Glaucoma Evaluation

PRéCIS:: Overhead mounted spectral-domain optical coherence tomography (OCT) enables high-quality imaging of the optic nerve and macula in childhood glaucoma, and is particularly useful when standard tabletop OCT has failed or is not possible.

PURPOSE

Tabletop OCT, integral to adult glaucoma management, can be limited in childhood glaucoma patients because of young age, poor cooperation, and/or technical challenges. To address these imaging difficulties, we determined the feasibility and quality of an overhead mounted unit in childhood glaucoma. Secondary aims included evaluation of peripapillary retinal nerve fiber layer (pRNFL), parafoveal total retinal thickness, and parafoveal ganglion cell complex (GCC) thickness.

MATERIALS AND METHODS

Children and adults with a diagnosis of childhood glaucoma were imaged with an overhead mounted spectral-domain OCT as part of a prospective cross-sectional study. Participants had poor quality or unobtainable tabletop OCT and were scheduled for an examination under anesthesia and/or surgery as part of standard care.

RESULTS

A total of 88 affected eyes in 60 of 65 (92.3%) enrolled patients (mean age, 5.9±5.9 y; range, 0.2 to 24.5) were successfully imaged. The mean image quality for analyzed scans was 22.9±6.0 dB (n=236 images). Mean values for pRNFL (80.5±31.0 µm; n=86), parafoveal total retinal thickness (301.10±39.9 µm; n=79), and parafoveal GCC thickness (96.0±21.6 µm; n=74) were calculated.

CONCLUSIONS

Overhead mounted OCT allowed high-quality image acquisition and analysis in childhood glaucoma patients unable to be imaged with the tabletop counterpart, presenting an opportunity for improved clinical management and study of childhood glaucoma-related pathophysiology. pRNFL, parafoveal total retinal thickness, and parafoveal GCC thickness were decreased for affected eyes of children under 6 years of age compared with age-matched controls from a companion normative study.

Spectral Domain - Optical Coherence Tomography findings in Triple-A Syndrome - A case series from Pakistan

Triple A Syndrome is an autosomal recessive entity involving multiple systems usually characterized by adrenal insufficiency, alacrimia and achalasia. The disease features include variable degrees of neurological and neuro-ophthalmic manifestations. Protein ALADIN encoded by the AAAS gene is found to be defective in Triple A Syndrome. Here we discuss a case series of five patients diagnosed as Triple A Syndrome. Clinically there was variable degree of optic atrophy in all the cases, which was further confirmed with spectral domain Optical Coherence Tomography The aim of this study was to publish the OCT based ONFL graphs of these unique cases, so that being an ophthalmologist we can take a multidisciplinary approach and decisions accordingly.

Thicknesses of Macular Inner Retinal Layers in Children with Anisometropic Amblyopia

Objective

To investigate the thicknesses of macular inner retinal layers in children with anisometropic amblyopia using spectral domain optical coherence tomography (SD-OCT).

Methods

Thirty-seven children with anisometropic amblyopia and fifty-seven children with normal vision were recruited in the study. Both eyes of children with anisometropic amblyopia and the right eyes of normal controls underwent scanning with the Spectralis OCT. The segmentation of retinal layers was performed automatically to measure individual inner retinal layers in the five sectors of the macular. An independent sample t-test was applied to compare the mean layer thicknesses of anisometropic eyes and fellow eyes with those of control eyes.

Results

There was no significant difference in the total macular thickness between amblyopic and control eyes. However, in the peripheral macular area, three of the four quadrants of both the ganglion cell layer (GCL) and the inner plexiform layer (IPL) thicknesses were significantly reduced in amblyopic eyes compared to control eyes. Moreover, two of the four quadrants of the GCL thickness and three of the four quadrants of the IPL thickness in the peripheral macular area were significantly reduced in fellow eyes than in control eyes.

Conclusion

The SD-OCT data revealed differences in the thicknesses of some macular inner retinal layers in both eyes of children with anisometropic amblyopia compared with those with emmetropia, indicating that structural changes might exist in the retina of children with amblyopia.

Optical coherence tomography imaging of the pediatric retina

Optical coherence tomography is an increasingly important part of the retinal specialist's and general ophthalmologist's toolkit for diagnosing and managing retinal disease. This review summarizes the unique considerations and available imaging systems with which pediatric ophthalmologists should be familiar when attempting optical coherence tomography in children. Normal developmental changes in foveal and extrafoveal structure and the need for an established pediatric normative database of retinal thicknesses are reviewed. Finally, applications of optical coherence tomography imaging to selected representative pediatric retinal diseases are introduced as examples of how optical coherence tomography in children is furthering the diagnosis and management of vision-threatening retinal diseases.

Determination of Referential Rates for Optical Coherence Tomography and Optical Coherence Tomography Angiography Flow Deficits in the Macular Choriocapillaris in Ophthalmologically Healthy Children

Background and Objectives: Despite the growing number of new research publications, normative references for children's optical coherence tomography (OCT) parameters are still not completed. We chose to explore this topic because of the lack of normative parameters that is due to an improvement in different technologies and instruments. Our aim was to determine referential rates of retinal nerve fiber layer (RNFL) thickness and flow deficits (FD%) in the macular choriocapillaris (CC) in normal eyes of ophthalmologically healthy children. Materials and Methods: Ophthalmologically healthy 8- to 14-year-old individuals participated (n = 75) in this study. OCT images were taken using an swept-source-OCT (SS-OCT) instrument (DRI-OCT Triton, Topcon, Tokyo, Japan). The early treatment diabetic retinopathy study (EDTRS) grid (6 × 6 mm) divided the RNFL into the thickness maps. The FD% values of the CC were calculated on the 3 × 3-mm scans in a 1-mm circle (C1), 1.5-mm rim (R1.5), and the entire 2.5-mm circle (C2.5), and on the 6 x 6-mm scans in a 1-mm circle (C1), 1.5-mm rim (R1.5), the entire 2.5-mm circle (C2.5), 2.5-mm rim (R2.5), and 5-mm circle (C5). Results: Both scan quantifications of FD% in the C1, C2.5, and R1.5 sectors were similar, but the 6 × 6-mm scan measurements were statistically significantly smaller than the 3 × 3-mm ones. Significant moderate correlations were found between axial length (AxL) and FD% in the 6 × 6-mm scans, namely C1 (r = -0.347, p = 0.002), C2.5 (r = -0.337, p = 0.003), R1.5 (r = -0.328, p = 0.004), R2.5 (r = -0.306, p = 0.008), and C5 (r = -0.314, p = 0.006). Conclusions: The thinnest RNFL layers were on the temporal and nasal sides. FD% values in the C1, C2.5, and R1.5 sectors were similar between the 3 × 3-mm and 6 × 6-mm scans. The negative moderate correlations between AxL and FD% were found in all C1, C2.5, C5, R1.5, and R2.5 sectors of the 6 × 6-mm scans. Further prospective studies are needed to determine more accurate normative references for children's OCT parameters.