Evaluation of the nerve fiber layer and macula in the eyes of healthy children using spectral-domain optical coherence tomography

Retinal nerve fibre layer and ganglion cell complex thickness in patients with keratoconus

Background: Keratoconus, a corneal ectasia, is associated with corneal thinning and altered optical media. Consequently, assessment of the visual field, optic nerve head and intraocular pressure measurements may be challenging in patients with keratoconus. Few studies have investigated posterior segment variables including the retinal nerve fibre layer (RNFL) and ganglion cell complex (GCC) thickness in patients with keratoconus.Aim: To investigate RNFL and GCC thickness in patients with keratoconus.Methods: A comparative quantitative research design was used. The sample consisted of 56 participants (28 with mild, moderate or severe keratoconus, and 28 controls) who accessed the optometry clinic at the University of KwaZulu-Natal. There was an equal distribution of male (n = 14) and female (n = 14) participants in the keratoconus and control groups. Most participants were black (n = 34) or Indian (n = 18). Corneal power and refractive error were assessed with the Oculus Keratograph and subjective refraction respectively. The iVue-100 optical coherence topography device was used to measure RNFL and GCC thickness. Data were analysed by descriptive and inferential statistics.Results: The mean global RNFL thickness was slightly higher in the control group than the keratoconus group for the right (106 µm vs. 99 µm) and left (103 µm vs. 98 µm) eyes but these differences were not significant (p ≥ 0.057). For all RNFL quadrants, slightly lower mean RNFL measurements were found in the keratoconus group. The mean GCC thicknesses were marginally higher (3 µm – 6 µm) in the control group.Conclusion: The RNFL and GCC thickness differences between patients with keratoconus and controls are not clinically significant. Therefore, abnormally reduced RNFL and GCC thickness measurements in patients with keratoconus warrant further investigation for other pathologies specifically glaucoma.

Interocular symmetry of retinal nerve fiber layer and optic nerve head parameters measured by Cirrus high-definition optical coherence tomography in a normal pediatric population

Purpose:

To determine interocular differences in the retinal nerve fiber layer (RNFL) and optic nerve head (ONH) parameters in a pediatric population using Cirrus high-definition optical coherence tomography (HD-OCT).

Methods:

Seventy normal Indian children aged 5–17 years presenting to the Pediatric Clinic were included in this observational cross-sectional study. All subjects underwent a comprehensive ophthalmologic examination and an evaluation of the RNFL and ONH by Cirrus HD-OCT. Differences between the right and left eyes were calculated and values were compared by means of a paired t-test. Subjects were also divided into two groups based on age (under or over 10 years of age). Interocular differences in RNFL and ONH parameters together with sex and age variations for these differences were determined.

Results:

The mean age of studied pediatric population was 11.83 ± 3.3 years (range 5–17). Average RNFL thickness was 94.46 ± 8.7 μm (± SD) (range 77–111). Differences in the average RNFL between right and left eyes were not statistically significant (P = 0.060). Superior quadrant RNFL was thicker in the left eye and temporal quadrant was thicker in the right eye. Among ONH parameters, there were no statistically significant differences in any parameters, except vertical cup-disc (CD) ratio which was significant (P = 0.007). The 2.5%–97.5% limits of asymmetry were 9 μm for average RNFL, 0.14 for average CD ratio, and 0.22 for vertical CD ratio. Mean interocular RNFL thickness differences in superior, superior nasal, and temporal superior quadrants were 10.61 (P < 0.001), 12.57 (P < 0.001), and 4.46 (P = 0.002) μm, respectively. Interocular nerve fiber layer thickness differences were not significantly correlated with sex, while only significant differences with age were observed in 12 clock hour sector analysis, mainly in nasal inferior and inferior quadrant.

Conclusions:

We report the degree of interocular symmetry of RNFL and ONH parameters measured by Cirrus HD-OCT in a healthy pediatric population. The normal interocular RNFL asymmetry should not exceed 9 μm and vertical CD ratio beyond 0.22 should be considered for further investigations. The physiologic asymmetry provided by this study may assist in identifying changes in RNFL thickness and ONH parameters in pediatric glaucoma and ONH disorders.

Peripapillary retinal nerve fiber layer thickness in patients with iron deficiency anemia

Purpose:

To evaluate the effect of iron deficiency anemia (IDA) on peripapillary retinal nerve fiber layer (RNFL) thickness with optical coherence tomography (OCT).

Materials and Methods:

102 female patients who had IDA (hemoglobin <12 g/dl, serum transferrin saturation <15%, serum iron <50 μg/dl, and serum ferritin <15 μg/dl) were enrolled in the study. Optic disc and RNFL parameters obtained by Cirrus high-definition OCT 4000 were compared with those of 49 age and sex-matched nonanemic individuals. The time between blood analysis and OCT measurements was 3.14 ± 5.6 (range, 0–28) days in the anemia group, and 3.5 ± 6.7 (range, 0–27) days in the control group (P = 0.76).

Results:

Average ages of 102 patients and 49 control subjects were 35.76 ± 10.112 (range, 18–66) years, and 36.08 ± 8.416 (range, 19–57) years (P = 0.850), respectively. The average RNFL thickness was 94.67 ± 9.380 in the anemia group, and 100.22 ± 9.12 in the control group (P = 0.001). Temporal, nasal, and lower quadrant average RNFL thicknesses of IDA group were thinner than the control group (P = 0.001, P = 0.013, P = 0.008). Upper quadrant RNFL thicknesses in IDA and control groups were similar. Correlation analysis revealed positive correlation between mean RNFL thickness and hemoglobin (r = 0.273), iron (r = 0.177), ferritin (r = 0.163), and transferrin saturations (r = 0.185), while a negative correlation was found between total iron binding capacity (r = −0.199) and mean RNFL thickness.

Conclusions:

Peripapillary RNFL thickness measured by OCT is thinner in adult female patients with IDA. It may have a significant influence on the management of many disorders such as glaucoma and neuro-ophthalmological diseases.

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.

Longitudinal changes in macular retinal layer thickness in pediatric populations: Myopic vs non-myopic eyes

Knowledge of the normal in vivo thickness of the retina, and its individual layers in pediatric populations is important for diagnosing and monitoring retinal disorders, and for understanding the eye’s normal development and the impact of eye growth and refractive error such as myopia (short-sightedness) upon retinal morphology. In this prospective, observational longitudinal study, total retinal thickness (and individual retinal layer thickness) and the changes in retinal morphology occurring over an 18-month period were examined in 101 children with a range of refractive errors. In childhood, the presence of myopia was associated with subtle but statistically significant (p<0.05) changes in the topographical thickness distribution of macular retinal thickness (and retinal layer thickness), characterised by a thinning of the parafoveal retina (and parafoveal or perifoveal thinning in most outer and inner retinal layers). The parafoveal retina was on average 6 μm thinner in myopic children. However, over 18 months, longitudinal changes in retinal thickness and individual layers were of small magnitude (average changes of less than 2 μm over 18 months), indicative of a high degree of stability in retinal morphology in healthy adolescent eyes, despite significant eye growth over this same period of time. This provides the first detailed longitudinal assessment of macula retinal layer morphology in adolescence, and delivers new normative data on expected changes in retinal structure over time and associated with myopia during this period of childhood development.

Are there any changes in posterior ocular structure parameters in pediatric migraine patients?

PURPOSE

To evaluate the thickness of the peripapillary retinal nerve fiber layer (RNFL), total macula, macular ganglion cell layer (GCL), inner plexiform layer (IPL), and choroid in pediatric migraine patients and compare the values with healthy subjects.

METHODS

This observational and cross-sectional study included 40 patients in the migraine group and 40 healthy control subjects. The thickness of the peripapillary RNFL, total macula, GCL, and IPL was analyzed with spectral-domain optic coherence tomography, while choroidal thickness was analyzed with the enhanced depth imaging protocol. All measurements of the migraine patients were taken in the attack-free period. Right eye selected per subject was included in the study.

RESULTS

There was no significant difference between the 2 groups in age or sex (p>0.05). The peripapillary RNFL thickness was not significantly different between the 2 groups in any quadrant. The total macula, GCL, and IPL thickness were also not significantly different in the 9 separate macular areas defined on the basis of the Early Treatment Diabetic Retinopathy Study (p>0.05). The choroidal thickness at 5 different measurement points was not statistically significantly different between migraine patients during the attack-free period and the healthy subjects (p>0.05).

CONCLUSIONS

Childhood migraine does not cause changes in posterior ocular structure parameters.

Evaluation of Optical Coherence Tomography to Detect Elevated Intracranial Pressure in Children

Importance

Detecting elevated intracranial pressure in children with subacute conditions, such as craniosynostosis or tumor, may enable timely intervention and prevent neurocognitive impairment, but conventional techniques are invasive and often equivocal. Elevated intracranial pressure leads to structural changes in the peripapillary retina. Spectral-domain (SD) optical coherence tomography (OCT) can noninvasively quantify retinal layers to a micron-level resolution.

Objective

To evaluate whether retinal measurements from OCT can serve as an effective surrogate for invasive intracranial pressure measurement.

Design, Setting, and Participants

This cross-sectional study included patients undergoing procedures at the Children's Hospital of Philadelphia from September 2014 to June 2015. Three groups of patients (n = 79) were prospectively enrolled from the Craniofacial Surgery clinic including patients with craniosynostosis (n = 40). The positive control cohort consisted of patients with hydrocephalus and suspected intracranial hypertension (n = 5), and the negative control cohort consisted of otherwise healthy patients undergoing a minor procedure (n = 34).

Main Outcomes and Measures

Spectral-domain OCT was performed preoperatively in all cohorts. Children with cranial pathology, but not negative control patients, underwent direct intraoperative intracranial pressure measurement. The primary outcome was the association between peripapillary retinal OCT parameters and directly measured elevated intracranial pressure.

Results

The mean (SD) age was 34.6 (45.2) months in the craniosynostosis cohort (33% female), 48.9 (83.8) months in the hydrocephalus and suspected intracranial hypertension cohort (60% female), and 59.7 (64.4) months in the healthy cohort (47% female). Intracranial pressure correlated with maximal retinal nerve fiber layer thickness (r = 0.60, P ≤ .001), maximal retinal thickness (r = 0.53, P ≤ .001), and maximal anterior retinal projection (r = 0.53, P = .003). Using cut points derived from the negative control patients, OCT parameters yielded 89% sensitivity (95% CI, 69%-97%) and 62% specificity (95% CI, 41%-79%) for detecting elevated intracranial pressure. The SD-OCT measures had high intereye agreement (intraclass correlation, 0.83-0.93) and high intragrader and intergrader agreement (intraclass correlation ≥0.94). Conventional clinical signs had low sensitivity (11%-42%) for detecting intracranial hypertension.

Conclusions and Relevance

Noninvasive quantitative measures of the peripapillary retinal structure by SD-OCT were correlated with invasively measured intracranial pressure. Optical coherence tomographic parameters showed promise as surrogate, noninvasive measures of intracranial pressure, outperforming other conventional clinical measures. Spectral-domain OCT of the peripapillary region has the potential to advance current treatment paradigms for elevated intracranial pressure in children.

Evaluation of the effects on choroidal thickness of bimatoprost 0.03% versus a brinzolamide 1.0%/timolol maleate 0.5% fixed combination

OBJECTIVE

To investigate the effects of two different medical treatment options on choroidal thickness (CT) in cases of open-angle glaucoma (OAG).

METHODS

Sixty-seven eyes newly diagnosed with OAG and 52 healthy eyes constituting the control group were included in the study. Glaucomatous eyes were randomly divided into two subgroups; Group I was started on bimatoprost 0.03% and Group II on a brinzolamide 1.0%/timolol maleate 0.5% fixed combination (BTFC). Intraocular pressure (IOP), ocular pulse amplitude (OPA) and subfoveal CT measurements were performed in all eyes in the study before treatment and on weeks 2, 4 and 8 after treatment.

RESULTS

Mean initial IOP values in groups I and II and the control group were 25.5 ± 4.7, 25.1 ± 5.2 and 16.1 ± 2.9 mmHg, mean OPA values were 3.7 ± 1, 3.6 ± 1.4 and 2.4 ± 0.6 mmHg and mean CT values were 269.4 ± 83, 264.5 ± 84.4 and 320.1 ± 56.6 μm, respectively. Eight weeks after treatment, mean IOP values in Groups I and II and the control group were 18.3 ± 2.6, 18.1 ± 3.4 and 15.7 ± 2.9 mmHg, mean OPA values were 2.9 ± 1.2, 2.8 ± 1.5 and 2.3 ± 0.8 mmHg and mean CT values were 290.2 ± 87.3, 271.8 ± 82.5 and 319.3 ± 56.8 μm, respectively. No significant difference was determined in terms of the decrease in IOP and OPA obtained after treatment in Group I and Group II. However, a significant difference was observed between the two groups in terms of choroidal thickening after treatment.

CONCLUSION

The use of topical ocular hypotensive medication in eyes with OAG results in an increase in CT. This increase is relatively greater with bimatoprost 0.03% therapy compared to BTFC.

Thickness of retinal layers in the foveas of children with anisometropic amblyopia

Purpose

To use highly precise spectral-domain optical coherence tomography (SD-OCT) to determine whether there were structural abnormalities in the layers of different regions of the fovea in children with anisometropic amblyopia.

Methods

Eighteen children (mean age 7.8 years old; range 5–11 years) with unilateral anisometropic amblyopia and 18 age-matched control subjects participated. Foveal thickness was measured with an enhanced depth imaging system, SD-OCT and segmented into layers using custom developed software. The thickness of each layer of the fovea was compared among amblyopic eyes, fellow eyes and control eyes with optical magnification correction for axial length and statistical correction for age and sex.

Results

The total thickness and each intra-ocular layer of the central fovea were the same for each group. However, the amblyopic eyes were significantly thicker than the normal control eyes in 2 of 4 quadrants of the peripheral retina. Exploring intra-retinal layers in these two quadrants, the nasal nerve fiber layer (NFL) and inferior inner nuclear layer (INL)were significantly thicker in amblyopic eyes than in control eyes (p = 0.01 and 0.012, respectively, by ANCOVA).

Conclusion

The SD-OCT data revealed marginal differences in some foveal layers at peripheral locations and indicated that structural differences might exist between individuals with amblyopia and visually normal control subjects. However, the differences were scattered and represented no identifiable pattern. More studies with large samples and precise locations of the retinal layers must be performed to extend the present results.

Macular thicknesses and their associations with ocular and demographic variables in black South Africans

Purpose: To determine normal macular thicknesses and their associations with demographic and ocular variables in healthy eyes of black South Africans.Methods: Six hundred healthy subjects (N = 600) underwent height and weight measurements followed by a complete ophthalmic examination, which included auto-refraction, subjective refraction, slit-lamp biomicroscopy, ocular biometric measurements and tonometry. Intraocular pressure (IOP) was measured with the Nidek NT530P (Tonopachy™) and the axial length (AL) thickness with the Nidek Echoscan. The central corneal thickness (CCT) and macular thickness were measured using iVue-100 spectral-domain optical coherence tomography (Optovue, Inc.). The macular thickness map protocol that divides the macular area into nine regions of the Early Treatment Diabetic Retinopathy Study (ETDRS) fields was used. Variations in macular thickness measurements with body mass index (BMI), age, gender, refraction, AL, CCT and IOP were determined with partial correlation analysis.Results: The 600 subjects had a mean age of 28.15 ± 13.09 years (range = 10–66 years), with 305 (50.83%) being males and 295 (49.17%) females. The thickness values of the central, inner and outer maculae were normally distributed, with means of 235.89 µm ± 20.04 µm, 303.56 µm ± 18.68 µm and 287.81 µm ± 14.61 µm, respectively. Mean total macular thickness for all subjects was 268.72 ± 15.04 µm. The temporal quadrant was markedly thinner than all other quadrants for both inner and outer macular regions. Macular thicknesses were greater in men than in women (p < 0.05). The thickness of mean central, mean inner and mean outer maculae increased significantly with increasing BMI (p < 0.001). Central, inner and outer maculae were significantly associated (p < 0.001) with a high hyperopic spherical equivalent refraction. AL was associated with a thin inner macula (p < 0.05) and an outer macula (p < 0.001), but not with a thinner central macula (p > 0.05). Age, CCT and IOP were not associated with macular thickness values in any quadrant (p > 0.05).Conclusion: The macular values were thinner in women than in men and were related to BMI, gender, hyperopic spherical refraction and AL with regional variations. These differences should be considered when interpreting optical coherence tomography results for accurately diagnosing and managing retinal abnormalities.

Macular thickness in healthy Saudi adults. A spectral-domain optical coherence tomography study

Objectives:

To determine the macular thickness in the eyes of healthy Saudi adults using spectral-domain optical coherence tomography (SD-OCT).

Methods:

This is a prospective, cross-sectional study, including 158 healthy participants between August and December 2015. Mean subject age was 29.9 ± 7.85 years old. All participants underwent full ophthalmic evaluation, including SD-OCT imaging, and axial length measurement. Data from the right eye were included. Mean retinal thickness was determined. Correlations between retinal thickness and gender, age, axial length, and spherical equivalence were analyzed.

Results:

Mean central retinal thickness was 244.76 ± 23.62 µm, mean axial length was 23.8 ± 1.062 mm (range: 20.5-29 mm) and mean spherical equivalent was -0.31 ± 1.75 diopters (D) (range: -5.50 to +4.25 D). Central subfield (CSF) thickness and foveal volume were significantly lower in women than in men (both p<0.001). Data from the various age groups did not show statistically significant differences in the CSF thickness (p=0.389) or foveal volume (p=0.341). A positive correlation between CSF thickness and axial length (p<0.001) was observed.

Conclusion:

The normal macular thickness values in healthy Saudi individuals is different from that reported in other ethnic groups, as obtained by SD-OCT. Saudi men had thicker CSF than Saudi women and axial length was positively correlated to the central foveal thickness.

Retinal Fibre Layer Thickness Measurement in Normal Paediatric Population in Sweden Using Optical Coherence Tomography

Purpose. To evaluate the correlation between peripapillary retinal nerve fibre layer (RNFL) thickness and both age and refraction error in healthy children using optical coherence tomography (OCT). Patients and Methods. 80 healthy children with a mean age of 9.1 years (range 3.8 to 16.7 years) undergoing routine ocular examination at the orthoptic section of the Ophthalmology Department were recruited for this cross-sectional study. After applying cycloplegia, the peripapillary RNFL thickness was measured in both eyes using the Topcon 3D OCT 2000 device. Results. 138 eyes were included in the analysis. The average refractive error (SE) was +1.7 D (range -5.25 to +7.25 D). The mean total RNFL thickness was 105 μm ± 10.3, the mean superior RNFL thickness was 112.7 μm ± 16.5, and the mean inferior RNFL thickness was 132.6 μm ± 18.3. We found no statistically significant effect of age on RNFL thickness (ANOVA, f = 0.33, p = 0.56). Refraction was proven to have a statistically significant effect (ANOVA, f = 67.1, p < 0.05) in RNFL measurements. Conclusions. Data obtained from this study may assist in establishing a normative database for a paediatric population. Refraction error should be taken into consideration due to its statistically significant correlation with RNFL thickness.

Volume Averaging of Spectral-Domain Optical Coherence Tomography Impacts Retinal Segmentation in Children

PURPOSE

To determine the influence of volume averaging on retinal layer thickness measures acquired with spectral-domain optical coherence tomography (SD-OCT) in children.

METHODS

Macular SD-OCT images were acquired using three different volume settings (i.e., 1, 3, and 9 volumes) in children enrolled in a prospective OCT study. Total retinal thickness and five inner layers were measured around an Early Treatment Diabetic Retinopathy Scale (ETDRS) grid using beta version automated segmentation software for the Spectralis. The magnitude of manual segmentation required to correct the automated segmentation was classified as either minor (<12 lines adjusted), moderate (>12 and <25 lines adjusted), severe (>26 and <48 lines adjusted), or fail (>48 lines adjusted or could not adjust due to poor image quality). The frequency of each edit classification was assessed for each volume setting. Thickness, paired difference, and 95% limits of agreement of each anatomic quadrant were compared across volume density.

RESULTS

Seventy-five subjects (median age 11.8 years, range 4.3-18.5 years) contributed 75 eyes. Less than 5% of the 9- and 3-volume scans required more than minor manual segmentation corrections, compared with 71% of 1-volume scans. The inner (3 mm) region demonstrated similar measures across all layers, regardless of volume number. The 1-volume scans demonstrated greater variability of the retinal nerve fiber layer (RNLF) thickness, compared with the other volumes in the outer (6 mm) region.

CONCLUSIONS

In children, volume averaging of SD-OCT acquisitions reduce retinal layer segmentation errors.

TRANSLATIONAL RELEVANCE

This study highlights the importance of volume averaging when acquiring macula volumes intended for multilayer segmentation.

Optic Nerve Head Development in Healthy Infants and Children Using Handheld Spectral-Domain Optical Coherence Tomography

Purpose

To determine feasibility of optic nerve head (ONH) imaging and to characterize ONH development in full-term infants without sedation using handheld spectral-domain optical coherence tomography (SD OCT).

Design

Prospective cross-sectional study.

Participants

Three hundred fifty-two children aged between 1 day and 13 years.

Methods

All participants were imaged using handheld SD OCT without sedation during a single scan session. The percentage of successful scans was calculated. Interexaminer reproducibility and differences between right and left eyes were assessed using intraclass correlation coefficients (ICCs). Images were analyzed using ImageJ software. The developmental trajectories over time for ONH parameters were calculated using fractional polynomial modelling.

Main Outcome Measures

Disc and cup diameter (expressed as distance in micrometers and visual angle in degrees), cup depth, Bruch's membrane opening–minimum rim width (BMO-MRW), retinal thickness, and retinal nerve fiber layer (RNFL; 1700 μm and 6° from the disc center).

Results

On average, 70% of participants were imaged successfully. Interexaminer reliability was excellent (ICC, >0.89) for diametric and retinal thickness parameters. Right and left eyes were similar for diametric measurements (ICC, >0.79), but more variable for nasal BMO-MRW, RNFL, and retinal thickness. The mean disc and cup diameter increase by 30% and 40%, respectively, between birth and 13 years of age when expressed as a distance measure, but remained constant (at 5°–5.5° and 2°, respectively) when expressed as a visual angle with reference to the eye nodal point. The peripapillary temporal RNFL demonstrated a marked initial decrease of nearly 35% between birth and approximately 18 months of age. This was followed by a slow increase up to 12 years of age when measured at 1700 μm from the disc center, although there was little change when measured at 6° from the disc center.

Conclusions

We demonstrated feasibility of handheld SD OCT imaging of the ONH in full-term infants and children without anaesthesia or sedation. This is the first in vivo handheld SD OCT study to describe the development of ONH parameters during the critical early years of visual maturation. Our results provide a normative database for use in routine practice and further studies of ONH pathologic features.

Noninvasive methods of detecting increased intracranial pressure

The detection of elevated intracranial pressure (ICP) is of paramount importance in the diagnosis and management of a number of neurologic pathologies. The current gold standard is the use of intraventricular or intraparenchymal catheters; however, this is invasive, expensive, and requires anesthesia. On the other hand, diagnosing intracranial hypertension based on clinical symptoms such as headaches, vomiting, and visual changes lacks sensitivity. As such, there exists a need for a noninvasive yet accurate and reliable method for detecting elevated ICP. In this review, we aim to cover both structural modalities such as computed tomography (CT), magnetic resonance imaging (MRI), ocular ultrasound, fundoscopy, and optical coherence tomography (OCT) as well as functional modalities such as transcranial Doppler ultrasound (TCD), visual evoked potentials (VEPs), and near-infrared spectroscopy (NIRS).

Relationship between Age and Retinal Nerve Fiber Layer Thickness in Normal Children

PURPOSE

To evaluate the effect of age and ocular factors on peripapillary retinal nerve fiber layer (RNFL) thickness in children.

METHOD

A total of 198 normal subjects aged <19 years received a comprehensive ophthalmologic examination, including measurement of visual acuity, axial length, and cycloplegic refraction. Fast optical coherence tomography RNFL scans were obtained and average RNFL thickness was adjusted for ocular magnification. One eye of each subject was randomly selected as the study eye. The correlations between age and other ocular variables were examined.

RESULTS

Mean subject age was 8.61 ± 3.12 years. Average RNFL thickness and ocular magnification-corrected average RNFL thickness were 107.71 ± 11.83 and 103.03 ± 12.53 μm, respectively. There was no significant correlation between observed RNFL thickness and spherical equivalent of the refractive error (SE), axial length, or age (all P >0.05). Corrected RNFL thickness was positively correlated with age and axial length and negatively correlated with SE (P <0.01). Age was negatively correlated with the percent difference between observed and corrected RNFL thickness (P <0.001). Multivariate linear regression analysis showed that both axial length and age were correlated with corrected RNFL thickness in subjects <15 years old (P <0.05).

CONCLUSION

The RNFL thickness is likely to be overestimated in children <15 years old. Additionally, an RNFL thickness increase was observed in children <15 years old. Thus, ocular magnification and RNFL thickness increase should be considered when assessing RNFL thickness in patients <15 years old.

Use of Ocular Coherence Tomography in Children With Idiopathic Intracranial Hypertension-A Single-Center Experience

BACKGROUND

Idiopathic intracranial hypertension is a disorder characterized by elevated intracranial pressure without an identifiable etiology. Detection of papilledema may be challenging and leads to diagnostic uncertainty in evaluating a child for possible idiopathic intracranial hypertension. Ocular coherence tomography has the potential to add accuracy to the diagnosis of idiopathic intracranial hypertension. The goal of the present study was to determine if there was a relationship between severity of papilledema (as determined by direct ophthalmoscopy and confirmed by fundus photography) and measures of ocular coherence tomography in a pediatric population with idiopathic intracranial hypertension.

METHODS

Thirteen pediatric patients were recruited prospectively after diagnosis of either definitive idiopathic intracranial hypertension (with papilledema) or possible idiopathic intracranial hypertension (without papilledema) at Children's Hospital of Michigan over a period of one year. Clinical data and results of initial ocular coherence tomography and visual field testing were collected and statistically analyzed.

RESULTS

The Frisén scale of papilledema significantly correlated with average retinal nerve fiber layer thickness of each eye (r = 0.633, P = 0.02 in right eye and r = 0.868, P = 0.001 in left eye). The retinal nerve fiber layer thickness (mean ± SD) was significantly higher in the definitive group than in the possible group (189 ± 65 μm vs 104 ± 10 μm in right eye, 165 ± 42 μm vs 106 ± 9 μm in left eye, P < 0.01 in both eyes).

CONCLUSIONS

Ocular coherence tomography may be used as a supplementary method to aid in the reliable detection of papilledema in evaluating a child for idiopathic intracranial hypertension.

A review of the human retina with emphasis on nerve fibre layer and macula thicknesses

The retina is the innermost neural layer of the eye, and is the site of transformation of light energy into a neural signal. Knowledge and assessment of the human retinal structural parameters are important for the appropriate diagnosis and management of various ocular diseases. For instance, potentially blinding eye diseases, such as glaucoma and age-related macula degeneration, cause structural changes in the retina. Clinical evidence with ocular coherence tomography also suggests that eyes with glaucoma lose retinal nerve fibre layer and ganglion cells axons before loss of visual function. These losses appear as a visible change in the optic nerve head and can be seen before visual field abnormalities are noticed by the patient. This review discusses certain aspects (anatomical structures, structural changes with eye diseases and assessment methods) involving the human retina, their clinical importance and factors that may influence them. The content of this article will be useful to optometrists and ophthalmologists who assess these parameters in normal patients as well as in those with eye conditions such as glaucoma.Keywords: Retinal parameters; optic disc; nerve fibre layer thickness; macula thickness; glaucoma 

Macular Thickness in Myopia: An OCT Study of Young Chinese Patients

PURPOSES

To investigate macular thickness (MT) in young myopic Chinese patients using Spectralis optical coherence tomography (OCT) and to assess its association with gender, axial length (AL), spherical equivalent (SE), and intraocular pressure (IOP).

METHODS

Included in this study were 133 myopic Chinese patients, aged 18-30 years. All underwent complete ophthalmic examinations and Spectralis OCT. Inner, central, and outer foveal regions of the macula were measured.

RESULTS

The central fovea was the thinnest of the three macular regions (mean thickness, 250.1 ± 15.3 μm). Women had consistently thinner MTs than did men, except in the outer superior and inferior areas. Central foveal thickness (CFT) was positively correlated with AL and negatively correlated with SE. In the inner and outer regions, MT was positively correlated with SE. AL was negatively correlated with MT in all quadrants of the inner and outer sectors, but not the inner superior and outer nasal areas. No macular measurement was significantly correlated with age or IOP in either gender.

CONCLUSIONS

Variables affecting MT should be considered when evaluating SD-OCT data in young myopic Chinese patients, with and without retinal diseases.

Normative Spectral Domain Optical Coherence Tomography Data in Healthy Turkish Children

PURPOSE

To determine the normative database of macular and retinal nerve fiber layer (RNFL) thickness parameters in healthy Turkish children by OCT.

METHODS

318 eyes of 318 children (138 boys, 183 girls) aged between 3 and 17 years were evaluated. The children were scanned by Cirrus HD-OCT (Carl Zeiss Meditec) to measure the macula, RNFL, and optic nerve head parameters.

RESULTS

Axial length (AL) (p < 0.001, R²= 0.08), spherical equivalent (SE) (p < 0.001, R²= 0.12), and rim area (p < 0.001, R²= 0.15) were the strongest predictors of RNFL thickness. All of the macular measurements were significantly related to age (p < 0.001, R²> 5%). Average macular thickness (p < 0.01) and outer macula (p = 0.002) showed significant relationship with the AL and SE.

CONCLUSION

This study ensures an age-adjusted pediatric normative database using OCT to diagnose and monitor macular diseases, optic nerve diseases, and glaucoma in children.

Macular retinal layer thickness in childhood

PURPOSE

To examine macular retinal thickness and retinal layer thickness with spectral domain optical coherence tomography in a population of children with normal ocular health and minimal refractive errors.

METHODS

High-resolution macular optical coherence tomography scans from 196 children aged 4 years to 12 years (mean age: 8 ± 2 years), were analyzed to determine total retinal thickness and thickness of 6 different retinal layers across the central 5 mm of the posterior pole. Automated segmentation with manual correction was used to derive retinal thickness values.

RESULTS

The mean total retinal thickness in the central 1-mm foveal zone was 255 ± 16 μm, and this increased significantly with age (mean increase of 1.8 μm per year) in childhood (P < 0.001). Age-related increases in thickness of some retinal layers were also observed, with changes of the highest statistical significance found in the outer retinal layers in the central foveal region (P < 0.01). Significant topographical variations in thickness of each of the retinal layers were also observed (P < 0.001).

CONCLUSION

Small magnitude, statistically significant increases in total retinal thickness and retinal layer thickness occur from early childhood to adolescence. The most prominent changes seem to occur in the outer retinal layers of the central fovea.

Macular Thickness Assessed with Optical Coherence Tomography in Young Chinese Myopic Patients

Purpose. To evaluate the variations in macular thickness in young Chinese myopic persons and the association with axial length (AL), spherical equivalence refraction (SE), age, intraocular pressure, and sex. Methods. In total, 133 young Chinese myopic subjects between 18 and 30 years of age were selected. The macular thickness was assessed using third-generation optical coherence tomography. AL, intraocular pressure, and SE were also measured. Results. The mean central foveal thickness was 191.1 ± 15.3 µm. The macula was consistently thinner in women than in men. Central foveal thickness had a significant positive correlation with AL and a negative correlation with SE. In the inner and outer regions, the macular thickness had a positive correlation with SE and negative correlation with AL. Conclusions. The retina was thinner in women than in men. Associated with myopic progression and AL extension, the central foveal thickness increased, while the retinal thickness of the inner and outer regions decreased.

Retinal nerve fiber layer thickness in normal Indian pediatric population measured with optical coherence tomography

Purpose:

To measure the peripapillary retinal nerve fiber layer (RNFL) thickness in normal Indian pediatric population.

Subjects and Methods:

120 normal Indian children ages 5-17 years presenting to the Pediatric Clinic were included in this observational cross-sectional study. RNFL thickness was measured with stratus optical coherence tomography (OCT). Children with strabismus or amblyopia, with neurological, metabolic, vascular, or other disorders and those with abnormal optic discs were excluded. One eye of each subject was randomly selected for statistical analysis. The effect of age, refraction and gender on RNFL thickness was investigated statistically.

Result:

OCT measurements were obtained in 120 of 130 (92.3%) subjects. Mean age was 10.8 ± 3.24 years (range 5-17). Average RNFL thickness was (± SD) 106.11 ± 9.5 μm (range 82.26-146.25). The RNFL was thickest inferiorly (134.10 ± 16.16 μm) and superiorly (133.44 ± 15.50 μm), thinner nasally (84.26 ± 16.43 μm), and thinnest temporally (70.72 ± 14.80 μm). In univariate regression analysis, age had no statistical significant effect on RNFL thickness (P =0.7249) and refraction had a significant effect on RNFL thickness (P =0.0008).

Conclusion:

OCT can be used to measure RNFL thickness in children. Refraction had an effect on RNFL thickness. In normal children, variation in RNFL thickness is large. The normative data provided by this study may assist in identifying changes in RNFL thickness in Indian children.

Study of Spectral-Domain Optical Coherence Tomography in Children: Normal Values and Influence of Age, Sex, and Refractive Status

Purpose

To establish normal values for retinal nerve fiber layer (RNFL), macular thickness, and macular volume in children using spectral-domain optical coherence tomography (OCT).

Methods

A descriptive cross-sectional study was performed in healthy children between 3 and 14 years of age. Each child underwent a comprehensive ophthalmic examination that included 3 OCT scans with Spectralis (Heidelberg Engineering, Heidelberg, Germany). All measurements were performed by the same operator, and one eye was randomly selected. The influence of age, sex, and refraction on OCT measurements was analyzed.

Results

The sample consisted of 162 Caucasian subjects, mean age 8.1 ± 3.03 years. The spherical equivalent was 0.03 ± 0.19 D (range ±4 D, astigmatism <1 D). The average values were 263.69 ± 4.54 µm for central macular thickness, 0.21 ± 0.01 mm3 for central macular volume, and 100.45 ± 1.98 µm for RNFL. A significant correlation between RNFL and spherical equivalent was found for the nasal (p = 0.001), inferior (p = 0.009), and inferior nasal (p = 0.005) sectors. No differences were found with regard to sex (p>0.05). However, central macular thickness and central macular volume were correlated with age (p = 0.027, p = 0.02).

Conclusions

This study provides reference values for macular thickness, macular volume, and RNFL in healthy children.

Evaluation of the retinal ganglion cell layer thickness in healthy Turkish children

PURPOSE

To identify the distribution, variation, and determinants of ganglion cell-inner plexiform layer (GC-IPL) thickness in healthy Turkish children measured by high-definition optical coherence tomography (HD-OCT).

PATIENTS AND METHODS

This institutional study involved 296 eyes from 296 healthy children aged between 3 and 17 years. Each child underwent a dilated eye examination, cycloplegic refraction, and axial length measurement using Nidek AL-Scan optical biometer. Macular scan was used to measure the GC-IPL thickness, and peripapillary retinal nerve fiber layer (RNFL) thickness was measured using the HD-OCT (Cirrus HD-OCT). Right eye of each subject was selected for analysis.

RESULTS

A total of 296 children (125 boys, 171 girls) were included in this study. The mean age of the children was 9.62±4.10 years (range, 3 to 17 y). The mean spherical equivalent was -0.09±1.49 D. The mean AL was 23.03±1.03 mm. The mean overall GC-IPL thickness was 83.44±5.52 μm and RNFL thickness was 96.91±10.21 μm. They were thicker than has been reported in adults. According to age-adjusted multiple regression analyses significant predictors of mean GC-IPL thickness were peripapillary RNFL thickness and AL (P<0.001).

CONCLUSIONS

This study ensures a pediatric normative database of GC-IPL using spectral-domain OCT. This information may provide to diagnosis and monitoring of optic nerve diseases and glaucoma in children.

Macular thickness assessed with spectral domain OCT in a population-based study of children: normative data, repeatability and reproducibility and comparison with time domain OCT

PURPOSE

To collect data on macular thickness assessed with Cirrus OCT in healthy children in a population-based study, to examine the repeatability and reproducibility, and to compare the values with Stratus OCT.

METHODS

Fifty-eight 6- to 15-year-old children, born at term, were examined. Best-corrected visual acuity and refraction were assessed. One examiner performed three OCT assessments, and the repeatability was calculated. Thereafter, a second examiner repeated the examinations to calculate the reproducibility. One eye was randomized to be included in the normal material. Finally, the second examiner assessed the macular thickness with the Stratus OCT.

RESULTS

The mean value (±SD) of central macular thickness was 255 ± 17 μm, and the total macular volume was 10.3 ± 0.5 mm(3) . No correlations were found between macular thickness and age, gender or refraction. The coefficients of variance (CoVs) for both repeatability and reproducibility were <1.21%, and the intraclass correlations (ICCs) were over 0.86. The Cirrus OCT showed a 29% thicker central macular thickness than the Stratus OCT.

CONCLUSION

Normal values for macular thickness assessed with Cirrus OCT in healthy full-term children in a population-based study were reported. The assessments showed high repeatability and reproducibility. The values of Cirrus and Stratus OCT differed and the techniques were not interchangeable.

Megalopapilla in children: a spectral domain optical coherence tomography analysis

PURPOSE

To compare various optic nerve head (ONH) parameters and peripapillary retinal nerve fibre layer (pRNFL) thickness between megalopapilla cases and normal control using spectral domain optical coherence tomography (SD-OCT) in children.

METHODS

Fifty eyes with megalopapilla and 80 normal control eyes of totally 130 children between the ages of 6 and 15 were examined using SD-OCT. Optic nerve head parameters including disc diameter, cup-to-disc ratio, disc area, cup area, rim area, cup volume and rim volume, and pRNFL thickness were analysed and compared between two groups.

RESULTS

Megalopapilla group presented larger optic disc diameter, disc and cup area, cup-to-disc and cup-to-disc area ratio, when compared with normal control group. However, there is no difference in rim area (p = 0.25) and rim volume (p = 0.48) between the two groups. Average pRNFL thickness was higher in the megalopapilla group (p < 0.001).

CONCLUSIONS

Rim area, rim volume and pRNFL, which reflect the number of retinal nerve fibres, were preserved in children with megalopapilla. Various ONH parameters obtained with SD-OCT may be useful in the differential diagnosis of megalopapilla in children.

Applications of optical coherence tomography in pediatric clinical neuroscience

For nearly two centuries, the ophthalmoscope has permitted examination of the retina and optic nerve-the only axons directly visualized by the physician. The retinal ganglion cells project their axons, which travel along the innermost retina to form the optic nerve, marking the beginning of the anterior visual pathway. Both the structure and function of the visual pathway are essential components of the neurologic examination as it can be involved in numerous acquired, congenital and genetic central nervous system conditions. The development of optical coherence tomography now permits the pediatric neuroscientist to visualize and quantify the optic nerve and retinal layers with unprecedented resolution. As optical coherence tomography becomes more accessible and integrated into research and clinical care, the pediatric neuroscientist may have the opportunity to utilize and/or interpret results from this device. This review describes the basic technical features of optical coherence tomography and highlights its potential clinical and research applications in pediatric clinical neuroscience including optic nerve swelling, optic neuritis, tumors of the visual pathway, vigabatrin toxicity, nystagmus, and neurodegenerative conditions.

Assessment of retinal nerve fiber layer thickness in healthy, full-term neonates

PURPOSE

To measure average retinal nerve fiber layer (RNFL) thicknesses in healthy, full-term neonates.

DESIGN

Descriptive research to develop normative data.

METHODS

Healthy infants born between 37 and 42 weeks postmenstrual age were imaged with hand-held spectral-domain optical coherence tomography. A custom script segmented the RNFL; the fovea and optic nerve center were manually selected. A second script measured the average RNFL thickness along the papillomacular bundle, defined as the arc from -15 degrees to +15 degrees on the axis from the optic nerve to fovea, with radii of 1.1, 1.3, 1.5, and 1.7 mm from the center of the optic disc. Shapiro-Wilk W tests assessed these measurements for normality to determine the age-appropriate radial distance for subsequent analyses. Average RNFL thicknesses for four temporal 45-degree sectors (superior temporal, temporal superior, temporal inferior, and inferior temporal) and the temporal quadrant were calculated and compared to demographic parameters for all infants.

RESULTS

Fifty full-term infants were adequately imaged for RNFL analysis. RNFL thicknesses at 1.5 mm radial distance from the optic nerve were the most normally distributed. While there was a trend toward greater mean superior temporal RNFL thickness for both black and Hispanic vs white infants (128 ± 27 μm, 124 ± 30 μm, and 100 ± 19 μm, respectively, P = .04 for both comparisons), there were no other significant differences noted in RNFL thicknesses by race, sex, gestational age, or birth weight.

CONCLUSIONS

We present RNFL thickness measurements for healthy, full-term infants that may serve as normative data for future analyses.

Using spectral-domain optical coherence tomography to detect optic neuropathy in patients with craniosynostosis

BACKGROUND

Detecting and monitoring optic neuropathy in patients with craniosynostosis is a clinical challenge due to limited cooperation, and subjective measures of visual function. The purpose of this study was to appraise the correlation of peripapillary retinal nerve fiber layer (RNFL) thickness measured by spectral-domain ocular coherence tomography (SD-OCT) with indication of optic neuropathy based on fundus examination.

METHODS

The medical records of all patients with craniosynostosis presenting for ophthalmic evaluation during 2013 were retrospectively reviewed. The following data were abstracted from the record: diagnosis, historical evidence of elevated intracranial pressure, current ophthalmic evaluation and visual field results, and current peripapillary RNFL thickness.

RESULTS

A total of 54 patients were included (mean age, 10.6 years [range, 2.4-33.8 years]). Thirteen (24%) had evidence of optic neuropathy based on current fundus examination. Of these, 10 (77%) demonstrated either peripapillary RNFL elevation and papilledema or depression with optic atrophy. Sensitivity for detecting optic atrophy was 88%; for papilledema, 60%; and for either form of optic neuropathy, 77%. Specificity was 94%, 90%, and 83%, respectively. Kappa agreement was substantial for optic atrophy (κ = 0.73) and moderate for papilledema (κ = 0.39) and for either form of optic neuropathy (κ = 0.54). Logistic regression indicated that peripapillary RNFL thickness was predictive of optic neuropathy (P < 0.001). Multivariable analysis demonstrated that RNFL thickness measurements were more sensitive at detecting optic neuropathy than visual field testing (likelihood ratio = 10.02; P = 0.002). Sensitivity and specificity of logMAR visual acuity in detecting optic neuropathy were 15% and 95%, respectively.

CONCLUSIONS

Peripapillary RNFL thickness measured by SD-OCT provides adjunctive evidence for identifying optic neuropathy in patients with craniosynostosis and appears more sensitive at detecting optic atrophy than papilledema.

Intra- and inter-visit reproducibility of ganglion cell-inner plexiform layer measurements using handheld optical coherence tomography in children with optic pathway gliomas

PURPOSE

To determine the intra- and inter-visit reproducibility of ganglion cell-inner plexiform layer thickness measures using handheld optical coherence tomography (OCT) in sedated children with optic pathway gliomas and/or neurofibromatosis type 1 (NF1).

DESIGN

Prospective longitudinal cohort study.

METHODS

Children with sporadic optic pathway gliomas and/or NF1 who had ≥2 volumes acquired over the macula using handheld OCT during sedation for clinically indicated magnetic resonance imaging were eligible for the intra-visit cohort. Children with repeat handheld OCT imaging within 6 months were eligible for the inter-visit cohort. Total retinal thickness and ganglion cell-inner plexiform layer thickness were measured using custom-designed automated segmentation software. Reproducibility was compared across average and anatomic quadrant by calculating the coefficient of variation (CV) and intraclass correlation coefficient (ICC).

RESULTS

Forty-two subjects (median age 5.4 years, range 0.8-12.7 years) contributed 45 eyes to the intra-visit cohort. Thirty-one subject eyes had normal vision and 14 had abnormal vision (decreased visual acuity and/or visual field). Average and quadrant ganglion cell-inner plexiform layer measures demonstrated CVs ≤4.5% with excellent ICCs (>0.935). The superior quadrant CV differed between subjects with (4.4%) and without (2.1%) vision loss (P < .05). Twenty-five subject eyes were eligible for the inter-visit cohort, demonstrating CVs from 1.6% to 5.2%. Inter-visit ICCs were excellent (0.955-0.995).

DISCUSSION

Handheld OCT imaging in sedated children with optic pathway gliomas produces highly reproducible measures of ganglion cell-inner plexiform layer thickness.

Evaluation of choroidal thickness in ankylosing spondylitis using optical coherence tomography

Abstract Purpose: To investigate posterior segment (PS) findings in the eye in patients with ankylosing spondylitis (AS).

METHODS

Eighty-four patients with AS and 63 healthy controls were enrolled. PS evaluations were performed using optical coherence tomography (OCT). Foveal thickness, peripapillary retinal nerve fiber layer thickness, macular volume, ganglion cell complex, and choroidal thickness (CT) values were compared between the groups.

RESULTS

Mean CT was higher in patients with AS (326.5 ± 71.5 µm) than in the healthy controls (286.2 ± 59.5 µm) (p = 0.001). There was no significant difference between patients with AS and the healthy control group in terms of other OCT parameters. There was also no significant correlation between CT, AS activity index, and disease duration.

CONCLUSIONS

This is the first study to evaluate effects of AS on CT. CT was high in patients with AS compared to healthy controls.

Optical coherence tomography in pediatric ophthalmology: current roles and future directions

The application of existing optical coherence tomography (OCT) technology to the pediatric population is limited in both the design specification of the device and its hardware. However, the potential of OCT in the pediatric population has not been fully realized. The authors review the literature, highlighting the currently available spectral-domain OCT technology and summarizing the reported normal pediatric OCT parameters for retinal nerve fiber layer and macular thickness. They also review the pediatric ophthalmological conditions in which OCT has been used and discuss advancements in OCT design and their potential applications to the pediatric population. The use of OCT in pediatric populations is likely to increase greatly in the coming years, aiding clinical decision-making and providing new insights into pediatric disease pathophysiology.

Spectral domain optical coherence tomography in children: normative data and biometric correlations

Background

The aim was to report normative values of retinal nerve fiber layer (RNFL) and macular parameters in children using spectral domain optical coherence tomography (OCT) and to perform correlations with age, refractive error and axial length.

Methods

This was an observational cross-sectional study recruiting 113 healthy children aged 6 to 17 years with no ocular abnormality except refractive error. After a comprehensive eye examination and axial length measurement, RNFL and macular thickness measurements were performed using the Cirrus OCT machine. Main outcome measures were macular volume, macular thickness and RNFL thickness values as well as their correlations with age, refractive error and axial length. Right eyes of all subjects were selected for analysis.

Results

One hundred and eight children were included in the study, 65 females and 43 males. Mean age was 10.7+/−3.1 years, average spherical equivalent refraction (SE) was −0.02+/−1.77(−4.25 to +5.00) diopters and average axial length was 23.5+/−1.0 (21.5 to 25.8)mm. Mean RNFL thickness was 95.6+/−8.7 μm, average macular thickness was 279.6+/−12.5 μm, central macular thickness was 249.1+/−20.2 μm, and mean macular volume was 10.1+/−0.5 mm³. Central macular thickness values were significantly higher in males (p < 0.001). RNFL measurements did not correlate with age but did show a positive correlation with SE. All macular parameters were consistently positively correlated with age and most of them were positively correlated with SE. When controlling for axial length, only the macular inner circle thickness was positively correlated with age.

Conclusions

Using Cirrus OCT, normative RNFL and macular parameters in healthy children below 18 years of age were established; measurements varied by age and gender.

Peripapillary retinal nerve fiber layer and foveal thickness in hypermetropic anisometropic amblyopia

Purpose

To evaluate whether there was a difference in peripapillary retinal nerve fiber layer (RNFL) and foveal thickness between amblyopic and normal individuals with optical coherence tomography.

Materials and methods

Sixty patients, 30 patients with hypermetropic anisometropic amblyopia and 30 normal emmetropic subjects, were enrolled in this study. The eyes of the participants were divided into three groups: 30 eyes of 30 patients with amblyopia (A), 30 fellow eyes of the amblyopic patients (B), and 30 eyes of 30 normal subjects (C). Emmetropic normal subjects included cases with normal visual acuity and unremarkable ocular examinations. After routine ophthalmic examination, peripapillary retinal nerve fiber layer and foveal thickness measurements were measured by time-domain optical coherence tomography and compared among the three groups.

Results

The difference in RNFL thickness between amblyopic eyes, fellow eyes of the amblyopic patients, and normal eyes of the emmetropic subjects was not clinically significant. However, the mean foveal thickness was significantly thicker in amblyopic eyes versus the fellow eyes and normal subjects’ eyes.

Conclusion

Our results suggest that amblyopia seems to have an effect on the foveal thickness, but not on the RNFL thickness.

Development of macular edema and impact on visual acuity in uveitis associated with juvenile idiopathic arthritis

PURPOSE

To investigate the development of macular edema (ME) in relation to the duration of uveitis and visual outcome in uveitis associated with juvenile idiopathic arthritis (JIA).

METHODS

Sixty-one patients with JIA-uveitis (116 eyes) were investigated by Cirrus OCT for macular thickness. The relation between macular thickness and time interval since onset of uveitis and best corrected visual acuity (BCVA) was analyzed by linear mixed effect models.

RESULTS

Duration of follow-up showed significant positive linear relation with central macular thickness. The central macular thickness showed a significant linear relation with BCVA, but not with disease activity. Thirteen patients developed ME (central field thickness >304.4 µm) after a mean time interval of 11.6 years. Thirteen patients had macular thinning after a significant longer interval of uveitis compared to patients with normal or thickened macula.

CONCLUSIONS

Duration of JIA-uveitis is positively correlated with the development of ME, compromising the visual acuity.

Biometry and spectral domain optical coherence tomography parameters in children with large cupping

PURPOSE

The purpose of this study is to investigate optic nerve head using spectral domain optical coherence tomography (SD-OCT) in children with large cupping.

METHODS

111 eyes (4-10 years) were divided into three groups according to the cup to disc ratio: group 1, ≤0.3; group 2, 0.4-0.6; and group 3, ≥0.7. The rim area, disc area, average cup to disc ratio, vertical cup to disc ratio, and cup volume were investigated using SD-OCT (Cirrus HD-OCT, Carl Zeiss, Jena, Germany), and the axial length and anterior chamber depth (ACD) were measured by IOL master (IOL master 500, Carl Zeiss, Jena, Germany). Next, we compared ocular biometry and SD-OCT between the three groups.

RESULTS

The mean age of group 1 was 6.48 ± 1.42 years, 7.00 ± 1.75 years in group 2, and 6.63 ± 1.82 years in group 3 (p = 0.370). A significant difference was seen in the spherical equivalent between the groups (p = 0.001). Group 2 had the most myopic refractive errors. As the cup to disc ratio increases, disc area, average cup to disc ratio, vertical cup to disc ratio, and cup volume increase significantly. When the results of ocular biometry and SD-OCT are adjusted for axial length, only disc area showed a significant correlation with cup to disc ratio (ACD: p = 0.473, rim area: p = 0.639, disc area: p = 0.005, and cup volume: p = 0.325).

CONCLUSION

Axial length is the key factor determining disc size, which in turn is important for determining cup to disc ratio. Normal children with large cupping should be examined for axial length, myopic refractive errors, and disc size.