Characteristic deviations of the optic disc and macula in optic nerve hypoplasia based on OCT.

PURPOSE: The purpose of this study was to evaluate the optic disc and macula in a large cohort of patients with different severity of optic nerve hypoplasia (ONH) using high-resolution spectral domain optical coherence tomography (SD-OCT). METHODS: In total, 36 patients (52 ONH eyes and 17 fellow eyes in unilateral cases) and 45 healthy right eyes from 45 controls were evaluated. All patients underwent an examination to confirm the diagnosis. SD-OCT images of the disc and macula were obtained and analysed both quantitatively and qualitatively. RESULTS: OCT in ONH eyes demonstrated a shorter disc diameter (1061 ± 375 µm vs. 1751 ± 221 µm, p < 0.001), shallower mean cup depth (427 ± 171 µm vs. 551 ± 152 µm, p = 0.01), thinner ganglion cell complex (GCC) perifoveally (47.3 ± 13.0 µm, 60.8 ± 6.0 µm, p < 0.001) and reduced foveal depth (61 ± 36 µm, 119 ± 19 µm, p < 0.001) compared to control eyes. Qualitative analysis showed that 1/3rd of ONH eyes lacked signs of an optic cup, and 2/3rd had reduced or no sign of a foveal pit. Fellow eyes had shorter disc diameter (1446 ± 404 µm vs. 1751 ± 221 µm, p = 0.004) and reduced foveal depth (93 ± 27 µm vs. 119 ± 19 µm, p < 0.001) but similar GCC thickness (60.8 ± 7.1 µm vs. 60.8 ± 6.0 µm, p = 0.738) compared to controls. Disc diameter showed the best correlation with visual acuity in ONH eyes (ρ = 0.517, p < 0.001). CONCLUSION: ONH eyes have reduced GCC thickness and reduced or no foveal pit. Fellow eyes in presumed unilateral cases have a smaller disc diameter and reduced foveal depth compared to controls, suggesting the possibility of subclinical/mild disease. However, GCC thickness was normal. The correlation between structure and visual function is not always straightforward.

Optical Coherence Tomography Can Predict Visual Acuity in Children with Optic Nerve Hypoplasia.

Purpose: Optic nerve hypoplasia (ONH) is a common cause of visual impairment in children. Clinical complexity can cause diagnostic delay and difficulties predicting visual outcome. We evaluated whether optical coherence tomography (OCT) can improve the diagnosis and prediction of vision. Methods: Thirty-seven eyes with ONH from 12 girls and 8 boys, median age 10.5 years (range 2.8-18.9 years), were included in this cross-sectional cohort study. The majority, 17/20, had bilateral ONH. Ophthalmological assessments included best corrected visual acuity (BCVA), fundus photography, measurement of the peripapillary retinal nerve fibre layer (pRNFL), macular ganglion cell complex (GCC), Bruch's membrane opening (BMO) and visual fields. We compared OCT parameters with comparison data collected on 140 healthy individuals 5 to 25 years old. Pearson's correlation coefficient was used to determine the correlation of OCT parameters and BCVA. Results: OCT demonstrated thinner mean pRNFL (p < 0.001) and mean GCC compared to the reference material (p < 0.001). BCVA displayed a strong or moderate correlation to pRNFL and to all sectors of the GCC except the inferotemporal. BCVA correlated strongly to Bruch's membrane opening (BMO) (0.71, p < 0.001), and moderately to the Zeki ratio (-0.52, p < 0.001). Multivariate analyses showed that BMO explained 48% of the variance in BCVA. Visual fields correlated strongly to pRNFL and GCC thickness. GCC thinning corresponded to visual field defects presence and location. Conclusion: OCT can facilitate the diagnosis of ONH. Parameters such as pRNFL, GCC and BMO can be predictors of visual acuity whereas GCC and pRNFL thinning can indicate location and severity of visual field defects.

[Important to evaluate children with visual impairment]. / Viktigt att överväga utredning av barn med optikusmissbildningar.

Congenital optic disc malformations can cause visual impairment. Diagnostics can be challenging during early infancy and childhood and visual prognosis difficult to predict; optical coherence tomography may be of value. The children often have coexisting comorbidities like pituitary hormone deficiency, neurodevelopmental disorders, and neurological impairments, and evaluation by a pediatrician should be performed. Also, genetic analyses should be considered. Co-operation in multidisciplinary teams is of value for correct diagnosis, visual habilitation and treatment of hormonal and neurological dysfunctions.

Optic Disc Coloboma in children - prevalence, clinical characteristics and associated morbidity.

PURPOSE: The aim of the study was to report prevalence, ocular outcome, neurological characteristics, cognitive and behavioural problems in children with optic disc coloboma (ODC). METHODS: This was a population-based, cross-sectional study of 31 children between 2 and 18 years of age diagnosed with ODC. The children were part of a larger cohort of 184 children with congenital optic disc malformations. Clinical ophthalmological examinations, neurological assessments, behavioural and developmental screening were performed. RESULTS: The prevalence of ODC was 8.9/100 000 children. Of the 31 patients, 18 had unilateral ODC (p = 0.21). The best-corrected visual acuity (BCVA) in the ODC eye ranged from blindness to 1.3 (median 0.3). BCVA was 0.82 in eyes with an isolated ODC (range 0.4-1.3) and 0.15 (range 0-0.5) in eyes with concurrent macular involvement (p < 0.0001). Nystagmus was observed more often in patients with bilateral ODC (9/13 versus 3/17, p = 0.004). Two patients had retinal detachment. Behavioural/psychological screening was performed in 21 patients with severe deficits identified in six cases. Intellectual disability was present in seven patients. Neurological dysfunction was diagnosed in 8/22 cases. All of the above children had already systemic diagnoses before the ODC diagnosis was made. CONCLUSIONS: ODC was the second most common optic disc malformation in this cohort after optic nerve hypoplasia. The children had a wide range of ocular comorbidity. An isolated ODC without macular involvement was not associated with profound vision loss. The ability of screening in the regular child care centres to diagnose extraocular comorbidities was very good and referral to a paediatrician appears redundant in cases of normal development.