Retinal Imaging of Infants on Spectral Domain Optical Coherence Tomography

Ocular Effects of Prenatal Carotenoid Supplementation in the Mother and Her Child: The Lutein and Zeaxanthin in Pregnancy (L-ZIP) Randomized Trial - Report Number 2

Purpose

Lutein (L) and zeaxanthin (Z) are xanthophyll carotenoids that have been promoted to enhance maternal health and infant visual and neurodevelopment. In this study, we determined the effects of prenatal L and Z supplementation on systemic and ocular carotenoid status in the mother and her newborn infant (NCT03750968). This report focuses on the ocular effects of prenatal carotenoid supplementation.

Design

A prospective randomized clinical trial with 47 subjects randomly assigned by 1:1 allocation to receive standard-of-care prenatal vitamins along with 10 mg L and 2 mg Z softgel (Carotenoid Group) or standard-of-care prenatal vitamins with a placebo softgel (Control Group) starting in the first trimester.

Subjects

We enrolled low-risk pregnancy subjects aged ≥18 years from the obstetrics and gynecology clinic of the University of Utah Hospital.

Methods

Maternal macular, skin, and serum carotenoid concentrations were measured using autofluorescence imaging, resonance Raman spectroscopy, and high-performance liquid chromatography, respectively. Infants' ocular carotenoids and retinal architecture were measured by blue light reflectance imaging and spectral-domain OCT, respectively.

Main Outcome Measures

Changes in maternal and infant macular pigment, skin, and serum carotenoid status over the study period. Differences in infants' retinal maturity indicators between the 2 study groups.

Results

Following supplementation, there was a statistically significant increase in maternal macular pigment optical volume (P < 0.001) in the Carotenoid Group relative to the Control Group at all study time points, and there was no detectable maternal ocular carotenoid depletion. Infant skin and serum carotenoids increased significantly in the Carotenoid Group compared with the Control Group. As exploratory endpoints, infants in the Carotenoid Group had a 20% increase in macular pigment optical density (P = 0.242) and more mature foveal parameters compared with those in the Control Group.

Conclusion

Prenatal carotenoid supplementation significantly increased maternal and infant systemic carotenoids and caused a pattern of increased infant ocular carotenoid status, which may benefit both mothers and their infants' ocular development and function. This study provides important data to design and power a future multicenter study of prenatal carotenoid supplementation in higher-risk pregnancies.

Financial Disclosures

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Ophthalmic sequelae of prematurity in late childhood and adulthood: A review

Advances in the care of premature infants have resulted in unprecedented rates of survival of these infants into adulthood, including those born at very low gestational ages. Ophthalmologists have historically followed premature infants to assess for the presence of and potential need for treatment of retinopathy of prematurity. However, a growing body of literature suggests that the ophthalmic consequences of prematurity extended beyond retinopathy of prematurity and that ophthalmic sequelae of prematurity can endure through adulthood even among formerly preterm adults who were never diagnosed with retinopathy of prematurity. These abnormalities can include a range of both anterior segment and posterior segment sequelae, including higher rates of corneal aberrations, ocular hypertension, strabismus, foveal anomalies, and retinal tears and detachments. This review aims to summarise this literature, underscoring the importance of lifelong examinations and regular monitoring for these complications among adults who were born prematurely.

Five degrees-of-freedom mechanical arm with remote center of motion (RCM) device for volumetric optical coherence tomography (OCT) retinal imaging

Handheld optical coherence tomography (HH-OCT) is gaining popularity for diagnosing retinal diseases in neonates (e.g. retinopathy of prematurity). Diagnosis accuracy is degraded by hand tremor and patient motion when using commercially available handheld retinal OCT probes. This work presents a low-cost arm designed to address ergonomic challenges of holding a commercial OCT probe and alleviating hand tremor. Experiments with a phantom eye show enhanced geometric uniformity and volumetric accuracy when obtaining OCT scans with our device compared to handheld imaging approaches. An in-vivo porcine volumetric image was also obtained with the mechanical arm demonstrating clinical deployability.

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).

The origins of the full-field flash electroretinogram b-wave

The electroretinogram (ERG) measures the electrical activity of retinal neurons and glial cells in response to a light stimulus. Amongst other techniques, clinicians utilize the ERG to diagnose various eye diseases, including inherited conditions such as cone-rod dystrophy, rod-cone dystrophy, retinitis pigmentosa and Usher syndrome, and to assess overall retinal health. An ERG measures the scotopic and photopic systems separately and mainly consists of an a-wave and a b-wave. The other major components of the dark-adapted ERG response include the oscillatory potentials, c-wave, and d-wave. The dark-adapted a-wave is the initial corneal negative wave that arises from the outer segments of the rod and cone photoreceptors hyperpolarizing in response to a light stimulus. This is followed by the slower, positive, and prolonged b-wave, whose origins remain elusive. Despite a large body of work, there remains controversy around the mechanisms involved in the generation of the b-wave. Several hypotheses attribute the origins of the b-wave to bipolar or Müller glial cells or a dual contribution from both cell types. This review will discuss the current hypothesis for the cellular origins of the dark-adapted ERG, with a focus on the b-wave.

Posterior Segment Optical Coherence Tomography in Uncooperative Paediatric Patients Using Exo-Illumination and Microscope-Integrated Optical Coherence Tomography

BACKGROUND AND OBJECTIVE

To describe a non-invasive technique for the acquisition of retinal optical coherence tomography (OCT) scans in paediatric patients undergoing examination under general anaesthesia (EUA) using microscope-integrated OCT (MIOCT).

STUDY DESIGN

Prospective observational study Methods and Material: The study included 10 paediatric patients undergoing EUA for posterior segment pathology. These patients underwent OCT using MIOCT. No sclerotomy was made during imaging. The fundus was externally illuminated with a 25 gauge endoilluminator probe placed at the limbus and directed towards the posterior pole to aid in image acquisition by MIOCT (exo-illumination). Imaging for all patients was done by two trained vitreoretinal surgeons independently. Acquisition time was recorded for each surgeon. Interobserver variability in acquisition time and image quality was assessed to estimate the reliability of the novel imaging technique.

RESULTS

In nine cases (90%), MIOCT successfully imaged the posterior segment pathology while in one case (10%) of X-linked retinoschisis, it failed to detect an inner retinal break located anteriorly at the equator. The mean acquisition time for surgeons one and two was 211.75 ± 26.00 and 212.58 ± 23.47 seconds, respectively. There was no significant difference in total image acquisition time between the two surgeons (P = 1.0) and the findings of both surgeons were comparable for structural morphology. 4x4 mm-sized scans provided the best delineation in macular pathology, while a 16x16 mm scan size was best suited for localising the area of interest and post-equatorial pathology.

CONCLUSION

Using this technique acquisition of posterior segment OCT scans can be achieved non-invasively, using exo-illumination and MIOCT in paediatric patients undergoing EUA.

Normal and abnormal foveal development

Normal foveal development begins in utero at midgestation with centrifugal displacement of inner retinal layers (IRLs) from the location of the incipient fovea. The outer retinal changes such as increase in cone cell bodies, cone elongation and packing mainly occur after birth and continue until 13 years of age. The maturity of the fovea can be assessed invivo using optical coherence tomography, which in normal development would show a well-developed foveal pit, extrusion of IRLs, thickened outer nuclear layer and long outer segments. Developmental abnormalities of various degrees can result in foveal hypoplasia (FH). This is a characteristic feature for example in albinism, aniridia, prematurity, foveal hypoplasia with optic nerve decussation defects with or without anterior segment dysgenesis without albinism (FHONDA) and optic nerve hypoplasia. In achromatopsia, there is disruption of the outer retinal layers with atypical FH. Similarly, in retinal dystrophies, there is abnormal lamination of the IRLs sometimes with persistent IRLs. Morphology of FH provides clues to diagnoses, and grading correlates to visual acuity. The outer segment thickness is a surrogate marker for cone density and in foveal hypoplasia this correlates strongly with visual acuity. In preverbal children grading FH can help predict future visual acuity.

Peripheral OCT Assisted by Scleral Depression in Retinopathy of Prematurity

OBJECTIVE

To determine whether handheld widefield optical coherence tomography (OCT) can be used to document retinopathy of prematurity (ROP) stage while using scleral depression to improve peripheral views.

DESIGN

Prospective observational study.

PARTICIPANTS

Consecutive neonates admitted to the neonatal intensive care unit (NICU) in a single academic medical center who also met criteria for ROP screening and consented for research imaging.

METHODS

Scleral depression was combined with widefield OCT using an investigational 400-kHz, 55-degree field of view handheld OCT during routine ROP screening from October 28, 2020 to March 03, 2021.

MAIN OUTCOME MEASURES

Acquisition of en face and B-scan imaging of the peripheral retina to objectively assess early vitreoretinal pathology, including the demarcation between vascularized and anterior avascular retina, the presence of early ridge formation, and small neovascular tufts.

RESULTS

Various stages of ROP were detected using a rapid acquisition OCT system. In one neonate, serial OCT imaging over a five-week period demonstrated accumulation of neovascular tufts with progression to stage 3 ROP with extraretinal fibrovascular proliferation along the ridge. Videography of this technique is included in this report for instructional purposes.

CONCLUSIONS

Serial examinations using widefield OCT and scleral depression is feasible and may improve detection and documentation of ROP disease progression. Earlier detection of ROP-related proliferation may prevent vitreoretinal traction, retinal detachment, and blindness.

Quantitative Optical Coherence Tomography for Longitudinal Monitoring of Postnatal Retinal Development in Developing Mouse Eyes

A better study of postnatal retinal development is essential for the in-depth understanding of the nature of the vision system. To date, quantitative analysis of postnatal retinal development is primarily limited to endpoint histological examination. This study is to validate in vivo optical coherence tomography (OCT) for longitudinal monitoring of postnatal retinal development in developing mouse eyes. OCT images of C57BL/6J mice were recorded from postnatal day (P) 14 to P56. Three-dimensional (3D) frame registration and super averaging were adopted to investigate the fine structure of the retina. Quantitative OCT analysis revealed distinct outer and inner retinal layer changes, corresponding to eye development. At the outer retina, external limiting membrane (ELM) and ellipsoid zone (EZ) band intensities gradually increased with aging, and the IZ band was detectable by P28. At the inner retina, a hyporeflective layer (HRL) between the nerve fiber layer (NFL) and inner plexiform layer (IPL) was observed in developing eyes and gradually disappeared with aging. Further image analysis revealed individual RGCs within the HRL layer of the young mouse retina. However, RGCs were merged with the NFL and the IPL in the aged mouse retina. Moreover, the sub-IPL layer structure was observed to be gradually enhanced with aging. To interpret the observed retinal layer kinetics, a model based on eyeball expansion, cell apoptosis, and retinal structural modification was proposed.

Comparing Retinal Structure in Patients with Achromatopsia and Blue Cone Monochromacy Using OCT

Purpose

To compare foveal hypoplasia and the appearance of the ellipsoid zone (EZ) at the fovea in patients with genetically confirmed achromatopsia (ACHM) and blue cone monochromacy (BCM).

Design

Retrospective, multi-center observational study.

Subjects

Molecularly confirmed patients with ACHM (n = 89) and BCM (n = 33).

Methods

We analyzed high-resolution spectral domain optical coherence tomography (SD-OCT) images of the macula from aforementioned patients with BCM. Three observers independently graded SD-OCT images for foveal hypoplasia (i.e. retention of one or more inner retinal layers at the fovea) and four observers judged the integrity of the EZ at the fovea, based on an established grading scheme. These measures were compared with previously published data from the ACHM patients.

Main Outcome Measures

Presence of foveal hypoplasia and EZ grade.

Results

Foveal hypoplasia was significantly more prevalent in ACHM than in BCM (p<0.001). In addition, we observed a significant difference in the distribution of EZ grades between ACHM and BCM, with grade II EZ being by far the most common phenotype in BCM (61% of patients). In contrast, ACHM patients had a relatively equal prevalence of EZ grades I, II, and IV. Interestingly, grade IV EZ was 2.6 times more prevalent in ACHM compared to BCM, while grade V EZ (macular atrophy) was present in 3% of both the ACHM and BCM cohorts.

Conclusions

The higher incidence of foveal hypoplasia in ACHM than BCM supports a role for cone activity in foveal development. Although there are differences in EZ grades between these conditions, the degree of overlap suggests EZ grade is not sufficient for definitive diagnosis, in contrast to previous reports. Analysis of additional OCT features in similar cohorts may reveal differences with greater diagnostic value. Finally, the extent to which foveal hypoplasia or EZ grade is prognostic for therapeutic potential in either group remains to be seen, but motivates further study.

Imaging the pediatric retina: An overview

Recent decade has seen a shift in the causes of childhood blinding diseases from anterior segment to retinal disease in both developed and developing countries. The common retinal disorders are retinopathy of prematurity and vitreoretinal infections in neonates, congenital anomalies in infants, and vascular retinopathies including type 1 diabetes, tumors, and inherited retinal diseases in children (up to 12 years). Retinal imaging helps in diagnosis, management, follow up and prognostication in all these disorders. These imaging modalities include fundus photography, fluorescein angiography, ultrasonography, retinal vascular and structural studies, and electrodiagnosis. Over the decades there has been tremendous advances both in design (compact, multifunctional, tele-consult capable) and technology (wide- and ultra-wide field and noninvasive retinal angiography). These new advances have application in most of the pediatric retinal diseases though at most times the designs of new devices have remained confined to use in adults. Poor patient cooperation and insufficient attention span in children demand careful crafting of the devices. The newer attempts of hand-held retinal diagnostic devices are welcome additions in this direction. While much has been done, there is still much to do in the coming years. One of the compelling and immediate needs is the pediatric version of optical coherence tomography angiography. These needs and demands would increase many folds in future. A sound policy could be the simultaneous development of adult and pediatric version of all ophthalmic diagnostic devices, coupled with capacity building of trained medical personnel.

Foveal Differentiation and Inner Retinal Displacement Are Arrested in Extremely Premature Infants

Purpose

Children with a history of prematurity often have poorly developed foveae but when during development foveal differences arise. We hypothesize that the course of foveal development is altered from the time of preterm birth.

Methods

Eyes of 102 preterm infants undergoing retinopathy of prematurity screening examinations in the STudy of Eye imaging in Premature infantS (BabySTEPS) (NCT02887157) were serially imaged between 30 and 42 weeks postmenstrual age (PMA) using handheld optical coherence tomography systems. Total retinal thickness, inner retinal layer (IRL) thickness, and outer retinal layer (ORL) thickness were measured at the foveal center and parafovea. Foveal put depth, IRL thickness, and ORL thickness were compared between infants born at different gestational ages using mixed effects models.

Results

Foveal pit depth and IRL thickness were inversely related to gestational age; on average, the most premature infants had the thickest IRL and shallowest pits at all PMAs. Differences were evident by 30 weeks PMA and persisted through 42 weeks PMA. The foveal pits of the most premature infants did not progressively deepen, and the IRLs did not continue to thin with increasing chronological age.

Conclusions

Foveation in extremely preterm infants is arrested from the earliest observed ages and fails to progress through term equivalent age. The developmental displacement of the IRL from the foveal center into the parafovea does not occur normally after preterm birth. These observations suggest that foveal hypoplasia seen in children with history of prematurity is due to disturbances in foveal development that manifest within weeks of birth.

Risdiplam treatment has not led to retinal toxicity in patients with spinal muscular atrophy

OBJECTIVE

Evaluation of ophthalmologic safety with focus on retinal safety in patients with spinal muscular atrophy (SMA) treated with risdiplam (EVRYSDI®), a survival of motor neuron 2 splicing modifier associated with retinal toxicity in monkeys. Risdiplam was approved recently for the treatment of patients with SMA, aged ≥ 2 months in the United States, and is currently under Health Authority review in the EU.

METHODS

Subjects included patients with SMA aged 2 months-60 years enrolled in the FIREFISH, SUNFISH, and JEWELFISH clinical trials for risdiplam. Ophthalmologic assessments, including functional assessments (age-appropriate visual acuity and visual field) and imaging (spectral domain optical coherence tomography [SD-OCT], fundus photography, and fundus autofluorescence [FAF]), were conducted at baseline and every 2-6 months depending on study and assessment. SD-OCT, FAF, fundus photography, and threshold perimetry were evaluated by an independent, masked reading center. Adverse events (AEs) were reported throughout the study.

RESULTS

A total of 245 patients receiving risdiplam were assessed. Comprehensive, high-quality, ophthalmologic monitoring assessing retinal structure and visual function showed no retinal structural or functional changes. In the youngest patients, SD-OCT findings of normal retinal maturation were observed. AEs involving eye disorders were not suggestive of risdiplam-induced toxicity and resolved with ongoing treatment.

INTERPRETATION

Extensive ophthalmologic monitoring conducted in studies in patients with SMA confirmed that risdiplam does not induce ophthalmologic toxicity in pediatric or adult patients with SMA at the therapeutic dose. These results suggest that safety ophthalmologic monitoring is not needed in patients receiving risdiplam, as also reflected in the United States Prescribing Information for risdiplam.

VISUAL FUNCTION AND OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY FEATURES IN CHILDREN BORN PRETERM

PURPOSE

Preterm children have an increased risk of impaired vision from retinopathy, strabismus, and high refractive error. The aim of this study was to investigate the relationship between foveal parameters generated by optical coherence tomography angiography and visual function in preterm children.

METHODS

Eighty eyes (32 eyes of former preterm infants and 48 age-matched full-term control eyes) were analyzed. Subjects underwent complete eye examinations including best-corrected visual acuity and retinal imaging with the Optovue XR Avanti optical coherence tomography angiography device. Foveal morphologic parameters including foveal depth, central foveal thickness, inner retinal area, and outer retinal area were measured on a central horizontal B-scan. Foveal vasculature parameters including foveal avascular zone, superficial capillary plexus-vessel density, and deep capillary plexus-vessel density were measured on optical coherence tomography angiography.

RESULTS

The best-corrected visual acuity was significantly affected in preterm children compared with controls (P < 0.0001). The central foveal thickness (P < 0.0001), inner retinal area (P = 0.01), and outer retinal area (P = 0.03) were significantly increased in preterm compared with control eyes. Foveal depth (P < 0.001) and foveal avascular zone (P < 0.001) were significantly decreased in preterm compared with control eyes. The superficial capillary plexus-vessel density (P = 0.01) and deep capillary plexus-vessel density (P = 0.003) at the fovea (1 mm) were significantly increased in preterm compared with control eyes. The best-corrected visual acuity was negatively correlated with foveal depth (r = -0.42, P = 0.001) and foveal avascular zone (r = -0.53, P < 0.001), and positively correlated with central foveal thickness (r = 0.32, P = 0.01) and inner retinal area (r = 0.32, P = 0.01), indicating that worse visual acuity was associated with a smaller foveal avascular zone, shallower foveal depth, increased central foveal thickness, and larger inner retinal area.

CONCLUSION

Foveal morphology and vasculature changes in preterm children were associated with impaired visual function. Further longitudinal studies are required to evaluate these changes over time.

Understanding the variability of handheld spectral-domain optical coherence tomography measurements in supine infants

Purpose

Central foveal thickness (CFT) measurements from optical coherence tomography (OCT) scans provide a precise measure of severity of pathologic changes in the fovea, progress of disease and response to treatment. Although these measures are additionally valuable to assess foveal development in infants, their reproducibility is not known. The goal of this retrospective study is to evaluate the variation and reproducibility of CFT measurements using handheld spectral-domain OCT (hh-SDOCT) in supine infants compared to conventional adult tabletop imaging.

Methods

Imaging sessions with multiple macular, volume scans in one eye were selected for analysis from two participant groups: Group 1, 25 imaging sessions from 21 preterm infants without macular edema imaged supine in the nursery using hh-SDOCT (Leica/Bioptigen Envisu C2300, RTP, NC); Group 2, 25 imaging sessions from 25 adults imaged using tabletop Bioptigen SDOCT. For each imaging session, three macular OCT volumes with acceptable image quality were selected for analysis. CFTs were measured using a customized script for automatic segmentation. An expert grader and a typical grader corrected the segmentation lines for the central foveal frame. Coefficient of variations (CV) and intraclass correlation coefficients (ICC) were calculated for graders and systems and compared to the previous literature on OCT reproducibility.

Results

CFT measurements were repeatable and reproducible for both handheld and tabletop SDOCT systems. For handheld, grader ICC (CI) and mean CV were 0.94 (0.90–0.97) and 3.8 (typical) and 0.98 (0.96–0.99) and 2.9 (expert), and for tabletop were 0.91(0.83–0.96) and 2.1 (typical) and 0.92 (0.86–0.96) and 1.9 (expert). Intergrader reproducibility of handheld and tabletop SDOCT systems were ICC(CI) 0.97 (0.95–0.98) and 0.93 (0.89–0.96) respectively, and both are comparable to previously reported reproducibility of tabletop systems.

Conclusion

Handheld SDOCT is a reproducible instrument to measure foveal thicknesses in supine infants. It can be used in clinical research to evaluate foveal changes during retinal development and pathological conditions.

Handheld Optical Coherence Tomography Normative Inner Retinal Layer Measurements for Children <5 Years of Age

PURPOSE

Measurements of the ganglion cell complex (GCC), comprising the retinal nerve fiber (RNFL), ganglion cell, and inner plexiform layers, can be correlated with vision loss caused by optic nerve disease. Handheld optical coherence tomography (HH-OCT) can be used with sedation in children who are not amenable to traditional imaging. We report GCC and RNFL measurements in normal children using HH-OCT.

DESIGN

Prospective observational study of normal children ≤5 years of age.

METHODS

Healthy, full-term children ≤5 years of age undergoing sedation or anesthesia were enrolled. Exclusion criteria included prematurity and pre-existing neurologic, genetic, metabolic, or intraocular pathology. Demographic data, axial length (Master-Vu Sonomed Escalon, Lake Success, New York, USA), and HH-OCT macular and optic nerve volume scans at 0° (Bioptigen, Inc., Morrisville, North Carolina, USA) were obtained. Retinal segmentation was completed with DOCTRAP software, creating average volume thickness maps.

RESULTS

Sixty-seven children (67 eyes, 31 males ranging in age from 3.4-70.9 months) were enrolled. Average axial length was 21.2 ± 1.0 mm with mean spherical equivalent +1.49 ± 1.34 diopters (range -2.25 to 4.25). Average GCC volume for the total retina was 0.28 ± 0.04 mm³. Forty-seven of these eyes had RNFL analysis. Average RNFL thickness of the papillomacular bundle was 38.2 ± 9.5 μm. There was no correlation between GCC volume, RNFL thickness, patient age, or axial length.

CONCLUSION

Average GCC volume and RNFL thickness was stable from 6 months to 5 years of age. This study provides normative data for GCC and RNFL obtained by HH-OCT in healthy eyes of young children, to serve in evaluating those with optic neuropathies.

The safety and effectiveness of 0.16 mg bevacizumab plus or minus additional laser photocoagulation in the treatment of retinopathy of prematurity

Purpose

Retinopathy of prematurity (ROP) is the leading cause of preventable blindness in premature infants. Antivascular endothelial growth factor (anti-VEGF) therapy has been used increasingly in treatment as a pharmacological alternative to laser therapy. In this study, we evaluate the results of low-dose anti-VEGF treatments.

Methods

Design: Retrospective--observational study. Infants who had been evaluated for ROP disease between February 2016 and February 2017 were assessed. We retrospectively reviewed the ROP stages, treatment results, and complications. Laser photocoagulation (LPC) and intravitreal bevacizumab (0.16 mg IVB) were used for treatment and fundus fluorescein angiography (FFA) was also performed in some of the cases.

Results

IVB was applied to 43 infants. A macular hole was seen in one infant's eye after IVB. LPC was applied to avascular areas in 21 infants. In three patients, persistence of the disease was observed after administration of a low dose of IVB. Additional LFK was performed in these patients. None of the infants who received LPC had any complications.

Conclusion

IVB is increasingly becoming the first-line treatment for ROP. For severe ROP, 0.16 mg IVB is effective. Using LPC to treat avascular areas after 70 weeks' gestational age (GA) may decrease the risk of late recurrence and appears to be a safe treatment to use.

A computer-aided diagnosis system for plus disease in retinopathy of prematurity with structure adaptive segmentation and vessel based features

Retinopathy of Prematurity (ROP) is a blinding disease affecting the retina of low birth-weight preterm infants. Accurate diagnosis of ROP is essential to identify treatment-requiring ROP, which would help to prevent childhood blindness. Plus disease, which characterizes abnormal twisting, widening and branching of the blood vessels, is a significant symptom of treatment requiring ROP. In this paper, we have developed and evaluated a computer-based analysis system for objective assessment of plus disease in ROP, which best mimics the clinical method of disease diagnosis by identifying unique vessel based features. The proposed system consists of an initial segmentation stage, which will efficiently extract blood vessels of varying width and length by utilizing structure adaptive filtering, connectivity analysis and image fusion. The paper proposes the usage of additional retinal features namely leaf node count and vessel density, to portray the abnormal growth and branching of the blood vessels and to complement the commonly used features namely tortuosity and width. The test results show a better classification of plus disease in terms of sensitivity (95%) and specificity (93%), emphasizing the superiority of the proposed segmentation algorithm and vessel-based features. An additional advantage of the proposed system is that the process of selection of relevant vessels for feature extraction is fully automated, which makes the system highly useful to the non-physician graders, owing to the unavailability of a sufficient number of ROP specialists.

Optical coherence tomography in paediatric clinical practice

Optical coherence tomography is a non-invasive ocular imaging technique that is frequently used in the diagnosis and monitoring of optic nerve or retinal disease. Advances in optical coherence tomography speed and image processing capability allow increased use of the modality in clinical practice, especially in younger children. This review outlines the challenges involved in imaging children, highlights the technological progress, the importance of acquiring normative data and, finally, focuses on the clinical applicability of optical coherence tomography in our paediatric population with various ocular conditions.

Spectral Domain Optical Coherence Tomography in Detecting Sub-Clinical Retinal Findings in Asian Indian Children with Down Syndrome

Purpose: Trisomy 21, also known as Down syndrome (DS), is the most common trisomy worldwide. Although ocular associations have been reported, retinal anatomy and pathology remain uninvestigated. We evaluate the role of spectral domain optical coherence tomography (SD-OCT) in analyzing foveal morphology of children with DS. Methods: Nineteen consecutive DS children and eight controls were enrolled under a cross-sectional study in an institutional practice. All subjects underwent SD-OCT imaging on a hand-held device. The morphology and thickness of central fovea, inner retinal layers, outer retina, and photoreceptor layers were measured and compared with age-group sub-analysis. Results: Mean age of the cases was 24 months (3-78 months). All cases and controls had a normal fundus on ophthalmoscopy and foveal thickness was comparable (p = 0.718). Inner retinal fusion was complete in the foveal center in only three eyes (15.8%) of cases compared to all eyes (100%) of controls (p < 0.001). The outer plexiform layer was normal in 10 eyes of cases (52.6%) compared to all eyes (100%) of the controls. Only 10 eyes of DS (52.6%) had a normal external limiting membrane, compared to all eyes of controls (100%, p = 0.01). The interdigitation zone (outer segment) was normal in one (5.3%) case compared to eight (67%) controls (p = 0.001). On subgroup analysis, in older cohorts, cases had a greater proportion of abnormal layers compared to controls. Visual acuity was found to be lower in cases when compared to controls, although not significant (p = 0.19). Conclusion: DS babies have abnormal foveal morphology and persistence of inner retinal layers. This may assist our understanding of their visual development.

The Henle Fiber Layer in Albinism: Comparison to Normal and Relationship to Outer Nuclear Layer Thickness and Foveal Cone Density

Purpose

Directional optical coherence tomography (D-OCT) allows the visualization of the Henle fiber layer (HFL) in vivo. Here, we used D-OCT to characterize the HFL and outer nuclear layer (ONL) in albinism and examine the relationship between true foveal ONL and peak cone density.

Methods

Horizontal D-OCT B-scans were acquired, registered, and averaged for 12 subjects with oculocutaneous albinism and 26 control subjects. Averaged images were manually segmented to extract HFL and ONL thickness. Adaptive optics scanning light ophthalmoscopy was used to acquire images of the foveal cone mosaic in 10 subjects with albinism, from which peak cone density was assessed.

Results

Across the foveal region, the HFL topography was different between subjects with albinism and normal controls. In particular, foveal HFL thickness was thicker in albinism than in normal controls (P < 0.0001), whereas foveal ONL thickness was thinner in albinism than in normal controls (P < 0.0001). The total HFL and ONL thickness was not significantly different between albinism and controls (P = 0.3169). Foveal ONL thickness was positively correlated with peak cone density in subjects with albinism (r = 0.8061, P = 0.0072).

Conclusions

Foveal HFL and ONL topography are significantly altered in albinism relative to normal controls. Our data suggest that increased foveal cone packing drives the formation of Henle fibers, more so than the lateral displacement of inner retinal neurons (which is reduced in albinism). The ability to quantify foveal ONL and HFL may help further stratify grading schemes used to assess foveal hypoplasia.

A Prospective OCT Study of Rubella Retinopathy

PURPOSE

To analyze rubella retinopathy qualitatively and quantitatively in children diagnosed with congenital rubella syndrome (CRS) using a handheld spectral-domain (SD) OCT device.

DESIGN

Prospective, cross-sectional, nonrandomized, comparative observational study in a tertiary eye care center in south India.

PARTICIPANTS

Cases comprised 24 eyes of 13 children diagnosed with CRS based on seropositivity with rubella retinopathy. Controls comprised 26 eyes of 13 age-matched healthy children with normal retina.

METHODS

All participants underwent retinal imaging with RetCam fundus photography (Natus Medical Inc, Pleasanton, CA) and handheld SD OCT (Bioptigen, Inc., Durham, NC). The SD OCT images of both cases and controls were segmented. Retinal and choroid thickness parameters were computed.

MAIN OUTCOME MEASURES

Qualitative and quantitative changes were observed in SD OCT images of rubella retinopathy compared with those from controls.

RESULTS

Characteristic salt-and-pepper appearance was observed on fundus photography in children with rubella compared with the healthy children. The appearance of fovea and retinal features such as foveal dip, external limiting membrane, inner segment-outer segment boundary, outer segment-retinal pigment epithelium boundary, and retinal pigment epithelium were significantly different (P < 0.05) in eyes with rubella retinopathy compared with healthy eyes Furthermore, eyes with rubella retinopathy exhibited significantly reduced central foveal thickness (P = 0.025), subfoveal outer retinal thickness (P = 0.01), and subfoveal choroid thickness (P = 0.007) compared with healthy eyes.

CONCLUSIONS

Distinct qualitative and quantitative differences were observed in the SD OCT images of eyes with rubella retinopathy compared with those from healthy eyes.

Optical Detection of Macular Pigment Formation in Premature Infants

Purpose

To demonstrate the presence of macular pigment in the retina of premature infants, and to examine its changes with age.

Methods

The participants included 40 premature infants. Infants who had received laser photocoagulation for retinopathy of prematurity were excluded. Macular pigment optical density (MPOD) was measured by fundus reflectometry using RetCam3, a digital fundus camera. The reflection imaging was performed for ROP screening. The imaging time points were from a post menstrual age (PMA) of 29 weeks 0 days to 46 weeks 5 days.

Results

The MPOD levels could be obtained from 39 premature infants. The levels at the first measurement ranged from 0 to 0.18 (mean 0.076, SD 0.044). The earliest time, when a nonvanishing MPOD level was obtained, was at a PMA of 33 weeks and 2 days, and that level was 0.05. The initial examination MPOD levels showed a moderate correlation with age (R² = 0.32, P < 0.00017). The mean MPOD levels measured each week during the follow-up period showed a very strong correlation with age (R² = 0.91, P < 0.0001). A regression line of MPOD = 0.0069 × age − 0.1783 was derived, where age is counted in PMA days.

Conclusions

The MPOD levels of premature infants were for the first time measured in living eyes. Macular pigment increased linearly with age.

Translational Relevance

Macular pigment increased with the development of macular morphology. This result suggested the importance of nutritional management of infants and mothers during perinatal period.

Clinical relevance of retinal structure in children with laser-treated retinopathy of prematurity versus controls - using optical coherence tomography

PURPOSE

We aimed to assess the macular anatomy using spectral domain optical coherence tomography (SD-OCT), in children born preterm who had laser-treated retinopathy of prematurity (ROP), and to investigate the relationship between structural changes in macula and visual function.

METHODS

Thirty-seven 3-8 years old children were included in the study in two groups: 20 children born preterm [(<34 weeks of gestation, birthweight (BW) <2000 g)] who had laser-treated ROP in the Neonatology Department, Municipal Clinical Emergency Hospital of Timisoara, Romania; and 17 controls (children born at term, without eye disease, matched for age and gender). Spectral domain optical coherence tomography (SD-OCT) imaging (Spectralis OCT) was performed at central fovea and 1 mm nasally.

RESULTS

In the ROP group (total 34 eyes), we included both eyes in 14 children, and on one eye in six other children. In the control group, both eyes for all 17 children were included. Central fovea thickness (CFT) was significantly higher in children born preterm and with laser-treated ROP as compared to controls (275 ± 34.8 μm versus 224 ± 27.2 μm; p < 0.001). The laser-treated eyes with ROP had mean best-corrected visual acuity (BCVA) = 0.19 logMAR (20/31 Snellen); 35% had BCVA ≥0.3 logMAR (20/40 Snellen). In receiver operating characteristic curve (ROC) analysis, with BCVA as static variable (category 0 = BCVA ≤0.3 logMAR), the CFT cut-off was 257 μm (sensitivity: 0.917; specificity: 0.661; area under the curve: 0.810, p = 0.001).

CONCLUSION

Years after the laser intervention, central fovea was significantly thicker in ROP laser-treated children born preterm when compared to controls. Central fovea thickness (CFT) correlated strongly and inversely with BW and gestational age (GA) at birth, while a CFT value above 257 μm was suggestive for suboptimal visual acuity. The proposed cut-off value needs to be validated in future larger studies.

OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY OF THE FOVEA IN CHILDREN BORN PRETERM

PURPOSE

To compare the foveal avascular zone (FAZ) area measured by optical coherence tomography angiography in children who had been born preterm with age-matched controls.

METHODS

In this cross-sectional observational comparative case series, 43 eyes of 26 children (28 eyes of 15 former preterm infants and 15 eyes of 11 former term infants) between the ages of 4 and 12 years old were included. Optical coherence tomography angiography with a scan size of 3 × 3 was performed for all eyes. Foveal avascular zone area was measured using the Optovue RTVue AVANTI instrument (Optovue Inc, Fremont, CA) software. Inner and outer retinal thicknesses were measured with the instrument caliper.

RESULTS

A distinct FAZ was absent in 12 eyes (42.8%) of children with a history of preterm birth, however, it was present in all (100%) control eyes. The FAZ area was significantly correlated with gestational age (r = 0.82, P < 0.001) and birth weight (r = 0.80, P < 0.001). The gestational age was less than 29 weeks and birth weight was less than 1,480 grams in eyes with no distinct FAZ. Mean central foveal vessel density in the superficial capillary plexus was 41.8 ± 4.4% in the preterm group and 32.8 ± 5.8% in the control group (P < 0.001). In all eyes, a significant negative correlation was found between the central foveal vessel density and gestational age (r = -0.63, P = 0.001) and birth weight (r = -0.59, P = 0.002). On spectral domain optical coherence tomography examination, the foveal depression was absent and the inner retinal layers were preserved in all eyes with absent FAZ. In all eyes, a significant negative correlation was found between the inner retinal thickness and gestational age (r = -0.68, P < 0.001) and birth weight (r = -0.61, P = 0.001). Ten eyes of 6 preterm children had a history of laser therapy for retinopathy of prematurity. A distinct FAZ was absent in six eyes (60%) with retinopathy of prematurity with history of laser therapy, and six eyes (33.3%) with preterm birth without laser therapy. Eyes with history of laser therapy had a statistically significantly higher inner retinal thickness and central foveal vessel density and smaller FAZ compared with the eyes with preterm birth without laser therapy (P < 0.001, P = 0.04 and P = 0.03, respectively).

CONCLUSION

Optical coherence tomography angiography is a novel modality for noninvasive visualization of the retinal vasculature in pediatric patients and expands our knowledge of foveal abnormalities in retinopathy of prematurity. A small or absent FAZ seems to be a distinct sign of prematurity.

Foveal Development in Infants Treated with Bevacizumab or Laser Photocoagulation for Retinopathy of Prematurity

PURPOSE

To characterize and quantify early foveal development in preterm infants and to compare this development between eyes treated with intravitreal bevacizumab or laser photocoagulation (LPC) and untreated eyes.

DESIGN

Observational case series.

PARTICIPANTS

One hundred thirty-one preterm infants undergoing retinopathy of prematurity (ROP) screenings.

METHODS

Handheld OCT imaging was performed longitudinally on all patients. Thickness measurements of the inner and outer retinal layers were obtained at the foveal center and the nasal and temporal foveal rims. Comparisons between treated and untreated eyes were adjusted for age and other confounding variables.

MAIN OUTCOME MEASURES

Weekly change in inner and outer retinal thickness and presence of inner retinal layers, ellipsoid zone (EZ), and cystoid macular changes (CMCs).

RESULTS

Outer retinal thickness at the foveal center increased by 3.1 μm/week in untreated eyes and 7.2 μm/week in bevacizumab-treated eyes (P = 0.038). Eyes treated with LPC had a lower probability of having all inner retinal layers present at the foveal center (odds ratio, 0.04; P = 0.001) and a lower probability of having the EZ present at the foveal center (odds ratio, 0.07; P = 0.024) compared with untreated eyes. Cystoid macular changes were found in 53% of patients and 22% of imaging sessions. The age-adjusted incidence of CMCs was not correlated with bevacizumab or LPC treatment.

CONCLUSIONS

Intravitreal bevacizumab therapy for ROP is associated with more rapid outer retinal thickening at the foveal center, whereas LPC is associated with earlier extrusion of the inner retinal layers and delayed development of the EZ at the foveal center. Long-term follow-up is needed to determine the visual significance of these findings.

Characterization of Long Working Distance Optical Coherence Tomography for Imaging of Pediatric Retinal Pathology

PURPOSE

We determined the feasibility of fovea and optic nerve head imaging with a long working distance (LWD) swept source optical coherence tomography (OCT) prototype in adults, teenagers, and young children.

METHODS

A prototype swept source OCT system with a LWD (defined as distance from the last optical element of the imaging system to the eye) of 350 mm with custom fixation targets was developed to facilitate imaging of children. Imaging was performed in 49 participants from three age groups: 26 adults, 16 children 13 to 18 years old (teenagers), and seven children under 6 years old (young children) under an approved institutional review board protocol. The imaging goal was to acquire high quality scans of the fovea and optic nerve in each eye in the shortest time possible. OCT B-scans and volumes of the fovea and optic nerve head of each eligible eye were captured and graded based on four categories (lateral and axial centration, contrast, and resolution) and on ability to determine presence or absence of pathology.

RESULTS

LWD-OCT imaging was successful in 88 of 94 eligible eyes, including seven of 10 eyes of young children. Of the successfully acquired OCT images, 83% of B-scan and volumetric images, including 86% from young children, were graded as high-quality scans. Pathology was observed in high-quality OCT images.

CONCLUSIONS

The prototype LWD-OCT system achieved high quality retinal imaging of adults, teenagers, and some young children with and without pathology with reasonable alignment time.

TRANSLATIONAL RELEVANCE

The LWD-OCT system can facilitate imaging in children.

Pathophysiology, screening and treatment of ROP: A multi-disciplinary perspective

The population of infants at risk for retinopathy of prematurity (ROP) varies by world region; in countries with well developed neonatal intensive care services, the highest risk infants are those born at less than 28 weeks gestational age (GA) and less than 1 kg at birth, while, in regions where many aspects of neonatal intensive and ophthalmological care are not routinely available, more mature infants up to 2000 g at birth and 37 weeks GA are also at risk for severe ROP. Treatment options for both groups of patients include standard retinal laser photocoagulation or, more recently, intravitreal anti-VEGF drugs. In addition to detection and treatment of ROP, this review highlights new opportunities created by telemedicine, where screening and diagnosis of ROP in remote locations can be undertaken by non-ophthalmologists using digital fundus cameras. The ophthalmological care of the ROP infant is undertaken in the wider context of neonatal care and general wellbeing of the infant. Because of this context, this review takes a multi-disciplinary perspective with contributions from retinal vascular biologists, pediatric ophthalmologists, an epidemiologist and a neonatologist. This review highlights the latest insights regarding cellular and molecular mechanisms in the formation of the retinal vasculature in the human infant, pathogenesis of ROP, detection and treatment of severe ROP, the risks and benefits of anti-VEGF therapy, the identification of new therapies over the horizon, and the optimal neonatal care regimen for best ROP outcomes, and the benefits and pitfalls of telemedicine in the remote screening and diagnosis of ROP, all of which have the potential to improve ROP outcomes.

Handheld Optical Coherence Tomography Angiography and Ultra-Wide-Field Optical Coherence Tomography in Retinopathy of Prematurity

Importance

Retinopathy of prematurity (ROP) is a leading cause of childhood blindness worldwide. Optical coherence tomography (OCT) has improved the care of adults with vitreoretinal disease, and OCT angiography (OCTA) is demonstrating promise as a technique to visualize the retinal vasculature with lower risk and cost than fluorescein angiography. However, to date, there are no commercially available devices able to obtain ultra-wide-field OCT or OCTA images in neonates.

Objective

To obtain ultra-wide-field OCT and OCTA images in neonates with ROP using a prototype handheld OCT and OCTA device.

Design, Setting, and Participants

This observational case series was conducted from March 1 to April 1, 2017, in an academic medical center among 4 neonates with ROP in the neonatal intensive care unit and in the operating room.

Main Outcomes and Measures

Acquisition of wide-field OCT and OCTA images using a handheld prototype OCTA and ultra-wide-field OCT device.

Results

Images were obtained from 4 neonates (1 girl and 3 boys; mean age, 38 weeks' postmenstrual age [range, 34-43 weeks]) with various stages of ROP: 3 in the neonatal intensive care unit and 1 in the operating room. The system can obtain noncontact en face OCT images and horizontal line scans with an approximately 40° field of view and up to 100° (ultra-wide-field) using a contact lens-based approach in a single 2-second scan. In addition, 20° × 20° (approximately 4 × 4-mm) OCTA scans were obtained in patients with ROP in a single 2-second scan.

Conclusions and Relevance

Optical coherence tomography and OCTA are gaining popularity in pediatric retinal imaging. This study reports on OCTA and ultra-wide-field OCT images in 4 neonates with various stages of ROP that were obtained using a prototype handheld device. Additional studies will be needed to prove the clinical value of this technology.

Postnatal maturation of the fovea in Macaca mulatta using optical coherence tomography

Changes in the foveal anatomy during infancy are an important component in early development of spatial vision. The present longitudinal study in rhesus monkeys was undertaken to characterize the postnatal maturation of the fovea. Starting at four weeks after birth, the retinas of the left eyes of sixteen infant monkeys were imaged using spectral domain optical coherence tomography (SD OCT). Retinal scans were repeated every 30 days during the first year of life and every 60 days thereafter. Volume scans through the fovea were registered, scaled using a three surface schematic eye, and analyzed to measure foveal pit parameters. The individual layers of the retina were manually segmented and thicknesses were measured over a transverse distance of 1250 microns from the center of the foveal pit. Based on infrared scanning laser ophthalmoscope (IR SLO) images acquired with the SD OCT system, there were significant changes in the extent of the retina scanned as the eyes matured. Using a three-surface schematic eye, the length of each scan could be computed and was validated using image registration (R² = 0.88, slope = 1.003, p < 0.05). Over the first 18 months of life, the mean retinal thickness at the pit center had increased by 21.4% with a corresponding 20.3% decrease in pit depth. The major changes occurred within the first 120 days, but did not stabilize until a year after birth. In Macaca mulatta infants, the primary anatomical maturation of the fovea occurs within the first few months of life, as determined by longitudinal data from SD OCT measurements. The timelines for maturation of the fovea correspond well with the normal development of the lateral geniculate nucleus, cortical neurophysiology, and spatial resolution in monkeys.

Analysis of Discrepancy Between Diagnostic Clinical Examination Findings and Corresponding Evaluation of Digital Images in the Telemedicine Approaches to Evaluating Acute-Phase Retinopathy of Prematurity Study

Importance

As effective treatments for potentially blinding retinopathy of prematurity (ROP) have been introduced, the importance of consistency in findings has increased, especially with the shift toward retinal imaging in infants at risk of ROP.

Objective

To characterize discrepancies in findings of ROP between digital retinal image grading and examination results from the Telemedicine Approaches to Evaluating Acute-Phase Retinopathy of Prematurity study, conducted from May 2011 to October 2013.

Design, Setting, and Participants

A poststudy consensus review of images was conducted by 4 experts, who examined discrepancies in findings between image grades by trained nonphysician readers and physician examination results in infants with referral-warranted ROP (RW-ROP). Images were obtained from 13 North American neonatal intensive care units from eyes of infants with birth weights less than 1251 g. For discrepancy categories with more than 100 cases, 40 were randomly selected; in total, 188 image sets were reviewed.

Main Outcomes and Measures

Consensus evaluation of discrepant image and examination findings for RW-ROP components.

Results

Among 5350 image set pairs, there were 161 instances in which image grading did not detect RW-ROP noted on clinical examination (G-/E+) and 854 instances in which grading noted RW-ROP when the examination did not (G+/E-). Among the sample of G-/E+ cases, 18 of 32 reviews (56.3%) agreed with clinical examination findings that ROP was present in zone I and 18 of 40 (45.0%) agreed stage 3 ROP was present, but only 1 of 20 (5.0%) agreed plus disease was present. Among the sample of G+/E- cases, 36 of 40 reviews (90.0%) agreed with readers that zone I ROP was present, 23 of 40 (57.5%) agreed with readers that stage 3 ROP was present, and 4 of 16 (25.0%) agreed that plus disease was present. Based on the consensus review results of the sampled cases, we estimated that review would agree with clinical examination findings in 46.5% of the 161 G-/E+ cases (95% CI, 41.6-51.6) and agree with trained reader grading in 70.0% of the 854 G+/E- cases (95% CI, 67.3-72.8) for the presence of RW-ROP.

Conclusions and Relevance

This report highlights limitations and strengths of both the remote evaluation of fundus images and bedside clinical examination of infants at risk for ROP. These findings highlight the need for standardized approaches as ROP telemedicine becomes more widespread.

Foveal Layer Morphology Detected on Spectral Domain Optical Coherence Tomography and its Correlation with Visual Acuity in Asian Indian Premature Infants in their First Year of Life

PURPOSE

To report foveal microanatomy imaged on handheld spectral domain optical coherence tomography (SDOCT) and correlate it with visual acuity in Asian Indian premature infants.

METHODS

A retrospective analysis of 32 Asian Indian premature infants, 10 with Type 2 retinopathy of prematurity (ROP), were imaged between 3 and 12 months of corrected postmenstrual age (PMA) on the handheld SDOCT (Envisu 2300, Bioptigen, DNC, USA). The foveal findings on these images were correlated with visual acuity measured using Teller acuity cards. The study cohort was divided into three groups based on the corrected age, 3-<6 months, 6-<9 months, and 9-12 months. SDOCT images of the foveal center were analyzed for inner retinal layer (IRL) persistence or fusion and presence of the external limiting membrane (ELM), inner segment-outer segment or the ellipsoid zone (EZ), and the outer segment-retinal pigment epithelium (OS-RPE) layers.

RESULTS

The mean visual acuity of the three groups was 1.60, 1.63, and 1.23 logMAR, respectively (p < 0.001). Visual acuity significantly correlated with all four layers (IRL fusion, ELM, EZ, and OS-RPE in the 3-<6-month group [p < 0.001], IRL fusion only in 6-<9-month group (p < 0.001), and IRL fusion and EZ in the 9-12-month group (p < 0.001 and p = 0.01, respectively).

CONCLUSIONS

The study provides insights into our understanding of a premature infant's foveal maturation in the first year. Inner retinal fusion or maturation is the most important event that correlates with better visual acuity throughout the first year. In addition, between 9 and 12 months PMA, the completion of the EZ at the foveal center positively influenced visual acuity. The presence of ROP did not influence development of the layers, but the sample size was small for subgroup analysis.

A Case of Hydranencephaly in Which Ophthalmic Examinations Were Performed

Purpose

We performed ophthalmic examinations, including optical coherence tomography (OCT), on a case diagnosed with hydranencephaly.

Case Report

This case involved a female infant born at the gestational age of 35 weeks and 4 days, with the birth weight of 2,152 g, who was one of monochorionic diamniotic twins, and the identical twin died in utero at the gestational age of 24 weeks. After that, examination by fetal echo indicated that she had microcephaly and ventriculomegaly. Postnatal magnetic resonance imaging (MRI) of her head indicated microcephaly and significant enlargement of the lateral ventricle on both sides, with no obvious signs of elevated intracranial pressure. The brain parenchyma of both sides of the frontal lobe, parietal lobe, and occipital lobe had marked thinning, yet that of the temporal lobe, basal ganglia, thalamus, brain stem, and cerebellum had been maintained. Moreover, no obvious hematoma or neoplastic lesions were observed. Ophthalmic examinations indicated that both of her eyes had slight light reflex, attributed to optic nerve atrophy. Examination by use of a hand-held OCT system indicated a layered structure of the retina and thinning of the ganglion cell layer. Flicker electroretinogram (ERG) examination by use of a hand-held ERG system indicated an almost normal wave. However, no clear visual reaction was observed when she was 10 months old.

Conclusion

Our findings in this case of hydranencephaly revealed that even though the outer layer functions of the patient's retina were maintained, extensive damage to her cerebral cortex resulted in poor visual function.

Optical coherence tomography of the preterm eye: from retinopathy of prematurity to brain development

Preterm infants with retinopathy of prematurity are at increased risk of poor neurodevelopmental outcomes. Because the neurosensory retina is an extension of the central nervous system, anatomic abnormalities in the anterior visual pathway often relate to system and central nervous system health. We describe optical coherence tomography as 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. Optical coherence tomography has increased understanding of normal eye development and has identified several potential biomarkers of brain abnormalities and poorer neurodevelopment.