Modernizing the evaluation of infantile nystagmus: the role of handheld optical coherence tomography.

BACKGROUND: Infantile nystagmus syndrome can be associated with an afferent problem (anterior or posterior segment) or constitute an isolated idiopathic disorder. With a normal ophthalmic examination, current guidelines recommend electroretinography (ERG) rather than magnetic resonance (MRI) for preliminary workup. Given the limited use of optical coherence tomography (OCT) in preverbal children, the purpose of this study was to evaluate the role of handheld OCT (HH-OCT) in the initial diagnostic evaluation of infantile nystagmus. METHODS: In this cross-sectional case series, the medical records of all children with infantile nystagmus and HH-OCT imaging at the Duke Eye Center from August 2016 to July 2021 were retrospectively reviewed. Children with anterior segment disorders or obvious retina/optic nerve structural pathology, bilateral ophthalmoplegia, or Down syndrome were excluded. Two masked pediatric ophthalmologists graded HH-OCT images for optic nerve head and macular abnormalities. A neuro-ophthalmologist reviewed clinical findings of each patient's presenting visit and recommended appropriate testing (MRI vs ERG), initially without, and again with HH-OCT image review. RESULTS: A total of 39 cases were included, with mean presenting age of 1.3 years. Final diagnoses included retinal or foveal abnormalities (7), optic nerve pathology (13), idiopathic (10), or unknown (9). HH-OCT findings included optic nerve hypoplasia (1), optic nerve elevation (3), persistence of the inner layers at the fovea (9), thin ganglion cell layer (8), ellipsoid zone abnormality (3), and thin choroid (1). HH-OCT findings altered initial clinical-only management in 16 cases (41%), including avoiding MRI (5) and ERG (10) testing. CONCLUSIONS: Our results suggest that HH-OCT has the potential to augment and streamline the evaluation of infantile nystagmus.

Performance of VisuALL virtual reality visual field testing in healthy children.

BACKGROUND: Virtual reality field testing may provide an alternative to standard automated perimetry. This study evaluates a virtual reality game-based automated perimetry in a healthy pediatric population. METHODS: A prospective series of pediatric patients at one institution who performed VisuALL perimetry (Olleyes Inc, Summit, NJ) using a game-based algorithm. Participants were examined by an experienced pediatric optometrist or ophthalmologist, who confirmed that there was no evidence of ocular disease expected to affect visual fields. Testing was performed binocularly, with the child wearing their spectacle correction in place. Age, refractive error, test duration, false positives, and stereoacuity were evaluated for associations with performance on VisuALL, as defined by mean deviation (MD) and pattern standard deviation (PSD). RESULTS: A total of 191 eyes of 97 patients (54% female) were included, with a mean age of 11.9 ± 3.1 years. The average MD was -1.82 ± 3.5 dB, with a mean foveal sensitivity of 32.0 ± 4.7 dB. Fifty-nine eyes (30.9%) had MD < -2 dB. Better performance, as assessed by MD and PSD, was associated with shorter test duration (P < 0.001) and older age (P < 0.001). False positives (P = 0.442), wearing spectacles (P = 0.092), Titmus stereoacuity (P = 0.197), and refractive error (P = 0.120) did not appear to be associated with improved performance, adjusting for age as a covariate. CONCLUSIONS: VisuALL virtual reality field testing was well tolerated in this pediatric study cohort. Older age and shorter test duration were associated with better performance on field testing.

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

BACKGROUND: Handheld optical coherence tomography (HH-OCT) lacks integrated segmentation/analysis software. Optic neuropathies cause ganglion cell layer (GCL) thinning, with normal to thickened inner nuclear layer (INL), suggesting the potential value of estimating the GCL/INL ratio on single-line foveal HH-OCT scans. This study determines this ratio in macular scans from healthy eyes of young children using HH-OCT and overhead-mounted OCT. METHODS: Macular OCT scans were obtained using either HH-OCT or overhead-mounted Spectralis FLEX-OCT in children ages 0-5 years undergoing clinically indicated anesthesia/sedation. Exclusion criteria included gestational age <37 weeks, neurologic disease, amblyopia, ocular disease, or large refractive error (spherical equivalent beyond -3.00 D to +8.00 D). For HH-OCT, the GCL and INL were manually measured in pixels from single-line macular scans at the thickest point nasal and temporal to the fovea. For FLEX-OCT images, measurements were aided by automated software. RESULTS: HH-OCT was obtained on 38 eyes (38 children, mean age 2.4 ± 1.8 years) and FLEX-OCT on 56 eyes (56 children, mean age 2.3 ± 1.5 years). Mean nasal GCL/INL was 1.24 ± 0.18 (min/max = 0.92/1.75) for HH-OCT and 1.29 ± 0.18 (min/max = 0.96/1.66) for FLEX-OCT (P = 0.11). Mean temporal GCL/INL was 1.22 ± 0.24 (min/max = 0.66/1.70) for HH-OCT and 1.19 ± 0.16 (min/max = 0.86/1.47) for FLEX-OCT (P = 0.47). CONCLUSIONS: Mean normative GCL/INL ratios were approximately 1.2 at the thickest macular areas both nasal and temporal to the fovea, with either HH-OCT or FLEX-OCT in young children's eyes. These values may prove useful when HH-OCT is used to assess optic neuropathies, in which the GCL/INL ratio is expected to be decreased.

Biallelic variants in ribonuclease inhibitor (RNH1), an inflammasome modulator, are associated with a distinctive subtype of acute, necrotizing encephalopathy.

PURPOSE: Mendelian etiologies for acute encephalopathies in previously healthy children are poorly understood, with the exception of RAN binding protein 2 (RANBP2)-associated acute necrotizing encephalopathy subtype 1 (ANE1). We provide clinical, genetic, and neuroradiological evidence that biallelic variants in ribonuclease inhibitor (RNH1) confer susceptibility to a distinctive ANE subtype. METHODS: This study aimed to evaluate clinical data, neuroradiological studies, genomic sequencing, and protein immunoblotting results in 8 children from 4 families who experienced acute febrile encephalopathy. RESULTS: All 8 healthy children became acutely encephalopathic during a viral/febrile illness and received a variety of immune modulation treatments. Long-term outcomes varied from death to severe neurologic deficits to normal outcomes. The neuroradiological findings overlapped with ANE but had distinguishing features. All affected children had biallelic predicted damaging variants in RNH1: a subset that was studied had undetectable RNH1 protein. Incomplete penetrance of the RNH1 variants was evident in 1 family. CONCLUSION: Biallelic variants in RNH1 confer susceptibility to a subtype of ANE (ANE2) in previously healthy children. Intensive immunological treatments may alter outcomes. Genomic sequencing in children with unexplained acute febrile encephalopathy can detect underlying genetic etiologies, such as RNH1, and improve outcomes in the probands and at-risk siblings.

Optical Coherence Tomography Findings in Cherry-Red Spot: Implications for Understanding Pathophysiology and Visual Prognosis.

PURPOSE: To report optical coherence tomography (OCT) findings of cherry-red spots from Tay-Sachs and Niemann-Pick disease. METHODS: Consecutive patients with Tay-Sachs and Niemann-Pick disease evaluated by the pediatric transplant and cellular therapy team, for whom a handheld OCT scan was obtained, were included. Demographic information, clinical history, fundus photography, and OCT scans were reviewed. Two masked graders evaluated each of the scans. RESULTS: The study included 3 patients with Tay-Sachs disease (5, 8, and 14 months old) and 1 patient with Niemann-Pick disease (12 months old). All patients had bilateral cherry-red spots on fundus examination. In all patients with Tay-Sachs disease, handheld OCT revealed parafoveal ganglion cell layer (GCL) thickening, increased nerve fiber layer, and GCL reflectivity, and different levels of residual normal signal GCL. The patient with Niemann-Pick disease had similar parafoveal findings, but there was a thicker residual GCL. Sedated visual evoked potentials were unrecordable in all 4 patients despite 3 of them demonstrating normal visual behavior for age. Patients with good vision had relative sparing of the GCL on OCT. CONCLUSIONS: The cherry-red spots in lysosomal storage diseases appear as perifoveal thickening and hyperreflectivity of the GCL on OCT. In this case series, residual GCL with normal signal proved to be a better biomarker for visual function than visual evoked potentials and could be considered for future therapeutic trials. [J Pediatr Ophthalmol Strabismus. 2023;60(6):435-440.].

Use of Trametinib in Children and Young Adults With Progressive Low-grade Glioma and Glioneuronal Tumors.

Low-grade gliomas/glioneuronal tumors comprise one-third of all pediatric-type CNS tumors. These tumors are generally caused by activating mutations in the mitogen-activated protein kinase (MAPK) pathway. Targeted drugs, such as trametinib, have shown promise in other cancers and are being utilized in low-grade gliomas. A retrospective chart review was conducted to evaluate radiographic response, visual outcomes, tolerability, and durability of response in progressive circumscribed low-grade gliomas treated with trametinib. Eleven patients were treated with trametinib. The best radiographic response was 2/11 partial response, 3/11 minor response, 3/11 stable disease, and 3/13 progressive disease. In the patients with partial or minor response, the best response was seen after longer durations of therapy; 4 of 5 best responses occurred after at least 9 months of therapy with a median of 21 months. Patients with optic pathway tumors showed at least stable vision throughout treatment, with 3 having improved vision on treatment. Trametinib is effective and well-tolerated in patients with progressive low-grade glioma. Best responses were seen after a longer duration of therapy in those with a positive response. Patients with optic pathway lesions showed stable to improved vision while on treatment.

Rates of Visual Field Change in Eyes With Optic Disc Drusen.

BACKGROUND: Optic disc drusen (ODD) are calcified deposits in the prelaminar portion of the optic nerve head. Although often asymptomatic, these deposits can cause progressive visual field defects and vision loss. The purpose of this study was to evaluate rates of functional loss in eyes with ODD and to investigate risk factors associated with rates of visual field progression. METHODS: This was a retrospective cohort study including 65 eyes of 43 patients with ODD from the Duke Ophthalmic Registry. All eyes had at least 12 months of follow-up and at least 3 reliable standard automated perimetry (SAP) tests. Linear mixed models were used to estimate rates of SAP mean deviation (MD) loss over time. Univariable and multivariable models were used to assess the effect of clinical variables and intraocular pressure (IOP) on rates of change. RESULTS: Subjects were followed for an average of 7.6 ± 5.3 years. The mean rate of SAP MD change was -0.23 ± 0.26 dB/year, ranging from -1.19 to 0.13 dB/year. Fifty-seven eyes (87.7%) had slow progression (slower than -0.5 dB/year), 6 eyes (9.2%) had moderate progression (between -0.5 dB/year and -1 dB/year), and 2 eyes (3.1%) had fast progression (faster than -1 dB/year). In multivariable models, older age and worse SAP MD at baseline were significantly associated with faster rates of change. Mean IOP was not associated with faster rates of MD change in both univariable and multivariable analyses. CONCLUSIONS: Most eyes with ODD had slow rates of visual field loss over time. Age and baseline severity were significantly associated with faster rates of visual field loss.

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

PURPOSE: To report and characterize unexpected retinal findings identified by imaging with overhead-mounted optical coherence tomography (OCT) in 2 young children with infantile-onset glaucoma. METHODS: Children with glaucoma were imaged during clinically indicated examinations under anesthesia using overhead-mounted HRA+OCT Spectralis with Flex module (Flex-OCT, Heidelberg, Germany) from February 2017 through February 2022. Imagers prioritized scans of the peripapillary retinal nerve fiber layer (pRNFL), optic nerve head, and macula. Children imaged before age 2 years with images adequate for evaluation were included. Age at glaucoma diagnosis, glaucoma type, highest intraocular pressure (IOP), corneal diameter (CD), and axial length (AL) were recorded. RESULTS: A total of 41 children (71 eyes with glaucoma) were imaged before age 2 years. Macular imaging identified both inner and outer retinal thinning in 3 eyes of 2 young children (both eyes of a child with newborn primary congenital glaucoma (PCG) and 1 eye of a child with glaucoma following cataract surgery), which remained stable over time. These findings were present in 2 of 41 children (4.9%) and 3 of 71 eyes (4.2%) imaged with Flex-OCT. Neither highest IOP, CD, nor AL at imaging differentiated the 3 eyes with retinal changes from the larger group. CONCLUSIONS: Three eyes of 2 young children with refractory glaucoma of different etiologies and highly elevated IOP demonstrated areas of inner and outer retinal thinning, consistent with retinal injury from probable prior macular ischemia. Unexpected retinal pathology identified on Flex-OCT imaging in infantile-onset glaucomas highlights the need for continued study of the pathophysiology of this disease.

Escape from prism.

A 14-year-old boy with a history of shunted congenital hydrocephalus began having headaches with nausea and vomiting after transcontinental flights. He gradually developed horizontal diplopia indicative of mild bilateral sixth nerve palsy, without papilledema or ventriculomegaly. Intracranial pressure monitoring showed no signs of elevation. After he subsequently developed papilledema, surgical exploration showed shunt malfunction, and shunt replacement produced rapid resolution of symptoms. This case demonstrates the importance of relying on clinical history and neuro-ophthalmologic examination in patients with hydrocephalus and suspected shunt failure, even when objective confirmatory evidence of intracranial pressure elevation is lacking.

Associations between systemic health and retinal nerve fibre layer thickness in preterm infants at 36 weeks postmenstrual age.

BACKGROUND/AIMS: Neonatal insults from systemic diseases have been implicated in the pathway of impaired neurodevelopment in preterm infants. We aimed to investigate the associations between systemic health factors and retinal nerve fibre layer (RNFL) thickness in preterm infants. METHODS: We prospectively enrolled infants and imaged both eyes at 36±1 weeks postmenstrual age (PMA) using a hand-held optical coherence tomography system at the bedside in the Duke intensive care nurseries. We evaluated associations between RNFL thickness and 29 systemic health factors using univariable and multivariable regression models. RESULTS: 83 infants with RNFL thickness measures were included in this study. Based on the multivariable model, RNFL thickness was positively associated with infant weight at imaging and was negatively associated with sepsis/necrotising enterocolitis (NEC). RNFL thickness was 10.4 µm (95% CI -15.9 to -4.9) lower in infants with than without sepsis/NEC in the univariable analysis (p<0.001). This difference remained statistically significant after adjustment for confounding variables in various combinations (birth weight, birthweight percentile, gestational age, infant weight at imaging and growth velocity). A 250 g increase in infant weight at imaging was associated with a 3.1 µm (95% CI 2.1 to 4.2) increase in RNFL thickness in the univariable analysis (p<0.001). CONCLUSIONS: Low infant weight and sepsis/NEC were independently associated with thinner RNFL in preterm infants at 36 weeks PMA. To our knowledge, this study is the first to suggest that sepsis/NEC may affect retinal neurodevelopment. Future longitudinal studies are needed to investigate this relationship further.

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

BACKGROUND/AIMS: The optic nerve development during the critical postnatal weeks of preterm infants is unclear. We aimed to investigate the change of retinal nerve fibre layer (RNFL) in preterm infants. METHODS: We used an investigational handheld optical coherence tomography (OCT) system to serially image awake preterm infants between 30 and 60 weeks postmenstrual age (PMA) at the bedside. We assessed RNFL thickness in the papillomacular bundle and nasal macular ganglion cell layer+inner plexiform layer (GCL+IPL) thickness. We applied a segmented mixed model to analyse the change in the thickness of RNFL and GCL+IPL as a function of PMA. RESULTS: From 631 OCT imaging sessions of 101 infants (201 eyes), RNFL thickness followed a biphasic model between 30 and 60 weeks, with an estimated transition at 37.8 weeks PMA (95% CI: 37.0 to 38.6). RNFL thickness increased at 1.8 µm/week (95% CI: 1.6 to 2.1) before 37.8 weeks and decreased at -0.3 µm/week (95% CI: -0.5 to -0.2) afterwards. GCL+IPL thickness followed a similar biphasic model, in which the thickness increased at 2.9 µm/week (95% CI: 2.5 to 3.2) before 39.5 weeks PMA (95% CI: 38.8 to 40.1) and then decreased at -0.8 µm/week (95% CI: -0.9 to -0.6). CONCLUSION: We demonstrate the feasibility of monitoring RNFL and GCL+IPL thickness from OCT during the postnatal weeks of preterm infants. Thicknesses follow a biphasic model with a transition age at 37.8 and 39.5 weeks PMA, respectively. These findings may shed light on optic nerve development in preterm infants and assist future study designs.

Performance of virtual reality game-based automated perimetry in patients with childhood glaucoma.

PURPOSE: To evaluate VisuALL, a game-based automated perimetry device, utilizing virtual reality (VR) goggles, in a cohort of patients with childhood glaucoma. METHODS: In this prospective series, the results of consecutive patients with childhood glaucoma performing both VisuALL VR field (VRF) and Humphrey visual field (HVF) 24-2 testing were compared. A masked ophthalmologist graded both VRF and HVF tests for field defects (three clustered abnormal points in total or pattern deviation plot). VRF testing was performed binocularly and with the child's own spectacles. The two devices were assessed with respect to agreement of (1) global indices, such as mean deviation (MD) and pattern standard deviation (PSD), (2) point-by-point sensitivity, and (3) the ability to detect visual field defects determined by a grader. RESULTS: A total of 39 children (77 eyes) were enrolled, with mean age 14.1 ± 3.6 years; 3 patients (5 eyes) could not complete the HVF. Average HVF MD was -6.3 ± 6.4 dB. There was strong correlation between VRF and HVF for MD (R = 0.68, P < 0.001), PSD (R = 0.78, P < 0.001), and point-by-point sensitivity (R = 0.63, P < 0.001). Bland Altman analysis showed no systematic difference between VRF and HVF in assessing MD and PSD. Of 72 eyes having results for both modalities, 63 (87.5%) had agreement between VRF and HVF with respect to the presence/absence of any field defect, and 52 (72.2%) had agreement regarding the presence/absence of fixation-threatening field loss. CONCLUSIONS: VRF is comparable to the gold standard HVF in both identification and quantification of visual field deficits in pediatric glaucoma patients and may offer a valuable supplement or alternative to standard automated perimetry.

Intraoperative Mounted Optical Coherence Tomography Findings Following Reversal of Optic Nerve Head Cupping in Childhood Glaucoma.

PURPOSE: To examine the structural changes occurring in the optic nerve head (ONH) and macula in infants with childhood glaucoma and clinically observed ONH cupping reversal following intraocular pressure (IOP)-reducing glaucoma surgery, as captured by intra-operative spectral-domain optical coherence tomography (SD-OCT). DESIGN: Retrospective observational case series from an ongoing prospective cohort study. METHODS: Included were 18 eyes of 14 patients with childhood glaucoma. All eyes had SD-OCT imaging pre- and post-glaucoma intervention and clinically identified ONH cupping reversal. Patients with poor quality images or persistent optic nerve swelling following IOP reduction were excluded. Outcome measurements included IOP, cup-to-disc ratio, axial length and SD-OCT measurements of the peripapillary retinal nerve fiber layer (pRNFL), transverse horizontal diameter of Bruch membrane opening (BMO-D), cup depth, and macula. RESULTS: Mean age at surgery was 1.14±0.93 years and mean interval between pre- and post-operative imaging was 127 days (range 35-595). Following intervention, mean IOP reduction was 45%, accompanied by significant reductions in the cup-to-disc ratio (0.30±0.12, p<0.001), axial length (0.43±0.28mm, p<0.001) and cup depth (46%, p<0.001). Mean global pRNFL thickness pre- vs. post-treatment was 93.1±14.7µm vs. 93.1±17.1µm, respectively, p=1.0. There was no significant difference in pre- and post-treatment global or sectoral pRNFL, 3mm macular total and segmented retinal layer volumes, or the BMO-D. CONCLUSIONS: Clinical ONH cupping reversal after IOP-lowering surgery was associated with axial length reduction and decrease in cup depth, but no significant change in the pRNFL or macular volume measures. ONH cupping reversal likely marks stabilization but any pre-intervention ONH damage persists.

The microRNA processor DROSHA is a candidate gene for a severe progressive neurological disorder.

DROSHA encodes a ribonuclease that is a subunit of the Microprocessor complex and is involved in the first step of microRNA (miRNA) biogenesis. To date, DROSHA has not yet been associated with a Mendelian disease. Here, we describe two individuals with profound intellectual disability, epilepsy, white matter atrophy, microcephaly and dysmorphic features, who carry damaging de novo heterozygous variants in DROSHA. DROSHA is constrained for missense variants and moderately intolerant to loss-of-function (o/e = 0.24). The loss of the fruit fly ortholog drosha causes developmental arrest and death in third instar larvae, a severe reduction in brain size and loss of imaginal discs in the larva. Loss of drosha in eye clones causes small and rough eyes in adult flies. One of the identified DROSHA variants (p.Asp1219Gly) behaves as a strong loss-of-function allele in flies, while another variant (p.Arg1342Trp) is less damaging in our assays. In worms, a knock-in that mimics the p.Asp1219Gly variant at a worm equivalent residue causes loss of miRNA expression and heterochronicity, a phenotype characteristic of the loss of miRNA. Together, our data show that the DROSHA variants found in the individuals presented here are damaging based on functional studies in model organisms and likely underlie the severe phenotype involving the nervous system.

Acute Onset Variable and Progressive Trochlear Nerve Palsy and Ophthalmoparesis Secondary to Bilateral Carotid Cavernous Fistula.

Purpose: To describe a patient who presented with right unilateral white-eyed posteriorly-draining carotid-cavernous fistulas (CCF) causing an isolated, acute-onset trochlear nerve palsy with atypical progression to a contralateral left red-eyed anteriorly-draining CCF associated with orbital congestion.Observation: A 74-year-old female presented with an acute onset incomitant right hypertropia consistent with the clinical diagnosis of a superior oblique palsy. Initial workup including MRI was normal. During a several-week course, she progressed to a comitant deviation. Six-weeks later she developed an episode of severe headache followed by worsening of her diplopia, reverse left hypertropia and left orbital congestive signs. CTA revealed mild opacification of the left cavernous sinus without a concomitantly present superior ophthalmic vein dilatation. A diagnostic angiogram was obtained which revealed a posterior-draining indirect CCF of the right internal carotid artery (ICA) and an anterior-draining indirect CCF of the left ICA. Transvenous Coil embolization resulted in immediate resolution of diplopia, orbital congestion, and headaches.Conclusion: Although it is atypical for a CCF - or other vascular pathology - to present with an isolated fourth nerve palsy, this case illustrates that vascular imaging should be considered in cases of acquired ocular motor paresis associated with headaches and cases with atypical progression despite normal initial cranial imaging.

Magnetic Resonance Imaging Abnormalities of the Optic Nerve Sheath and Intracranial Internal Carotid Artery in Giant Cell Arteritis.

BACKGROUND: Giant cell arteritis (GCA) is an important diagnostic consideration in elderly patients with vision changes. Superficial temporal artery biopsy (TAB) has long been considered the gold standard diagnostic approach for GCA, but MRI has gained interest as an alternative diagnostic modality. Although most of the literature has focused on imaging abnormalities of branches of the external carotid artery, there have been a few reports of GCA-related inflammatory involvement of the orbit and internal carotid arteries (ICAs) on MRI. METHODS: This was a retrospective cross-sectional study of patients undergoing TAB at a single tertiary referral center over a 5-year period. Patients who had undergone contrast-enhanced MRI of the brain and orbits within 1 month of biopsy were included. Fifty-four TAB-positive and 78 TAB-negative patients were reviewed, with the MRI studies of 7 TAB-positive and 6 TAB-negative patients deemed adequate for interpretation. MRI studies were reviewed by 2 masked neuroradiologists, and the findings were correlated with biopsy results and clinical findings. RESULTS: Intracranial ICA vessel wall enhancement was identified in 6 of 7 TAB-positive patients (sensitivity 86%), compared with 2 of 6 TAB-negative patients (specificity 67%). Optic nerve sheath enhancement was identified in 5 of 7 TAB-positive patients (sensitivity 71%) and in 2 of 6 TAB-negative patients (specificity 67%), bilateral in all such cases. The combination of both abnormal imaging findings was observed in 5 of 7 TAB-positive patients (sensitivity 71%) and in none of the 6 TAB-negative patients (specificity 100%). CONCLUSIONS: Intracranial ICA and optic nerve sheath enhancement were observed in a majority of patients with TAB-proven GCA, and the combination of these findings was highly specific for GCA. Identification of these abnormalities on MRI should raise concern for GCA and prompt a thorough review of systems, laboratory testing, and consideration of TAB in patients with ocular complaints potentially consistent with ischemia.

QUANTITATIVE TOPOGRAPHIC CURVATURE MAPS OF THE POSTERIOR EYE UTILIZING OPTICAL COHERENCE TOMOGRAPHY.

PURPOSE: Deformations of the retina such as staphylomas in myopia or scleral flattening in high intracranial pressure can be challenging to quantify with en face imaging. We describe an optical coherence tomography-based method for the generation of quantitative posterior eye topography maps in normal and pathologic eyes. METHODS: Using "whole eye" optical coherence tomography, we corrected for subjects' optical distortions to generate spatially accurate posterior eye optical coherence tomography volumes and created local curvature (KM, mm-1) topography maps for each consented subject. We imaged nine subjects, three normal, two with myopic degeneration, and four with papilledema including one that was imaged longitudinally. RESULTS: Normal subjects mean temporal KM was 0.0923 mm-1, nasal KM was 0.0927 mm-1, and KM local variability was 0.0162 mm-1. In myopic degeneration, subjects KM local variability was higher at 0.0836 mm-1. In papilledema subjects nasal KM was flatter compared with temporal KM (0.0709 vs. 0.0885 mm-1). Mean intrasession KM repeatability for all subjects was 0.0036 mm-1. CONCLUSION: We have developed an optical coherence tomography based method for quantitative posterior eye topography that offers the ability to analyze local curvature with micron scale resolution and offers the potential to help clinicians and researchers characterize subtle, local retinal deformations earlier in patients and follow their development over time.