Severity of cystoid macular oedema in preterm infants observed using hand-held spectral domain optical coherence tomography improves weekly with postmenstrual age

Acknowledgements Staff Nurse Samantha Brown, the Department of Neonatology Staff and Parents of preterm infants, University Hospitals of Leicester NHS Trust, Leicester LE1 5WW. Funding Medical Research Council, London, UK (grant number: MR/N004566/1 and MR/J004189/1), Ulverscroft Foundation, Leicester, UK, Nystagmus Network UK.Peer reviewedPublisher PD

Phenotypic Features Determining Visual Acuity in Albinism and the Role of Amblyogenic Factors.

Albinism is a spectrum disorder causing foveal hypoplasia, nystagmus, and hypopigmentation of the iris and fundus along with other visual deficits, which can all impact vision. Albinism is also associated with amblyogenic factors which could affect monocular visual acuity. The foveal appearance in albinism can range from mild foveal hypoplasia to that which is indistinguishable from the peripheral retina. The appearance can be quickly and easily graded using the Leicester Grading System in the clinic. However, interquartile ranges of 0.3 logMAR for the grades associated with albinism limit the accuracy of the grading system in predicting vision. Here, we discuss the potential role of nystagmus presenting evidence that it may not be a major source of variability in the prediction of visual acuity. We also show that interocular differences in visual acuity are low in albinism despite high levels of amblyogenic factors indicating that active suppression of vision in one eye in albinism is uncommon

The Role of FRMD7 in Idiopathic Infantile Nystagmus

Idiopathic infantile nystagmus (IIN) is an inherited disorder in which the nystagmus arises independently of any other symptoms, leading to the speculation that the disorder represents a primary defect in the area of the brain responsible for ocular motor control. The inheritance patterns are heterogeneous, however the most common form is X-linked. FRMD7 resides at Xq26-27 and approximately 50% of X-linked IIN families map to this region. Currently 45 mutations within FRMD7 have been associated with IIN, confirming the importance of FRMD7 in the pathogenesis of the disease. Although mutations in FRMD7 are known to cause IIN, very little is known about the function of the protein. FRMD7 contains a conserved N-terminal FERM domain suggesting that it may provide a link between the plasma membrane and actin cytoskeleton. Limited studies together with the knowledge of the function of other FERM domain containing proteins, suggest that FRMD7 may play a role in membrane extension during neuronal development through remodeling of the actin cytoskeleton

Visual Field Deficits in Albinism in Comparison to Idiopathic Infantile Nystagmus.

PURPOSE: This is the first systematic comparison of visual field (VF) deficits in people with albinism (PwA) and idiopathic infantile nystagmus (PwIIN) using static perimetry. We also compare best-corrected visual acuity (BCVA) and optical coherence tomography measures of the fovea, parafovea, and circumpapillary retinal nerve fiber layer in PwA. METHODS: VF testing was performed on 62 PwA and 36 PwIIN using a Humphrey Field Analyzer (SITA FAST 24-2). Mean detection thresholds for each eye were calculated, along with quadrants and central measures. Retinal layers were manually segmented in the macular region. RESULTS: Mean detection thresholds were significantly lower than normative values for PwA (-3.10 ± 1.67 dB, P \u3c\u3c 0.0001) and PwIIN (-1.70 ± 1.54 dB, P \u3c 0.0001). Mean detection thresholds were significantly lower in PwA compared to PwIIN (P \u3c 0.0001) and significantly worse for left compared to right eyes in PwA (P = 0.0002) but not in PwIIN (P = 0.37). In PwA, the superior nasal VF was significantly worse than other quadrants (P \u3c 0.05). PwIIN appeared to show a mild relative arcuate scotoma. In PwA, central detection thresholds were correlated with foveal changes in the inner and outer retina. VF was strongly correlated to BCVA in both groups. CONCLUSIONS: Clear peripheral and central VF deficits exist in PwA and PwIIN, and static VF results need to be interpreted with caution clinically. Since PwA exhibit considerably lower detection thresholds compared to PwIIN, VF defects are unlikely to be due to nystagmus in PwA. In addition to horizontal VF asymmetry, PwA exhibit both vertical and interocular asymmetries, which needs further exploration

Potential Utility of Foveal Morphology in Preterm Infants Measured using Hand-Held Optical Coherence Tomography in Retinopathy of Prematurity Screening

Financial Support: Medical Research Council, London, UK (grant number: MR/N004566/1 and MR/J004189/1), Ulverscroft Foundation, Leicester, UK, Nystagmus Network UK. Acknowledgements: The authors acknowledge the assistance of Deputy Sister Hima Thanki in assisting with the acquisition of HH-OCT images and the Staff of the University Hospitals of Leicester Neonatal Service in supporting the infants during the imaging sessions.Peer reviewedPublisher PD

Feasibility and Clinical Utility of Hand-held Optical Coherence Tomography in Children with Retinoblastoma

This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023

The potential and value of objective eye tracking in the ophthalmology clinic

Numerous research studies have demonstrated the scope and value of eye movement recording (EMR). There is now potential for EMR to be helpful in a range of clinical contexts and it could be developed as a routine part of the repertoire of clinical investigations offered by the NHS, at least in tertiary centres. We highlight potential uses and challenges below, as a prelude to further development and debat

Electrophysiological and fundoscopic detection of intracranial hypertension in craniosynostosis

Aims: To assess the diagnostic accuracy of fundoscopy and visual evoked potentials (VEPs) in detecting intracranial hypertension (IH) in patients with craniosynostosis undergoing spring-assisted posterior vault expansion (sPVE). Methods: Children with craniosynostosis undergoing sPVE and 48-hour intracranial pressure (ICP) monitoring were included in this single-centre, retrospective, diagnostic accuracy study. Data for ICP, fundoscopy and VEPs were analysed. Primary outcome measures were papilloedema on fundoscopy, VEP assessments and IH, defined as mean ICP &gt; 20 mmHg. Diagnostic indices were calculated for fundoscopy and VEPs against IH. Secondary outcome measures included final visual outcomes. Results: Fundoscopic examinations were available for 35 children and isolated VEPs for 30 children, 22 of whom had at least three serial VEPs. Sensitivity was 32.1% for fundoscopy (95% confidence intervals [CI]: 15.9–52.4) and 58.3% for isolated VEPs (95% CI 36.6–77.9). Specificity for IH was 100% for fundoscopy (95% CI: 59.0–100) and 83.3% for isolated VEPs (95% CI: 35.9–99.6). Where longitudinal deterioration was suspected from some prVEPs but not corroborated by all, sensitivity increased to 70.6% (95% CI: 44.0–89.7), while specificity decreased to 60% (95% CI: 14.7–94.7). Where longitudinal deterioration was clinically significant, sensitivity decreased to 47.1% (23.0–72.2) and specificity increased to 100% (47.8–100). Median final BCVA was 0.24 logMAR (n = 36). UK driving standard BCVA was achieved by 26 patients (72.2%), defined as ≥0.30 logMAR in the better eye. Conclusion: Papilloedema present on fundoscopy reliably indicated IH, but its absence did not exclude IH. VEP testing boosted sensitivity at the expense of specificity, depending on method of analysis.</p

Cerebral malaria: insight into pathology from optical coherence tomography

AbstractWe aimed to investigate structural retinal changes in malarial retinopathy (MR) using hand-held optical coherence tomography (HH-OCT) to assess its diagnostic potential. Children with MR (n = 43) underwent ophthalmoscopy, fluorescein angiography and HH-OCT during admission, 1-month (n = 31) and 1-year (n = 8) post-discharge. Controls were comatose patients without malaria (n = 6) and age/sex-matched healthy children (n = 43). OCT changes and retinal layer thicknesses were compared. On HH-OCT, hyper-reflective areas (HRAs) were seen in the inner retina of 81% of MR patients, corresponding to ischaemic retinal whitening on fundus photography. Cotton wool spots were present in 37% and abnormal hyper-reflective dots, co-localized to capillary plexus, in 93%. Hyper-reflective vessel walls were present in 84%, and intra-retinal cysts in 9%. Vascular changes and cysts resolved within 48 h. HRAs developed into retinal thinning at 1 month (p = 0.027) which was more pronounced after 1 year (p = 0.009). Ischaemic retinal whitening is located within inner retinal layers, distinguishing it from cotton wool spots. Vascular hyper-reflectivity may represent the sequestration of parasitized erythrocytes in vessels, a key CM feature. The mechanisms of post-ischemic retinal atrophy and cerebral atrophy with cognitive impairment may be similar in CM survivors. HH-OCT has the potential for monitoring patients, treatment response and predicting neurological deficits.</jats:p