Ambient lighting alters pattern electroretinogram P50 peak time and spatial sensitivity.

Purpose: Our aim was to explore the effect of ambient lighting on the pattern ERG (PERG).

Methods: We compared PERGs recorded in two conditions; room lights on and room lights off. PERGs from 21 adult participants were recorded from each eye to high contrast checks of 50' side width, reversing 3rps in a large (30°) and then standard (15°) field.

Mapping degeneration of the visual system in long-term follow-up after childhood hemispherectomy - A series of four cases.

Objective: Although hemidisconnection surgery may eliminate or reduce seizure activity in patients with epilepsy, there are visual, cognitive and motor deficits which affect patients' function post-operatively, with varying severity and according to pathology. Consequently, there is a need to map microstructural changes over long time periods and develop/apply methods that work with legacy data.

Methods: In this study, we applied the novel single shell 3-Tissue method to data from a cohort of 4 patients who were scanned 20-years following childhood hemidisconnection surgery and presented with variable clinical outcomes.

Giant pattern VEPs in children.

Our aim is to elaborate the clinical significance of giant amplitude pattern reversal visual evoked potentials (VEPs) in children. 'Giant' amplitude VEPs exceed the upper 97.5 centile, 90% CI for age.

An ERG and OCT study of neuronal ceroid lipofuscinosis CLN2 Battens retinopathy.

Background: Late infantile neuronal ceroid lipofuscinosis (CLN2 Batten disease) is a rare, progressive neurodegenerative disease of childhood. The natural history of motor and language regression is used to monitor the efficacy of CNS treatments. Less is known about CLN2 retinopathy.

What can visual electrophysiology tell about possible visual-field defects in paediatric patients.

Recognising a potential visual-field (VF) defect in paediatric patients might be challenging, especially in children before the age of 5 years and those with developmental delay or intellectual disability. Visual electrophysiological testing is an objective and non-invasive technique for evaluation of visual function in paediatric patients, which can characterise the location of dysfunction and differentiate between disorders of the retina, optic nerve and visual pathway. The recording of electroretinography (ERG) and visual-evoked potentials (VEP) is possible from early days of life and requires no subjective input from the patient.

Enhanced neuro-ophthalmologic evaluation to support separation of craniopagus twins.

Craniopagus conjoined twins are extraordinarily rare and present unique challenges to the multidisciplinary team. There is a paucity of literature on optimizing neuro-ophthalmologic evaluation in craniopagus twins. Herein, we present our enhanced neuro-ophthalmologic evaluation and management in 17-month-old male craniopagus twins, uniquely using handheld optical coherence tomography (OCT) plus portable slit-lamp biomicroscopy, indirect ophthalmoscopy and modified forced-choice preferential looking assessment.

Case report: Unilateral optic nerve aplasia and developmental hemi-chiasmal dysplasia with VEP misrouting.

Purpose: To describe the trans-occipital asymmetries of pattern and flash visual evoked potentials (VEPs), in an infant with MRI findings of unilateral optic nerve aplasia and hemi-chiasm dysplasia.

Methods: A child with suspected left cystic microphthalmia, left microcornea, left unilateral optic nerve aplasia, and hemi-chiasm underwent a multi-channel VEP assessment with pattern reversal, pattern onset, and flash stimulation at the age of 16 weeks.

Results: There was no VEP evidence of any post-retinal visual pathway activation from left eye with optic nerve aplasia.

Pattern-onset and OFFset visual evoked potentials in the diagnosis of hemianopic field defects.

Background: Visual evoked potentials (VEPs) assess the function of the visual pathway from the retina to the primary visual cortex. There is much evidence that monocular pattern-reversal and flash VEPs can distinguish dysfunction due to chiasmal and post-chiasmal afferent pathway lesions. There is less evidence about the use of pattern-onset/OFFset VEPs to identify post-chiasmic dysfunction.

Misaligned foveal morphology and sector retinal dysfunction in AKT1-mosaic Proteus syndrome.

Purpose: Proteus syndrome arises as a result of a post-zygotic mosaic activating mutation in the AKT1 oncogene, causing a disproportionate overgrowth of affected tissues. A small number of ocular complications have been reported. We present the unique findings in a patient who had molecular confirmation of AKT1 mosaicism alongside fulfilling the clinical criteria for Proteus syndrome.

Microstructural Investigations of the Visual Pathways in Pediatric Epilepsy Neurosurgery: Insights From Multi-Shell Diffusion Magnetic Resonance Imaging.

Background: Surgery is a key approach for achieving seizure freedom in children with focal onset epilepsy. However, the resection can affect or be in the vicinity of the optic radiations. Multi-shell diffusion MRI and tractography can better characterize tissue structure and provide guidance to help minimize surgical related deficits.

Occipital Petalia and Albinism: A Study of Interhemispheric VEP Asymmetries in Albinism with No Nystagmus.

Unlabelled: The purpose of this study was to assess chiasmal misrouting in a cohort of children with albinism with no nystagmus using hemifield visual evoked potentials (VEP) measures.

Methods: Monocular VEPs were recorded and analyzed from three electrodes (O1, Oz, and O2 referred to Fz) from 16 children with albinism without nystagmus. Pattern reversal (full field and hemifield stimulation), full field pattern appearance and flash stimuli were used to evoke VEPs for each eye.

ERGs on the brain: the benefits of simultaneous flash retinal and cortical responses in paediatric cerebral visual impairment.

Purpose: To highlight the importance of simultaneous flash electroretinogram (ERG) and visual evoked potential (VEP) recording to differentiate a true flash VEP response from an artefact caused by the intrusion of the ERG on a mid-frontal reference electrode in cases of severe cerebral visual impairment (CVI).

Methods: We report an observational case series of four children with severe CVI who underwent simultaneous flash ERG and VEP recordings. Flash VEPs from Oz-Fz and lower lid skin ERGs referred to Fz were recorded simultaneously to Grass intensity setting 4 flash stimulation.

Trans-synaptic Retrograde Degeneration Following Hemispherectomy in Childhood.

Trans-synaptic retrograde degeneration (TRD) in the human visual system has been established. However there are few studies demonstrating macular thinning of the Retinal Ganglion cell Layer and/or Inner Plexiform layer (RGCL-IPL), corresponding to an acquired homonymous hemianopia. We report a 17 year old with a homonymous hemianopia, secondary to a hemispherectomy for intractable epilepsy.

Visual Function 20 Years After Childhood Hemispherectomy for Intractable Epilepsy.

Purpose: To investigate visual function in adults post hemispherectomy in childhood.

Design: Noncomparative case series.

Methods: All participants underwent visual acuity, binocular function, visual field, optical coherence tomography (OCT) of the retinal nerve fiber layer (RNFL), and monocular pattern reversal visually evoked potentials (prVEP).

Multichannel visual evoked potentials in the assessment of visual pathways in children with marked brain abnormalities.

Purpose: To demonstrate how multichannel visual evoked potentials (VEPs) can provide quantitative measures of visual function in children with marked cortical anatomy abnormalities.

Methods: Four children with marked brain pathology (2 holoprosencephaly, 2 giant interhemispheric cysts with hydrocephalus) underwent pattern reversal and flash VEP recordings from 16 equally distributed electrodes. Voltage maps of the major VEP components were constructed, and their distributions were compared to the magnetic resonance imaging (MRI) findings.

A case of internal ophthalmoplegia associated with varicella zoster.

The authors report a case of internal ophthalmoplegia in a 5-year-old boy presenting after primary varicella infection. This is an uncommon and mostly irreversible ocular manifestation after chickenpox. The internal ophthalmoplegia showed a potential mild improvement with oral acyclovir.