Detection and characterisation of visual field defects using Saccadic Vector Optokinetic Perimetry in children with brain tumours

Abstract

PurposeTo determine the ability of Saccadic Vector Optokinetic Perimetry (SVOP) to detect and characterise visual field defects in children with brain tumours using eye-tracking technology, as current techniques for assessment of visual fields in young children can be subjective and lack useful detail.MethodsCase-series study of children receiving treatment and follow-up for brain tumours at the Royal Hospital for Sick Children in Edinburgh from April 2008 to August 2013. Patients underwent SVOP testing and the results were compared with clinically expected visual field patterns determined by a consensus panel after review of clinical findings, neuro-imaging, and where possible other forms of visual field assessment.ResultsSixteen patients participated in this study (mean age of 7.2 years; range 2.9-15 years; 7 male, 9 female). Twelve children (75%) successfully performed SVOP testing. SVOP had a sensitivity of 100% and a specificity of 50% (positive predictive value of 80% and negative predictive value of 100%). In the true positive and true negative SVOP results, the characteristics of the SVOP plots showed agreement with the expected visual field. Six patients were able to perform both SVOP and Goldmann perimetry, these demonstrated similar visual fields in every case.ConclusionSVOP is a highly sensitive test that may prove to be extremely useful for assessing the visual field in young children with brain tumours, as it is able to characterise the central 30 degrees of visual field in greater detail than previously possible with older techniques.

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

“…This means there are children that need an assessment of their VF where formal perimetry is not achievable. Many researchers have recognised this problem and developed new perimeters that reduce the need for accurate subjective responses from the child by utilising eye movements [ 3 , 4 ]. The Saccadic Vector Optokinetic Perimeter (SVOP) is one such device and was successfully tested in 75% of a cohort of children with brain tumours (sensitivity of 100% and specificity of 50%), 12% in a cohort of children with neurodisability and 62.5% in a cohort of normal children with field loss [ 3 , 5 ].…”

“…Many researchers have recognised this problem and developed new perimeters that reduce the need for accurate subjective responses from the child by utilising eye movements [ 3 , 4 ]. The Saccadic Vector Optokinetic Perimeter (SVOP) is one such device and was successfully tested in 75% of a cohort of children with brain tumours (sensitivity of 100% and specificity of 50%), 12% in a cohort of children with neurodisability and 62.5% in a cohort of normal children with field loss [ 3 , 5 ]. In clinical practice when formal visual fields cannot be undertaken in a child, visual fields to confrontation are undertaken looking for the child’s behavioural responses.…”

Visual functions in children with craniopharyngioma at diagnosis: A systematic review

“…For future studies, it is important that all studies must use the correct testing methods for VA and VF and report these as such in the paper. Additionally, optical coherence tomography with analysis of the retinal layers might be applied as objective testing method in addition to VA and VF testing [ 84 , 128 – 130 ].…”

Lessons Learned from 23 Years of Experience in Testing Visual Fields of Neurologically Impaired Children

“…6 We believe that eye tracking applications might prove useful when testing VFs in children in the future. [32][33][34] Furthermore, predicting VFDs using OCT seems to be possible in children with a developmental age of 3-6 years. 35 In our centre the Octopus perimeter is not available and the HFA is sparsely used in children due to the extensive and positive experience of staff in testing children with or without NI using the Peritest.…”