Visual Function Score: A New Clinical Tool to Assess Visual Function and Detect Visual Disorders in Children

Abstract

IntroductionA comprehensive assessment of visual functioning at an early age is important not only for identifying and defining visual impairment but also for planning personalized rehabilitation programs based on the visual diagnosis. Since existing tools to evaluate visual functioning present some important limitations (e.g., they are based on qualitative reports, they do not take into account environmental adaptations of visual testing or they have not been formally validated as clinical instruments), the present work has the main aim to propose a new clinical tool (Visual Function Score, VFS) to detect and define visual disorders at an early age.MethodsThe Visual Function Score was administered to one hundred visually impaired children (age range 4 months to 17.75 years old) in the form of a professional-reported protocol for a total of 51 items, each of which is assigned a score from 1 to 9 (or from 0 to 9 in some specific cases). The VFS produces three sub-scores and a global score (from 0 to 100), resulting in a quantitative evaluation of visual functioning.ResultsThe VFS can detect the well-known differences between different types of visual impairment (cerebral, oculomotor, and peripheral or grouped as central and peripheral) and takes into account different environments in the definition of a quantitative score of visual functioning.DiscussionOverall, the use of a quantitative tool to evaluate visual functions and functional vision such as the VFS would be fundamental to monitor the progresses of patients over time in response to rehabilitation interventions.

Visual function in children with Joubert syndrome

“…Oculomotor function and nystagmus were evaluated for this work using clinical tools. 12 Quantitative studies with eye movement recording systems would provide more reliable and reproducible data both for clinical and for research purposes. Unfortunately, these technologies are rarely available in the clinical setting and require a level of cooperation that may be difficult to obtain for children with neuromotor and cognitive disorders.…”

“…On the contrary, when associated roving movements and poor pupil responses are present, a screening for retinal dystrophy would be highly recommended. Oculomotor function and nystagmus were evaluated for this work using clinical tools 12 . Quantitative studies with eye movement recording systems would provide more reliable and reproducible data both for clinical and for research purposes.…”

“…Functional disorders may involve any of the three components of visual function (i.e. the abilities to see, to look, and to understand), which plays a pivotal role in a child's development and global functioning 12 . Furthermore, along with multisystemic and ophthalmological involvement, a key finding in Joubert syndrome is developmental delay/intellectual disability, with neuropsychological profiles mainly characterized by deficits in processing speed and a relative sparing of verbal comprehension 13 .…”

“…A multidisciplinary team of trained professionals with experience in the diagnosis and rehabilitation of visual disorders (child neuropsychiatrists, therapists, psychologists, ophthalmologists, and orthoptists) performed and reviewed the evaluations, which were recorded. Basic visual functions were assessed and graded according to the Visual Function Score, a standardized tool derived from our centre's experience as well as from clinical practice guidelines (see, for example, Osborne et al 16 and Vinuela-Navarro 17 ), and previously presented by Signorini et al 12 See Figure S1 for a graphic representation of the multidisciplinary assessment. Best-corrected visual acuity was measured, when possible, according to the age and cooperation of the children, with a Snellen optotype or LEA Vision Test, 18 both in monocular and binocular vision and both for near (40 cm) and for far (3 m) distance.…”

“…the abilities to see, to look, and to understand), which plays a pivotal role in a child's development and global functioning. 12 Furthermore, along with multisystemic and ophthalmological involvement, a key finding in Joubert syndrome is developmental delay/intellectual disability, with neuropsychological profiles mainly characterized by deficits in processing speed and a relative sparing of verbal comprehension. 13 Psychiatric and behavioural disorders are significantly more common in Joubert syndrome than in the general population as well.…”