Full-field stimulus threshold testing: a scoping review of current practice

Abstract

The full-field stimulus threshold (FST) is a psychophysical measure of whole-field retinal light sensitivity. It can assess residual visual function in patients with severe retinal disease and is increasingly being adopted as an endpoint in clinical trials. FST applications in routine ophthalmology clinics are also growing, but as yet there is no formalised standard guidance for measuring FST. This scoping review explored current variability in FST conduct and reporting, with an aim to inform further evidence synthesis and consensus guidance. A comprehensive electronic search and review of the literature was carried out according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis Extension for Scoping Reviews (PRISMA-ScR) checklist. Key source, participant, methodology and outcomes data from 85 included sources were qualitatively and quantitatively compared and summarised. Data from 85 sources highlight how the variability and insufficient reporting of FST methodology, including parameters such as units of flash luminance, colour, duration, test strategy and dark adaptation, can hinder comparison and interpretation of clinical significance across centres. The review also highlights an unmet need for paediatric-specific considerations for test optimisation. Further evidence synthesis, empirical research or structured panel consultation may be required to establish coherent standardised guidance on FST methodology and context or condition dependent modifications. Consistent reporting of core elements, most crucially the flash luminance equivalence to 0 dB reference level is a first step. The development of criteria for quality assurance, calibration and age-appropriate reference data generation may further strengthen rigour of measurement.

Role of Electrophysiologal Studies for Detection of Simulation and Aggravation in Ophthalmology

“…This, at the stage the modern ophthalmology is, cannot be achieved with the rest of the available imaging and functional studies we know. In support of this are several articles published this year that fully support the claims of Fishman GA. and co-authors on the relevance and irreplaceability of the EF methods for this type of expertise [19][20][21][22][23][24].…”

ISCEV and IPS guideline for the full-field stimulus test (FST)

“…If external or published reference data (e.g. [ 62 ]) are to be used they must be verified as appropriate for the local methods and equipment, with an understanding of possible limitations and how reference limits were defined.…”