RESUMEN
Objective: To investigate if the use of vision therapy (VT) in convergence insufficiency (CI) has a significant neural impact and how it correlates with the clinical changes occurring with this option of treatment. Methods: A systematic review of the scientific literature was carried out in the PubMed and Scopus databases, where all the scientific literature on the neural impact of VT in CI was analyzed. A total of 17 articles were initially found and a detailed analysis was carried out. After full-text reading, only four studies met the defined inclusion criteria. The following data from them were extracted: CI cases and controls, clinical and neural parameters evaluated, the neural response to VT observed, type of study, and VT performed. The quality of the studies was assessed using the GRADE tool. Results: Some neural changes have been reported after VT in CI with the use of functional magnetic resonance imaging (fMRI). Specifically, a modification of the functional activity of some brain areas (especially front fields, oculomotor vermis, and cerebellum) was found. However, contradictory findings in terms of the change in functional activity (increase or decrease) were found that might be associated to differences in fMRI protocols. In the GRADE analysis, serious concerns were found in the categories of risk of bias, inconsistency, indirectness, and imprecision, so the certainty of evidence for each outcome was very low. Conclusion: The research performed to this date does not allow confirming if there are neural changes occurring after vision therapy in patients with CI because the quality of the research performed on this issue is very low, with several methodological concerns.
RESUMEN
CLINICAL RELEVANCE: Perception of optometrists and ophthalmologists of vision therapy (VT) as well as their methods for performing the sessions is of great importance for understanding the problems that professionals face and what should be improved in their clinical practice. BACKGROUND: The objective of this study was to determine the perception of VT and protocols used by eye care professionals globally. METHODS: A cross-sectional study was performed among eye care professionals internationally. The participants completed via online (Google Forms) a questionnaire of 40 questions on their perception and clinical practice of VT. The survey only permitted one answer per email address and was only collected if professionals gave their consent to participate. RESULTS: A total of 205 professionals from 43 countries answered the questionnaire (171 optometrists and 34 ophthalmologists). Accommodation and convergence problems were the main indication reported for VT (47.8%), followed by amblyopia (26.3%). The principal negative factor associated to VT was the limited number of professionals dedicated to this field (55.6%). The most common program of VT was the combination of VT sessions at home and at office (85.5%), with a great variability in terms of duration. Few professionals made use of the new technologies when programming VT, such as eye trackers (2.7%) or virtual reality (6.4%). European professionals surveyed had a more negative perception of VT (p < 0.031). CONCLUSIONS: Eye care professionals globally perceive VT as a scientifically based procedure. Overall, they believe that it has low recognition and prestige, especially ophthalmologists. A great variability in the programming of VT sessions was found, which highlights the need for standardised protocols that professionals could follow in their clinical practice.