Refractive anomalies and visual activation in functional magnetic resonance imaging (fMRI): a versatile and low-cost MR-compatible device to correct a potential confound.

Purpose: To develop a magnetic resonance (MR)-compatible, versatile, easy-to-use, and low-cost device for refractive correction.

Materials And Methods: We retrospectively evaluated the application and practicability of the refractive correction in 110 subjects who had participated in various functional MR imaging (fMRI) studies with complex visual stimulation paradigms since the introduction of the MR-compatible lens frame at our site. The subjects consisted of 31 patients with Parkinson's disease (age range, 40-85; mean age, 63.