Trial of Pattern Reversal Visual Evoked Response in Patients with Visual Conversion Reaction

Purpose: To investigate the usefulness of pattern reversal visually evoked response (PVER) for visual assessments on patients with visual conversion reaction (VCR). Subjects and Methods: We performed PVER on 30 patients suspected as the VCR, who visited our hospital between October 2005 and September 2006. The 25 cases out of 30 were girls. Their ages ranged from 5 to 15 years old with a mean of 9.5 years old. In addition to the visual acuity test, the pattern reversal VER, both steady-state and transient stimulation,were recorded in all patients. Results: Visual acuity improved to normal level with the neutralization method in 75% of eyes. The transient VER showed normal reaction in 96.7% of eyes, and the prolongation of implicit time was observed only in 3.3% of eyes. The steady-state VER were recordable in all check sizes. The bandpass shape VER amplitude-check size function curve was observed in 80% and in the rest of 20%, the curve was somewhat irregular. Conclusion: In the present study, the PVER was quite normal even though the visual acuity and visual field showed grossly abnormal. Hence we concluded that the PVER may be helpful to establish the diagnosis of VCR.