Abstrakt
Purpose: Visual evoked potentials (VEPs) were used for objective testing of visual functions during treatment courses of Lyme neuroborreliosis (LNB) in adult patients in the Czech Republic. Methods: In 30 LNB patients with originally delayed VEP latencies, pattern-reversal (R-VEP) and motion-onset (M-VEP) VEPs were repeatedly examined within one to eight years.
Results: Six patients had Lyme optic neuritis (ON), five from them displayed prolonged latencies in both R-VEPs and M-VEPs, and one had only abnormal R-VEPs. VEP recovery to normal latency values was in three of them.
In the group of 24 LNB patients without ON, 14 patients displayed prolonged latencies only to motion stimuli and 10 patients had abnormal latencies both in R-VEPs and M-VEPs. During the follow-up period, 7 patients displayed shortening to normal latencies.
In 5 patients VEPs latencies improved only partially and in the remaining 12 patients VEPs did not improve at all. Conclusions: This study provides objective evidence that in LNB majority of patients without clinically manifesting ON display optic pathway involvement - predominantly magnocellular system/dorsal stream function changes.
In cases with ON, however, mainly the parvocellular system is affected. About half of cases without ON improved with a relatively long time course of latency shortening.