Electroretinogram (ERGs) and visual evoked potentials (VEPs) study in prion disease (CJD)

Literature reported on ERGs and VEPs changes in patients with prion disease (CJD). To characterize the extent of ERG and VEPs involvement in confirmed CJD; to assess ERGs and VEPs diagnostic usefulness in the workout of suspected CJD. White flash ERG ( a / b -wave, 30-Hz flicker, oscillatory potentials) and VEP (P1, N1 and P2 components) were recorded in 122 consecutive unselected CJD patients (57 females, 65 males, mean age: 61.98 years) and compared with: (a) normal and control non-CJD (sensitivity and specificity), and (b) EEG, MRI and laboratory tests. ERG changes were correlated with pathology of the retina performed in several cases. ERG/VEPs were abnormal in just over 60% of CJD, compared with 76% MRI and 66% EEG abnormal rate; ERG changes revealed definite correlation with the codon129, VEPs did not; giant VEPs was recorded in the MM subtype; the VV patients had the most severe retinal changes. Twenty-two patients recorded over a period of six months showed ERG deteriorative pattern, VEPs did not, for it remained stable. ERGs/VEPs revealed abnormalities in CJD patients whose EEG and/or MRI did not show typical changes; although nonspecific they contribute to propose a diagnostic workout of patients suspected of CJD.