The aim of this study is to collect data on the early visual development of extreme premature infants. The method is the measurement of flash visual evoked potentials and the study population includes premature infants under the 28th weeks of gestation, who have normal cranial ultrasound examinations, normal aEEG, no clinical neurological symptoms and who have a normal ophthalmological status.

fVEP measurements were recorded from the first week of life every second week until term.

The fVEP recordings were performed in active sleep, in stable premature infants, who were continuously monitored. The Nihon Kohden Neuropack 8 was used, the stimulus frequency was 0,5 Hz, artefact free averages were analyzed.

The measurements were analyzed according to the presence and absence of known waveforms, their latencies and amplitudes. Longitudinal analysis was performed to analyse the effect of extrauterine visual development on fVEP with growing gestational ages.

Inclusion Criteria:

• All premature infants under the 29th week of gestation entering our ward.

Exclusion Criteria:

• Infants with intracranial abnormalities, cerebral malformations, neurological symptoms or known eye pathology.

Premature infants between the 23-29th week of gestation are included.