Five children with a history of preterm birth (mean gestational age of 27 weeks; birth weight 870-1,380 g) and perinatal post-hemorrhagic hydrocephalus were examined ophthalmologically at ages ranging from 4-11 years. An extended visual evoked potentials (VEPs) examination was simultaneously performed, using pattern-reversal, motion-onset, and cognitive visual stimuli. Although 3 of the 10 eyes displayed about normal visual acuity (> or =0.9), all of the examined eyes were abnormal for at least one variant of the tested VEPs. Pathological changes in VEPs (missing responses, shape abnormalities due to delayed VEPs maturation, prolonged peak latencies, and reduced amplitudes) were roughly proportional to both gestational age and reduction in visual acuity. A more severe pathology was found in the motion-onset VEPs (in all five subjects - nine eyes) when compared to the pattern-reversal VEPs (in four subjects - eight eyes). These observations suggest that the magnocellular system/dorsal stream of the visual pathway (which is particularly activated in response to motion stimuli) may be more frequently affected in preterm children than the parvocellular system/ventral stream (tested mostly by the standard pattern-reversal VEPs). This pilot study may encourage further testing of the combined pattern and motion-related VEPs examinations in preterm children as a way of detecting hidden cortical/cerebral visual impairment (CVI).

• MeSH
• Child MeSH
• Gestational Age MeSH
• Humans MeSH
• Central Nervous System Diseases physiopathology   MeSH
• Infant, Premature MeSH
• Infant, Low Birth Weight MeSH
• Infant, Newborn MeSH
• Pilot Projects MeSH
• Child, Preschool MeSH
• Refraction, Ocular physiology   MeSH
• Visual Acuity physiology   MeSH
• Visual Pathways physiopathology   MeSH
• Evoked Potentials, Visual physiology   MeSH
• Visual Cortex physiopathology   MeSH
• Check Tag
• Child MeSH
• Humans MeSH
• Infant, Newborn MeSH
• Child, Preschool MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

Motion-onset related visual evoked potentials (M-VEPs) were recorded as a result of the three basic (translating, radial and rotating) and one complex (spiral) motion stimulations in five subjects. Low contrast, retinotopically scaled patterns evoked potentials with major motion-onset specific negativity N160 with maximum in the parieto-temporal region. All multidirectional motion stimuli elicited the motion-onset response of significantly higher amplitude and shorter latency compared to the translating (unidirectional) motion. The rotation-onset evoked potentials had significantly shorter latencies than the rest of explored stimuli. The most stable responses with the largest N160 amplitude were recorded to the radial motion. After masking of the central 20 degrees of the visual field these motion-onset VEPs were acquired without statistically significant amplitude drop. The efficiency and usefulness of the radial stimulus is presented in two clinical cases.

• MeSH
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Magnetoencephalography MeSH
• Motion * MeSH
• Reference Values MeSH
• Sensitivity and Specificity MeSH
• Photic Stimulation methods   MeSH
• Visual Fields physiology   MeSH
• Evoked Potentials, Visual physiology   MeSH
• Visual Cortex physiology   MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Comparative Study MeSH

Motion-onset visual evoked potentials were studied in 140 subjects by means of motion-onset stimulation either on a television screen or through back projecting via a moving mirror. The motion-onset visual evoked potentials were characterized in 94% of the population by a dominant negative peak with latency in the range of 135-180 ms. Motion-onset visual evoked potentials with a dominant positive peak, as described in the literature, seemed to be a variant of pattern-off visual evoked potentials, caused by the pattern-disappearance effect at the onset of motion with a high temporal frequency (the multiple of the spatial frequency of the structure and the velocity of motion) of more than 6 Hz. Such visual evoked potentials occur mainly when the stimulus is limited to the macular area only. Additionally, other stimulus and recording conditions were found to be suitable for acquiring the specific motion-onset potentials without their contamination by pattern-related components. These conditions were as follows: an aperiodic moving pattern (e.g., random dots) with a low contrast (less than 0.2); a short duration of motion (less than or equal to 200 ms) and a sufficient interstimulus interval (at least five times longer than the motion duration) to decrease the adaptation to motion; and extramacular stimulation and recording of visual evoked potentials from unipolar lateral occipital leads. Such leads should be used because of the lateralization of these visual evoked potentials (mainly to the right occipital area), which is consistent with their assumed extrastriate origin.

• MeSH
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Pattern Recognition, Visual physiology   MeSH
• Motion Perception physiology   MeSH
• Evoked Potentials, Visual physiology   MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Female MeSH
• Publication type
• Journal Article MeSH

The results of motion-onset visual evoked potentials and pattern-reversal visual evoked potentials were compared in 5 adults with amblyopia, in 13 patients with unilateral retrobulbar neuritis and in 62 patients with multiple sclerosis. While the pattern-reversal visual evoked potentials had reduced amplitudes and prolonged latencies in all amblyopic eyes, the motion-onset visual evoked potentials were normal. Thus, motion-onset visual evoked potentials cannot be used for diagnosis of amblyopia. In patients with retrobulbar neuritis, both types of visual evoked potentials were delayed on stimulation of the affected eye. The latency increase was, however, greater for pattern-reversal visual evoked potentials than for motion-onset visual evoked potentials. Examination of the patients with multiple sclerosis showed that the additional use of motion-onset visual evoked potentials increased the sensitivity of the investigation. In some patients, only the motion-onset visual evoked potentials had pathologic latency increases, whereas the pattern-reversal visual evoked potentials stayed within normal limits.

• MeSH
• Amblyopia diagnosis   physiopathology   MeSH
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Pattern Recognition, Visual * MeSH
• Multiple Sclerosis physiopathology   MeSH
• Light MeSH
• Motion Perception * MeSH
• Optic Neuritis diagnosis   physiopathology   MeSH
• Evoked Potentials, Visual * MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Publication type
• Journal Article MeSH
• Comparative Study MeSH