A study was made with intra-operative flash--visual evoked potentials (VEP) monitored using a fibre-optic/contact lens photo stimulator in 57 patients undergoing intra-orbital surgical procedures with potential risk to the optic nerve. The VEPs recorded under enflurane and nitrous oxide anaesthesia did not differ significantly in latency or amplitude from the pre-operative recordings. Transient...

A procedure for recording the electroretinogram (ERG) and the visual evoked potential (VEP) in freely moving cats was developed and used to test the visual toxicity of nalidixic acid. The electrodes for recording the ERG and VEP were implanted chronically in the sclera of the eye and on the surface of the visual cortex, respectively. Both the ERG and VEP were simultaneously recorded in freely m...

PURPOSE The aims of the study were to detect early changes in the optic nerve function of patients with Graves' orbitopathy (GrO) who do not have any signs and symptoms of optic neuropathy, using pattern visual evoked potentials (P-VEP), and investigate any possible relation between the disease activity and P-VEP P100 latencies of the patient group. METHODS The study was conducted in a tertia...

The pattern VEP is frequently abnormal in multiple sclerosis. In this disease the VEP latency is prolonged and the amplitude is reduced. The use of the VEP amplitude in diagnosis is limited because of the large interand intrasubject variability and low signal-to-noise ratio (SNR). Goal of this project is to improve the SNR of VEP’s with alternative averaging procedures, and to investigate wheth...

PURPOSE To present recovery from vision loss due to CO poisoning with Hyperbaric Oxygen (HBO) therapy in two patients. METHODS Two female patients developed visual deterioration after carbon monoxide (CO) poisoning and were treated with hyperbaric oxygen therapy (HBO). Clinical examination, including visual acuity assessment, visual field examination and visual evoked potentials (VEPs) before...

Objective: Steady-state visual evoked potentials (VEPs) were recorded to study the mechanisms that underlie visual attention. Methods: VEPs were recorded from 1 cycle/degree sinusoidal grating contrast reversed at various temporal frequencies (6–10 Hz). This was displayed in one hemifield. A letter search display was flashed at a random rate in the other hemifield. The subject performed a deman...

BACKGROUND Evoked potentials are used to detect conduction disturbances in the central nervous system. This paper provides an overview of the areas in which evoked potentials are used in clinical neurophysiological diagnostics, with the emphasis on coma and demyelinating disease. METHOD The article is based on a literature search in PubMed and the authors' long experience of neurological and ...

To search for a potential negative influence on the central nervous system (CNS) of the electromagnetic field emitted by a mobile phone, the authors performed a pilot experimental study of the influence of a single short acute exposure to the GSM mobile phone Motorola 8700, using visual evoked potentials (VEP) examination as an electrophysiological marker of CNS dysfunction. The study group con...

We have examined the role of benzodiazepine receptors in nitrous oxide-induced neuronal depression in rats. The changes in neuronal excitability induced by nitrous oxide and the benzodiazepine inverse agonist, Ro15-4513, were monitored by measurement of visual evoked potentials (VEP). Administration of Ro15-4513 10 mg kg-1 i.p., in rats breathing air, did not affect the amplitude or latency of ...