The videonystagmography performed by a camera and infra red light measures and records the eye movement, which is analyzed by the software. NYSSTAR II is the essential tool to study the various functions of balance, namely the oculomotricity (ocular saccades, pursuit, optokinetic nystagmus) and the study of the vestibular system (spontaneous and positional nystagmi, rotary tests, caloric tests. NYSSTAR II is a nystagmography system and is able to record simultaneously both eyes movements, as well horizontal, as vertical. The calibration carried out by camera is stable and should only be made once at the beginning of the examination. The recording by camera removes all artefacts due to the changes of polarity between the electrodes and the skin like with the interferences of electric and electrophysiological origin.
A graphic recorder used for detecting the electrical potential caused by eye movements. This recorder includes an electrode for each eye and one on the forehead (multichannel recording) for measuring the potential from both eyes simultaneously, or repositioning of the electrodes before each test for single channel recording. Electronystagmographs are used for detecting multiple sclerosis, vestibular dysfunctions, the presence of drugs and other specific disorders characterized by involuntary eye movement (nystagmus).