The videonystagmography performed by a camera and infra red light measures and records the eye movement, which is analyzed by the software. HEADSTAR is the essential tool to study the various functions of balance, namely the oculomotricity (ocular saccades, pursuit, optokinetic nystagmus), the study of the vestibular system (spontaneous and positional nystagmi, rotary tests, caloric tests and the Video Head Impulse Test. HEADSTAR is a nystagmography system and is able to record movements of one eye: horizontal, vertical and rotary on option. 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. HEADSTAR is also equipped with gyroscope to record movements of the patient's head. Combination of movements of the eye and of the head allow to run VHIT tests and other oculomotor tests.
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).