System 2000 Auto-Traverse Rotational Chair
System 2000 Auto-Traverse Rotational Vestibular Chair Brochure
Auto-Traverse Rotational Chair
System 2000™ Auto-Traverse is an enhanced rotational vestibular chair for testing patients with dizziness, war veterans with traumatic brain injury (TBI) or athletes with chronic traumatic encephalopathy (CTE). Advanced features include the ability to shift the center of rotation off-axis and to perform a dynamic subjective visual vertical test. Standard chair features include a dark room enclosure for eyes uncovered recording, an XY laser projector for ocularmotor testing in both horizontal and vertical directions, and a full-field optokinetic drum that projects moving stripes on the booth wall.
The System 2000 Auto-Traverse chair is used for testing and monitoring patients with peripheral vestibular loss, dizziness, CTE, TBI, blast injury, otolith dysfunction, vertigo, acoustic neuroma, chronic imbalance, eye tracking abnormalities and other vestibular disorders or brain injuries. A stepper motor shifts the chair left or right to place one ear off-axis during constant velocity rotation for otolith function testing using the subjective visual vertical laser.
Children who are candidates for cochlear implants or those who have balance or motor developmental issues can be tested in this chair by adding the pediatric option. This includes a child seat, pediatric monocular goggles and chair mounted nystagmus observation camera. Patients who are not candidates for caloric tests or those who need to be followed to document vestibular compensation are appropriate for the System 2000 rotational chair.
System 2000 Comprehensive Chair Features
Motor and Servo controller
The System 2000 Rotational Vestibular Chair smoothly accelerates and changes direction without inertial artifact even at higher frequencies and with heavier patients. The dc torque motor in the base and the linear servo amplifier were engineered to provide quiet, precisely controlled rotation in patients up to 400lbs. The complete system can be installed in a traditional 10ft x12ft exam room without expensive AC power modifications or room renovations.
Off-axis otolith testing
Otolith organs are important for a patient’s balance, walking and perception of vertical. Testing otolith function in a rotational chair requires centripetal acceleration and a way to measure the ocular tilt reaction. With the micro-centrifuge capability of this rotational chair, the chairs ability to rotate the patient at a constant high velocity, and the XY laser line projector together with software can be used to separately test left and right ear otolith organs. A stepper motor precisely positions the patient off-axis at up to 7cm to the right or left of the center during high speed rotation. A laser line is then drawn on the wall for adjustment by the patient to their perceived vertical using a hand held RF controller with left/right SVV line rotation buttons. Vertical perception is a measure of ocular tilt reaction.
XY Laser Projector
A focused solid state laser with precise, dual galvanometers produces a red dot on the booth wall for gaze, pursuit, and saccade tests in both the vertical and horizontal directions. For patients who have difficulty sitting up straight due to back or neck issues, there is a forward adjustable head support with an integral distance ruler to correctly set the laser calibration angle.
To prevent patient orientation and for testing in complete darkness, a rotational chair booth is part of the system. Communication with the patient takes place with a 2-way intercom and infrared video monitoring. The booth has ventilation fans for patient comfort and LED lighting that can be used when the patient is not rotating.
A true optokinetic stimulus must fill the patient’s visual field. Only a full-field projector can create a perception of self-motion in subjects who stare at the stimuli as it rotates around them. A pinpoint of intense light in the center of the optokinetic drum projects clear stripes on the booth wall from floor to ceiling. These stripes are rotated by a servo motor for OKN tests and the stripes are stationary for vision enhanced VOR tests.
Binocular Video Goggles
Prior to testing, binocular goggles are placed on the patient’s face, both eye images are adjusted for clarity of image, a Velcro strap connects the goggles to the head support for head stability. Then via software, the eye images are centered on the computer screen. During testing, even when the patient slouches in their chair or sits straighter, the eye images can be centered and the tracking adjusted from the computer keyboard without re-entering the booth. These goggles features improve trace quality and reduce testing time.
System 2000 Auto-Traverse Chair Options
- Pediatric option includes a monocular child’s size video goggles, chair mounted nystagmus observation camera, and child car seat.
- EOG electrode amplifier on the chair is an alternative for patients who cannot wear the video goggles, have eye blinking artifacts, or children.
- VNG is available for adding caloric, gaze, positional, Hallpike and other nystagmus tests using the same computer and goggles but with a VNG exam table in the same room.
- Vorteq for testing higher frequency VOR function