Combi VNG/ HIT
Vestibular Diagnostic
Product description
Videonystagmography is a diagnostic method that is used for the differential diagnosis of balance disorders by recording eye movements. The sensorimotor system (sensory perception and movement) is responsible for an intact sense of balance; its central component is the vestibulo-ocular reflex (VOR). Disorders in this system can result in dizziness and impairments to the sense of balance. Computer technology lends itself positively to making complex nystagmography analyses easier. To this end, the VNG is connected to a PC or Notebook through a USB 2.0 interface. The highly specific algorithm is capable of identifying the pupil in an eye image and parameterising it. Even eyes with make-up can be measured. Eye movements are automatically imaged and analysed. The application programme is based on a patient database that contains all related data such as basic patient data, exam-specific data and test data, and makes them available to the user at the press of a button. It analyses the test data independently and presents it on a monitor together with the video image of the patient‘s eye. In its basic version, the programme offers tests for spontaneous nystagmus and calorifics, as well as positional nystagmus tests. Expanding it to include saccadic, optokinetic and swivel chair tests is possible at any time. The HIT – Head Impulse Test was designed for the daily work in the set up practice and the clinical application. It impres- ses by its great circumference of functions with intuitive handling. With HIT USB a complete system
is available for you to examine the semicircular canals. The test was rst described in 1988 by Curthoys and Halmagyi. As now been shown in many studies, the head impulse test should be a standard test in vestibular diagnosis. The system offers the functionality of a complete one-off solution to you. Also, the stress for the patient is signi cantly reduced. The tested canal is always in the direction of rotation. This means at a rotation of the head to the right, the right canal is excited and vice versa. For the vertical semicircular canals, this also applies. The test uses the vertical planes of the canals in the front and rear, which are located at an angle of approximately 45° to the sagittal plane. The results are shown in realtime. The normal reaction to the stimulus is almost the complete opposite of the head movement with a smooth eye movement. The gain is calculated for each trial. The gain ratio between head an eye movement should nearly be 1. If there is an issue with a semicircular canal the patient loses the target and there will be compensation saccades. If the gain is in the grey area, there can be a disease. If only one side is affected there will be two seperated point clouds. Additional to the gain and movement display, the HIT USB software offers a 3D-depiction of the eye response.
Technical specifications
Technical details VNG:
System:PC- Module
System requirements:PC or Laptop with Intel Core i5 Processor 2,2 GHz, 2 GB RAM, 1 GB grafic card, min. 2x USB 2.0, Monitor: 1600 x 900 Pixel, compatible with
Windows XP/ 7, 8 or 10 (32/64 Bit)
Sample rate:binocularly 100 Hz (100 images/s)
Resolution:0,1°
Camera:520 x 360 Pixel
Video recording:automatic nystagmus detection
Video mask:sharpness adjustment, stable binocularly video goggle with mask cover, mirror adjustable in 3 steps, soft cushion for optimal and comfortable fit
Tests:• spontaneous nystagmus
• position/ positioning test
• caloric irrigation
• optokinetics
Accessories:video mask with connection cables, foot pedal, installation-CD, manual
Technical Details HIT:
System requirements:PC or Laptop with Intel Core i5 Processor, 2,2 GHz and min. 2 free 2-0 USB-ports, 2 GB RAM, graphic card 1 GB,
Windows 7, 8 or 10, monitor with min. 1920 x 1080 Pixels
System:Infrared LED 700-1050 nm
Video:100 frames /sek, 8-Bit incl. slow motion function
Resolution:520 x 360 Pixel
Video-Format:AVI format
Camera type:100 Hz
Control:per foot pedal
Auswertung:• HOR, VOR, LARP, RALP
• 3D-Analysis
• Canalogram by Walther
Accessories:combi mask with 3D gyroscope and connection cable, foot switch with cable, HIT Software for Windows, Installations-CD, manual