BVA

Binocular Vision Analyser

Advanced Hess Screen and Field of Binocular Single Vision test

What is it and who is it for?

The BV Analyser is designed to be used by Orthoptists, Ophthalmologists and Optometrists to assess ocular motility.

The software includes an advanced Hess Screen test and a test of Field of Binocular Single Vision.

The system was originally developed in collaboration with orthoptists at Moorfields Eye Hospital and is available as software only or as a complete solution including bespoke instrument table, 48'' monitor and touch screen PC.

The system is in use in numerous hospital eye departments and optometric practices.

Call now to arrange for an on-line demonstration.

BVAnalyser Composite

Binocular Vision Analyser software

£32 +VAT / month

  • Includes all upgrades, updates and support. Minimum term 6 months.

BVA Software Pricing

The Binocular Vision Analyser software is available for a subscription of £32+VAT / month.

The software requires a PC running Windows 7 (or later) and dual monitors.  The second monitor should be a large as possible (ideally a 49'' TV).  The software will run on a smaller monitor but the size of the field will be restricted to less than +/- 30 degrees.

BVA Bespoke Hardware

£4950 +VAT

  • Includes bespoke electric instrument table, 49'' TV, Touch-screen PC, Headrest, Installation and training: Excludes software

Hospitals: please contact us for further information, an on-line demo and a full quote.

Red/Green Diplopia Goggles

£45.00 £54.00 (incl.VAT)

Wrap around Red/Green goggles designed to be used with the BV Analyser or Hess Screen

BVA Bespoke Hardware

The BVA Bespoke Hardware consists of an electric instrument table, 49'' TV, Touch-screen and Headrest.  We will pre-install and calibrate the system and provide full on-site training.

We can also provide an ongoing support contract for the hardware.

BVA Home

A whirlwind tour of the Binocular Vision Analyser ...

A more detailed look at the Binocular Vision Analyser

The BV Analyser is based on software originally developed by Prof David Thomson and validated at Moorfields Eye Hospital. The software includes a Hess Screen test, a Field of Binocular Single Vision test and an Orthoptic Report generator.

The system is available as software only or as a complete solution as shown in the image opposite.

The complete solution includes:

  • Bespoke instrument table allowing wheelchair access
  • Head and chin rest
  • 48'' monitor
  • Touch-screen all-in-one PC
  • BV Analyser software
  • Installation and training

The patient places their chin and forehead on the rest and views the 48'' monitor from a distance of 40cm.

The Orthoptist controls and monitors the test using the all-in-one computer mounted on a swinging arm next to the test screen.

BVA Home
HessTest
HomePCHess

Hess test

With their head on the chin/forehead rest and wearing red/green goggles, the patient is instructed to view the monitor in front of them. The room lights are extinguished and a red and a blue circle are displayed on the screen (the right eye sees the red circle and the left the blue).

Initially the red circle is placed in the top left of the screen and the patient is instructed to move the blue circle using the mouse until it appears to be centred on the red circle.

As the eyes are dissociated, any deviation in this direction of gaze will result in a misalignment of the circles. This is repeated for either 9 or 25 directions of gaze (depending on the option selected). The colour of the circles is then reversed and measurements repeated with the left eye fixating.

Torsion may also be measured in each direction of gaze using a stimulus configuration devised specifically for the system,

Results are then displayed in the conventional format on the screen. A number of analytical tools can then be applied to the data to help the clinician establish a diagnosis.

Field of Binocular Single Vision

With their head on the chin/forehead rest the patient views a stimulus which is slowly scrolled from the centre of the field to the periphery along a series of radial lines at 15 degree intervals.

The patient simply reports if/when the stimulus goes doubled. This point is then automatically recorded and the next radial is explored.

The Orthoptist views a test control screen as shown opposite.

The size and colour of the stimulus may be changed as can the scrolling speed.  A manual override allows the Orthoptist complete control of the test allowing specific areas of the field to be explored and retested.

The results are automatically added to the database and plotted on the screen or printed.  A pdf of the chart can be created and attached to the patient's electronic medical record.

FBSV Results
FBSV Patient view
FBSV Orthoptist View
OR Input

Orthoptic report

The orthoptic report provides a quick and efficient way for othoptists to enter the outcome of their examination and create a standard report.

Symptoms, History, Visual acuity, results of the cover test and motility are added along with the outcome of other binocular vision tests and the diagnosis.  A standard report is then created automatically and can be printed or attached to the patients electronic medical record.

OR Report

Key Features

Hess Screen

  • Rapid and accurate assessment of the size and direction of phoria / tropia in 9 or 25 directions of gaze
  • Option to measure torsion in each direction of gaze
  • Results plotted in conventional Hess screen format allowing the clinician to establish whether a deviation is concomitant or incomitant and which muscle is affected
  • A variety of analytical tools to help the clinician form a diagnosis
  • Dual screen option allows Orthoptists to monitor and control test from one screen while patient views the test screen
  • Powerful database
  • Charts may be printed or attached to electronic patient records
  • Easy for patient to use
  • Quick and accurate

 

Field of Binocular Single Vision

  • Rapid and accurate assessment of the field of binocular single vision
  • Semi-automated or manual test protocols
  • Wide range of test target sizes and colours
  • Automated recording
  • Dual screen option allows Orthoptists to monitor and control test from one screen while patient views the test screen
  • Powerful database
  • Charts may be printed or attached to electronic patient records
  • Easy for patient to use
  • Quick and accurate

∗ Compulsory support contract required for this product.

Hospitals using BVA