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Missed some points on visual field test for DVLA

Question

Had field of vision test for DVLA. Out of 112 points, failed on eight. 5 points at roughly - 5 mins passed hour and 3 points at roughly 35 mins passed the hour. Would this justify my driving licence being withdrawn?

Answer Written answer:
Qualified optometrist Simon Kay BSc(Hons) MCOptom answers this question.

It depends. You are allowed to miss some points, but it depends on which part of the visual field shows a defect. The following is published by the Association of Optical Practitioners, and you will see that the assessment can be complicated:

There is no statutory requirement in UK legislation for fields of vision for Group 1 drivers but the Second EC Directive applies. The following standard is usually applied when there is evidence that a defect exists. The minimum field of vision for safe driving is defined as a field of vision of at least 120o on the horizontal measured by the Goldmann perimeter using the III4e settings (or equivalent perimetry). In addition there should be no significant defect in the binocular field which encroaches within 20o of fixation above or below the meridian. By these means homonymous or bitemporal defects which come close to fixation, whether hemaniopic or quadrantopic, are not accepted as safe for driving.

The DVLA requires a binocular Esterman field in the first instance to determine fitness to drive in those persons where a field defect is suspected. On occasion fields are required testing the full field with each eye individually. The advice to DVLA from the Secretary of State’s Honorary Medical Advisory Panel on Driving and Visual Disorders is that for Esterman binocular charts to be considered reliable for licensing, the false positive score must be no more than 20%. In addition, fixation losses where measured should be no greater than 20%. If fixation is not measured the tester must examine the candidate closely to ensure that fixation is good.

The following gives some guidance on DVLA’s interpretation of defects on the Esterman test

Defect affecting central area ONLY (Esterman) for GROUP 1 ENTITLEMENT

For GROUP 1 licensing purposes, pending the outcome of current research, the following are generally regarded as acceptable central loss:

  • Scattered single missed points

  • A single cluster of up to 3 contiguous points
    For GROUP 1 licensing purposes the following are generally regarded as unacceptable (i.e. 'significant')

    central loss:

  • A cluster of 4 or more contiguous points that is either wholly or partly within the central 20 degree area

  • Loss consisting of both a single cluster of 3 contiguous missed points up to and including 20 degrees from fixation, and any additional separate missed point(s) within the central 20 degree area

  • Central loss of any size that is an extension of a hemianopia or quadrantanopia. Exceptional cases for GROUP 1 ENTITLEMENT

    Group 1 drivers who hold, or who have previously held full driving entitlement, who have a field defect which does not satisfy the standard, can be considered as exceptional cases on an individual basis, subject to strict criteria. The defect must be both non-progressive and caused by a non-progressive condition and there must be no other progressive condition present which is likely to affect the visual fields. In order to meet the requirements of European law, DVLA will, in addition, require confirmation of full functional adaptation, together with a satisfactory practical driving assessment. Applicants for, or holders of, provisional entitlement, cannot be considered as exceptional cases.

    PERIPHERAL DEFECT

    The following will be disregarded when assessing the width of field:

  • A cluster of up to three missed points lying on or across the horizontal meridian

  • A vertical defect of only single point width but of any length, which touches or cuts through the horizontal meridian

 

Optician's Biography

Simon Kay BSc(Hons) MCOptom has been a qualified Optometrist for over 30 years, and has a vast experience of almost all aspects of optometry. He joined Specsavers Opticians in 1993 first in Liverpool and for 15 years as a director of Lancaster and Morecambe. He served on many panels and committees whilst a director, including those responsible for IT design and professional advancement. He was regional chairman of the North West directors of Specsavers for over 12 years and as such was involved in almost all aspects of optometry on a business and professional level. He has been involved on the Local Optical Committee for many years and is currently Vice Chairman in his area.
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