The examination and evaluation of the visually impaired lawn bowler must be performed by a certified Ophthalmologist or Optometrist with experience in low vision assessment. The evaluation requires the measurement of each eye individually:
A. Best corrected visual acuity
B. Field of vision
- Visual Acuity Testing
The International Blind Bowls Association, in line with International Paralympic Committee (IPC) and International Blind Sport Association (IBSA), have adopted the Berkeley Rudimentary Vision Test (BRVT in logmar units) as the standard method used to evaluate visual acuity. A classification chart is attached to these forms and the findings are to be filled in the form accordingly for each eye separately and submitted together with all the required data.
B1 No light perception up to Logmar 2.7
B2 Logmar 2.6 up to Logmar 1.5
B3 Logmar 1.4 up to Logmar 1.0
B4 Logmar 0.9 up to Logmar 0.6 or with a field of vision less than 20 degree.
The best measure of visual acuity is obtained using the Single Tumbling E Chart to differentiate between B2 and B1 followed either with the Tumbling E letter chart (B2, B3 and B4) or the grating acuity card (B1). (See attached flow chart).
- Field of Vision
Standard methods should be employed to determine the field of vision. The method employed should be specified in the form and the findings/recordings should be submitted together with the form.
Visual field shall mean the total visual field (peripheral) and shall be taken as the maximum sum of the fields about the point of fixation along any line through the point of fixation (e.g. temporal plus nasal or upper plus lower), whichever produces the largest result.
The assessment shall be carried out by assessors independent from the player being assessed.
A classifier, appointed by the National Association, will check the forms and recommend a classification. This will be submitted to IBBA for confirmation prior to tournaments.
A copy of the relevant medical and visual history should be submitted together with the findings.
CLICK HERE to view Blank Sight Certificate Form.