The influence of monocular peripheral sector prisms on driving in people with homonymous hemianopia Bart J.M. Melis-Dankers, PhD VISIO, Dutch National Foundation for visually impaired and blind people BiOptic Driving Conference, London, UK 18 – 20 June, 2004

University of Groningen, Groningen, the Netherlands Rens B. Busscher, MSc prof. Wiebo. H. Brouwer, PhD prof. Aart. C. Kooijman, PhD Schepens Eye Research Institute, Boston, USA prof. Eli Peli, PhD Alex Bowers, PhD Belgian Road Safety Institute (BIVV), Brussels, Belgium Mark L.M. Tant, PhD Dutch Central Driving Test Organisation (CBR) Ruud A. Bredewoud, MD Sander Bison Visio, Haren, The Netherlands Gert Dobbe

Mark L.M. Tant, PhD Visual Performance in Homonymous Hemianopia: Assesment, training and driving Tanja R. M. Coeckelbergh, PhD Effect of compensatory viewing strategies on practical fitness to drive in subjects with visual field defects caused by ocular pathology history

(left) hemianopia

left hemianopia, gaze right Eli Peli normal view

left hemianopia, gaze left Eli Peli normal view

left hemianopia, gaze far left Eli Peli normal view

Corrected binocular visual acuity: VODS ≥ 0,5 (VA ≥ 10/20) VODS ≥ 0,6, for monocular viewers(VA ≥ 12/20) No exceptions Visual field: Horizontal visual field ≥ 140 degrees Exception possible after special driving exam by Dutch Central Driving Test Organisation (CBR) legal requirements for driving in the Netherlands

left hemianopia MPSP monocular peripheral sector prisms Eli Peli

expected gain of visual field using MPSP left hemianopia left eyeright eye

simulated gain of visual field using MPSP left hemianopia left eyeright eye

number of subjects: 22 recruited 17 included gender: male: 15 female: 2 age: 56 years (range: 28 – 74) hemianopia: RHH: 7 LHH: 10 years since injury:5,5 years (range 2 – 13) VODS:0,8 ≤ VODS ≤ 1,6 (16/20 ≤ VA ≤ 32/20) all macular sparing subjects

left or right hemianopia with or without macular sparing age ≥ 18 years licensed or former driver generally good health no physical / mental disabilities no hemi-neglect inclusion criteria

test for inclusion visual and neuropsychological testing standardised test ride without MPS-prism fitting of upper MPS-prism adaptation period: two weeks fitting of lower MPS-prism adaptation period: two weeks Goldmann perimetry (binocular, with MPS-prism) 2 standardised test rides (random order): - 1 with MPS-prism - 1 with mock prism protocol

3 standardised test rides (random) - no MPS-prism - mock prism - with MPS-prism video records CBR: TRIP-scores / practical fitness-to-drive investigator in back seat test ride

OS no MPSP LHH ODS with MPSP LHH OD no MPSP LHH binocular field expansion on Goldmann perimetry: 17 / 17 objective results

practical fitness to drive: no MPSPmock MPSP with MPSP failed: doubt: 33 4 passed: 44 2 improved with MPSP:2 deteriorated with MPSP:5 no change with MPSP: 10 passed without MPSP – failed/doubt with MPSP:3 failed without MPSP – passed with MPSP:1 objective results

effectivity of MPS-prism for driving: - negative: 10 - neutral:4 - positive:3 comfort of MPS-prism for driving: - negative:9 - neutral:5 - positive:3 still using MPS-prism for driving: - no: 13 - yes, appreciation moderate:2 - yes, appreciation good:2 subjective results

Without proper training and supervised driving practice patients experience distraction by MPSP which leads to disappointing results. Belgium protocol: 16 subjects and 4 controls instruction directed at awareness of peripheral diplopia stress significance of diary subjects have to gain experience as passenger two test rides with supervised driving practice bifocal window for spot reading conclusion and suggestions

bifocal window for spot reading Eli Peli

Thank you for your attention Visio, Dutch National Foundation for the blind University of Groningen The Schepens Eye Research Institute Dutch Central Driving Test Organisation CBR Belgian Road Safety Institute BIVV