Medical review licensing outcomes in drivers with visual field loss in Victoria, Australia

Visual field loss and falls requiring hospitalisation: results from the eFOVID study

BACKGROUND

Visual fields are important for postural stability and ability to manoeuvre around objects.

OBJECTIVE

Examine the association between visual field loss and falls requiring hospitalisation in adults aged 50 +.

METHODS

Older adults aged 50+ with and without visual field loss were identified using a fields database obtained from a cross-section of ophthalmologists' practices in Western Australia (WA). Data were linked to the Hospital Morbidity Data Collection and WA Hospital Mortality System to identify participants who experienced falls-related hospitalisations between 1990 and 2019. A generalised linear negative binomial regression model examined the association between falls requiring hospitalisation for those with and without field loss, based on the better eye mean deviation (mild: -2 to -6 dB, moderate: -6.01 dB to -12 dB, severe < -12.01 dB) in the most contemporaneous visual field test (3 years prior or if not available, 2 years after the fall), after adjusting for potential confounders.

RESULTS

A total of 31 021 unique individuals of whom 6054 (19.5%) experienced 11 818 falls requiring hospitalisation during a median observation time of 14.1 years. Only mean deviation index of <-12.01 dB (severe) was significantly associated with an increased rate of falls requiring hospitalisations by 14% (adjusted IRR 1.14, 95% CI 1.0-1.25) compared with no field loss, after adjusting for potential confounders. Other factors included age, with those aged 80+ having an increased rate (IRR 29.16, 95% CI 21.39-39.84), other comorbid conditions (IRR 1.49, 95% CI 1.38-1.60) and diabetes (IRR 1.25, 95% CI 1.14-1.37). Previous cataract surgery was associated with a decreased rate of falls that required hospitalisations by 13% (IRR 0.87, 95% CI 0.81-0.95) compared with those who did not have cataract surgery.

CONCLUSION

The findings highlight the importance of continuous clinical monitoring of visual field loss and injury prevention strategies for older adults with visual field loss.

Driving and exceptional cases: Supporting relicensing evaluation in patients whose visual fields fail to meet standards

PURPOSE

The UK Driver and Vehicle Licensing Agency's (DVLA) visual field criteria mean that homonymous defects close to fixation are not usually acceptable for driving. Here, we illustrate cases where patients with field defects failing to meet standards had their licences revoked but subsequently were permitted to drive again through exceptional case provisions.

METHODS

Clinical assessment of two patients with homonymous loss: a 62-year-old man (PWT) with a dense left upper homonymous quadrantanopia secondary to a right occipital lobe stroke and a 48-year-old woman (JC), only aware of right upper homonymous quadrantanopia following routine primary care assessment and subsequently attributed to left middle cerebral artery stroke from perinatal intracranial haemorrhage.

RESULTS

PWT's Esterman test showed a significant central defect failing to meet the standard. His subsequent ophthalmic examination was otherwise unremarkable with excellent visual functions. Clinical evidence was provided supporting his relicensing application, and in time, a practical DVLA driving assessment indicated adaptation had been successful, and his licence was restored. JC's defect also failed to meet the standard, and her licence was revoked. Her ophthalmic examination was otherwise unremarkable, and her condition was attributed to a nonprogressive, isolated perinatal event. The DVLA accepted supporting clinical evidence; her subsequent practical driving assessment demonstrated successful adaptation and her licence was also restored.

CONCLUSIONS

Conventional visual field tests are not necessarily predictive of real-world driving performance, with drivers' adaptive strategies not being accommodated. In the UK, individuals with visual field loss failing to meet the standard may be eligible for relicensing as exceptional cases if specific criteria can be met. For exceptional cases potentially licensable under these criteria, the DVLA requires clinician support and a satisfactory practical driving assessment. Similar provisions exist internationally. Clinicians need to be aware of the role they may play in such scenarios.