Medical aspects of fitness to drive a guide for medical practitioners

2.5 Myoclonus
Myoclonus associated with degenerative brain disease, post‐anoxic or metabolic
encephalopathies, sleep myoclonus and spinal myoclonus are not regarded as epilepsy,
and therefore are not treated the same way.
Medical standards for all licence classes and/or endorsement types
When driving should cease
Individuals with myoclonus that has features suggestive of epilepsy, or where the
myoclonus jerk(s) may impair driving, should be treated the same way as for tonic
clonic epilepsy.
When driving may resume or may occur
Individuals with myoclonus may be allowed to drive provided that no other features are
suggestive of epilepsy, and the jerky movements are not likely to make driving unsafe.
Some individuals may require an occupational therapist’s driving assessment.
2.6 Cerebrovascular disease
This group of conditions includes strokes arising from occlusive vascular disease
(cerebral thrombosis), spontaneous intracerebral haemorrhage and transient
ischaemic attacks. People who have suffered strokes are at increased risk of a second
attack that may render them unconscious or incapable of handling a motor vehicle.
The residual effects of stroke in terms of hemiplegia or other neurological sequelae
such as perceptual and visual problems, as well as effects on cognition, are often
sufficient to render an individual unfit to drive. Transient ischaemic attacks may also
render an individual unconscious or unable to control a vehicle.
2.6.1
Cerebrovascular accident (CVA)
Where there is doubt about fitness to drive in terms of residual disability in any area,
a driving assessment by an occupational therapist trained to provide off‐road and/or
on‐road assessments should be undertaken.
Medical standards for individuals applying for or renewing a class 1 or class 6 licence and/or
a D, F, R, T or W endorsement (see appendix 3)
When driving should cease
An individual should not drive until clinical recovery is complete, with no significant
residual disability likely to compromise safety. However, this period should not be less
than one month from the event.
Individuals with the presence of homonymous hemianopia are generally considered
permanently unfit to drive. The presence of other disorders such as ataxia, vertigo and
diplopia will also generally make individuals permanently unfit to drive unless there is a
full level of functional recovery.
The presence of epilepsy‐associated significant cardiovascular disorders and recurrent
transient ischaemic attacks following a stroke will generally result in individuals being
considered unfit to drive.
When driving may resume or may occur
Driving may resume when there has been satisfactory clinical recovery, providing
that there is no residual limb disability that cannot be accommodated by appropriate
vehicle modifications, and there is no evidence of cerebral damage resulting in
cognitive defects, reduced reaction times, perceptual difficulties and visual problems
such as homonymous field defects and/or hemispatial neglect.
Individuals are generally considered unfit to drive where there is the presence of
epilepsy, associated significant cardiovascular disorders and recurrent transient
ischaemic attacks following a stroke. In exceptional circumstances, the Agency may
consider granting a licence after 12 months if a supporting specialist physician or
26 2. Neurological and related disorders | Medical aspects of fitness to drive | NZTA July 2009
July 2009 NZTA | Medical aspects of fitness to drive | 2. Neurological and related disorders 27