Background and purpose: Until now, stroke and transient ischemic attack (TIA) have
been clinically based terms which describe the presence and duration of characteristic
neurological deficits attributable to intrinsic disorders of particular arteries supplying the
brain, retina, or (sometimes) the spinal cord. Further, infarction has been pathologically
defined as death of neural tissue due to reduced blood supply. Recently, it has been
proposed we shift to definitions of stroke and TIA determined by neuroimaging results
alone and that neuroimaging findings be equated with infarction.
Methods: We examined the scientific validity and clinical implications of these proposals
using the existing published literature and our own experience in research and clinical
practice.
results: We found that the proposals to change to imaging-dominant definitions, as
published, are ambiguous and inconsistent. Therefore, they cannot provide the standardization
required in research or its application in clinical practice. Further, we found
that the proposals are scientifically incorrect because neuroimaging findings do not
always correlate with the clinical status or the presence of infarction. In addition, we
found that attempts to use the proposals are disrupting research, are otherwise clinically
unhelpful and do not solve the problems they were proposed to solve. Conclusion: We advise that the proposals must not be accepted. In particular, we
explain why the clinical focus of the definitions of stroke and TIA should be retained
with continued sub-classification of these syndromes depending neuroimaging results
(with or without other information) and that infarction should remain a pathological
term. We outline ways the established clinically based definitions of stroke and TIA,
and use of them, may be improved to encourage better patient outcomes in the
modern era.