Περίληψη:
Background and Purpose: It was the aim of this study to systematically
review available literature on the accuracy of transcranial Doppler
(TCD) compared with angiography for the diagnosis of 6 50% middle
cerebral artery stenosis in patients with transient ischemic attack or
ischemic stroke. Methods: We performed a systematic review that included
original articles published on TCD accuracy from 1982 until the end of
December 2005 using angiography as the gold standard. The following
measures of diagnostic accuracy were obtained from each primary study:
sensitivity, specificity, positive predictive value (PPV) and negative
predictive value (NPV). Weighted mean averages were then calculated from
individual results for different velocity cutoffs. Results: Six papers
met our selection criteria. Using laboratory-specific variable mean flow
velocity cutoffs, self-reported best accuracy results yield a mean
weighted average sensitivity of 92%, specificity of 92%, PPV of 88%
and NPV of 98% for 80 cm/s cutoff. For 100 cm/s cutoff, the
sensitivities were 100%, specificity 97%, PPV 88% and NPV 100%.
Conclusions: Although limited to few reports, this analysis demonstrates
fair TCD performance against angiography. Since increasing velocity
cutoffs do not yield decreasing sensitivity and increasing specificity,
further studies are required to determine optimal velocity values and
possibly other criteria such as velocity ratios to develop a screening
test with balanced performance parameters. Copyright (c) 2007 S. Karger
AG, Basel.
Συγγραφείς:
Navarro, Jose C.
Lao, Annabelle Y.
Sharma, Vijay K. and
Tsivgoulis, Georgios
Alexandrov, Andrei V.
