Systemic thrombolytic therapy with rtPA is the standard treatment for acute ischemic stroke in patients within 4.5h from stroke onset [1,
2].
An extension of this time window is possible for endovascular treatment (EVT),
using intra-arterial thrombolysis or thrombectomy by different techniques [3, 4].
Furthermore,
for patients with unknown time of onset or wake-up stroke (WUS),
there is the possibility of offering thrombolytic treatment,
although the exact hour of onset is unclear,
by means of advanced neuroimaging techniques.
An MRI-based decision has nevertheless many limitations: emergency-MRI is not available in many hospitals,
some patient cannot undergo MRI due to contraindications or lack of information on previous clinical history,
or even lack of collaboration.
Thus,
MRI-based patient selection could be quite difficult in the real world.
As in most hospitals,
only CT-based techniques are feasible, the use of CT perfusion (CTP),
with or without CT angiography (CTA) is being incorporated commonly in most cases before treatment allocation.
Beside the advanced imaging techniques,
clinical decisions are based on patients' characteristics and history,
as well as on the findings on the baseline,
non-contrast computed tomography (NCCT), done upon arrival to the emergency room.
For its analysis,
an acceptable score has been developed,
the ASPECT score [5].
The actual role of CTA in acute stroke is mainly to provide information about vessels occlusion and status of collateral circulation,
thus,
driving the decision whether to candidate the patients to intraarterial thrombolysis or thrombectomy.
The role of CTP in the setting of i.v.thrombolysis and its utility is much less well-defined; in particular,
it is not yet clear which kind of patient could benefit from this technique [6,
7].
In an attempt to answer this question,
we planned a retrospective analysis of patients with acute ischemic stroke (AIS) admitted to our hospital,
who underwent all three investigations (NCCT,
CTP and CTA) and reanalyzed CTP's data with an expert-opinion retrospective blind analysis.
We focused in particular on CTP: the aim of the study was to evaluate if CTP data can be useful to help neurologists in assessing whether systemic i.v.
rtPA thrombolysis is indicated or not.