Very encouraging on the sensitivity, and bodes well for the...

Very encouraging on the sensitivity, and bodes well for the technology as refinement proceeds. Not a formal study though, so carries limited weight more widely. It would be useful to know how many of the 10 cases wrongly labelled as ischaemic were actually bleeds, rather than normal.

In answer to Stezza's question, 'out of curiosity, what happens if clot busting drugs are used in these scenarios (excluding haemorrhage)', if clotbusters are used in a healthy person probably nothing, though there would be a small risk of causing a bleed in the brain or elsewhere. Conditions such as brain tumours might be induced to bleed.

Better specificity is needed for adoption as a true CT substitute. In other words, there is still a need to move closer to CT's ability to exclude haemorrhage, mainly because administering thrombolytics in the presence of a bleed could be catastrophic. The way I'm interpreting this, thrombolysis would still need CT (or another high-specificity bleed screen) until EMV’s haemorrhage algorithm meets perhaps ≥95 % specificity, at least with regard to not mistaking a bleed for ischaemia. I suspect this will be achieved before too long, given the rapidity of progress to date and the additional data being collected. It's important to make the point that EMV's device leans toward caution: it is almost twice as likely to over-call a bleed as to miss one, and the effect of this would be to delay thrombolytics pending a CT in a small number of patients.

Adopting an optimistic view for the medium/longer term, there are promising signs that once the specificity has been refined, EMV might actually be superior to CT, for instance the fact that EMV is far more sensitive in early ischaemic stroke and in the detection of sub-1 ml bleeds.

Even at the current specificity level, there are multiple areas where EMV would already have clear utility as an adjunct, essentially where conventional imaging is absent, slow, or impractical, among other things taking into account the much lower cost and minimal training and siting requirements with EMV. This isn't an exhaustive list, but for what it's worth: (i) ambulance triage of stroke before hospital, so that stroke management pathways can be initiated and time saved when the patient arrives, (ii) rural EDs/clinics without CT (iii) ICU on-site repeat checks without moving unstable patients (iv) CT backup during downtime (v) an affordable, radiation-free option for low- and middle-income regions (which is where most stroke deaths occur), (vi) detecting an ischaemic stroke at an early stage when CT is negative or equivocal but clinically there's something acutely wrong - although guidelines suggest treating without imaging evidence of ischaemia once a bleed has been ruled out, in practice there is often hesitation.