Ischaemia is a condition in which the blood supply to any part of the body is so severely restricted that it receives no oxygen and can result in a stroke. Early detection is crucial, and so, medical devices company EMVision (ASX: EMV) has been conducting multi-site clinical trials to advance its neurodiagnostic AI algorithms to help catch suspected haemorrhagic or ischaemic strokes early on. 

Its stage 2 interim data analysis from the EMVision Brain Scanner confirms positive AI algorithm performance to help answer the clinical question of ischaemia or not (‘clot or not’). The AI algorithm was able to identify patterns and features across complex ischaemic patient data sets, including early-onset hyperacute ischaemic stroke. This is often challenging to detect on the traditional non-contrast computed tomography (NCCT), an imaging technology that clearly shows veins and arteries.

Principal investigator at Royal Melbourne Hospital, Dr Angela Dos Santos, commented, “The positive interim results for ischaemia detection, considered alongside those previously for haemorrhage detection, illustrate the technology’s evolving capability in addressing [two] of the most pressing questions at acute suspected stroke presentation: is there a stroke, and if so is it haemorrhagic or ischaemic? Timely answering of these questions allow the most effective care pathway to be activated as early as possible.”

In Stage 2 of the pre-validation trial, 180 patients were enrolled. Patients presented to the emergency department had stroke-like symptoms across the three trial sites: Liverpool Hospital, Royal Melbourne and Princess Alexandra Hospital Brisbane. 

75 patients had confirmed ischaemic strokes and 105 non-ischaemia cases (including 18 haemorrhagic strokes (caused by bleeding due to a ruptured blood vessel)), 67 stroke mimics and 20 transient ischaemic attacks (TIA).

The Alberta Stroke Program Early CT Score (ASPECTS) quantified early ischaemic changes detected on brain CT scans to measure the extent of brain damage in ischaemic stroke patients. 

The American Heart Association recommends that brain imaging and neurodiagnosis be performed as quickly as possible for patients suspected of having an acute ischaemic stroke. In most cases, this initially involves a NCCT scan. Rapid imaging is critical for patients who may benefit from treatments such as IV alteplase (clot-busting drugs) and/or mechanical thrombectomy (clot retrieval). 

NCCT brain scans exclude haemorrhage (‘blood or not’) in patients with clinical signs of stroke, which is essential when considering thrombolysis treatment (clot-busting). The literature on NCCT shows a limited sensitivity to detecting acute ischaemia. 

For patients with suspected ischemic stroke, advanced imaging modalities such as CT Angiogram, CT Perfusion or MRI are often used to confirm the presence of ischaemia (‘clot or not’) and determine a patient’s eligibility for thrombectomy (clot retrieval). Depending on the neuro-diagnosis and treatment capabilities of the hospital to perform an urgent intervention, a time-critical decision is whether to transfer the patient to a comprehensive stroke centre or not. 

The urgency of stroke care underscores the need for more streamlined, accurate and timely tools to aid its diagnosis—and to determine whether it is a result of ischaemia or haemorrhage.

The capabilities shown in EMVision’s interim cross-validation analysis across Stage 2 data demonstrate the potential of its technology to improve the diagnosis, care, and outcomes for both haemorrhagic and ischaemic stroke patients.

At the end of Q3 FY24, the Company had cash reserves of $21.3 million, including a $15.2 million investment from US tech company Keysight. It had net operating cash outflows of $2 million and net investing cash outflows of $0.35 million.

Patient recruitment for the final Stage 3 of the Pre-Validation clinical trial is on track to be completed in the coming months, with over half the target cohort (up to 30 haemorrhages) recruited already. 

2025 onwards, the Company expects to initiate market entry into the US and Australia.