CT Clock Tool Feasibility Study

NCT06028802 | Completed

• 3 other identifiers: AC23097MRC/IAA/003330583
• Study Type: observational
• Target: 35
• Locations: 1 country
• Sites: 1

Brief Summary

Interruption of blood supply to the brain from a blocked blood vessel causes ischaemic stroke. This leads to symptoms relating to the areas of brain affected. For example, people with stroke may suddenly have trouble moving their arms, legs or face, and may find it hard to speak or lose consciousness. There are treatments available to open up the blocked blood vessel:

• Thrombolysis involves injecting a medicine to break down the blood clot causing the blockage.
• Thrombectomy means pulling the blood clot out through a tiny tube placed within the blood vessel. Both treatments can help restore blood supply to the brain and reverse the symptoms caused by stroke. These treatments are usually only offered when there is a clear onset time for stroke symptoms. However, for around 20% of strokes, the time of onset is unknown. Patients may wake up with symptoms, be confused or be found collapsed. So that treatment can be available to more people, the investigators have developed a method to estimate when an ischaemic stroke began, the CT Clock Tool. This method involves taking measurements from the brain imaging that most patients with stroke routinely get on arrival at hospital (CT or CAT scanning). In other words, no extra tests are needed to use the method; the investigators seek to make better use of existing tests. In this study, the aim is to understand whether it is feasible to use the CT Clock Tool method in the real world. For example, can doctors correctly use the tool during their normal work to produce accurate estimates for the onset time of stroke? The results of this study will be used to plan a future clinical trial for testing the safety of the CT Clock Tool when it is used to treat patients.

Conditions

Ischemic Stroke, Acute

Outcome Measures

Primary Outcomes (1)

• Feasibility of front-line clinicians (stroke clinicians and radiologists) using the CT Clock Tool method during routine care

  Proportion of cases where a front-line clinician successfully uses the CT Clock Tool method in the acute setting, i.e. acquires CT measurements (regardless of result)

  CT Clock Tool measurements to be acquired on the day of patient admission (baseline)

Secondary Outcomes (5)

• Comparison of stroke onset time estimates provided by front-line clinicians using the CT Clock Tool with actual elapsed time

  Baseline

• Diagnostic accuracy of these time estimates for determining treatment eligibility relative to standard thrombolysis and thrombectomy limits (4.5 and 6 hours, respectively)

  Baseline

• Whether estimates of brain tissue viability correlate with equivalent CTP findings

  Baseline

• User experience of the CT Clock Tool on a (Likert) satisfaction scale

  Baseline

• Inter-rater agreement

  Baseline

Study Arms (2)

Visible lesion

Patients where an ischaemic lesion is visible on non-enhanced CT acquired at baseline.

Diagnostic Test: CT Clock Tool measurement

Non-visible lesion

Patients where an ischaemic lesion is not visible on non-enhanced CT acquired at baseline.

Diagnostic Test: CT Clock Tool measurement

Interventions

CT Clock Tool measurement DIAGNOSTIC_TEST

Ratio of CT attenuation measurements acquired from within the visible ischaemic lesion (or estimated location if not visible) ÷ CT attenuation measurements acquired from within the equivalent normal brain.

Non-visible lesion; Visible lesion

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Investigators will recruit adult patients presenting acutely to the emergency department with symptoms of stroke, where non-enhanced brain CT excludes haemorrhage and other structural causes for symptoms (i.e. ischaemic stroke is the most likely diagnosis).

You may qualify if:

• With and without a known time of stroke onset.
• With a stroke severity score (NIHSS) \>4
• With suspected anterior or posterior circulation ischaemic stroke.
• Over 18 years of age with no upper limit.
• Patients with and without concurrently acquired CTP imaging (acquired only for potential thrombectomy candidates, approximately 20%)
• Patients able to provide informed consent (including witnessed consent when loss of functional ability is evident, e.g. upper limb weakness in dominant hand or visual loss).

You may not qualify if:

• With a suspected lacunar syndrome (i.e. pure motor stroke, pure sensory stroke, mixed sensorimotor stroke \[without cortical signs\], ataxic hemiparesis, dysarthria-clumsy hand syndrome).
• Where CT brain imaging demonstrates a non-ischaemic cause for stroke symptoms, e.g. brain haemorrhage, tumour or other relevant structural abnormality.

Sponsors & Collaborators

• University of Edinburgh: lead
• NHS Lothian: collaborator

Study Sites (1)

Royal Infirmary of Edinburgh

Edinburgh, EH16 4SA, United Kingdom

Location

Related Publications (2)

• Mair G, Alzahrani A, Lindley RI, Sandercock PAG, Wardlaw JM. Feasibility and diagnostic accuracy of using brain attenuation changes on CT to estimate time of ischemic stroke onset. Neuroradiology. 2021 Jun;63(6):869-878. doi: 10.1007/s00234-020-02591-w. Epub 2020 Oct 30.

  PMID: 33128140 BACKGROUND

• Alzahrani A, Zhang X, Albukhari A, Wardlaw JM, Mair G. Assessing Brain Tissue Viability on Nonenhanced Computed Tomography After Ischemic Stroke. Stroke. 2023 Feb;54(2):558-566. doi: 10.1161/STROKEAHA.122.041241. Epub 2023 Jan 5.

  PMID: 36601950 BACKGROUND

Related Links

• Study website, will include results when available.

MeSH Terms

Conditions

Ischemic Stroke

Condition Hierarchy (Ancestors)

Stroke; Cerebrovascular Disorders; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Vascular Diseases; Cardiovascular Diseases

Study Officials

• Grant Mair, MD

  University of Edinburgh

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: CASE ONLY
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: August 25, 2023
• First Posted: September 8, 2023
• Study Start: October 26, 2023
• Primary Completion: October 25, 2024
• Study Completion: October 25, 2024
• Last Updated: November 8, 2024

Record last verified: 2024-11

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, CSR
• Time Frame: Available within 12 months of study end, available in perpetuity.
• Access Criteria: Open access.

Locations

GB (1)