Stepped-Wedge Cluster Randomized Trial of AI-Assisted CTA Detection for Intracranial Aneurysms in Regional Hospitals (IDEAL2)

Jinling Hospital, China

Status: Not yet enrolling

Conditions: Cluster Randomized Trial; CT Angiography; Intracranial Aneurysm; AI (Artificial Intelligence)

Treatments: Diagnostic Test: Standard CTA Interpretation; Device: AI-Assisted CTA Interpretation

Study type: Interventional

Funder types: Other

Identifiers

NCT07124624

2025DZKY-087-01

Details and patient eligibility

About

This study (IDEAL 2) is a nationwide stepped-wedge cluster-randomized trial designed to prospectively enroll over 14,400 patients undergoing outpatient head CT angiography (CTA). The trial will be conducted across more than 72 regional hospitals in China. Clusters were randomly assigned to nine randomization groups. In accordance with the stepped-wedge design, clusters will sequentially transition from the control condition (standard human diagnosis) to the intervention condition (AI-assisted diagnosis) at regular intervals over a 10-month period, until all clusters receive the intervention. The primary outcome is the detection rate of intracranial aneurysms. Secondary outcomes include patient prognosis and clinical outcomes.

Full description

A multicenter, stepped-wedge cluster-randomized trial will be conducted in regional hospitals, specifically prefecture-level and county-level institutions across China. Each cluster (i.e., hospital) will enroll approximately 200 patients undergoing head computed tomography angiography (CTA), yielding a total sample size of at least 14,400 participants. The trial consists of nine steps, each lasting one month. Clusters will transition sequentially from the control condition to the intervention condition based on stratified randomization, until all clusters have received the intervention.

In the control group, diagnoses and treatments will follow local standard clinical protocols. In the intervention group, diagnostic procedures will be supported by an artificial intelligence (AI)-assisted system. The primary outcome is the detection rate of intracranial aneurysms, as determined from radiology reports at the patient level. Secondary outcomes include additional diagnostic performance metrics on CTA, such as the detection of intracranial arterial stenosis, occlusion, and tumors.

Follow-up evaluations at 3 and 12 months will assess treatment-related indicators-including repeat head CTA or magnetic resonance angiography (MRA), hospitalization rates, and digital subtraction angiography (DSA) utilization-as well as clinical outcomes related to aneurysm events. These measures aim to evaluate both the short- and long-term impacts of AI-assisted diagnosis on routine clinical practice and patient prognosis.

Enrollment: 14,400 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

-Patients in the outpatient setting who are scheduled to undergo head CTA scanning

Exclusion criteria

• Age < 18 years
• History of cerebrovascular surgery involving any metallic implants (e.g., aneurysm embolization, aneurysm clipping, or vascular stenting)
• Modified Rankin Scale (mRS) score > 3
• Refuse to sign written informed consent
• Contraindications to CTA examination
• CTA scan failure, incomplete imaging data, or image quality insufficient for diagnostic evaluation

Trial design

Primary purpose: Diagnostic

Allocation: Randomized

Interventional model: Sequential Assignment

Masking: None (Open label)

---

14,400 participants in 2 patient groups

AI-Assisted Diagnosis

Experimental group

Description:

Patients in this group will undergo head CTA, interpreted by radiologists with the assistance of a previously validated deep learning AI model. The model highlights suspected aneurysm candidates on the CTA images to support diagnostic decision-making.

Treatment:

Device: AI-Assisted CTA Interpretation

Standard Diagnosis

Active Comparator group

Description:

Patients in this group will undergo head CTA, which will be interpreted by radiologists following standard local diagnostic protocols. No AI assistance will be provided during image interpretation.

Treatment:

Diagnostic Test: Standard CTA Interpretation