Prospective Randomized Controlled Trial of Surface-Modified Flow Diverter for Intracranial Aneurysms: Multicenter Assessment of Ischemic and Clinical Outcomes (PRISMATIC)

Flow diverters (FDs) have become a mainstay of endovascular therapy for unruptured intracranial aneurysms (UIAs), yet their implantation carries an inherent risk of ischemic complications. The Pipeline Flex Embolization Device with Shield Technology (PED Shield) and the Lattice Flow Diverter (LFD) are two surface-modified FDs that have shown promising efficacy for mitigating procedure-related ischemic events in prior single-arm or retrospective series. Nevertheless, head-to-head comparative data between these two surface-modified flow diverters remain scarce, and prospective randomized clinical trials are warranted to corroborate their differential performance in lowering ischemic complication risks.This prospective, multicenter randomized controlled trial (RCT) was designed to compare the efficacy of PED Shield versus LFD in reducing ischemic complications after endovascular treatment of UIAs. A total of 196 eligible participants who meet the predefined inclusion and exclusion criteria will be enrolled in the trial. The primary outcome measure is the incidence of new diffusion-weighted imaging (DWI)-positive lesions on brain magnetic resonance imaging (MRI) within 48 hours after the procedure. The secondary outcome measures consist of perioperative symptomatic ischemic events, all-cause mortality and disability rate during the follow-up period, delayed aneurysm rupture at the 6-month follow-up, complete aneurysm occlusion rate, incidence of major in-stent stenosis (stenosis degree >50%) at the 6-month follow-up, and the number of new DWI-positive lesions within 48 hours post-procedure.

Study Overview

• Status: Recruiting
• Conditions: Intracranial Aneurysms; Flow Diverter
• Intervention / Treatment: Device: PED Shield; Device: LFD

• Study Type: Interventional
• Enrollment (Estimated): 196
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Li Li, MD; Phone Number: +8615038063905; Email: lli120253@163.com

Study Locations

• China
  • Henan
    • Zhengzhou, Henan, China, 450000
      • Recruiting
      • Henan Provincial People's Hospital
      • Contact: Li Li, MD; Phone Number: +8615038063905; Email: lli120253@163.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Patients were diagnosed with unruptured intracranial aneurysms, and the lesions were evaluated to be suitable for endovascular treatment with flow diverter devices (PED Shield/Lattice).
2. During the study period, only one target aneurysm per patient was treated, with the exception of segmental lesions, in which multiple aneurysms located within the same arterial segment were treated with a single or overlapping study devices.
3. The target aneurysm was treated solely with flow diverter (FD) implantation in the current study.
4. The age of enrolled patients ranged from 18 to 75 years old.
5. Patients were capable of understanding the study-related informed consent information and provided written informed consent for the use of their clinical data for research purposes.

Exclusion Criteria:

1. Patients with a prior history of endovascular treatment for the target aneurysm.
2. Patients in the acute stage of cerebrovascular diseases (acute cerebral infarction or intracerebral hemorrhage with an onset time of ≤ 2 weeks).
3. Patients complicated with other cerebrovascular disorders, including moyamoya disease, cerebrovascular malformations, and arteriovenous fistula.
4. Patients with atherosclerotic changes in the parent artery of the target aneurysm that necessitated additional intraoperative endovascular interventions (e.g., balloon angioplasty or conventional stent implantation).
5. Patients with a preoperative modified Rankin Scale (mRS) score greater than 2.
6. Patients with any absolute contraindications to device treatment as specified in the Instructions for Use (IFU).
7. Patients enrolled in other clinical trials that may interfere with the primary or secondary endpoints of the present study.
8. Patients with comorbidities that may interfere with neurological function evaluation, affect survival status, or impair the ability to complete follow-up visits.
9. Pregnant or lactating female patients.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: PED Shield; Subjects Treated with the PED Shield for Intracranial Aneurysms	Device: PED Shield; Subjects who meet the inclusion and exclusion criteria will undergo randomization after signing the study informed consent form. When a subject is randomly assigned to the PED Shield group, the operator will implant this flow diverter following standardized surgical procedures.
Experimental: LFD; Subjects Treated with the LFD for Intracranial Aneurysms	Device: LFD; Subjects who meet the inclusion and exclusion criteria will undergo randomization after signing the study informed consent form. When a subject is randomly assigned to the LFD group, the operator will implant this flow diverter following standardized surgical procedures.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The incidence of patients with new positive diffusion-weighted imaging (DWI) lesions	The proportion of patients with newly developed DWI hyperintensities detected on magnetic resonance imaging (MRI) within 48 hours after the surgical procedure.	Within 48 Hours postoperatively.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Symptomatic neurological ischemic events	Symptomatic neurological ischemic events related to the target aneurysm, mainly including transient ischemic attack （TIA） and acute cerebral infarction, as adjudicated by the clinical event committee.	0-7 days postoperatively
Mortality and major disability rate during follow-up	Proportion of patients with a modified Rankin Scale (mRS) score > 3 or an increase of ≥ 2 points in mRS score from baseline, as adjudicated by the clinical event committee.	180 (±30) days
Rate of delayed aneurysm rupture	Incidence of intracranial hemorrhage caused by delayed rupture of the target aneurysm, as adjudicated by the clinical event committee. The time calculation starts from the first day after surgery.	180 (±30) days
Aneurysm complete occlusion rate	Complete occlusion rate of the target aneurysm assessed via the Raymond-Roy classification scale.	180 (±30) days
Incidence of target parent artery in-stent stenosis (>50%)	In-stent stenosis of the target parent artery was defined as stenosis degree >50%, which was evaluated by digital subtraction angiography (DSA), computed tomography angiography (CTA), or magnetic resonance angiography (MRA) at 6 months after surgery.	180 (±30) days
Number of DWI positive lesions	The number of DWI positive lesions detected on postoperative magnetic resonance imaging (MRI).	Within 48 hours postoperatively

Collaborators and Investigators

• Sponsor: Henan Provincial People's Hospital
• Collaborators: Chinese PLA General Hospital; Zhujiang Hospital; The First Affiliated Hospital of Henan University of Traditional Chinese Medicine; First Hospital of China Medical University; Yichang Central People's Hospital; Nanyang Central Hospital; Kaifeng Central Hospital; Handan Central Hospital; Shandong First Medical University; The First Affiliated Hospital of Henan Medical University

Study record dates

Study Major Dates

• Study Start (Actual): May 21, 2026
• Primary Completion (Estimated): February 28, 2027
• Study Completion (Estimated): September 30, 2027

Study Registration Dates

• First Submitted: June 23, 2026
• First Submitted That Met QC Criteria: June 23, 2026
• First Posted (Actual): June 29, 2026

Study Record Updates

• Last Update Posted (Actual): June 29, 2026
• Last Update Submitted That Met QC Criteria: June 23, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: intracranial aneurysms; flow dierters; surface-modified
• Additional Relevant MeSH Terms: Cerebrovascular Disorders; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Vascular Diseases; Cardiovascular Diseases; Intracranial Arterial Diseases; Aneurysm; Intracranial Aneurysm
• Other Study ID Numbers: 2025-234

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No