Evaluation of the Safety and Efficacy of Stenting for Chronic Middle Cerebral Artery Occlusion With Limb Dysfunction: a Prospective Study
Phase: EARLY_PHASE1
Conditions: Chronic Middle Cerebral Artery Occlusion, Stenting Treatment, Modified Rankin Scale, National Institutes of Health Stroke Scale
Sponsor: Huizhou Municipal Central Hospital

 
Study Protocol Document 
 
 
 
 
 
 
 
 
Research Official 
Title: 
A Prospective Study on Safety and Efficacy 
of Stenting for Chronic Middle Cerebral 
Artery Occlusion With Limb Dysfunction 
Filedate: 
March 1, 2021 
 
 
 

A prospective study on the safety and efficacy of 
stent placement in the treatment of chronic middle 
cerebral artery occlusion with limb dysfunction 
 
I. Research Background 
The middle cerebral artery (MCA) is one of the main blood vessels that supply most areas of 
the cerebral cortex. When chronic occlusion occurs in MCA, it seriously affects blood flow to 
multiple important areas of the brain, including areas that control speech, sensation, and motor 
function. Therefore, MCA occlusion is often associated with severe neurological deficits such 
as hemiplegia, speech impairment, and cognitive impairment. Chronic MCA occlusion is 
usually caused by intracranial atherosclerosis, a procession in which the arterial wall gradually 
accumulates fat and calcium, leading to narrowing of the vessel. When blood vessels narrow to 
a certain extent, blood flow is reduced to a level that is insufficient to meet the needs of brain 
tissue, which can result in ischemic brain injury. Studies have shown that hypertension and 
diabetes are the main risk factors for intracranial stenosis and chronic MCA occlusion. These 
conditions increase the risk of MCA occlusion by accelerating the process of atherosclerosis, 
increasing the thickness and stiffness of blood vessel walls. In addition, smoking is another 
important controllable risk factor, which increases the risk of atherosclerosis by damaging 
vascular endothelial function and promoting inflammatory reaction. 
Although there has been sufficient research on acute MCA occlusion, including vascular 
recanalization protocols during the acute phase, such as thrombolysis and mechanical 
thrombectomy, there is limited research on chronic MCA occlusion. Due to the long-term and 
complex nature of the disease course, the treatment strategies and prognosis evaluation for 
patients in the chronic phase are not yet clear. In addition, for patients who have not received 
timely or ineffective acute treatment, how to improve their long-term prognosis through 
interventional treatment is a major challenge in current research. 
Previous case reports and retrospective studies have shown that even after years of MCA 

occlusion, vascular reconstruction surgery can still successfully restore blood flow and achieve 
good therapeutic effects. However, currently, the vascular reconstruction treatment for chronic 
MCA occlusion is mainly limited to case reports, and there is a lack of systematic prospective 
studies to verify the safety and effectiveness of these treatments. 
Given the above background, this study aims to fill this research gap by systematically 
evaluating the efficacy and safety of stent placement in patients with chronic MCA occlusion 
through prospective clinical trials, in order to provide more scientific and standardized 
treatment guidance for such patients. 
 
II. Research Purpose 
The aim of this study is to evaluate the safety and effectiveness of stent placement in patients 
with chronic MCA occlusion, and to explore its impact on blood flow recovery, reduction of 
reocclusion rate, and improvement of neurological function recovery. 
 
III. Research Methodology 
1. Research Design 
This study adopts a prospective, single center, observational clinical trial design. By setting up 
a stent group and a control group, the therapeutic effects of the two groups of patients were 
compared to evaluate the safety and effectiveness of stent placement in patients with chronic 
middle cerebral artery (MCA) occlusion. This study has been approved by the Clinical Ethics 
Committee of Huishou Central People's Hospital in terms of human research ethics, and strictly 
adheres to relevant ethical standards and guiding principles. 
 

2. Study Participants 
Selection Criteria: 
1） Age 18 and above, male and female unlimited. 
2） Chronic occlusion of MCAconfirmed by magnetic resonance imaging (MRI) or 
computed tomography (CT), lasting more than 3 months. 
3） Neurological deficits caused by MCA occlusion, such as hemiplegia, speech disorders, 
etc. 
4） Have not received MCA stent revascularization treatment in the past three months. 
Exclusion Criteria: 
1） Acute stroke occurred within the past three months. 
2） Severe heart disease, liver and kidney dysfunction, cerebral hemorrhage, active bleeding, 
or coagulation dysfunction. 
3） Allergy to contrast agents. 
4） Serious mental illness or inability to comply with research requirements. 
5） Pregnant or lactating women. 
6） MCA occlusion was found without any symptoms. 
7） Participated in other clinical trials within the past six months. 
 
3. Research Process 
Participants first undergo detailed screening to ensure that they meet the inclusion and exclusion 

criteria. Afterwards, all patients or their legal representatives are required to sign an informed 
consent form. Subsequently, patients will be randomly assigned to either the stent group or the 
control group. The control group received aspirin treatment, while the stent group underwent 
stent placement surgery on the basis of aspirin treatment. 
 
4. Stenting Method 
The patient underwent whole brain angiography in the intervention room, and the Seldinger 
technique was successfully used to puncture the right femoral artery and insert a 5F sheath. 
Insert the 5F pigtail catheter and vertebral artery catheter sequentially through the sheath tube 
for angiography to identify occlusion of left or right MCA. Next, the MCA stent is inserted, 
and the 0.014-inch microwire and microcatheter are successfully navigated to the left or right 
MCA occlusion site through the catheter. Then, the microcatheter is exchanged, and an 
appropriately sized intracranial self expanding stent is placed and released. After surgery, the 
femoral artery puncture site was sutured using a vascular closure device. 
 
IV. Statistical Analysis 
Use R software (version 4.1.2) for statistical processing.Classifieddatais presented in frequency 
and percentage, while continuous data is represented in mean ± standard deviation or median 
and interquartile range. Inter group comparisons were conducted using methods such as 
independent sample t-test, Mann Whitney U test, chi square test, or Fisher's exact test. 
 
V. Research Plan 
Preparation phase (March 2021- April 2021): Obtain ethical approval, prepare and review 
all research documents (including informed consent forms and research protocols), and 

establish a data management system. 
Recruitment stage (May2021 November 2021): Identify eligible patients through the 
neurology and interventional radiology departments of collaborating hospitals, screen for 
inclusion and exclusion criteria, and obtain informed consent from patients. 
Treatment stage (December 2021- January 2022): Arrange stent placement surgery or start 
standard drug treatment for eligible patients. 
Follow up stage (February 2022- February 2023): Regular follow-up will beconducted on 
all participants to evaluate treatment outcomes, including blood flow recovery, reocclusion rate, 
and neurological function recovery. The follow-up time points is 3 months after surgery. 
Data analysis stage (March 2023 September 2023): Collect all data, conduct statistical 
analysis, compare the differences between the two groups, and write a research report.