Evaluation of vascular complication incidence in patients with Internal Carotid Artery(ICA) stenosis treated with Carotid Artery Stenting (CAS) without Embolic protection device (EPD) in comparison to CAS with EPD

To determine complications of carotid artery stenting without the use of embolic protective device compared to usage of embolic protective device in patients with carotid artery stenosis

A single-blinded parallel randomized Clinical trial with control group is performed on 60 patients using block randomization (10 blocks of 6)

In this study, patients with carotid artery stenosis who are candidates for carotid artery stenting, will be treated in two groups: in the first group carotid artery stenting is done using embolic protective device and in the second group without embolic protective device. For all patients, brain magnetic resonance imaging (MRI) including diffusion-weighted imaging before and early (24 hours) after the procedure is performed. then, patients are examined 24 hours and 2 years after the procedure regarding probable complications. The single blind method is used, so that the evaluation team who assess the results of the intervention (including the physician who examines the patients before and after the treatment to evaluate the results of the intervention and the radiologist who reviews patients MRI) are blinded to the type of the study.

Inclusion criteria: Patients over 18 years old, Carotid artery stenosis more than 70% in asymptomatic patients, Carotid artery stenosis more than 50% in symptomatic patients. Exclusion criteria: Ideal candidates for carotid Endarterectomy, Renal failure, history of allergy to radiocontrast agents.

Intervention group: The group treated with carotid artery stenting using embolic protection device (Type: EZ, Manufacturer: Boston Scientific). Control group: The group treated with carotid artery stenting without using embolic protection device

Neurological complications including stroke symptoms; restenosis of carotid artery

In this study, we will use the restricted randomization method of the block randomization type. Blocking is usually used in order to balance the number of samples allocated to each of the study groups. This feature allows researchers to assign the same number of samples to each of the examined groups in circumstances where intermediate analyses are required during taking samples. The size of all the blocks is equal and will be 6 in this two-group experiment (including 3 participants in the intervention group and 3 participants in the control group). Additionally, random allocation software is used to generate random sequences using the block approach in addition to simple randomization. To conceal the random allocation, we utilize allocation concealment, which refers to the method of performing a random sequence on the research participants in such a way that the allocated group is unknown prior to the allocation of the individual. Using opaque letter envelopes sealed with a random sequence, each random sequence formed is recorded on a card, and the cards are placed inside the letter envelopes in the order they are inserted. To preserve a random sequence, the exterior surface of the envelopes is numbered in the same order. The letter envelope lids are then sealed with adhesive and set within a box. At the time of participant registration, one of the envelopes will be opened, revealing the individual's assigned group depending on the sequence in which the eligible participants entered the study.

In this single-blinded study, the evaluation team who assess outcomes (Including the physician who examines the patients before and after the treatment to evaluate the intervention results and the radiologist who reviews MRI results) are blinded to the type of the treatment. In fact, the outcome evaluation team is not part of the treatment team and only evaluates the procedure outcome.