Evaluation of accelerated sampling techniques for vessel wall imaging

Specific Aim 1: To image the intracranial artery vessel walls (brain), we will evaluate and compare scans acquired using standard-of-care T1 SPACE and T1 MPRAGE sequences with novel accelerated pulse sequences in patients with suspected intracranial vasculopathy.

Specific Aim 2: To image the extracranial artery vessel walls (neck). We will evaluate and compare the scans acquired using standard-of-care T1 SPACE and T1 MPRAGE sequences with novel accelerated pulse sequences for patients with suspected extracranial vasculopathy. The outcome variable of this study will be measured after the clinical read and will not impact the clinical decisions. The primary outcome of the study will be the raters study where qualitative imaging scores will be provided by experienced radiologists using a four-point scale [1].

Score 1: Vessel wall not seen clearly; poor image quality. Score 2: Vessel wall seen in part; diagnostic image quality. Score 3: Vessel wall seen clearly in most parts; good image quality. Score 4: Sharp vessel wall confidently delineated; excellent image quality. The secondary outcome variable of this study will also be measured after the clinical read and will not impact the clinical decisions. The secondary outcome variable will be quantitative validation. Firstly, the lumen and outer wall boundaries in all of the acquired pulse sequences will be computed using a 3D segmentation tool, such as Osirix.

The following will be measured for the circle of Willis (brain) and carotid artery (neck) vessels:

        -vessel lumen area 
        -wall area 
        -wall to lumen contrast ratio (CR wall/lumen = signal of wall/signal of lumen)
        -contrast enhancement ratio 

Area measurements from the novel accelerated pulse sequences will be compared with standard-of-care T1 SPACE and T1 MPRAGE pulse sequences. The protocol with best agreement and highest CR (contrast ratio) of the wall/lumen will be determined.

You may be eligible for this study if you meet the following criteria:

• Conditions:
  Medical Research
• Age: - 99 Years
• Gender: All