What is better for assessing vertebral arteries before injections for craniocervical instability, Cone Beam Computed Tomography (CBCT) or Magnetic Resonance Elastography (MRE)?

From the Guidelines

MRA is the preferred imaging modality for assessing vertebral arteries before injections for craniocervical instability, as it provides high-resolution images of the cervical arteries without radiation exposure and has high sensitivity for detecting vascular abnormalities. According to the most recent and highest quality study 1, CTA has the highest reported sensitivity for detecting vertebral artery dissection, but MRA is also a highly sensitive modality for evaluating the cervical arteries. The study notes that MRA can generate high-resolution noninvasive images of the cervical arteries, and technological advancements have improved the quality of MRA to rival that of conventional angiography.

Some key points to consider when choosing an imaging modality for assessing vertebral arteries include:

• The need for high-resolution images of the cervical arteries
• The importance of avoiding radiation exposure
• The sensitivity of the modality for detecting vascular abnormalities
• The ability of the modality to visualize the course of the vertebral arteries through the transverse foramina of the cervical spine

In contrast, Cone Beam Computed Tomography (CBCT) offers excellent bone detail but has limitations in soft tissue contrast, which is necessary for optimal vessel visualization. Magnetic Resonance Elastography (MRE) is not typically used for vascular assessment, as it is designed to measure tissue stiffness rather than visualize blood vessels.

Before cervical injections in craniocervical instability cases, proper vascular imaging is crucial to avoid inadvertent injury to the vertebral arteries, which could lead to serious complications including stroke. The radiologist should be informed about the specific clinical concern of craniocervical instability to ensure appropriate imaging protocols are used to visualize the course of the vertebral arteries through the transverse foramina of the cervical spine.

It is also important to note that the choice of imaging modality may depend on the specific clinical context and the availability of imaging modalities at the institution. However, based on the available evidence, MRA is the preferred imaging modality for assessing vertebral arteries before injections for craniocervical instability.

From the Research

Assessment of Vertebral Arteries

To assess vertebral arteries before injections for craniocervical instability, the choice between Cone Beam Computed Tomography (CBCT) and Magnetic Resonance Elastography (MRE) depends on various factors.

• CBCT has been shown to be useful in evaluating the detailed structures of vertebral artery dissection 2 and in visualizing perforators in vertebral artery dissection 3.
• CBCT angiography can provide high-resolution images of the vertebral arteries and their relationship to the surrounding bony anatomy 4, 5.
• There is no direct comparison between CBCT and MRE in the provided studies, but CBCT has been compared to other imaging modalities such as catheter-based angiography, CT angiography, and MRI, and has been found to be superior in detecting certain features of vertebral artery dissection 2.
• The use of CBCT in assessing vertebral arteries is supported by studies that highlight its ability to provide detailed luminal and wall morphology of vertebral artery dissections 2 and its efficacy in evaluating perforators in vertebral artery dissection 3.

Limitations of the Studies

• The provided studies do not directly compare CBCT and MRE, making it difficult to determine which modality is better for assessing vertebral arteries before injections for craniocervical instability.
• The studies focus on the use of CBCT in evaluating vertebral artery dissection and its complications, rather than its use in assessing vertebral arteries before injections for craniocervical instability.
• More research is needed to determine the optimal imaging modality for assessing vertebral arteries before injections for craniocervical instability.

Key Findings

• CBCT is a useful modality for evaluating vertebral artery dissection and its complications 2, 3.
• CBCT angiography can provide high-resolution images of the vertebral arteries and their relationship to the surrounding bony anatomy 4, 5.
• The choice of imaging modality depends on the specific clinical question and the patient's individual characteristics.