Beyond the brain: Extra-axial pathology on diffusion weighted imaging in neuroimaging

Area of Science:

• Radiology and Medical Imaging
• Neuroimaging
• Head and Neck Imaging

Background:

• Diffusion-weighted imaging (DWI) is a cornerstone in evaluating acute stroke and brain parenchyma abnormalities.
• Conventional brain imaging primarily focuses on intra-axial structures, often overlooking extra-axial components.

Purpose of the Study:

• To illustrate the added diagnostic value of DWI in assessing extra-axial head and neck structures.
• To showcase the utility of DWI in a wide spectrum of pathologies affecting vasculature, skull, orbits, nasal cavity, and salivary glands.
• To emphasize the necessity of reviewing all intra- and extra-axial structures on DWI.

Main Methods:

• Pictorial review format.
• Illustrative examples of various pathologies affecting head and neck structures using DWI.
• Comparison of DWI findings with conventional imaging sequences.

Main Results:

• DWI provides critical information for diagnosing disorders in the vasculature, skull, orbits, nasal cavity, and salivary glands.
• The review demonstrates specific cases where DWI reveals pathologies not evident on conventional sequences.
• Findings underscore DWI's sensitivity in detecting abnormalities in both intra-axial and extra-axial compartments.

Conclusions:

• DWI's application extends significantly beyond acute stroke, offering crucial insights into diverse head and neck pathologies.
• Routine brain imaging protocols should incorporate a thorough review of extra-axial structures on DWI.
• Radiologists must be vigilant in assessing all anatomical regions on DWI for comprehensive diagnosis.