FLAIR hyperintensity in the subarachnoid space: Main differentials.

Area of Science:

• Neuroimaging
• Radiology
• Medical Diagnostics

Background:

• Fluid-attenuated inversion recovery (FLAIR) is a crucial brain MRI sequence.
• FLAIR suppresses cerebrospinal fluid signal, aiding subarachnoid space disease detection.
• Hyperintensity in the arachnoid space on FLAIR can be pathological or artifactual.

Purpose of the Study:

• To differentiate between pathological and artifactual causes of arachnoid space hyperintensity on FLAIR MRI.
• To highlight the potential for diagnostic errors due to non-pathological FLAIR findings.
• To provide a comprehensive overview of conditions causing FLAIR hyperintensity.

Main Methods:

• Review of existing literature on FLAIR MRI findings.
• Analysis of cases presenting with arachnoid space hyperintensity.
• Categorization of hyperintensity causes into disease-related and artifact-related.

Main Results:

• Known causes of hyperintensity include tumors, inflammation, vascular disease, and CSF cellularity.
• Numerous non-pathological conditions, primarily artifacts, also cause hyperintensity.
• Artifacts represent a significant source of potential misdiagnosis.

Conclusions:

• Understanding the differential diagnosis of FLAIR hyperintensity is critical.
• Distinguishing between true pathology and artifacts is essential for accurate brain MRI interpretation.
• Awareness of artifactual causes can prevent unnecessary patient anxiety and interventions.