Extra-axial cranial nerve enhancement: a pattern-based approach

Area of Science:

• Radiology
• Neuroimaging
• Medical Diagnostics

Background:

• Cranial nerve enhancement on MRI is a frequent yet complex diagnostic challenge.
• Existing literature often focuses on pathologies rather than a radiologist-centric, finding-first approach.
• A systematic method is needed to navigate differential diagnoses from observed MRI patterns.

Purpose of the Study:

• To develop and present a novel, practical pattern-based approach for diagnosing cranial nerve enhancement.
• To guide radiologists from specific MRI findings to accurate diagnoses.
• To offer a reverse approach starting with radiological evidence.

Main Methods:

• Literature review to identify key patterns of cranial nerve enhancement.
• Categorization of pathologies into four distinct patterns: unilateral linear, bilateral linear, unilateral thickened, and bilateral thickened.
• Inclusion of high-quality MRI images and illustrative panels for each pattern.

Main Results:

• Identification and definition of four primary patterns of cranial nerve enhancement.
• Description of the pathogenic origins and radiological features for each pattern.
• Provision of a recommended MRI protocol for evaluating cranial nerve enhancement.

Conclusions:

• The proposed pattern-based approach simplifies the diagnosis of cranial nerve enhancement.
• This method provides an immediately applicable tool for clinical practice.
• It effectively translates challenging MRI findings into specific pathological patterns.