How much longer will the MRI scan take if the face, orbits, and neck are added to the protocol?

MRI Scan Time Extension for Face, Orbits, and Neck

Adding face, orbits, and neck imaging to a standard MRI brain protocol will extend the total scan time by approximately 10-15 minutes, though this can be performed simultaneously with head imaging rather than sequentially, potentially minimizing the actual time increase.

Expected Time Addition

The American College of Radiology guidelines consistently recommend that MRI orbit, face, and neck be performed "in conjunction with" MRI head for cranial neuropathy evaluation, indicating these are complementary studies that can be acquired in the same imaging session 1. Based on whole-body MRI protocols, a comprehensive head-to-pelvis scan requires 30-40 minutes 1.

Practical Time Estimates

• Standard MRI brain alone: Typically 20-25 minutes for a complete protocol
• Adding orbits, face, and neck sequences: Adds approximately 10-15 minutes to the total examination time 1
• Total combined examination time: Approximately 30-40 minutes for head through neck coverage 1

Technical Considerations Affecting Scan Time

Coil Configuration Impact

• Surface coils compatible with head/neck coverage provide superior signal-to-noise ratios (3-5 times higher than standard body coils) and can reduce the number of signal averages needed, potentially shortening acquisition time 2
• Flexible array coil arrangements (such as UltraFlexLarge18 configurations) demonstrate significantly better image quality parameters than smaller coil setups, which may allow for faster sequences without quality compromise 3

Modern Sequence Optimization

• 3D T1-weighted sequences with isotropic resolution can reduce face and neck protocol time by approximately 9-10 minutes (37-41% reduction) compared to traditional 2D acquisitions, while maintaining or improving spatial resolution 4
• High-resolution protocols (0.4 × 0.4 × 4 mm³) for face and neck can be completed in approximately 4 minutes per sequence using optimized surface coils 2
• Golden-angle radial sparse parallel (GRASP) sequences achieve both high temporal (2.5 seconds) and spatial resolution (0.94 × 0.94 × 3.00 mm) simultaneously, potentially replacing multiple conventional sequences and saving examination time 5

Protocol-Specific Recommendations

For Cranial Neuropathy Evaluation

The ACR rates MRI orbit, face, and neck without and with IV contrast as "usually appropriate" (rating 8-9) when performed in conjunction with MRI head for most cranial nerve pathologies 1. This combined protocol requires:

• Pre-contrast sequences: Approximately 15-20 minutes for head through neck
• Contrast administration and post-contrast sequences: Additional 15-20 minutes
• Total time with contrast: 30-40 minutes 1

Thin-Cut High-Resolution Requirements

• Thin-section sequences focused on specific anatomic regions (posterior fossa, skull base, facial nerve course) are essential for optimal visualization and should be specified in the protocol 6, 7
• These specialized sequences may add 3-5 minutes per anatomic region but are necessary for adequate diagnostic quality 6

Common Pitfalls to Avoid

• Sequential rather than simultaneous acquisition: Ordering separate "MRI brain" and "MRI face/neck" studies performed at different times doubles patient positioning time and overall examination duration
• Inadequate coil selection: Using body coils or standard head coils instead of dedicated surface coils for neck coverage significantly degrades image quality and may necessitate repeat imaging 2
• Motion artifacts: Extended scan times (>40 minutes) substantially increase the risk of motion degradation, particularly in patients with discomfort or claustrophobia 2
• Omitting contrast when indicated: The ACR emphasizes that pre- and post-contrast imaging provides the best opportunity to identify and characterize lesions along cranial nerve pathways, and omitting contrast may necessitate callback for additional imaging 6