MRI Protocol for Peripheral Neuropathy of Both Hands
For peripheral neuropathy affecting both hands, request a dedicated MRI of the brachial plexus bilaterally with MR neurography sequences, NOT a standard wrist or hand MRI. This should include high-resolution T2-weighted sequences with fat suppression, T1-weighted sequences in orthogonal planes through the oblique course of the plexus, and consideration of diffusion-weighted imaging for optimal nerve visualization 1.
Why Dedicated Plexus Imaging is Critical
Standard wrist or hand MRI protocols are insufficient for evaluating peripheral neuropathy because they lack the specialized sequences and field-of-view needed to assess the entire nerve pathway from the cervical spine through the brachial plexus to the distal upper extremity 2, 1. The key distinction is that plexus imaging differs fundamentally from routine neck, chest, or extremity MRI—it requires orthogonal views through the oblique planes of the plexus with specific nerve-optimized sequences 1.
Essential Technical Specifications
The MRI protocol should include:
- High-resolution T2-weighted sequences (the workhorse sequence for nerve imaging) 3
- Fat-saturated T2-weighted or STIR sequences to highlight nerve signal abnormalities 2, 1
- T1-weighted sequences in sagittal and axial planes to assess anatomy and identify compressive lesions 4, 1
- 3.0 Tesla magnet system preferred for optimal resolution, though 1.5T is acceptable if metal artifact is a concern 2, 1
- Isotropic voxel acquisition when possible for multiplanar reformatting 1
Advanced Sequences to Consider
Diffusion-weighted MR neurography (DW-MRN) provides superior visualization of small nerves in the wrist and palm compared to standard sequences and should be specifically requested if available 5. This technique has been validated for improved detection of median and ulnar nerve pathology and their small branches in the hand 5.
Contrast Administration Decision Tree
Gadolinium-based contrast is NOT routinely necessary for evaluating peripheral neuropathy unless:
- You suspect an intrinsic nerve tumor (schwannoma, neurofibroma, malignant peripheral nerve sheath tumor) 2
- Inflammatory plexopathy (brachial neuritis) is in the differential 4
- You need to differentiate between post-treatment changes and recurrent tumor 2
If contrast is used, fat-saturated T1-weighted post-contrast sequences should be added 2, 1. Macrocyclic agents are preferred to minimize gadolinium deposition risk 6.
What the Radiologist Should Evaluate
On the MR neurography images, abnormal nerves will demonstrate:
- Increased T2 signal (hyperintense relative to muscle) 3, 7
- Nerve thickening or caliber changes 3, 7
- Loss of normal fascicular architecture (the "honeycomb" pattern should be preserved in normal nerves) 3, 7
- Denervation changes in muscles (T2 hyperintensity in acute phase, fatty atrophy in chronic phase) 2
Common Pitfalls to Avoid
Do NOT order "MRI wrist" or "MRI hand"—these standard protocols lack the nerve-specific sequences and extended field-of-view needed for neuropathy evaluation 2, 1
Bilateral imaging is essential for comparison, as subtle nerve signal changes are best appreciated when comparing to the contralateral side 1
If the institution cannot perform dedicated plexus MR neurography, ultrasound by an experienced operator is a reasonable alternative for median and ulnar nerve assessment at the wrist level, though it cannot evaluate the entire nerve pathway 8, 9
Electrodiagnostic studies should complement, not replace, imaging—they provide functional information but cannot localize structural lesions or characterize masses 10, 11
Specific Order Language
Request: "MRI brachial plexus bilateral with MR neurography protocol including high-resolution T2-weighted fat-saturated sequences, T1-weighted sequences in orthogonal planes, and diffusion-weighted imaging if available. Field of view should extend from cervical spine through distal forearm to capture entire nerve pathway."
This ensures the radiologist understands you need specialized nerve imaging, not a routine extremity study 1, 12.