NERVE ULTRASOUND

Yes — high-resolution ultrasound can visualize many peripheral nerve problems (entrapment, compression, traumatic injury, neuromas, and cysts), measure focal swelling, and often guide procedures. It’s real-time, portable, and complements electrodiagnostic testing and MRI. Limitations: poor visualization of deep or central nerves, insensitivity for small‑fiber or diffuse metabolic neuropathies, and operator dependence.

Ultrasound can both diagnose and assist treatment of peripheral nerve injury. High-resolution ultrasound reliably visualizes nerve compression, tears, neuromas and guides injections or hydrodissection. Therapeutic ultrasound and ultrasound-guided procedures may reduce pain and improve function in some entrapment injuries, but evidence for accelerating true nerve regeneration is limited. A clinician can advise whether ultrasound-based diagnosis or interventions are appropriate.

MRI is the primary imaging test for detecting structural nerve damage—especially MR neurography, which visualizes peripheral nerves and surrounding tissues. High-resolution ultrasound can image superficial peripheral nerve lesions. CT myelography helps identify nerve-root compression in the spine. Note: electromyography (EMG) and nerve conduction studies aren’t scans but are essential tests that detect functional nerve injury and localization.

MRI is generally better for nerve pain originating from the spine or deep structures because it visualizes nerve roots, discs, and soft tissues in high detail. Ultrasound is useful for superficial peripheral nerves, dynamic assessment, and ultrasound-guided injections; it’s cheaper and portable. The optimal test depends on the suspected location and clinical question — MRI for central/deep causes, ultrasound for superficial nerves and procedural guidance.

Nerve conduction studies (NCS) and electromyography (EMG) are the primary tests to confirm peripheral nerve damage: NCS measures how fast and strongly signals travel along nerves, while EMG assesses muscle electrical activity to detect denervation. For structural causes, MRI or ultrasound can image nerve compression; skin biopsy or specialized sensory testing may be used for small‑fiber neuropathy.

Position the patient to expose the limb and relax muscles. Use a high-frequency linear transducer with ample gel. Scan the nerve in transverse and longitudinal planes, identifying hypoechoic fascicles within a hyperechoic sheath. Measure cross-sectional area, compare with the opposite side, and use Doppler for vascularity. Apply dynamic maneuvers if needed and document focal enlargement, compression, or discontinuity.