Spinal disc herniation (EDL) diagnostics
When is this exam indicated?
Standard radiographic (X-ray) examination is the primary examination to rule out other causes of acute pain. For patients with a typical clinical pattern, MRI is recommended within 4-6 weeks of conservative treatment. It is used on an urgent basis for cauda equina syndrome or spinal cord neurological disorders. It also plays a major role in atypical radiculopathies (pruriticular, aggravating, paralyzing, hyperlagic). The presence of disc herniation or protrusion or bulging in the absence of related symptoms has no pathological significance. Computed tomography (CT) is used in cases of radiculopathy caused by herniated discs, when MRI is contraindicated (pace-makers, metal implants, etc.) or is not feasible.
How is it performed?
The radiographic examination should be performed in two projections (AP and lateral), under pressure. The MRI is based on the use of a magnetic field and the patient, after signing the notified consent, is placed on a bed that is slid inside a cyclindrical structure, open at both ends. The examination lasts about 15-20 minutes. No special preparation of the patient is required. If the examination involves the use of contrast medium, it is necessary to exclude any allergies and provide a recent renal function test (creatinine). CT involves the use of X-rays projected at different angles in order to have detailed information about the area under examination from different angles. No special preparation is required. The patient is placed on a couch for the required time to acquire the image. It lasts about 10-15 min.
The main contraindications concern MRI: non-MRI compatible metals, metal pieces, dental prosthesis, pregnancy, pacemaker, intrauterine devices (IUD). In case of contrast medium use (both iodine for CT and gadolinium for MRI), rarely foreseen, the patient must follow an adequate anti-allergic preparation.