Radiology
MRI uses strong magnetic fields to align atomic nuclei (usually hydrogen protons) within body tissues, then uses a radio signal to disturb the axis of rotation of these nuclei and observes the radio frequency signal generated as the nuclei return to their baseline states. The radio signals are collected by small antennae, called coils, placed near the area of interest. An advantage of MRI is its ability to produce images in axial, coronal, sagittal and multiple oblique planes with equal ease. MRI scans give the best soft tissue contrast of all the imaging modalities. With advances in scanning speed and spatial resolution, and improvements in computer 3D algorithms and hardware, MRI has become an important tool in musculoskeletal radiology and neuroradiology.
Laminotomy
Since an MRI provides excellent imaging of blood vessels and tissues, it is recognized as the best type of imaging to observe signs associated with lumbar compression. The precise measurement of the diameter of the spinal canal is a particularly important component when determining the severity of the stenosis itself. High strength 3-Tesla MRI machines are being utilized due to the increased vascular imaging capabilities. Better resolution capacity allows for more detailed observations by the healthcare provider. The sharp contrast of the high power MRI outlines details in the vertebra that are critical when examining a patient with lumbar spinal stenosis who may need a laminotomy. MRI scanning post invasive surgery is used to see the quality of the surgery itself, yet the appropriate postoperative time elapsed before conducting an MRI is a debated topic.