An epidural steroid injection places this powerful anti-inflammatory medication directly around the spinal nerves. Traditionally epidural injections were administered without any special equipment, by inserting the needle by feel in the area around the spinal nerves. More recently epidural injections have been administered with the aid of imaging tools to allow your physician to see the needle going to the proper location. Either real-time x-ray called fluoroscopy, or CT scan can be used to 'watch' the needle deliver the medication to the proper location.
The needle is smaller in size than that used during a conventional epidural approach. The procedure is performed with the patient lying on their belly using fluoroscopic (real-time x-ray) guidance, which helps to prevent damage to the nerve root. A radiopaque dye is injected to enhance the fluoroscopic images and to confirm that the needle is properly placed (See Figure 2). This technique allows the glucocorticoid medicine to be placed closer to the irritated nerve root than using conventional interlaminar epidural approach. The exposure to radiation is minimal.