A study approximately 20 years ago showed that without fluoroscopy, which is a real-time form of x-ray, doctors often missed their mark with the needle about 40% of the time (Renfrew et al, AJNR Am J Neuroradiol1991) . This is unfortunate as it becomes a disservice to a patient who is in extreme pain from sciatica, and the steroid medication was not being placed in the right spot four out of ten times. So more and more, the standard of care is for a pain management doctor to use fluoroscopy to ensure the most accurate needle placement possible for the epidural injection.
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.