The Effect of Ultrasound Guidance on Radiation Dose and Procedure Time in Lumbar Transforaminal Epidural Injection

The patients are positioned prone. The injection site is cleaned with povidone-iodine 3 times and a sterile drape was applied. Short-acting local anesthesia (3 mL of 2% prilocaine) is applied to the skin and subcutaneous tissue. A 3.5-inch, 22-gauge spinal needle is inserted just below the pedicle. It is advanced into the subpedicular space using the coaxial technique under the intermittent guidance of fluoroscopy. The needle position is confirmed through a lateral view. Using lateral views, the needle is placed at the posterior one-third of the foramen. Using the anteroposterior view, one to 2 mL of the contrast agent (300 mg/50 mL iohexol) is given and the distribution pattern is visualized. Once the epidural distribution of the contrast agent is confirmed without vascular flow, a mixture of 8 mg (two mL) of dexamethasone, 1 mL of physiological saline, and 1 mL (0.5%) of bupivacaine hydrochloride is injected.

The patients are positioned prone placed. Following the provision of aseptic conditions, the spinous process of the vertebral midline is visualized using a low-frequency convex ultrasound probe. The lateral edge of the relevant vertebral lamina is visualized by sonographic scanning in the horizontal plane. Local anesthesia is applied to the skin and subcutaneous tissue. A 3.5-inch, 22-gauge spinal needle is advanced to the lateral edge of the relevant vertebral lamina under ultrasound image guidance. Then, anteroposterior imaging is performed with fluoroscopy to confirm needle localization when the lamina margin is reached, and the needle is guided into the foramen under the guidance of fluoroscopy. The contrast agent is given and the distribution pattern is visualized. Once the epidural distribution of the contrast agent is confirmed without vascular flow, a mixture of 2 mL of dexamethasone, 1 mL of physiological saline, and 1 mL (0.5%) of bupivacaine hydrochloride is injected.