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First image demonstrates planning with the projected course to the posterior epidural space (fat density) and distance from a skin marker to the proposed skin entry site for marking.

Second image shows the spinal needle in-plane with the tip at the ligamentum flavum.

Third images is post air release technique with the needle tip in the epidural space confirmed by the presence of air in the epidural space. Subsequently 4 mg dexamethasone and 1 mL 1% lidocaine was inj