The anatomy of posterior aspect of neuroforamina shows 21 arterial branches. Out of 21, 7 are segmental medullary vessels running in the spinal cord. Moreover, there is rich anastomosses between cervical and vertebral arteries. These arteries are at a risk of injury by transforaminal ESI. In order to prevent artery damage during transforaminal ESIs; 1. Use live-time fluoroscopy to present intravascular injections by clear visualization of vessels 2. Use Digital Subtraction Angiography (DSA) to choose a better venous flow.