Contrast spread technique.

Abstract

Dear Editor: Loss Of Resistance (LOR) technique (Dogliotti's principle) is well known and widely used, and so is Contrast Spread (CS) technique. This is what Dr. Donald L. Renfrew wrote in his description of how to perform cervical and thoracic epidural steroid injections, with the help of fluoroscopy, more than a decade ago: “When the needle is just behind the spinal canal inject 0.2 to 0.3 mL of nonionic contrast material and confirm position in the posterior soft tissues. Advance the needle very slowly with one hand while pressurizing the syringe (LOR) with the other. When a thin line of CSs along the posterior epidural space, immediately stop advancing the needle!” CS technique is intuitively used by many Pain Practitioners to identify epidural space, together with LOR technique, especially with cervical epidurals. However, LOR technique is not as reliable in the upper spine as it is in the lower spine as: 1. The ligamentum flavum is not fused at midline up to 60–70%, thus increasing the risk of …