91 © Springer Nature Singapore Pte Ltd. 2019 G. P. Rath (ed.), Handbook of Trigeminal Neuralgia, https://doi.org/10.1007/978-981-13-2333-1_12 S. Chavali · G. P. Rath (*) Department of Neuroanaesthesiology and Critical Care Neurosciences Centre, All India Institute of Medical Sciences, New Delhi, India Infraorbital Nerve Block Siddharth Chavali and Girija Prasad Rath Introduction The infraorbital nerve is the terminal branch of the maxillary nerve. It may become entrapped at any point along the length of its course, usually as it exits the skull via the infraorbital foramen causing shock-like unilateral pain its distribution known as infraorbital neuralgia. The classical fndings of infraorbital neuralgia include (1) Pain over upper cheek radiating to upper teeth, nose and upper eyelid usually described as sharp, tingling or electric-like; (2) Tenderness to pressure over infraor- bital foramen with possible radiation of pain along the nerve distribution on the affected side; and (3) Symptoms may be exacerbated by smiling, laughing or exces- sive tension on the zygomatic muscles, possibly due to further compression of the infraorbital nerve. Key Points • Pain related to infraorbital neuralgia may be triggered by laughing or smil- ing due to compression on the infraorbital nerve • It is diffcult to diagnose infraorbital neuralgia which may be confused with maxillary sinusitis • If nerve block is unsuccessful a feld block with local anesthetic agent may be attempted