The pterygopalatine ganglion (PPG), often described as the Piccadilly Circus of the Face, is of great importance to anesthesiologists, pain physicians, neurologists and surgeons, and its blockade is becoming more and more popular as our understanding of the cholinergic mechanisms of headache improve. It is also known as the sphenopalatine ganglion, Meckel's ganglion or the Nasal ganglion. Recent publications have shed important light on the neuroanatomy...