Ho KWD, et al. - Researchers planned the systematic review to collect and summarize the level of evidence supporting the use of sphenopalatine ganglion block, radiofrequency ablation and neurostimulation. For treating cluster headache, sphenopalatine ganglion seemed a promising target using blocks, radiofrequency ablation and neurostimulation. Some evidence, supporting sphenopalatine ganglion block use, have also been recognized in a few other conditions.