What is Sluder's neuralgia?

In 1908 Sluder described a symptom complex consisting of neuralgic, motor, sensory and gustatory manifestations that he attributed to the sphenopalatine ganglion. He stated that treatment directed at the ganglion successfully alleviated these symptoms. Over the last 90 years several reports have described patients as having sphenopalatine neuralgia and have directed treatment at the ganglion. The symptoms described and the criteria for patient selection in these studies has often been varied and deviated from Sluder's description. In reports claiming cures with treatment directed at the ganglion the duration of post-treatment follow-up has been short. This article discusses Sluder's description and attempts to analyse its features in the light of current understanding of the different mechanisms and categories of facial pain. It is proposed that the condition described by Sluder is a neurovascular headache that most closely resembles cluster headache in its aetiology and clinical manifestations. We propose that the term Sluder's neuralgia should be discarded as there are serious flaws in its original description and many authors have misused the term leading to persistent confusion about it.