Interest in the possible rôle of the sympathetic nervous system in the production or transmission of painful sensations in the face was aroused by the failure of therapeutic measures, directed against the trigeminal nerve, to afford relief in cases of so-called atypical neuralgia. This group is ill defined and undoubtedly includes painful conditions of diverse origin. It is also probable that the different sensations of pain are transmitted over different nerves. In this paper I have attempted to indicate one type, those possibly of trigeminal tract origin, which may be separated from the group of atypical neuralgias.
The symptomatology of the so-called atypical neuralgias is characterized by its diversity, probably because no one has been able to distinguish the various types. Certain characteristics, however, are common to the majority of cases. The pain is generally described as a dull, aching, burning or pressure pain with exacerbations of greater intensity. Glaser