Gustatory sweating: Clinical implications and etiologic aspects

Purpose: It was the aim of this study to provide detailed general informati on on the clinical picture of different kinds of gustatory sweating, includ ing reevaluation of a series of patients who underwent parotidectomy, remov al of the submandibular gland, or neck dissection. Patients and Methods: This study summarizes the statements of 548 patients questioned about the occurrence of gustatory sweating after parotidectomy ( n = 296), extirpation of the submandibular gland (n = 79), and neck dissect ion(n = 173). Results: After parotidectomy, 45% of the patients had noticed gustatory swe ating, In most of them (70%), the symptoms began within 6 months after surg ery. Gustatory sweating developed in only one patient with submandibular ex tirpation (1.5%), and not at all after neck dissection. Most patients (52%) reported that the symptoms occurred independent of the kind of food ingest ed. These results show that the "masticatory component" is an important tri gger for Frey's syndrome. Application of Minor's test localized gustatory s n eating mainly in the region of previous parotid lobe removal, but also in other areas deriving their sensory supply from the auriculotemporal, great er auricular, and lesser occipital nerves. The size of the area affected by the sweating was similar after lateral and total parotidectomy. When evalu ating clinical symptoms, subjective assessment by the patients seemed to pl ay a major role. After submandibular extirpation and neck dissection, some patients reported gustatory sweating that was not verified by Minor's test. Conclusion: There is general agreement that the cause of gustatory sweating is sympathetic or parasympathetic innervation of previously denervated swe at glands, initiated by gustatory triggers. The location of the "erroneous innervation" depends on the type of lesion. In cases after parotidectomy mi sdirected parasympathetic regeneration is the model integrating all known f actors into a rational concept. For didactic and systematic-pragmatic reaso ns, a clinically oriented classification of gustatory sweating (types I to III) seems to be useful.