[Neurotrophic ulceration following thermocoagulation of the Gasserian ganglion]. / Ulcération neurotrophique après thermocoagulation du ganglion de Gasser.

INTRODUCTION: Neurotrophic ulceration (NTU) in the trigeminal nerve sensitive area is rare. It may be caused by a lesion anywhere on the trigeminal nerve's trajectory. The diagnosis is usually clinical, but other diagnoses, particularly neoplastic, must be ruled out first. The physiopathology and treatment of NTU remain controversial. We report a severe case of NTU and describe the main features of this poorly documented disease. OBSERVATION: A 67-year-old female patient consulted in the dermatology department for a progressive ulceration of the nose ala and the right upper lip, having developed over the two previous years. She had undergone two thermocoagulations of the right Gasserian ganglion for facial neuralgia 3 years before. The diagnosis of NTU, initially ruled out because of biopsies suggesting verrucous carcinoma, was finally retained because of the clinical presentation and anamnesis. Treatment consisted in surgical excision and primary reconstruction using a forehead flap. The diagnosis was confirmed after histopathological examination of the surgical specimen. A recurrence was noted 2 years postoperatively, then the patient was lost to follow-up. DISCUSSION: The physiopathology of NTUs is badly documented. The cutaneous ulcerations look like facial neoplasms but the clinical findings (unilateral and paranasal location; lesion of the trigeminal nerve; local trauma; psychological instability) suggest neurotrophic ulceration. The histopathological examination, sometimes difficult, reveals non-specific chronic inflammatory ulceration. There is no consensus on treatment. The psychological profile may be a risk factor for recurrences and must be taken into account.