Trigeminal neurotrophic ulcer, or trigeminal trophic syndrome, is typically found in the elderly population.
Most patients have a persistent itching, tickling, or crawling sensation as the result of paresthesia in the trigeminal distribution.
Often, these symptoms begin after surgical trigeminal ablation or injection of alcohol into the gasserian ganglion for treatment of trigeminal neuralgia.
The persistent itching sensation causes the patient to chronically manipulate and scratch the site.
Thus, a factitial diagnosis should not be applied here.
The resulting ulceration is very well demarcated, often removing the nasal ala.
There have been rare reports of trigeminal trophic syndrome causing ulcerations on the forehead, nose, or cheek.
Surgical repair is often unsuccessful because the patient is driven to manipulate the site by the persistence of
paresthesias.
The best treatment is use of an occlusive dressing or prosthesis, which prevents further manipulation.
Other treatments, such as transcutaneous electrical stimulation, pimozide, antibiotics, radiation, cervical sympathectomy, antidepressants,
and vitamin B, have been attempted.
The main differential diagnosis is ulcerated basal cell carcinoma, and a biopsy should be performed on all patients to rule out malignancy. Basal cell carcinoma presents as a pearly nodule with a rolled border and telangiectasias, but may present as a chronic, bleeding ulceration.
A history of radiation treatment may predispose to basal cell carcinoma.
Wegener’s granulomatosis often presents with rhinorhea, mucosal ulcerations, and nodules in thenose with nasal obstruction. Cyclophosphamide has been proven effective in treating the disease.
Pyoderma gangrenosum presents as an ulcer with a purple, undermined border and is extremely painful.
Lesions are most common on the lower extremities and trunk and may be associated with inflammatory
bowel disease. Cyclosporine is an effective therapy for pyoderma gangrenosum.
Tomado de JAAD
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The neurotrophic ulcer of the N. trigeminus
HNO . 2004 May;52(5):447-50.

Trigeminal trophic ulceration is a rare clinical entity after an injury to the sensitive root of the trigeminal nerve, mostly due to therapy for trigeminal neuralgia. Other rare causes are Wallenberg's syndrome or a history of removal of acoustic neuroma. After weeks to years, a slowly progressive ulceration develops due to autonomic dysfunction and the patient manipulation because of serious chronic paresthesia. Finally, in many cases, a significant defect of the nasal arch develops. In spite of typical clinical signs and location, diagnosis is made late in most cases. Reviewing the literature, two cases are presented and diagnostic problems and difficulties of the most effective therapeutic approach are discussed.