"Neurotrophic Keratopathy Associated With Mandibular Cancer: A Case Report"

To report a rare case of stage III neurotrophic keratopathy (NK) in a fifty- year-old male patient, associated with direct damage of the trigeminal nerve that was caused by a squamous cell carcinoma of the facial skull; also, to elaborate on the management of the resulting extended full-thickness penetrating corneal ulcer.

The patient attended the emergency department of our hospital due to an extended corneal ulcer with central full-thickness perforation, iris prolapse and athalamia in his left eye. Corneal sensitivity was extremely reduced. The patient presented no symptoms, except for a sudden decrease in visual acuity.His recent medical history included a primary squamous cell, infiltrating the middle and lower third of the face and expanding to the nasopharynx and the base of the skull.

The patient had undergone several cycles of chemotherapy and radiotherapy, since the primary tumor had been considered inoperable upon diagnosis. Nerve damage, associated with the intracranial expansion of his primary malignancy resulted in stage III NK. This is, to our knowledge, the first report of a primary malignant lesion of the facial skull, causing neurotrophic ulcer and cornea perforation. 

The ulcer was treated with cyanoacrylic glue at the site of the corneal defect, followed by a modified suturing technique: this consisted in creating a grid with sutures and applying the glue on the suturing net to enhance stability and attachment of the glue on the cornea. A therapeutic lens was also applied, along with daily topical antibiotic drops (ofloxacin). On the first postoperative day the anterior chamber was notably deeper and it remained deep one month postoperatively.

Neurotrophic keratopathy associated with direct damage of the trigeminal nerve is a challenging condition in terms of  both diagnosis and treatment. Early diagnosis can prevent severe complications and management depends on the stage of NK and the underlying clinical manifestations. Each case may present with unique clinical features, warranting alternative treatment methods.