Parasympathetic innervation to the lacrimal glands originates in the parasympathetic nucleus of the facial nerve. Fibers extend rostrally with the facial nerve and synapse within pterygopalatine ganglion before reaching lacrimal structures via the zygomatic branch of the trigeminal nerve. Damage anywhere along this pathway may result in partial or complete loss of innervation to the lacrimal glands and resultant “neurogenic KCS”. Neurogenic KCS is frequently characterized by an associated dry/crusted ipsilateral nostril (termed “xeromcyteria”) as a result of impaired innervation of the nasal gland. Potential etiologies include inflammatory, traumatic and/or neoplastic processes. Additional symptoms, depending on site the site of the lesion may include reduced corneal and/or facial sensation as a result of impaired trigeminal nerve function and/or Horner’s syndrome.