Progression of preexisting trigeminalgia to Tolose-Hunt-like syndrome. The importance of neuroimaging for early differential diagnosis.

Recurrent unbearable, paroxysmal, unilateral facial pain in the distribution of one or more branches of the trigeminal nerve often provoked by sensory stimuli is typical for idiopathic trigeminal neuralgia. The less frequent localization in the area of ophthalmic branch (5%) is particularly controversial and should be distinguished from pathological lesions in the brainstem and middle and posterior cranial fossa and from diseases of the orbit and eye. This case study presents a 79-year-old woman with typical clinical features of 1st division trigeminalgia without any neurological loss and with normal results of laryngological, ophthalmological, and stomatological examinations as well as neuroimaging CT, and MR /MRA evaluation. Only the evoked potential blink and masseter reflexes demonstrated the pathological values in the early phase of illness. After 1 year of pharmacological treatment no improvement was achieved and the pain became neuropathic and paresis of 3rd, 4th and 6th nerves developed, as observed in Tolose-Hunt syndrome. MRI of the orbit revealed a pathological mass in its apex with a connection to the superior orbital fissure. However, treatment with steroids was completely ineffective. Surgical resection of the tumor (leiomyosarcoma) only partially reversed oculomotor palsy and diminished aching. In differential diagnosis of idiopathic and symptomatic trigeminalgia, early MR and MRA imaging is the most essential and sometimes may be the best single test to evaluate lesions even in distant areas of the nervous system branches.