TRIGEMINAL NEURALGIA AS AN UNUSUAL ISOLATED SYMPTOM OF PITUITARY ADENOMA: CASE REPORT AND REVİEW OF THE LİTERATURE

IntroductionPituitary adenomas (PAs), which are benign tumors of the adenohypophysis, account for approximately 10 % of intracranial tumors and 5 % of adenomas, are locally invasive. PAs can be classified as hormone active adenomas and hormone inactive adenomas that can reach huge proportions without any sign or symptom (10).Trigeminal Neuralgia is one of the most frequent cranial neuralgias. The incidence of TN is approximately 4 per 100 000 persons per year (9). TNs are paroxysmal attacks of pain lasting from a second to 2 minutes and affecting one or more divisions of the trigeminal nerve (3, 12). The pain of TN must have at least one of the following characteristics: as intense, sharp, stabbing, activated by trigger factors, without evident neurological deficit and not attributable to another headache cause (3, 12). Episodes of pain start unexpectedly and should last seconds to minutes. The non-painful stimulation of trigger points that located ipsilateral side of pain could initiated pain episodes. After the pain attacks, there is often a refractive period (14). The most common etiology for TN is disturbance of TN at the root entry zone by a vessel, generally the superior cerebellar artery. However, TN may be present in the absence of vascular contact (15).

The cavernous sinus (CS) is a form of large venous space containing the Oculomotor nerve, Trochlear nevre, Oftalmic and Maxillary divisions of Trigeminal Nerve (located in the lateral wall) and also has Carotid artery and Abducent Nerve (located in the central portion) (10).The preoperative diagnosis of cavernous sinus invasion has an important role in the planning of surgical and adjuvant treatment strategies (22). In the event of CS invasion, cranial nerve findings are observed, especially pathologies of the third, fourth and sixth cranial nerves. However, isolated TN complaint due to invasion of CS by a PA is an extremely rare entity with a limited number of reported cases. Here, we reported a case of PA with an isolated complaint of TN.