SAT-LB51 The Unique Etiology and Management of a Third Cranial Nerve Palsy

Background: Cranial nerve palsies (CNP) in association with a hypophyseal process can be uni/bilateral, single, multiple, with or without visual deficits and pain. It is reported 14-30% of pituitary tumors lead to a palsy. Often the acute cause of palsy is apoplexy (1) but other rare etiologies exist such as abscess or prolactinoma (2, 3). Clinical Case: A 40 year old woman with no PMH presented to the ED for acute on chronic headaches. Two days prior she started having blurry vision in her R eye. The headache improved with medications and she was sent home. Two days later she returned with new symptoms of the R eye deviating laterally and down, associated ptosis and a 6 mm nonreactive pupil. A stat MRI brain was obtained for her new CN III palsy, showing a 1.4 cm sellar mass with suprasellar extension. Further history revealed that two months prior her regular menses had stopped. Labs were obtained that included a prolactin 127 (nl 4.8-23.3); fT4 1.2 (nl .93-1.7); IGF1 129 (nl 52-328); 9 am cortisol 16.6 (nl 4-22); FSH 5.5 (nl 3.5-12.5); LH 3.8 (nl 2.4-12.6). Neurosurgery (NSGY) was consulted, recommending a trial of medical therapy since her visual fields were intact. Endocrine then advised cabergoline 0.5 mg twice weekly. In NSGY clinic ten days later, her prolactin was 0.2 but her symptoms remained the same. One month later, she was seen in Neuro-ophthalmology clinic where it was noted that her diplopia had subjectively resolved. Her eye exam was documented as normal except for sluggish pupils. Conclusion: CNP are more common in larger pituitary tumors and often associated with panhypopituitarism and necrosis. About 90% of cases resolve by one year after pituitary surgery. Although our patient had a tumor that was slightly larger than 1 cm, she did not need hormonal replacement, did not have hemorrhage/necrosis, and her symptoms resolved with a dopamine agonist. There is one other case in the literature of medically treated macroprolactinoma with resolution of CN III palsy (3). References: (1) Hage R, et al. Third, Fourth, and Sixth Cranial Nerve Palsies in Pituitary Apoplexy. World Neurosurgery. 2016; 94:447-452.(2) Wang L, et al. Pituitary abscess resulting in isolated abducens palsy. Journal of the Formosan Medical Association. 2016;115:134-135.(3) Harries A, et al. Resolution of third nerve palsy following treatment of prolactinoma with cabergoline. Acta Neurochir. 2010; 152:1741-1743.