ODP324 Internal Carotid aneurysm inside a pituitary macroadenoma: case study and literature review

Abstract

Abstract BACKGROUND: Coexisting pituitary adenoma (PA) and intracranial aneurysms (IA) is relatively frequent. However, the finding of an aneurysm inside a PA is extremely rare. We report a patient with pituitary macroadenoma with an embedded internal carotid artery (ICA) aneurysm, who presented with anterior hypopituitarism. CLINICAL CASE: 73 y. o. black female presented after a fall secondary to orthostastic hypotension. In the ER her BP was 78/50 mmHg, HR 76/min sinus rhythm. She reported fatigue, presyncope, and 20 lbs weight loss in the preceding 3 months. CT head without contrast showed a sellar mass. Pituitary MRI confirmed a 20×24×29 mm sellar mass consistent with a macroadenoma extending laterally to both cavernous sinuses with bilateral encasement of ICAs, superiorly elevating optic chiasm, and mild extension to the left Meckel's cave. The study also incidentally showed a > 5 mm ICA aneurysm embedded within the macroadenoma. Diagnostic cerebral angiogram demonstrates a medially directed left superior hypophyseal ICA aneurysm measuring 5.4×4. 0 mm with a 3.5 mm neck. The patient denied headaches, peripheral vision loss, or polyuria. On examination her weight was 154 lbs, height 5'6", normal visual field testing, and no neurologic deficits. Endocrine testing was consistent with anterior hypopituitarism: ACTH 17 pg/mL (10-48), Cortisol 4.7 mcg/dL (6-18.4), TSH 1.4 mIU/L (0.4- 4. 0), FT4 0.7 (0.7-1.9 ng/dL), IGF1 7 ng/mL (55-162), Prolactin 38.3 ng/mL (4.8- 23.3), and FSH 6.6 IU/mL (20-138). Clinical improvement followed hydrocortisone and levothyroxine replacement. Patient was discharged home with a plan for outpatient endocrine follow up and subsequent endovascular intervention. Unfortunately, she presented a few weeks later with pulmonary embolism, for which she was treated with Eliquis. Given high risk of bleeding, the plan for endovascular embolization was postponed. Patient was educated about sick day rules and is set for routine endocrine visit and periodic MRI surveillance of the macroadenoma. DISCUSSION: intracranial aneurysms appear to occur more frequently in association with PAs than among the general patient population. In 2 cohort of patients with PA, 5.4-7.3% had coexisting IAs, the majority of which are outside the pituitary region. However, the presence of an aneurysm embedded within a PA, as in our case, is very rare, and most are discovered by accident. In such cases, although spontaneous aneurysm rupture or pituitary apoplexy is extremely rare, misdiagnosis of the embedded aneurysm can potentially result in catastrophic outcomes if it is not appropriately recognized and addressed prior to pituitary surgery. Cerebral angiography with embolization or coiling of the aneurysm prior to hypophysectomy can decrease the risk of perioperative rupture or bleeding. In our case, given the risk of bleeding while on anticoagulation therapy, the plan for endovascular intervention was postponed. Presentation: No date and time listed