Overview of vascular complications of pituitary surgery with special emphasis on unexpected abnormality

Abstract

Arterial bleeding during transsphenoidal surgery for pituitary adenoma is known complication. This usually happens due to rupture of intracavernous carotid or delayed hemorrhage due to the carotico-cavernous fistula and/or pseudoaneurysm. There is also evidence that cavernous carotid aneurysms may occur with pituitary tumors, yet largest series failed to demonstrate any link between aneurysm formation and pituitary tumors. Usually such an aneurysm rupture results in formation of carotico-cavernous fistula. However, pituitary apoplexy and even epistaxis have been reported. In this paper we present a patient with recurrent pituitary adenoma and cavernous carotid artery aneurysm, which caused significant hemorrhage during the surgery. Although retrospective analysis of MRI disclosed that the patient had the aneurysm before the first surgery, it remained silent until the second operation. Therefore neurosurgeons should be very susceptive to any signal changes on preoperative MR images, especially in recurrent cases, where normal anatomical relations are disturbed by fibrotic tissue. Also, we reviewed the vascular complication of pituitary surgery based on the literature.

Treatment of acromegaly by endoscopic transsphenoidal surgery: surgical experience in 214 cases and cure rates according to current consensus criteria

“…[4][5][6] Because patients with acromegaly differ from other pituitary adenoma cases with respect to increased osteoblastic activity and vascular tortuosity, 12,43 a more extended approach was performed for these particular cases. In the nasosphenoidal stage, sella was exposed from one carotid protuberance to the other, and craniocaudally from the planum sphenoidale to the clivus.…”

“…Because tumors infiltrating or invading the cavernous sinus cause important changes in the course of the ICA, it is important to identify the course of this vessel 4,11,43 in the cavernous sinus preoperatively for a successful operation without any complications. The course of the ICA should therefore be identified with T2-weighted and T1-weighted 3D MRI obtained after addition of Gd.…”

Arterial Spin-Labeled Perfusion Imaging Reflects Vascular Density in Nonfunctioning Pituitary Macroadenomas

“…Preoperative evaluation of ASL-PI provides useful information for avoiding or preparing for the vascular complications of transsphenoidal surgery, which can lead to mortality and serious morbidity. 7,8 We found a strong positive correlation between nTBF and %Ves-sel in the 11 patients with nonfunctioning pituitary macroadenomas, suggesting that ASL-PI reflects the vascular density of nonfunctioning pituitary macroadenomas. To date, the source of the blood supply to pituitary tumors has not been fully elucidated.…”

“…2 The assessment of the differences in vascular density in pituitary adenomas may be helpful for predicting subsequent tumor aggressiveness [4][5][6] and vascular complications associated with transsphenoidal surgery. 7,8 Arterial spin-labeled perfusion imaging is a noninvasive MR perfusion technique that measures CBF by using arterial water as a freely diffusing tracer without the requirement of exogenous contrast material. 9 In clinical applications, ASL-PI has been proved reliable and reproducible for the assessment of CBF in various pathologic states, 1 including cerebrovascular diseases, 10,11 neurodegenerative diseases, 12 and brain tumors.…”

Intra-Operative Rupture of Remote Aneurysm during Transphenoidal Resection of Pituitary Macroadenoma

“…We have only been able to identify one other report of intra-operative hemorrhage during transphenoidal surgery due to rupture of an unknown ACOM aneurysm [13]. Other reports of intra-op aneurysm rupture during macroadenoma removal have been described, however the bulk of these are ICA aneurysms directly manipulated during hypophesectomy [14] [15]. In the three previous cases the aneurysms were found in the anterior circulation.…”