Surgical strategy for giant pituitary adenoma based on evaluation of fine feeding system and angioarchitecture

Surgical strategy for giant pituitary adenoma based on evaluation of fine feeding system and angioarchitecture Interdisciplinary Neurosurgery Advanced Techniques and Case Management 8 (2017) 1–3 Conte[.]

Case report

feeding system and angioarchitecture

Yoshikazu Ogawa, M.D., Ph.D.a,⁎ , Kenichi Sato, M.D., Ph.D.b, Teiji Tominaga, M.D., Ph.D.c

a

Department of Neurosurgery, Kohnan Hospital, 4-20-1 Nagamachiminami, Taihaku-ku, Sendai, Miyagi 982-8523, Japan

b Department of Neuroendovascular Treatment, Kohnan Hospital, 4-20-1 Nagamachiminami, Taihaku-ku, Sendai, Miyagi 982-8523, Japan

c

Department of Neurosurgery, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8574, Japan

a b s t r a c t

a r t i c l e i n f o

Article history:

Received 9 December 2016

Accepted 1 January 2017

Available online xxxx

Background: Giant pituitary adenomas continue to carry higher surgical risks, and postoperative acute cata-strophic hemodynamic changes are associated with very poor outcome but remain difficult to predict Method: Surgical planning based on information about thefine angioarchitecture was achieved using C-arm cone-beam computed tomography Particular feeding systems and semi-quantitative evaluations for tumor staining were also investigated

Conclusion: Major blood supply was different from the normal supply to the anterior pituitary gland and did not necessarily correspond to tumor shape and extension Surgical strategy should be established based on the tumor feeding systems and hemodynamics in giant pituitary adenomas

© 2017 The Authors Published by Elsevier B.V This is an open access article under the CC BY-NC-ND license

(http://creativecommons.org/licenses/by-nc-nd/4.0/)

Keywords:

Angioarchitecture

Feeding artery

Giant pituitary adenoma

Surgical strategy

1 Introduction

Modern imaging studies can identify adverse surgical factors

such as cavernous sinus invasion, encasement of major intracranial

vessels, and extensive destruction of the skull base, which are all

known to occur with giant pituitary adenomas However,

postoper-ative acute catastrophic changes without major vessel disturbance

are associated with very poor outcome but remain difficult to

pre-dict Retrospective analysis of a single center experience found

acute hemodynamic changes after surgery in 13 of 177 cases of

giant pituitary adenoma, resulting in 12 deaths[1] The probable

mechanisms of these changes include intratumoral primary

hemor-rhage, acute ischemia and resultant necrosis in the secondary

hem-orrhagic tissues, and increased intratumoral pressure resulting in

continuous hemorrhage[2,3] These mechanisms are associated

with injuries to the minute intratumoral feeders and/or drainers,

which frequently have diameters ofb300 μm, and the resultant

drastic changes in the hemodynamics We describe a case of

surgi-cal planning based on information about thefine angioarchitecture

and feeding systems, and semi-quantitative evaluations for tumor

staining using angiography specially modified for giant pituitary

adenomas

2 Case report

A 65-year-old man was referred to our hospital MR imaging disclosed a huge skull base tumor, consisting of two major compart-ments with a narrow connecting portion at the planum sphenoidale The anterior part of the tumor extended into the interhemispheric fis-sure and the left frontal lobe was significantly compressed upwards The postero-inferior part of the tumor had occupied the enlarged sella turcica with destruction from the sellarfloor to the upper part of the clivus, and protruded to the sphenoidal sinus (Fig 1a, b) After the intro-duction of general anesthesia, the angioarchitecture of the tumors was evaluated with digital subtraction angiography (DSA) using a C-arm cone-beam CT scanner with aflat-panel detector (GE Healthcare, Buc, France) and 50%-diluted contrast medium The three-dimensional vol-ume rendered images and CT-like reconstructions in the sagittal, coro-nal, and axial planes were developed with an Advantage Workstation 4.6 (GE Healthcare) Cone-beam CT angiography identified two inde-pendent feeding systems, from the branches of the left anterior cerebral artery to the anterior part, and arteriovenous shunt-like fastflow from the left meningohypophyseal trunk to the posterior part of the tumor (Fig 1c, d)

2.1 Tumor stain measurement Angiographical image sequence data were processed with Image J (NIH, Bethesda, MD) to measure optical density as the contrast medium passed through the tumor Because tumor staining is regarded as

⁎ Corresponding author.

E-mail address: yogawa@kohnan-sendai.or.jp (Y Ogawa).

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Interdisciplinary Neurosurgery: Advanced Techniques and

Case Management

j o u r n a l h o m e p a g e :w w w i n a t - j o u r n a l c o m

http://dx.doi.org/10.1016/j.inat.2017.01.002

contrast retention in the late phase of angiography, so we measured

dif-ferences in the optical density between the beginning of a run and a

pla-teau of the late phase in the time-density curve[4]

2.2 Tumor removal

Multi-stepped removals were thought to be possible, consisting of

initial surgery using the interhemispheric approach to the anterior

part, followed by removal using the extended transsphenoidal approach

of the infero-posterior part of the tumor Basic strategy was planned as

initial removal and coagulation of the tumor from the side of the main

feeding systems with greater optical density difference, and extending

gradually to the other side The tumor was subtotally (99.4%) removed

except for small remnants in the right cavernous portion (Fig 2) He

was discharged without neurological or endocrinological deficits

3 Discussion

Giant pituitary adenomas are extremely difficult to remove totally,

with the risk of postoperative pituitary apoplexy from the residual

tumors[1–3] The hemodynamics and feeding system of pituitary

adenomas are little understood, partly because these feeding arteries

generally have diameters ofb300 μm and are arranged in mesh-like pat-terns as shown in our case, so are extremely difficult to identify intraop-eratively even with careful exploration DSA cannot easily visualize such fine angioarchitecture Moreover, the present trend to reduction of in-vasiveness of medical procedures may restrain preoperative examina-tion, so only verification of major vessels with MR angiography or CT angiography is performed

The main feeding artery to the anterior lobe is the superior hypophy-seal artery based on accurate anatomical research[5] However, blood supply from the superior hypophyseal artery was barely present in our case originating from the pituitary anterior lobe Our preliminary in-vestigation for giant pituitary adenomas revealed the blood supply was much more extensive from the lower plane of the tumor, suggesting that giant pituitary adenomas may acquire different blood supply pat-terns from the normal anatomy during the process of enlargement[4] The surgical approach is usually decided based on the shape, volume, and extension of the tumor, usually the transsphenoidal or transcranial approach But this tumor is basically removed without intraoperative differentiation of the tumor from its feeding arteries, and these arteries passing through the tumor are cut and torn together with the tumor If total removal could not be achieved a cross section of the tumor with untreated feeding arteries inevitably remains just after the operation,

Fig 1 MR imaging disclosed a huge skull base tumor (a, b), and angiography identified two independent feeding systems (c, d).

which may cause postoperative acute changes in the tumor

hemody-namics and consequent serious complications Detailed preoperative

examination of the feeding system and hemodynamics of this tumor is

not a priority at present, but we emphasize the need for case-by-case

operative strategy to prevent devastating outcomes after surgery for

this so-called benign but formidable tumor

4 Conclusion

Surgical planning was described based on information about thefine

angioarchitecture and feeding systems Case-by-case operative strategy

is essential for giant pituitary adenomas

Conflict of interest

The authors report no conflict of interest concerning the materials

and methods used in this study or thefindings in this paper

References

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[2] M.Y Chong, S.M Quak, C.T Chong, Cerebral ischemia in pituitary disorders – more common than previously though: two case reports and literature review, Pituitary

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[3] S.K Kurschel, K.A Leber, M Scarpatetti, P Roll, Rare fatal vascular complication of transsphenoidal surgery, Acta Neurochir 147 (2005) 321–325.

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