Defining the “edge of the envelope”: patient selection in treating complex sellar-based neoplasms via transsphenoidal versus open craniotomy

Abstract

Since the reemergence of the transsphenoidal approach as a primary means of accessing and resecting sellar region tumors in the 1960s by Hardy and Guiot, several key advances have improved the ability to safely treat patients with larger and increasingly complex tumors of the anterior and middle skull base. 28,43 In particular, the operating microscope, extended transsphenoidal approaches, advanced neuroimaging, intraoperative neuronavigation, and neuroendoscopy have collectively improved the ability to safely treat many of these lesions. The evolution of extended transsphenoidal approaches and endoscopic instrumentation has facilitated surgical access to lesions of the midline skull base via natural corridors, along a wide arc from the frontal sinus to the odontoid process. 9,31,34,53 Equally important are recent developments in effectively reconstructing the skull base after tumor resection, thereby reducing the incidence of CSF leakage and associated infection, which has traditionally been one of the major pitfalls associated with transsphenoidal and related skull base approaches.As the subspecialty of endoscopic skull base surgery continues to "push the edge of the envelope" in regard to the spectrum of lesions that can be effectively and safely treated, the key limitations to the types and extent of tumor pathology that can be optimally resected via these approaches must be continuously reassessed. In some instances, these limitations are inherent to an individual tumor's biology and pose a surgical challenge regardless of the operative approach that is undertaken. Nevertheless, patient selection remains of paramount importance Results. Thirteen cases exemplifying some of the existing limitations to achieving optimal surgical outcomes via transsphenoidal-based approaches are presented. The following 8 factors are separately discussed that repeatedly limited the extent of resection, increased the risk of the operation, and contributed to perioperative complications: significant suprasellar extension, lateral extension, retrosellar extension, brain invasion with edema, firm tumor consistency, involvement or vasospasm of the arteries of the circle of Willis, and encasement of the optic apparatus or invasion of the optic foramina.Conclusions. Although the ability to approach and resect complex tumors using endonasal skull base techniques has evolved dramatically in recent years, several inherent tumor characteristics mandate extensive preoperative consideration. In selected cases these characteristics may lend support to selecting an open craniotomy as the initial operation. (DOI: 10.3171/2010.8.JNS10520) Key words • transsphenoidal approach • endoscopic surgery • skull base surgery • pituitary adenoma • meningioma • craniopharyngioma • invasionAbbreviations used in this paper: ACA = anterior cerebral artery; DI = diabetes insipidus; EBRT = external-beam radiation therapy; FSH = follicle-stimulating hormone; GTR = gross-total resection; ICA = internal carotid artery; PBRT = proton-beam radiation therapy; P...

Endoscopic endonasal resection of skull base meningiomas: the significance of a “cortical cuff” and brain edema compared with careful case selection and surgical experience in predicting morbidity and extent of resection

“…Moreover, several recent papers have tried to outline factors that correlate with higher morbidity to assist the clinician with patient selection. In this paper we examined 2 of these factors, namely the absence of a cortical cuff indicating the proximity of small perforators to the tumor capsule, 26,52 and the presence of brain edema as an indication of brain invasion. 52 Our results in this large series of meningiomas indicate that these factors may not be as important as careful case selection and technical skills that are acquired over time.…”

“…26,52 Fifth, any evidence of edema in the adjacent brain indicates possible brain invasion requiring complex brain dissection and hemostasis techniques not possible with endonasal surgery. 52 While each of these points has merit, they are primarily derived from results achieved in the early years of endonasal surgery before the development of a variety of technical advances that have made these approaches both more effective and safer. Likewise, recommendations regarding appropriate case selection were not clear given the lack of experience and consensus within the endonasal surgical community.…”

Size does not matter. The intrigue of giant adenomas: a true surgical challenge

“…The same principles are valid in cases of giant adenomas, where the extended approach has proved to facilitate, in most instances, a wider lesion exposure just after the dural opening over the sellar-suprasellar space, thus avoiding any retraction of neurovascular structures [16][17][18][19]. However, there are conditions that could render more troublesome the transsphenoidal approach, either related to the anatomy of the surgical route or to the inner features of the lesion itself, i.e., the size of the sella, its degree of ossification, the size and the pneumatization of the sphenoid sinus, and/or carotid arteries position and shape [1,6,20,21].On the other hand, transcranial surgery should be preferred when tumors present with extensive intracranial invasion, with asymmetric lateral development, into the anterior cranial fossa or lateral or posterior extension into the middle and posterior cranial fossa, particularly if major vessel involvement is present and/or whether transsphenoidal surgery has been already unsuccessful, and in these regards, several authors have reported surgical strategy and results, properly addressing indications, pros, and cons [22][23][24].When perceiving this controversial scenario, we moved backward through our series and analyzed the decisionmaking process, i.e., surgical approach choice, in those special-featured adenomas (giant, asymmetric, dumb-bell shaped). Although it is not possible to define a unique paradigm of management, we could thread a common line of attitude we have been relying on.…”

“…The same principles are valid in cases of giant adenomas, where the extended approach has proved to facilitate, in most instances, a wider lesion exposure just after the dural opening over the sellar-suprasellar space, thus avoiding any retraction of neurovascular structures [16][17][18][19]. However, there are conditions that could render more troublesome the transsphenoidal approach, either related to the anatomy of the surgical route or to the inner features of the lesion itself, i.e., the size of the sella, its degree of ossification, the size and the pneumatization of the sphenoid sinus, and/or carotid arteries position and shape [1,6,20,21].…”

In-Hospital Postoperative Complications in Patients With Pituitary Adenoma Who Underwent Pituitary Surgery From January 2010 to December 2015: A Multicenter Study

“…However, there are also comprehensive surgical modifications that permit access and provide effective initial management of giant PAs with favorable results [22]. There are certain features that favor the transcranial open craniotomy over the trans-sphenoidal route, specifically, significant supraor retrosellar or lateral extensions of the tumor, brain invasion with edema, firm tumor consistency, involvement or vasospasm of the arteries of the circle of Willis, and encasement of the optic apparatus or invasion of the optic foramina [23]. In this study, almost half of patients had extensive tumors and one-third had cavernous sinus invasion.…”