Skull Base Approaches for Posterior Circulation Aneurysms

Abstract

With the emergence of skull base surgery, several surgical approaches have been developed and redefined. These approaches provide surgeons with successful avenues to difficult lesions of the cranial base. The majority of lesions in which these skull base techniques have been successfully used have been for tumors. However, we find that with the provision of direct access to basal cisterns from the skull base techniques, complex and giant aneurysms are equally accessible for surgical intervention. In this report, we describe our techniques and results in the use of three different skull base approaches for the surgical management of four different complex posterior circulation aneurysms. The approaches that were used include the cranio-orbital-zygomatic (COZ) approach, the petrosal approach, and the transcondylar approach. Each approach provided a wide field with excellent exposure of vital structures with minimal brain retraction. Clippage of the aneurysm was successfully achieved in all cases. METHODS Cranio-Orbital-Zygomatic ApproachThe procedure for the COZ approach involves modifications based on the supraorbital approach described by Jane et al.1 The basic technical aspects of the COZ approach have been previously described.24 In the COZ approach, a supraorbital-pterional free bone flap is generated that consists of the frontotemporal bone in continuity with the anterior, superior, and lateral rim of the roof of the orbit (Fig. 1). The remainder of the orbital roof is removed as a posterior orbitotomy and reattached to the supraorbital-pterional bone flap (Fig. 2). Oblique osteotomies are placed at either end of the zygoma, and, with the inferior surface of the body of the zygoma attached to the masseter, the zygoma is easily retracted inferiorly, 251

Surgical approaches to jugular foramen schwannomas: An anatomic study

“…Almost all reported approaches added resection of the jugular process. However, previous studies have reported that the transcondylar suprajugular approach with preservation of the wall of the jugular bulb usually results in preservation of its patency after tumor removal even if the preoperative studies revealed an absence of its flow into the jugular bulb …”

“…However, previous studies have reported that the transcondylar suprajugular approach with preservation of the wall of the jugular bulb usually results in preservation of its patency after tumor removal even if the preoperative studies revealed an absence of its flow into the jugular bulb. 6,56,57 Generally, an approach with modifications to widen the surgical field is advantageous. Cervical exposure combined with an infralabyrinthine mastoidectomy and resection of the jugular process can provide a wide surgical field that can be enlarged further through a variety of modifications, including the fallopian bridge technique without translocation of the facial nerve, which provides more surgical space and improves the visualization for the tumor extending to the hypotympanum or anterolateral part of the jugular bulb.…”

Fronto-temporo-orbitozygomatic craniotomy and "half-and-half" approach for basilar apex aneurysms

“…Neither of the approaches, therefore, is sufficient alone as both anterior and lateral orientations are required for successful dissection and clipping of BAA. [16] The alternative skull base approaches to access BAA include Dolenc's modified pterional transcavernous-transsellar approach [17] and, Krisht's pretemporal transzygomatic transcavernous approach. [10] Both these approaches facilitate BAA exposure without significant frontotemporal lobe retraction.…”

“…16 6 4.3 years) presented with SAH due to BAA. Their clinical presentation included sudden severe headache with neck stiffness (n 5 5), recurrent vomiting (n 5 3), transient IIIrd nerve paresis (n 5 2), right gaze palsy (n 5 1) and disorientation or altered sensorium (n 5 4).…”

Skull Base Approaches for Vertebro-Basilar Aneurysms

“…This approach has been used for lesions located very high with respect to posterior biclinoidal line [Jennett, 1975;Kasdon, 1979;Ikeda, 1991;Bowles, 1995;Sindou, 2001] because both zygomatic arch and orbital roof translocation together allow the complete observation of the implant base and the possibility of manipulating these aneurysms from different directions (Figures 11 and 12). performed during the endoscope-assisted microsurgical treatment of a basilar tip aneurysm through a right FTOZ approach; it is clear that the endoscope allows a better panoramic vision of the aneurysm (An) with minimal retraction of the internal carotid artery (ICA) and of the short posterior communicating artery (PCoA) from which a critical perforator (Perf), not visible in pure microscopic vision, enters the mesencephalon; the parental basilar artery (BA) with its distal branches, superior cerebellar artery (SCA) and posterior cerebral artery (PCA), are also better controlled by the endoscope; the scope also allows a better control of the distal portion of the clip (arrows).…”