© Springer International Publishing AG 2018 89
W.T. Couldwell (ed.), Skull Base Surgery of the Posterior Fossa,
https://doi.org/10.1007/978-3-319-67038-6_7
Petroclival Meningiomas
Amol Raheja and William T. Couldwell
A. Raheja, MBBS, MCh (*)
Department of Neurosurgery, All India Institute
of Medical Sciences, New Delhi, India
e-mail: [email protected]
W.T. Couldwell, MD, PhD
Department of Neurosurgery, Clinical Neurosciences
Center, University of Utah, Salt Lake City, UT, USA
e-mail: [email protected]
7
Introduction
Petroclival (PC) meningiomas are skull base
lesions with primary dural attachment along the
PC synchondrosis, typically near the upper two
thirds of the clivus [ 1 – 4 ]. The origins of these
lesions are anatomically situated medial to cra-
nial nerves V and VII–XI than posterior petrous
meningiomas, in which the origin of the tumors
is located laterally to these nerve complexes.
Clival meningiomas in the lower third of the cli-
vus are often categorized separately as foramen
magnum meningiomas, and they are accessed
via entirely different surgical approaches than
their PC counterparts and are covered elsewhere
in this text [ 1 – 4 ]. Although Hallopeau first
described PC meningioma in 1874 [ 2 ],
Olivecrona and Tonnis [ 5 ] described the first
attempt at surgical resection in 1927. Surgery for
these tumors was associated with dismal out-
comes and mortality rates exceeding 50% [ 6 , 7 ]
until the microneurosurgical era [ 8 ]. Since the
original classification of PC meningiomas by
Castellano and Ruggiero in 1954 [ 9 ], multiple
classification schemes have been proposed for
these tumors based on anatomical locations,
tumor extensions, and tumor dimensions. PC
meningiomas are notorious for having tumor
extensions along the cavernous sinus (CS) ,
Meckel’s cave, jugular foramen, sella, parasellar
region, and foramen magnum, making aggres-
sive surgical resection without iatrogenic neuro-
logical deficits technically challenging. The
interposition of cranial nerves between the sur-
geon and the tumor and the intimate relation of
the tumor and the brainstem vascular supply
limit the safe and aggressive resectability.
The management of PC meningiomas has
undergone paradigm shifts over the past few
decades from radical resection to more tailored
surgical decompression that offers deficit-free
survival. These changes have been enabled by
the advent of modern microneurosurgical skull
base techniques, better understanding of the sur-
gical anatomy, and availability of intraoperative
neurophysiological monitoring and efficacious
adjuvant therapy option such as stereotactic
radiosurgery (SRS) in the armamentarium of
modern skull base neurosurgeon. This chapter
reviews the natural history, clinical presentation,
preoperative evaluation, decision-making, surgi-
cal approaches, role of SRS, and treatment
outcomes in the era of multimodality manage-
ment of PC meningiomas.