This document discusses the surgical management of sphenoid wing meningiomas. It covers the anatomy, classification, clinical presentation, diagnosis using CT, MRI and angiography, surgical treatment approaches including pterional, alar/middle, and clinoidal craniotomies, reconstruction after resection, potential complications, and results. The goal of surgery is radical resection of the tumor along with the dural implant and any hyperostotic bone to reduce the risk of recurrence.

1. Surgical Management of
Sphenoid Wing Meningiomas
Schmidek Chapter 36
GERARDO GUINTO

2. Outline
• Anatomy
• Classification
• Clinical course
• Diagnosis
• Treatment
• Complication and result

3. Anatomy

4. Classification

5. En-plaque meningiomas
• Spheno-orbital meningiomas or hyperostotic
meningiomas of the sphenoid wing
• Carpet-like dural growth tumor
• It frequently extends posteriorly toward the cavernous
sinus and anteriorly toward the orbital apex, where it
causes proptosis and oculomotor deficits growth tumor

6. Globoid meningiomas
• Deep, inner, or clinoidal
– Most common
– Subtype : tumors without extradural growth and tumors
with extradural growth into the cavernous sinus
• Middle
• Lateral, outer, or pterional

7. Clinical course
• Most common : Protosis which usually is slowly
evolving, unilateral, nonpulsatile, and irreducible
• Protosis Ddx
– Hyperostosis of the orbital walls
– Periorbital tumor invasion
– Intraorbital tumor
– Venous stasis caused by compression of the
ophthalmic veins

8. Clinical course
• Related symptoms : headache, orbital pain, visual
deficit, ptosis, diplopia, ectropion, conjunctivitis,
corneal ulceration, and scleral hemorrhages
• Clinoidal meningioma
– Visual field problems
– When tumor invade cavernous sinus, the most common
symptoms are oculomotor deficit (especially on cranial
nerve VI) and facial hypoesthesia

9. Clinical course
• Middle or alar meningiomas
– Late symptoms
– Headache and signs or symptoms suggesting increased
intracranial pressure, such as nausea, vomiting, and
papilledema
• Not common
– Memory impairment
– Olfactory hallucinations
– Personality changes
– Seizures
– Hemiparesis

10. Diagnosis
• CT
• MRI
• Angiography

11. Computed tomography
• The extent of bone invasion
• The dural component of these tumors is typically found
as an isodense image with contrast enhancement
• The most common locations of hyperostosis of en-
plaque meningiomas
– the lesser wing of the sphenoid bone
– the greater wing of the sphenoid
– the roof of the orbit
– the inferior orbital fissure
– the infratemporal fossa
– the orbital rim.

12. Computed tomography
• Globoid tumors : well-defined isodense lesions that
present an intense and homogeneous contrast
enhancement
• Clinoidal meningiomas : hyperostosis of the anterior
clinoid process (ACP), causing narrowing of the optic
canal and the superior orbital fissure

13. MRI
• Globoid meningiomas show different appearances on
MRI
– When their vascularity is not so marked, they usually
present as a homogeneous isointense lesion in both T1-
and T2-weighted images
– When they are highly vascularized (angioblastic
meningiomas), multiple hypointense images (“empty
signals”) can be seen in the interior of the tumor

14. MRI
• Gadolinium enhancement is usually intense and uniform
• T2-weighted image is particularly useful in demonstrating
perilesional edema
• Functional MRI
• MRA

15. Angiography
• Selective catheterization provides specific information
about the blood supply of the tumorand allows the
possibility of preoperative embolization

16. Treatment
• Indication
– all patients who are in good health and have a tumor size
greater than 2.5 cm
– presence of signs or symptoms
– changes in the adjacent cerebral(edema)
• Objective
– radical excision of the tumor, which means resection of the
lesion, along with the dural implant (1-cm margin) and all
hyperostotic bone

17. Treatment
• Preparation : general anesthesia, antiepileptic drugs, broad-
spectrum antibiotics, neurophysiologic monitoring
• Positioning and Incision
• Preserve : superficial temporal artery, frontotemporal branch
of facial nerve
•

18. Pterional
• Pterional craniotomy
• Hyperostosis is usually seen immediately in the
pterion once the temporal muscle is detached :
craniotomy about 5 cms from lesion
• Resection of hyperostosis : 1 cm from margin
• The meningeal portion of the tumor : 1 cm from margin
• In some cases of predominantly osseous tumors :
craniectomy

19. Pterional

20. Alar or middle
• Frontotemporal craniotomy
• Extradural resection of the lesser wing of the sphenoid
bone
• Bone removal is continued until complete exposure of the
superior orbital fissure and base of the ACP
• Dura open in curvilinear frontotemporal incision
• Splitting of the sylvian fissure is done
• “En bloc” resection is only possible in small tumors
• Debulking is preferred in the majority of these cases
• Leaving deeper portions and dural implant for the end of the
procedure.

21. Clinoidal
• Frontotemporal craniotomy
• Bone resection of the sphenoid ridge from the pterion to
the base of the ACP
• If there is an orbital component of the tumor, the
posterolateral wall of the orbit is also removed
• Anterior clinoidectomy : holding the ACP with a rongeur
and applying a gentle “wiggle and jiggle” movement of
the surgeon’s wrist
• The curvilinear dural incision is done
• Splitting of the sylvian fissure is done

22. Clinoidal
• Initially, the dural implants in the frontal and temporal
regions are coagulated, which reduces vascular
supply of the tumor and facilitates its resection
• Dissection of the tumor
• The optic nerve is next referred intradurally and released
from the tumor
• Extirpation of the dural implant is done

24. En Plaque
• Pterional craniotomy is combined with an OZ osteotomy
when the lesion extends into the inferior orbital fissure,
infratemporal fossa or orbit
• It is easy to observe the totality of the hyperostosis from
a lateral perspective and the drilling begins
• All infiltrated dura are resected, attempting to extend
this resection beyond the area of dural enhancement
seen on imaging studies.

25. En Plaque

26. Reconstruction and closure
• Closure of the dura
– Local tissue : aponeurotic galea, pericranium, or temporal
fascia
– Distant tissue : fascia lata or abdominal fascia
• Reconstruction of the pterional defect
– Autologous materials : split calvarial bone graft or ribs
– Synthetic materials : methylmethacrylate and titanium

27. Reconstruction and closure
• The floor, the orbital rim or both are removed, all
authors agree that reconstruction is required due to
the high risk of orbital ptosis, postoperative diplopia, or
cosmetic defect
• Reconstruction of the orbital walls is controversial : the
superior and lateral walls of the orbit

28. Complication
• Postoperative hematoma, especially epidural, due to the
wide dural detachment done in some cases and the
spaces created by resection of large bone formations
• CSF leakage due to wide resection of the dural implant
• Seizure
• Cosmetic
• Infection : when prosthetic materials are used for
reconstruction or when frontal ethmoid or sphenoid
sinuses are inadvertently opened

29. Result
• The short and midterm follow-up results after SWM
resection are excellent
• In the majority of cases,gross total resection is
accomplished with minimal morbidity
• However, the critical point is in long-term follow-up
because of the high risk of recurrence, which is inversely
proportional to the degree of tumor resection
• Factors : incomplete resection of these tumors are
extent of bone invasion, underevaluation of the dural
component, and invasion of adjacent neurovascular
structures, anaplasia