This document discusses sphenoid wing meningiomas (SWM), a type of meningioma that originates from arachnoid capcells in the sphenoid bone. It covers the classification, causes, locations, presentation, diagnosis, and surgical treatment of SWM. The standard surgical approach is via a pterional craniotomy for resection of the tumor and involved bone. Complete resection is the goal but recurrence is common long-term due to the invasive nature of SWM. Post-operative complications can include edema, CSF leak, seizures, and infection. Overall short and mid-term outcomes are generally good if a gross total resection is achieved.

1. Payoz

2. Introduction
 Meningiomas orginate from arachnoid capcells
 SWM : bonycrest formed bywings (lesserand greater) the sphenoid bone.
 sphenoid ridge(lesser wing : internal 2/3 & greater wing its external1/3)

3. Cont…

4. Classification by cushings and
eisenhert
 En-plaque/spheno-orbital/hyperostotic
 Globoid meningiomas:
(1) deep, inner, orclinoidal
(2) middle oralar
(3) lateral, outer, orpterional

5. Enplaque/spheno-
orbital/hyperostotic
 carpet-like duralgrowth
 reactive hyperostosis
 extends :
 posteriorly :cavernoussinus
 anteriorly :orbital apex

6. Causes of hyperstosis
 vasculardisturbances
 Irritation of bone without actualinvasion
 previous trauma
 bone production by tumorcells
 osteoblastic stimulation of normalbone
 bonegrowth is actually bone invasion by tumorcells.

7. Location of hyperstosis according
to frequency
 lesser wing of the sphenoidbone
 the greater wing of thesphenoid
 The roof of theorbit
 the inferior orbitalfissure
 the infratemporal fossa
 the orbital rim

8. GLOBOID MENINGIOMAS
(1) deep, inner, orclinoidal
(2) middle oralar
(3) lateral, outer, orpterional

10. Pathophysiology
 Head injury
 Radiations
 Harmonal (estrogen & progestrerone)
 Genetic(loss of DNA on 22chromose)
 Androgen receptors(EGF,PDGF)
 Viruses(Inoue-melnick virus)
 Associated(gliomas,abscess & aneurysms)

11. Epidemiology
 Race( Caucasians, Africans, African Americans,and
Asians)
 Sex(Caucasians:75%women & 25% men.Africansshow
an equal genderratio).
 Age(onset is 50 years increasesthereafter)
 Mortality(5years:87% & 10 years :58%)

12. Histologic findings
 According to the World Health Organization (WHO)
in 1993, :
 Benign (grade I) : do not invade thebrain
parenchyma.
 Atypical (grade II) : mitosis & increased
nuclear-cytoplasmicratio.
 Malignant (grade III and IV) : greatermitosis,
necrosis, and invasion of brainparenchyma.

13. Presentation
 Headache
 orbital pain
 visual deficit
 Ptosis
 diplopia
 Ectropion
 Conjunctivitis

14. Presentation
corneal ulceration,
scleral hemorrhages
Oculomotordeficit
Facial hypoesthesia.
Memory impairment
olfactory hallucinations
hemiparesis.

15. Differenetial diagnosis
 Fibrousdysplasia
 Osteoma
 osteoblastic metastasis
 Paget’sdisease,
 hyperostosis frontalisinterna
 erythroid hyperplasia
 sarcoidosis

16. Workup
CT scan and MRI
carotid arteriography

17. Medical treatment
 Indications:
 atypical and malignant meningiomasas an adjunct to
surgery
 partially resected benign meningiomas
 recurrenceof meningiomasaftera surgical resection.

18. Medical treatment
 Drugs:
 Antiestrogen(tamoxifen:nolvadex)
 Antiprogestrone(gastrinone)
 Mifepristone, RU-486 (Mifeprex)
 Antineoplastic(hydo-oxyurea & interferonalpha
2B)
 Anti-PDGF(trapidil)
 Dopamineantagonist(bromocriptine)

19. Surgery
 Indications:
 size of the lesion>2.5cm
 presence of signs orsymptoms
 patient’scondition
 changes in theadjacentcerebral tissue (edema) on
imaging studies
 surgeon’sexperience.

20. Goal of surgery
 radical excision of thetumor
 resection of the lesion + the dural implant(1-cm
margin) + all hyperostoticbone.

21. Preparation
 intravenous generalanesthesia.
 Antiepilepticdrugs
 broad-spectrumantibiotics
 Glucocorticoids
 Neurophysiologic monitoring

22. Positioning
 supine decubitusposition
 the head fixed in a three-pin headholder
 head is slightlyextension
 rotated toward thecontralateral sideof the tumor
 clinoidal tumors (between 30 and40)
 alar and pterional lesions(between 40 and50)

23. Skin incision
 a frontotemporal(pterional) curvilinear
 starting at the rootof the zygomaticarch, just 5 mm in
front of thetragus
 runs verticallyupward
 Once it passes theear, it is curved rostrallyand
superiorly toward the ipsilateral frontalregion.

24. Variation in skin incision
 The midportion of incision can be extended backward,
especially in cases of pterional meningiomas with large
infiltration of thepterion.
 If an orbitozygomatic (OZ) approach is required, it is
necessary toextend the incisionverticallydown to the
level of the earlobe.

26. Dissection of epicranial planes
 superficial temporal artery
 a posterior branch has to be coagulated
 Dissection continues until the temporal fasciais
identified
 Avoid wide separation between the temporalfascia
and the skin to avoid injury to the frontotemporal
branch of the facial nerve

27. Cont..
 retrograde direction
 two epicranial planes arecreated
 skin and temporal fascia (fasciocutaneousflap)
 temporal muscle alone (muscleflap)

28. Craniotomy & tumor resection
 anatomic variety of themeningioma
 Pterional
 Alar
 Clinoidal
 En-plaque

29. Pterional
 If hyperstosis:around the bone infiltration,bone flapof
around 5cm
 If hyperstosis is absent:standardcraniotomy
 Section the tumortoelevate/remove the bone flap

30. Pterional craniotomy

31. Alar
 frontotemporal craniotomy
 extradural resection of the lesserwing of the sphenoid
bone.
 Bone removal iscontinued until completeexposureof
the superior orbitalfissure
 The dura mater is then opened following a curvilinear
frontotemporal incision, reflecting the dural flap
forward

33. clinoidal
 a frontotemporal
 resection of the sphenoidridge
 The superiororbital fissure is alsocompletelyopened
 the posterolateral wall of theorbit is also removed in
case of orbital part oftumor
 Anterior clinoidectomy:high speeddrill+irrigation

34. Cont..
wide splitting the sylvianfissure
 Retractorsare placed on the frontal and temporal
lobes

35. Cont..
 dural implants :coagulated
 distal branches of theMCA to
be identified
 distal to proximaldirection
 initial debulking
 Arterial dissection:proximally
 The opticnerve

38. En-plaque
 it is easier toexpose theentire hyperostosis
 pterional craniotomy is combined with an OZ
osteotomy,particularly when the lesion extends into
the inferiororbital fissure, infratemporal fossa, ororbit

41. Reconstruction & closure
 resect a free duralmargin
 closure of the dura maternecessarily implies
application of agraft
 Local tissue:aponeurotic galea, pericranium,or
temporal fascia
 Distant tissues fascia:lataorabdominal fascia
 Synthetic & biologic materials, butwith a slightly
higher risk of infection.
 Watertight closure ismandatory

42. Cont…
 reconstruction of the pterionaldefect:
 Autologous materials:splitcalvarial bonegraftorribs
 synthetic materials:methylmethacrylate and titanium

43. Complications
 Postoperative EDH:due towidedural detachment
 Csf leak
 Seizures:if grow near epileptogenicareas
 Cosmetic problems:inadequatereconstruction
 Infection:prosthetic material,sinusopened

44. Results
 In general, the short- and midterm follow-upresults
after SWM resection areexcellent
 In the majorityof 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
inverselyproportional to thedegree of tumorresection

45. THANK YOU