Surgical Management of Sphenoid Wing Meningiomas
Mohamed Emara MD, Alaa Farag MD, Walid Badawy MD,
Hosam Maaty MD, Fathy Elnos MD
Department of Neurosurgery, Banha University
ABSTRACT
Background: Sphenoidal meningiomas constitute 18% of intracranial masses.
Sphenoid wing meningiomas still present a difficult surgical challenge especially when they
are large in size and involve neurovascular structures. Objective: The aim of the study is
to shed light on the management of sphenoid wing meningioma, study the outcome of
microsurgical resection and factors affecting its resectability. Patients and Methods: In
this prospective study, thirty cases were included thirteen outer and / or middle sphenoid
wing, thirteen clinoidal and four meningiomas en plaque. In each case diagnosis was made
clinically and confirmed radiologically and histo-pathologically. Results: Between March
2011 and June 2014, thirty patients with meningiomas primarily originating from sphenoid
ridge were operated, 22 (73.3%) patients were females and 8(26.7%) were males. In
seventeen cases total resection was achieved, and subtotal resection in thirteen cases. In
this study mortality was recorded in two case and morbidity in nine cases. Eight cases has
excellent outcome fourteen were good and six were fair and two died. Conclusion: The
surgical treatment of sphenoid wing meningiomas still represents a challenge for
neurosurgeons. Surgery for sphenoid wing meningiomas poses a variety of problems
reflecting the complex anatomy of the sphenoid region.
Key Words: Meningioma, sphenoid wing,surgical treatment
Correspondence to Alaa A Farag. Department of Neurosurgery Banha University, Egypt.
email: Alaa1farag@yahoo.com
Tel. +2/01287518299
INTRODUCTION
Meningiomas are among the
most common primary intracranial
tumors. They are slow growing tumors
originating from the arachnoidal cap
cells and may occur anywhere that
arachnoid cells are found(8).
Meningioma account for 14.319% of primary intracranial neoplasms
with a reported incidence 4.4 per
100000 person-year. Female : male
ratio is 2:1. The true prevelance is
likely even greater, as incidental
meningiomas have been reported in
2.3% of autopsy examinations. Most
commonly diagnosed in middle-aged
and
eldery
patients.
Cranial
meningiomas are roughly 10 fold
more
common
than
spinal
(9)
meningiomas
-1-
Deletion of the neurofibromatosis type 2(NF2) gene, ionizing
radiation and head truma are associated with an increase risk, while the
role of sex hormones in meningioma
development is still uncertain(8)
Sphenoid wing meningioma
account for about 11.9% of
intracranial meningiomas, they are
classified into lateral sphenoid wing
(or pterional) which are usually
similar to convexity meningioma,
middle (or alar) and medial (or
clinoidal). The medial type tends to
encase the internal carotid artery
(ICA) and middle cerebral artery
(MCA)
as
well
as
cranial
(1)(2)(14)
nerves
.
The clinical presentation of
sphenoid wing meningiomas is
manifestation of increased intracranial
tension. Clinical features unique to
this group of meningiomas include:
exophtalmous, transient diplopia due
to occlumotor nerve dysfunction,
periorbital pain or numbness in the
territory of the V1 branch, progressive
visual loss, and seizures(6)(13).
Contrasted - enhansed cranial
CT and MR imaging are the
predominant imaging techniques used
in the diagnosis and management of
meningiomas; however, in selected
cases,
MR
spectroscopy,
MR
angiography and Positron emission
tomography may be useful(7).
The most appropriate surgical
treatment of lateral and middle
sphenoid wing meningioma is total
removal. Complete removal implies
total removal of the tumor, including
the dural attachment and bone that is
involved with the tumor(9)
Clinoidal meningiomas considered a major neurosurgical challenge
due to involvement of important
neuron-vascular structures, cranial
base techniques can be used for
surgical removal of these tumors with
good results(10).
Sterotactic radiosurgery can be
used as an alternative treatment to
surgery. For incomplety resected or
recurrent tumors conventional radiotherapy is beneficial. When the lesion
is considered unresectable or all other
treatments have failed; hormonal
therapy or chemotherapy should be
considered(15).
Future therapies will include
combination of targeted molecular
agents, and this will most likely be
accomplished
through
continued
progress in the understanding of the
genetics and biological changes
associated with meningioma.(15)
The aim of the study is to shed
light on the management of sphenoid
wing meningioma, study the outcome
of microsurgical resection and factors
affecting its resectability.
-2-
PATIENTS AND METHODS
Between March 2011 and June
2014, a prospective study including 30
patients with meningiomas primarily
originating from sphenoid ridge was
done. The meningioma extended along
the anterior and middle cranial fossae.
All patients were admitted to the
Neurosurgery department in Banha
University Hospital and Nasser
Institute hospital.
In this study, the patients were
subjected to thorough neurological
examination. Computerized tomography as well as Magnetic resonance
imaging, with and without contrast
enhancement, were done for all cases
preoperatively.
MRA
or
CT
angiographies were also done when
the relation of tumor to vessels need to
be delinned. All these patients were
submitted to surgery. Postoperative
CT and MRI was done as a routine.
Tumors
were
classified
according to size into small (less than
3cm in maximum dimention), large
(more than 3 and less than 5cm in
maximum dimention) and giant (more
than 5cm in maximum dimention).
its dural attachment. The aim of
surgery was either total or subtotal
excision
depending
on
the
preoperative imaging study. Pterional
and fronto – orbito - zygomatic
approaches were used.
Intra-operatively, the aim was
complete microsurgical removal of the
tumor aiming to cure the patients
unless the tumor was encasing vessels
or nervous tissue. The plan of tumor
removal included infilterated dura and
bone.
A carefully planned craniotomy
was done exposing the tumor and also
any part of the dura invaded by the
meningioma.
The
dura
was
coagulated, to provide early control of
the tumor blood supply. The dura was
incised in circumferential manner.
Removal of the tumor was
started with internal decompression
depending on understanding of the
bony and neurovascular anatomy of
the middle cranial fossa, sellar and
parasellar region.
Parts of the tumor adherent to
middle cerebral artery or internal
carotid artery or infilterating the
cavernous sinus (CS) were not
removed. Infilterated dura and bone
was removed. Hemostasis was done
with the aid of surgicell. Watertight
dural closure was done using
pericranial flap or fascia lata graft.
The wound was closed in anatomical
layers
Operative Management:
Surgery was performed with
general anaesthesia, with the aid of an
operating microscope and microsurgical instrumentation in all cases.
The choice of surgical approach
for these meningiomas depended on
the location of the tumor and extent of
-3-
The grading for meningioma
resection is conventional Simpson
grading.
In the resection of
sphenoidal meningiomas, sometimes it
is difficult for the surgeon to ascertain
that the entire area of dural
involvement or attachment has been
exposed, resected, or coagulated.
Therefore, we choose to define "Gross
total resection" in this series as
Simpson grade I and II and "subtotal"
for other grades.
Cases
with
histological
evidence of malignancy or with
residual lesions were sent for
conventional radiotherapy or gamma
knife.
Follow up of cases was
conducted in the Neurosurgical
outpatient clinic. Evaluation was done
both clinically and radiologically by
the help of CT and MRI with contrast,
to detect any residual of the excised
tumor.
In this study, the outcome was
considered to be:
Excellent: Total tumor removal
with
improvement
of
clinical
condition with no deficit.
Good: Total tumor removal
without improvement of clinical
condition or with
development of
new treatable deficit or In complete
tumor removal done with improveement of the clinical condition.
Fair:
Incomplete
tumor
removal without clinical improvement
or Total removal with development of
new untreatable deficit or deterioration
of previous deficit.
Poor:
Incomplete
tumor
removal with development of a new
untreatable deficit
RESULTS:
Thirty
patients
with
meningiomas primarily originating
from sphenoid ridge were operated.
Twenty two (73.3%) patients were
females and eight (26.7%) were males.
The mean age was (49.1+10.1) year.
The patients were divided into three
groups according to the origin of
tumor into A, B and, C:
Group A: 13 patients harboring inner sphenoidal (clinoidal)
meningioma
Group B:13 patient harboring
outer and/or middle sphenoidal
meningiomas.
Group C: 4 cases of
meningioma en plaque.
Headache was the most
common presenting symptoms among
the studied cases (83.3%), followed by
symptoms of increased intracranial
tension (76.6%). Visual disturbance
was the third common presenting
symptom (63.3%).
The
above
mentioned symptoms were the most
common among each individual group
(Table 1).
-4-
Table (1): Presenting symptoms among studied groups
Group A
INNER
Symptom
NO=13
Group B
Group C
Total
OUTER&
EN-PLAQUE
No=30
MIDDLE
NO=4
No = 13
NO
%
NO
%
NO
%
NO
%
Headache
10
76.9
11
84.6
4
100
25
83.3
Visual disturbance
12
92.3
5
38.5
2
50
19
63.3
Increased intracranial tension
9
69.2
10
76,9
4
100
23
76.6
Seizures
5
38.5
5
38.5
1
25
11
36.6
Proptosis
0
0
0
0
3
75
3
10
Diplopia
3
23.1
1
7.7
0
0
4
10.3
Motor weakness
2
15.4
4
31.2
0
0
6
20
Impaired consciousness
2
15.4
1
7.7
0
0
3
10
hyperosteosis were found in 40% of
cases. Vascular encasement were
found in 10 patient of clinoidal
meningioma (Table 2).
The most common radiological
finding in our study was homogenous
enhancement of the lesion which
occurred in 90%
of cases and
Table (2): Radiological finding among studied groups
Radiological findings
Group A
INNER
No = 13
Homogenous
NO
12
%
92.3
Heterogeneous
Hyperostosis
Edema
Calcification
Vessels
1
2
5
3
10
7.7
15.4
38.5
23.1
76.9
Group B
OUTER&
MIDDLE
No = 13
NO
%
12
93.2
1
6
7
5
1
In 17 patient (56.6%), tumor
were totally resected (Fig. 1 and fig. 2)
and tumor were subtotally resected in
13 patients (43.3%).Subtotal resection
was more predominant in group A,
nine patients (69.3%). Total resection
7.7
46.2
53.8
38.5
7.7
Group C
ENPLAQUE
No = 4
Total
No =30
NO
3
%
75
NO
27
%
90
1
4
2
1
0
25
100
50
25
0
3
12
14
9
11
10
40
46.6
30
36.6
was more predominant in group B,
eleven patients (84.6%).
In this study ten patients
(33.3%) received adjuvant therapy in
the form of conventional radiotherapy
or gamma knife.
-5-
In this study, there was two
with conservative treatment. Two
mortalities, one from vasospasm and
patients had vasospasm. Two patients
the other from fits. Postoperative
had CSF leak and three patients
hemorrhage was occurred in three
developed fits (Table 3).
patients which resolved spontaneously
Table (3): Complications among studied groups
Group A
INNER
NO=13
Complications
Hemorrhage
Group B
OUTER&
MIDDLE
No=13
No
%
1
7.7
No
1
%
7.7
1
0
2
1
2
7.7
0
15.4
7.7
15.4
CSF leak
Wound infection
Infraction
Seizure
Mortality
1
1
0
1
0
7.7
7.7
0
7.7
0
In this study the outcome was
good in 14 patients (47%), excellent in
8 patients (26.7%), fair in 6 patients
Group C
ENPLAQUE
NO=4
Total
No=30
No
1
%
25
No
3
%
10
0
1
0
1
0
0
25
0
25
0
2
2
2
3
2
6.7
6.7
6.7
10
6.7
(20%) and poor in 2 patients (6.7%)
(Table 4).
Table (4): Outcome among studied groups
Group A
INNER
No=13
Outcome
NO
Excellent
Good
Fair
Poor
1
7
3
2
Group B
OUTER &
MIDDLE
No =13
NO
%
%
7.7
54
23
15.4
7
5
1
0
-6-
53.8
38.5
7.7
0
Group C
EN-PLAQUE
No = 4
NO
0
2
2
0
%
0
50
50
0
Total
No=30
NO
8
14
6
2
%
26.7
47
20
6.7
Fig(1): Pre-op and post-op MRI of 60 y male patient with lateral sphenoid wing
meningioma. The tumor was totally excised.
Fig (2): Pre-op and post-op CT and MRI brain of 64y male patient with clinoidal
meningioma. The tumor was totally excised.
histopathologically benign(6). With the
advancements in neuroradiological
studies, one can better appreciate how
difficult these meningiomas are to
cure. Surgical management of these
cases
becomes
increasingly
DISCUSSION
Sphenoid wing is the most
common location for skull base
meningiomas. Meningiomas involving
the sphenoid wing are mostly
-7-
challenging as the site moves inwards
from the pterion to the clinoid(8)
symptoms
were deterioration of
vision in 57 (53.8%), headache in 30
(28.3%), optic nerve atrophy in 18
(17%) seizures in 17 (16.0%),
dizziness
in
15(14.2%)
and
(3)
papilledema in 10 (9.2%) patients .
In the medial or clinoidal
menengioma (Group A patients),
progressive visual deterioration was
found to be the primary presenting
symptom in 92.3% of cases. This
visual deterioration was gradual,
progressive and asymmetrical, always
affecting first the ipsilateral side.
Headache also occurred in 76.9% of
cases of this group. This headache was
gradual progressive and usually
radiated frontally or temporally .Other
symptoms of group A included,
blurring of vision, vomiting, seizures
and
motor
weakness.
Fundus
abnormalities, papilledema was found
in 38.4% of cases and optic atrophy
was found in 53.% of cases .
In the outer and/or middle
sphenoid wing meningioma (group B
patients), headache was found to be
the primary presenting symptom in
86.9% of cases. This is attributed to
the fact that these slowly growing
tumors are still not discovered in the
early appropriate timing and their
diagnosis is delayed until they reach
quite a large size causing the
manifestations. Seizures was found in
38.5% of cases. Other symptoms
suggestive of increased intracranial
tension such as blurring of vision and
vomiting was found in 61.5% of
cases. Gradual progressive diminution
of vision was noted in 38.5% of cases
and was usually affecting the same
side of the tumor. Motor weakness
was present in 31.2% of cases and
altered consciousness in 7.7% of
cases. Papilledema was found in
69.2% of cases while optic atrophy
was found in 15.4% of cases.
In the series of Russel and
Benjamin published in 2008 including
60 patients of sphenoidal meningioma,
25 of them were lateral and middle
sphenoidal meningiomas, the most
common presenting symptoms were
Those results were similar to
those of other series where visual
deterioration was the most frequent
presentation. In the series of Roser
published in 2008 including 256
patients, 174 of them were medial
sphenoid wing meningioma. Visual
disturbance was the most common
presentation account for 66.7% if the
cavernous sinus is infilterated and
60.9% if the cavernous sinus is not
infilterated. The second most common
presentation was headache(16). In the
series published in 2009 by Bassiouni
et al, including 106 patients with
clinoidal meningioma, the mean
-8-
headache and seizures(17) . In the series
of Roser published in 2008 including
256 patients, 19 of them were middle
sphenoid wing meningioma seizures
and dizziness were the most common
presentation. Thirty of them were
lateral sphenoid wing meningioma;
headache and psychological deficit
were the most common presentation(16).
bone of the sphenoid ridge and a
creeping dural tail, the latter of which
is highly suggestive and specific(7). In
our study we couldn’t find a direct
correlation between the dense
enhancement and the vascularity of
the meningioma. Some of the densely
enhancing masses were not found as
hypervascular as expected. This
support the fact that enhancement
depend mainly on lack of blood brain
barrier.
In the meningioma en plaque
cases (Group C patients), proptosis on
the same side of the tumor was found
in 3 out of the 4 patients (75%),
headache occurred also in all cases
(100%), gradual progressive ipsilateral
diminution of visual acuity occurred in
two cases (50%), symptoms of
increased intracranial tension with
blurring of vision in all cases (100%),
and fits occurred in 2 cases (25%) .
These results go hand in hand
with the natural history of these
tumors as described by Cushing and
Eisenhardt in 1938,Jesus and Toledo
series published in 2001 and Roser
series published in 2008.(16)(5)
Pterional approach was the most
common approach used in this study,
used in 26 pateints representing 86,7%.
This was due to that this approach
offers several advantages. It permited a
direct approach to the dural attachment
of the tumor along the sphenoid ridge
and thereby allows for early
devascularization. Wide opening of the
sylvian fissure improves surgical
access and optimizes visualization of
all critical neurovascular structures (the
MCA, ACA, ICA, and anterior optic
pathways). Intradural or extradural
removal of hyperostotic bone of the
sphenoid wing including the anterior
clinoid process could be performed.
Good relaxation of the brain was
achieved by opening the basal cisterns
and releasing the CSF. This maneuver
avoided application of self-retaining
spatulas in many cases(9). This was also
the opinion of Pamir et al in the series
published in 2008 and Bassiouni et al
in 2009.(12),(3)
Preoperative and postoperative
CT and MRI Brain was done for all
patients. In the preoperative images
dense enhancement was found in 27
patients (90%) and was caused by the
lack of blood brain barrier in these
extra-axial tumors. The margins of the
enhancing
mass
are
sharply
demarcated, with broad base against
-9-
The size of the tumor was
calculated on the maximum diameter
of tumor obtained from CT scans or
MR images. In
Group A (the
clinoidal variety), from the 13 cases
studied, the tumor was small in three,
large in eight and giant in two cases.
Concerning Group B, from the 13
cases harboring an outer or middle or
whole sphenoid masses one was small,
7 were large and the remaining 5
masses were giant. In Group C, the
en plaque variety, 2 cases were large,
one was small and one was giant.
In this study, we found a
significant
negative
correlation
between degree of resection and
tumour location (as degree of
resection decreases in more medial
tumors). Also, there was significant
negative correlation between degree
of resection and vascular encasement,
as more resection can be achived in
less vascular encasement of the
tumors.
In Group A (the clinoidal
variety), 13 cases were operated in the
study. Total resection was achieved in
4 cases (30.7%) and subtotal resection
was done in 9 patients (69.3%). The
prognosis was excellent in 1 case
(7.7%), good in 7 cases (54%), fair in
3 cases (23%) and poor in 2 cases
(15.4%). Two patients died post
operatively one from vasospasm and
the other from post operative fits. Post
operative hemorrhage was recorded in
one patients (7.7%). He was managed
conservatively. Two patients (15.4%)
developed infarction (vasospasm) one
of them died and the other had
hemiplegia. CSF leak occurred in one
patient (7.7%). It stopped with the use
of lumbar drain. One patient had fits.
He needed mechanical ventilation and
died later.
The extent of resection of
clinoidal meningiomas varies in
different series. The rates of total
resection vary between 43 and 91%.
Table (5) shows the different reported
series of clinoidal meningiomas.(9)
- 10 -
Table (4): Different reported series of clinoidal meningiomas(9)
Series
No of
patients
Mortality
-%
Cs
involve
ment
Improve
ment of
vision %
Extent of
resection-%
Mean
follow
up
Recurrence
/progression
-%
Gross total 83
Major
morbi
dity
-%
8
Almefty, 1990
24
8
38
8
57 m
4
Puzzilli et al, 1999
33
15
39.4
Gross total54.5
12
53 m
26
Day,2000
6
0
100
Gross total66.6
0
3m
0
Goel et al,2000
60
5
23
Gross total 70
12
26 m
2
Lee et al,2001
16
0
14
75
Gross total 87
0
37 m
0
Tobias et al,2003
26
0
23
71
Gross total 77
11.5
42 m
0
Nakamura et al,2006
108
0
64
Gross total 43
7.4
6.5 y
23
Russel et al,2008
43
0
2
85
Gross total 91
18.6
39 m
9.3
Pamir et al,2008
35
0
31
63
Gross total 69
18
12.8 y
9
Bassiouni et al,2009
106
1.9
29
40
Gross total 59
17
6.9
In this study, lateral and/or
middle sphenoidal meningioma group,
aggressive
bony
removal
was
performed to the hyperostotic bone.
At the end of the procedures, the
dural attachment was coagulated.
Gross total resection was achieved in
11patients (84.6%), while in 2 patients
(15.4%) subtotal resection was
performed. In the latter two cases,
total removal was not achieved as the
MCA or one of its branches was
encased by the tumor. The outcome
was excellent in 7 patients (53.8%),
good in 5 patients (38.5%), and fair in
1 patient (7.7%). Post operative
hemorrhage was recorded in one
patient (7.7%). It did not need surgical
intervention. Post operative fits
occured in one patient (7.7%) and also
wound infection occurred in one
patients (7.7%). CSF leak occurred in
one patient (7.7%) and stopped with
repeated dressing. Brotchi and Bonnal
in 2006 reported the same results with
nine patients(4). In the series of
Morokkoff et al published in 2008
including 163 cases, there was no
mortality, they had complication rate
of 9.4% and 1.7% developed new
neurological deficit of their cases(11).
In this study, four cases with
meningioma en plaque were operated.
Two of them were totally excised
(50%) and two patients were
subtotally excised. The surgical
outcome was fair in 2 cases and good
in 2 cases. There was no mortality,
- 11 -
one
patient
complicated
with
hemorrhage post operatively resolved
with serial follow up, and another one
patient
complicated
with
fits.
Superficial wound infection occurred
in one patient. It resolved with
repeated dressing. Proptosis improved
partially in all patients. In the series of
Roser published in 2008, including 86
patients, gross total resection was
achived in 38% of cases with
recurrence rate 32%. In his series 5
patients (7.1%) had hygroma, 5
patients had hydrocephalus, infarction
occurred in 2 patients and hemorrhage
occurred in 2 patients. One patient
died from pulmonary embolism(16)
The objective in every procedure,
should be total removal of the
meningioma.
In the clinoidal variety,
clinoidal masses not attached to the
carotid artery branches, total resection
is recommended. For clinoidal masses
attached to the carotid or cavernous
sinus
subtotal
resection
is
recommended.
For en plaque variety, an
extensive resection of tumor, dura and
bone will lead to good tumor control
with minimal morbidity, good
cosmetic and functional results.
Radiotherapy and radiosurgery
play an increasing role in controlling
residual or progressive disease
CONCLUSION:
The surgical decision for these
tumors should depends primarily on
the clinical finding of the patient and
radiological finding of the tumor.
Location of the meningioma is an
important factor determining the
degree of tumor resectability.
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- 12 -
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