Management of Meningiomas
CEREBELLOPONTINE ANGLE MENINGIOMA
Cerebellopontine angle meningioma. This 41-year-old
woman noted increased numbness in the left side of her face
and decreased hearing in her left ear. A radical subtotal
removal was done, with tumor left encasing the fourth nerve
and going into the anterior wall of the internal auditory
canal. (A-D) MRI axial TI images after gadolinium show
the typical appearance of a meningioma, with the flat surface
against the petrous bone and the dural "tails." This tumor is
arising anterior to the left internal auditory meatus. It may
extend into the internal auditory meatus, as seen here.
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To the Introduction
and Contents of Management of Cranial and Spinal Meningiomas
by ROBERT G.
© Congress of Neurological Surgeons
Honored Guest Presentation
Originally Published Clinical
Neurosurgery, Volume 40, Chapter 17, Pages 321-383, 1992
Used with permission of the Congress of Neurological Surgeons.
HTML Editor: Stephen B.
Tatter, M.D., Ph.D.
The information and reference materials contained herein are
intended solely to provide background information. They were written
for an audience of physicians. They are in no way intended to
constitute medical advise. For medical advise a physician must, of
course, be consulted.
(Meningioma Management, File
These meningiomas may arise from any area
of the dura on the postelior surface of the petrous bone. At
operation four general categories of tumor are found, depending on
where they arise and their relationship to the seventh and eighth
- Anterior to the internal auditory
meatus, displacing the seventh and eighth nerves posteriorly and
inferiorly (Fig. 17.30).
- Between the internal auditory meatus
and the jugular foramen, displacing the seventh and eighth nerves
- Superior to the internal auditory
meatus, displacing the seventh and eighth nerves anteriorly in the
large tumors (Fig. 17.31).
- Surrounding the internal auditory
meatus, with the seventh and eighth nerves engulfed in the tumor.
scan usually defines those tumors that arise posterior to the
internal auditory meatus but will not distinguish the first three
categories. The diagnosis of meningioma is indicated by the flat
surface of the tumor against the petrous bone and the durat "tail"
extending from the tumor.
Cerebellopontine angle meningioma. This 40-year-old
woman had progressively decreased hearing in her left ear and
discomfort around her ear and the side of her head. Total
removal of the tumor was done using a combined posterior fossa
and transmeatal approach. There was normal recovery. (A-D)
MRI axial TI images after gadolinium show a large
meningioma arising posterior to the left internal auditory
In the past I often utilized angiography
when a cerebellopontine angle meningioma was suspected. However, for
most of these meningiomas it is now not necessary, because the MRI
usually gives all the information needed and in most patients the
blood supply comes primarily through the dural attachment.
Embolization has not been a consideration.
In patients with mild or minimal
symptoms, an initial period of clinical evaluation and repeat scans
may be indicated to determine whether there are progressive symptoms
and an enlarging tumor. This is especially true in the elderly.
The indications for operation are a
worsening neurological deficit due to brainstem compression or
cranial nerve compression. In a few patients headache or the
continued presence of a stable deficit such as diplopia or hearing
loss may be the indication. In this series two patients were
asymptomatic. One had documented enlargement on follow-up scans and
the other was concerned about the presence of the tumor. Radiation
therapy has been used when there is regrowth after subtotal or
radical subtotal removal and with small tumors which start to
enlarge in older patients who are being observed.
I use the supine position with the
ipsilateral shoulder slightly elevated and the head turned to the
opposite side. The details have been described (47) (see
Chap. 24). This approach has worked well for visualization of
the important anatomical structures, tumor removal, comfort of the
operator, and avoidance of problems with air embolism or
hypotension. Guthrie et al. (26) described a similar approach. Other
surgeons have used the sitting position and achieved good results
(58, 65, 79).
The key considerations in the operation
- Exposure of the tumor as described in
- Interruption of the blood supply along
the dural attachments.
- Internal decompression combined with
careful dissection of the tumor capsule from the brainstem and
There were 57 patients with
cerebellopontine angle meningiomas, 37 women and 20 men, ranging in
age from 38 to 89 years, with 10 over 70 years of age (Table 17.16).
In the 42 patients listed in Table 17.16, Anterior, the tumor arose
anterior to the internal auditory meatus in 27 and anterior-inferior
in 10 and grew diffusely in five. The extent of the tumor removal is
recorded in Table 17.16. In only 14 patients could I be sure of a
total removal but in another 10 a radical subtotal removal was done.
On follow-up, 34 of the 42 patients had a good result, three had a
fair result because of postoperative disability, four had poor
results because of severe preoperative neurological disabilities
that did not significantly improve, and there was one postoperative
death. This occurred
89-year-old man who had been well until he started to develop
worsening ataxia. CT showed a 4-cm tumor with hydrocephalus. A shunt
was placed, with improvement, but several months later symptoms of
brainstem compression worsened. A subtotal removal was done but the
patient died of a cardiopulmonary complication.
Cerebellopontine Angle Meningiomas|
aT, total removal
RST, radical subtotal removal
ST, subtotal removal
bGood, free of major
neurological deficit and able to return to previous activity
Fair, independent but not able to
return to full activity because of new neurological|
or significant preoperative deficit that did not fully recover
None of the patients with radical
subtotal removal has shown recurrence and all have been followed by
scans. Most of the patients with subtotal removal had large tumors
(>3 cm). Three were growing anteriorly into the middle fossa.
After subtotal removal, 15 of 18 had follow-up scans, which showed
no growth in eight, slight growth in five (three of whom have been
given radiation therapy and two of whom are being observed after
showing no further growth on subsequent scans), and moderate growth
in two of the disabled patients, where nothing further has been
Postoperative complications included
permanent increased ataxia in three, one of whom had to have a
cerebellar infarction removed, one patient with wound infection and
meningitis, and one with a cerebrospinal fluid leak requiring
repair. Several patients had temporary increases in ataxia,
incoordination, or swallowing problems which improved. Four patients
had a shunt for hydrocephalus at some time in their course.
Of the 15 patients with meningiomas
arising posterior to the internal auditory meatus, 13 had a total
removal (Table 17.16). One had a radical subtotal and one a subtotal
removal because of involvement of the lower cranial nerves. All had
a good result. There were no postoperative neurological
complications and no recurrences.
Yasargil et al. (79) reported that 27 of
30 patients had a good result and in 27 the tumor was "radically
excised." Sekhar and Jannetta (65) reported total removal in 14 of
22 patients, with no operative mortality and a good outcome in 16.
Samii and Ammirati (58) reported total removal of all 24 tumors
located posterior to the internal auditory meatus, with a good
outcome for 22 patients. Of 32 patients with tumors anterior to the
internal auditory meatus, 29 had the tumors totally removed and 28
had a good outcome.
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