Ординатура / Офтальмология / Английские материалы / Primary Optic Nerve Sheath Meningioma_Jeremic, Pitz_2008

Clinical Evaluation of Primary Optic Nerve Sheath Meningioma

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table 3.4. Clinical characteristics at presentation in 64 patients with ONSM

Descriptor

Present

Absent

Unknown

Right eye

30 (51.7%)

(excluding bilateral disease )

Left eye

28 (48.3%)

(excluding bilateral disease )

Both eyes

6 (9.4%)

Proptosis

23 (37.7%)

38

3

Nerve head edema

22 (43.1 %)

29

13

APD

56 (93.3%)

4

4

Motility abnormality

19 (30.2%)

44

1

Shunt vessels

4*

(Likely underreported)

From Table 3, Turbin RE, Thompson CR, Kennerdell JS, Cockerham KP, Kupersmith MJ (2002) A long-

term visual outcome comparison in patients with optic nerve sheath meningioma managed with observa-

tion, surgery, radiotherapy, or surgery and radiotherapy. Ophthalmology 109(5):890–899

table 3.5. Initial and final visual data in 64 patients with primary ONSM

PROOFS

1.0 to 0.5

0.4 to 0.05

D

Less than 0.05

E

Initial visual acuity (ratio)

36 (56.3%)

8

t

20 (31.3%)

(12.5%)

C

Final visual acuity (ratio)

18 (28.1%)

10

E

36 (56.3%)

(15.6%)

0

R

1

>0.3

<0.3

Unknown

Initial color vision*

29 (51.8%)

R10 (17.9%)

20 (35.7%)

36 (64.3%)

8

Final color vision*

CO

6

(11.1%)

10 (18.5%)

44 (81.5%)

10

42 (77.8%)

N

0

1

2

3

4

Unknown

Initial field grade†

u6 (9.7%)

20

(32.3%)

10 (16.1%)

20 (32.3%)

6 (9.7%)

2

Final field grade†

5 (8.1 %)

8

(12.9%)

10 (16.1%)

13 (21.0%)

26 (41.9%)

2

24

R. E. Turbin and J. S. Kennerdell

3.3.3

3.3.3.1

Growth Patterns

Growth Patterns Defined

In general terms, primary ONSM progression is asso-

The classification of general growth patterns has been

ciated with chronic optic nerve compression and occa-

detailed over the years by various authors, but Rootman’s

sionally invasion of the nerve as in other forms of men-

classification of four patterns (tubular, globular, fusi-

ingioma that involve cranial nerves (Larson et al. 1995;

form, or focal) is a clinically relevant summary of tumor

Sen and Hague 1997). This causes typically painless,

configuration (Figs. 3.5–3.9). He further subdivided the

progressive loss of visual function, and signs of optic

tubular pattern into tubular-diffuse, tubular with apical,

neuropathy including ipsilateral relative afferent pupil-

and tubular with anterior expansion (Table 3.6). The

lary defect, optic atrophy and nerve fiber layer loss that

combined experience (88 patients) of the University of

may be preceded by optic nerve head swelling. Patients

British Columbia series and the University of Amster-

may experience other symptoms and signs detailed

dam between 1976 and 1999 (Saeed et al. 2003) was

above (Tables 3.2–3.5), and the pattern of involvement

described in both Rootman’s textbook and a recent ret-

is typically reflected by extent, severity and duration of

rospective study (Rootman 2003; Saeed et al. 2003).

disease, as in other forms of compressive optic neuropa-

However, with the exception of the tubular pattern

thies. It is therefore germane to introduce some detail

with apical expansion which demonstrated the worst

concerning growth patterns and pathophysiology which

visual prognosis, no correlation was found between

will be discussed in subsequent chapters.

3.38 mmPROOFSand in length by 0.12 mm per year, and non-

ONSM configuration and visual outcome in his series.

The authors do cite the trend towards early visual loss,

and a higher tendency toward intracranial extension in

patients with intracanalicular ONSM. Of all patients,

27% suffered no light perception vision (NLP) before

intervention. Calcified lesions increased in volume by

D

3

calcified lesions grew six times faster, increasing in vol-

C

Eume by 23.45 mm3 and in length by 0.6 mm per year

t(Rootman 2003; Saeed et al. 2003).

E

R

Clinical Evaluation of Primary Optic Nerve Sheath Meningioma

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PROOFS

Fig. 3.8. Focal meningioma affecting the right intracranial

D

optic nerve segment, shown with T1 fat suppressed axial MRI.

E

t

Courtesy of Roger Turbin, MD

C

E

Configuration

number

optic Cancal

Intracranial

tram tracking

Clacification

Irregular

Involvement

Involvement

Margins

Dense

scatter

Tubular

Diffuse

33

20

11

11

11

3

3

Apical expansion

11

8

7

4

3

0

1

Anterior

2

0

0

0

0

0

0

expansion

Globular

17

6

2

3

3

1

9

Fusiform

8

3

1

1

1

0

2

Focal enlarge-

3

0

0

0

0

1

0

ment of optic

nerve

Total

74

37

21

19

18

5

15

From Saeed P, Rootman J, Nugent RA et al. (2003) Optic nerve sheath meningiomas. Ophthalmology 110(10):2019–2030

3.3.3.2

PROOFS

earlier visual loss and optic atrophy has been described

Variations in Growth Pattern

D

Ewith intracanalicular ONSM, a location which provides

and Location Affect Symptoms

tlittle room for growth before atrophy sets in (Ortiz

C

et al. 1996; Castel et al. 2000; Jackson 2003). How-

Variation in growth pattern may cause vision toEbe af-

ever, cases of posterior involvement with swelling of

fected at different rates and different stage Rof disease.

the optic nerve do occur (Lindblom 1992b). Although

Numerous authors have quoted Clark’s descriptionR

that

intracanalicular and posterior orbital lesions may rarely

anterior nerve sheath meningioma located behind the

be associated with disc swelling (Kennerdell and Ma-

globe may spread extradurally or in a more relaxed

roon 1975), almost all cases with disc swelling affect

CO

the more anterior orbit (Lindblom 1992b),

fashion in the area where the nerve sheath inserts onto

N

the posterior globe, limiting compression of the nerve

u

and preserving vision until late in the course. With in-

creased growth, these patients may present with prop-

tosis prior to visual loss (Figs. 3.10 and 3.11). Some

tumors, before they spread to reach the distal optic

nerve, cause a cystic expansion of the distal perioptic

optic space (Lindblom et al. 1992a, b; McNabb and

Wright 1989; Frasier and Green 2002) or a cystic

expansion of the meningioma itself (Figs. 3.12 and 3.13)

(Laitt et al. 1996; Bosch et al. 2006).

Posterior tumors may be more confined to the dura

and expand within the sheath, causing chronic com-

pression or actual optic nerve invasion, which contrib-

utes to choking off of the blood supply and limitation of

axoplasmic flow. These changes lead to loss of vision and

optic atrophy, often with only limited proptosis. This

Fig. 3.10. Clinical photograph of 8 mm of left proptosis in a

may occur with or without preceding optic disc swell-

patient with a left anterior, intraorbital ONSM and 20/20 vision

ing (Clark et al. 1989). A similar presentation with

OU. Courtesy of Roger Turbin, MD

Clinical Evaluation of Primary Optic Nerve Sheath Meningioma

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Clinical Evaluation of Primary Optic Nerve Sheath Meningioma

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nal opening. Rootman describes half of the patients in

more aggressive, Dutton concluded that there was little

his series with bilateral ONSM to have radiographic in-

evidence to support that contralateral visual morbidity

volvement of the planum sphenoidale in continuity with

or patient mortality was at higher risk in these pediat-

both optic canals (Saeed et al. 2003; Rootman 2003).

ric ONSM. Although five deaths were reported in cases

The spread of an initially unilateral primary ONSM

of pediatric ONSM, all were related to operative com-

across to the contralateral optic nerve is rare.

plications or other causes (Alper 1981). In children it

may be difficult to differentiate the more common op-

3.4.4

tic nerve glioma from optic nerve sheath meningioma,

and there are no completely valid clinical criteria (Karp

Optic Nerve Sheath Meningioma in Pregnancy

et al. 1974). The entire clinical and radiographic picture

Growth of ONSM may be initiated or accelerated in

must be considered, with occasional resort to incisional

or excisional biopsy. Irregular nodular surface, calcifi-

pregnancy. In some cases, a rapid growth phase is ob-

cation, and bone change (hyperostosis) are more com-

served during pregnancy probably mediated by estro-

mon in ONSM, but imaging overlap occurs. Glioma

gen, progesterone, or androgen receptors. As in other

may also be associated with arachnoid hyperplasia that

forms of meningioma, stable, known, or occult ONSMs

may simulate ONSM (Fig. 3.14). Although the numbers

may exhibit accelerated growth and cause visual decline

are exceedingly small, the mean age of onset for five pa-

during pregnancy (Newell and Beamon 1958; Wan

tients with bilateral ONSM was 12.8 years, suggesting a

et al. 1990; Maxwell et al. 1993; Turbin et al. 2002;

predominance in children (Dutton 1992).

Wright 1977).

3.4.6

3.4.5

Ectopic Intraorbital Meningioma

Optic Nerve Sheath Meningioma in Children

DuttonPROOFSreviewed the concept of intraorbital menin-

It has been reported that ONSM in children run a more

gioma arising from a site ectopic to the optic nerve

aggressive clinical course, occasionally requiring com-

D

Esheath. He found an incidence of 4% primary ectopic

plete surgical excision or exenteration (Alper 1981;torbital meningioma similar to Rootman’s citation of 1

Wright 1977; Wright et al. 1989; Ito et al. 1988;CJa-

case in 23 (4%) (Table 3.1). Dutton concluded that the

kobiec et al. 1984; Walsh 1970). Although possiblyE

existence of true intraorbital ectopic meningioma is

R

R

a

b

open to debate, but probably represents a real but rare

infiltrate, nonspecific orbital inflammation (NSOI) or

entity. We have not seen a true case at our institution.

other orbital tumors (Fig. 3.15). Orbital 2D B mode ul-

Authors have argued that these lesions might arise

trasound may occasional be helpful to prove that a large

form orbital mesenchymal cells, represent extensions of

orbital mass is distinct from the intraorbital optic nerve

arachnoid tufts from the optic nerve, or simply may rep-

(Fig. 3.16). MRI and CT characteristics of ONSM are

resent misdiagnosis of other lesions (Karp et al. 1974;

presentedPROOFSelsewhere in this text.

Spencer 1972; Shuanshoti 1973; Tan 1989). We have

Continued visual loss despite the resolution of disc

treated patients initially diagnosed with ectopic menin-

D

Eswelling in presumed NAION, progressive visual loss in

gioma, whose lesions were reclassified as other entitiest“unobserved NAION” after disc edema resolution and

by immunohistochemical analysis after recurrence.C

cases mislabeled posterior ischemic optic neuropathy

E

may harbor occult ONSM. However, in most of these

R

cases chronic progressive visual loss is the rule and

R

diagnosis is reached when visual loss progresses and

3.5

CO

patients are re-imaged with appropriate fat-suppressed

Differential Diagnosis

gadolinium enhanced techniques. Sarcoid optic nerve

involvement (neurosarcoid) is especially difficult to

N

distinguish from some cases of ONSM (Figs. 3.17 and

Optic nerve glioma and meningioma are the common-

u

3.18). The difficulty in distinguishing ONSM from

est neoplasms affecting the optic nerve and may have

overlapping features, although clinical differences sepa-

sarcoid and other forms of inflammatory neuritis and

rate the two lesions (Cooling and Wright 1979). For

perineuritis supports treatment with short empiric tri-

instance, some children thought to harbor optic nerve

als of high dose corticosteroids in patients with atypical

glioma may have ONSM, especially in patients with

radiographic findings or unexpected progressive visual

NF1 and concentric arachnoid hyperplasia (Fig. 3.14).

loss and no other systemic or infectious contraindica-

The clinical presentation of ONSM may occasionally be

tions. Indications and procedures for confirmatory bi-

difficult to distinguish from papillitis, perineuritis, sar-

opsy will be discussed in a subsequent chapter.

coid, unilateral papilledema, diabetic papillopathy, non

arteritic ischemic optic neuropathy (NAION), leukemic

Clinical Evaluation of Primary Optic Nerve Sheath Meningioma

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a

b

Fig. 3.15a–c. It may occasionally be difficult to radiographi-

cally distinguish some orbital tumors such as this biopsy

proven schwannoma from primary ONSM (see axial image a).

However, careful examination of coronal images (b) identified

the tumor (c) located medial to and not intrinsic to the optic

nerve (arrow). At excisional biopsy through a superior medial

orbitotomy, the purple lesion was confirmed to be distinct from

the optic nerve and extended to the orbital apex. Courtesy of

c

Roger Turbin, MD

N

u

Fig. 3.16. Axial MRI images (a) without fat suppression fail

to distinguish a large left orbital mass from the intraorbital

PROOFS

optic nerve. However, 2D B scan ultrasound (b) delineates

b

tumor (white oval) from optic nerve shadow (white arrow).

Courtesy of Roger Turbin, MD

D

E

t