Richard N. Aizpuru, Nolan Altman, MD

MD2

M. Quencer, Smirniotopoulos,

MD MD

#{149} Robert

#{149} James

Meningioangiomatosis: and Histopathologic Meningioangiomatosis (MA) is a rare, benign, hamartomatous lesion of the leptomeninges; MA has been considered to be a forme fruste of neurofibromatosis. A review of pathology records for patients with MA who were seen between 1970 and 1989 at the authors’ institutions revealed four patients (three male and one female; aged 2.5-21.0 years; mean, 10.8 years) with a history of seizures but without the stigmata or family history of neurofibromato815. Three patients had undergone either computed tomographic (CT) or magnetic resonance (MR) imaging studies. All patients had undergone craniotomies to obtain tissue for pathologic analysis; a peripheral, leptomeningeal lesior was found in all four patients. At C two patients, the lesions were most consistent with calcification. At T2weighted MR imaging in one patient, the lesion demonstrated a hyperintense periphery with associated edema of the white matter. Histopathologic examination demonstrated characteristic features of MA cortical meningovascular fibroblastic proliferation and leptomeningeal calcification. The accurate diagnosis of MA is important since MA is a benign, surgically correctable cause of seizures.

-

#{149} Michael

Norenberg,

Clinical, Correlation’

M

(MA)

is a le-

rare, benign, hamartomatous sion of the leptomeninges that was tially described by Worcester-Drought et a! as a forme fruste of neurofibroma-

and and

mi-

We reviewed

the (CT)

our

institutions

were

that

to find

recorded

all cases

at

of MA

1970 and

1989. Three male patients and one female patient, aged 2.5-21.0 years (mean, 10.8 years) were found. All had a history of seizures, and none had the stigmata or family

history

of neurofibromatosis.

One

patient had undergone both unenhanced and contrast material-enhanced CT. One had undergone both CT and angiography. One had undergone MR imaging at 1.5 T with both axial dual-echo imaging (repetition time [TRI 2,400 macc and echo time [TEl = 21-100 msec [2,400/20100], with one signal averaged) and T2weighted coronal imaging (2,000/80, with one signal averaged); gadolinium-

From

(R.N.A., University

the

Departments

R.M.Q.)

and

of Radiology Neuropathology

(MN.),

of Miami School of Medicine, Northwest 14th St. Miami, FL 33136;

1115

Department

Hospital, Institute

of Radiology,

Miami (NA.); of Pathology,

Received

December

Miami

R-308, the

Children’s

and the Armed Washington,

Forces

DC (J.S.).

10, 1990; revision

At craniotomy,

meningeal tient (one

request-

ed January 17, 1991; revision received February 15; accepted February 25. From the 1990 RSNA scientific assembly. Address reprint requests

terms:

plasms,

CT,

Brain,

calcification

neodiagno-

#{149} Brain neoplasms, neoplasms, MR studies, 13.1214 #{149} Meninges, CT, 139.211 #{149} Meninges, MR studies, 139.1214 #{149} Meninges, neoplasms, 139.366 #{149} Meningioangiomatosis, 139.366

sis,

13.366

Radiology

13.1211

The #{149} Brain

#{149} Brain

1991; 179:819-821

views

expressed

in this

article

are

2

Current

address: of Minnesota

Department School

on

was obtained at pathologic

linear

lepto-

found in each paparieta! lobe, one lobe, and lobe) (Table).

CT, the lesions attenuation, which

consistent

with

(Figs

or granular

demonwas

calcification.

la, Ia) were

The

either

in appearance,

fol-

lowed a gyriform pattern, and were associated with mild to moderate edema of the white matter (Figs ib, 2b). No significant mass effect was demonstrated. Skull radiography in two patients and angiography in one demonstrated normal findings. On T2-weighted MR images in one patient, the lesion demonstrated a hyperintense periphery with associated edema of the white matter. The central portion of the lesion was strikingly hypointense on the T2-weighted image (Fig 2d) and was faintly hypomntense on the proton-density MR image (Fig 2c). Histopathologic examination demonstrated characteristic features of MAleptomeningeal (arachnoid and pia) fibrous proliferation, psammomatous calcification in the leptomeninges, and penetration into the cortical gray matter along the perivascular spaces (Virchow-Robin spaces) by spindle-shaped fibroblasts, with associated psammomatons calcifications (Fig 2e, 2f). DISCUSSION

those

of the authors and do not reflect the official position or policy of the Department of the Army, Department of Defense, or United States Government. c) RSNA, 1991 University Minneapolis.

per-

performed

a peripheral,

lesion was in the right

calcifications

to R.M.Q. Index

tissue diagnosis

in the left temporal parietal two in the right temporal

most

records

between

not

RESULTS

At unenhanced strated high

METHODS

the pathology

accurate

was

were

examination.

we present tomographic

AND

MR imaging

formed. Craniotomies all patients; enough to enable

resonance (MR) imaging examination of this rare lesion. To our knowledge, ours represents the first published article to correlate the clinical, radiologic, and pathologic findings for MA.

I

enhanced

magnetic pathologic

PATIENTS

#{149}

Radiologic,

ENINGIOANGIOMATOSIS

tosis (1). In this article, findings at computed

MD

MA is part of a spectrum of hamartomatous, meningeal-based lesions that are named according to the elements

of Radiology, of Medicine,

Abbreviations: TE

=

echo time,

MA

TR

meningioangiomatosis,

repetition

time.

819

Clinical

and

Radiologic

Patient/Age

Findings

(y)/Sex

for MA

Clinical

History

Lesion

Seizures

l/2’/2/M 2/5/M

Right

Seizures

Location

parietal

Right

CT Findings*

lobe

temporal

Dense

calcification

MR

at NCCT,

attenuation at CECT Dense peripheral calcification NCCT, high attenuation

lobe

high

Findings

Not performed

at

Not

performed

Not

performed

at

CECT 3/21/M

Seizures

Right

4/9/F

Seizures

Left

NCCT

*

unenhanced

=

CT, CECT

contrast

temporal

Not

lobe

temporal

lobe

parietal

material-enhanced

performed

Granular peripheral at NCCT, gyriform ment at CECT

calcification enhance-

Hyperintense periphery with hypointense center

CT.

involved: meningioangiornatosis (MA), angioneurornatosis, and meningio-encephalo-angio-neuromatosis (1-3). Worcester-Drought et a! first described

MA in 1937

in a patient

with

the stig-

mata gested forme

of neurofibromatosis; they sugthat the lesion could represent a fruste of neurofibromatosis (1).

Two

histopathologic

features

that

are

present in MA are cortical meningovascular fibroblastic proliferation and leptomeningeal calcification (2). Although usually seen with neurofibromatosis,

MA was

described

by Kasantikul

and

Brown in 1981 in two patients who did not have neurofibromatosis (3). To our knowledge, there have been 10 more cases of MA reported in the literature since Worcester-Drought et a! described the lesion in 1937 (2-5). These 10 patients included seven male and three female patients (mean age, 26.6 years; range 10-55 years), who presented with headaches, seizures, and dizziness. At craniotomy, leptomeningeal lesions were found in the right parietal

lobe

in

one

poral

lobe

in

three,

lobe one, and

patient, the

the

right

right

patients

did

not

undergo

any

aging studies. At unenhanced patients, findings were normal abnormal

calcifications

onstrated

in five. in

one

patient,

scribed

lesion

with

riphery

and

hypointense

im-

CT in six in one,

were

At T2-weighted

imaging

dem-

MR

Calcifications

inges

and

perivascular

a hyperintense

pe-

center

in

the spaces

was

leptomenare

dem-

onstrated at unenhanced CT as either linear (Fig la) or granular (Fig 2a) in nature. Fibrous proliferation in the leptomeninges accounts for the enhancement pattern of the lesion: Peripheral high attenuation (Fig ib) or enhancement in a gyriform pattern (Fig 2b) occurs secondary to the superficial meningeal abnormality, with proliferation and extension along the Virchow-Rob-

820

#{149} Radiology

arrow] enhanced nounced

right

and

2.

linear

[white

CT image on

the

(a) Axial

temporal

unenhanced

lobe.

The

arrow)).

Note

demonstrates

periphery

CT image

calcifications

area

of the

the

demonstrates

have

associated

of high

a mixed edema

attenuation

a peripheral, appearance

of

the

(arrows);

calcified

(granular

white

matter.

Ic-

[black (b)

the attenuation

Axial

is pro-

lesion.

in spaces. Edema of the white matter response to the lesion is well demonstrated on T2-weighted MR images; leptomeningeal fibrous proliferation and associated psammomatous calcifications account for signal hypointensity

a well-circum-

demonstrated. To our knowledge, only one previous report of the MR findings of MA exists (5). The imaging findings for MA correlate well with the histopathologic features.

1. Patient in the

frontal

in three, the corpus callosum in and the left temporal lobe in one, in an unspecified location in one.

Three

but

tem-

Figure sion

of

the

lesions

on

these

images

in

(Fig

2c, 2d). Although MA is rare, it represents an important entity for a number of rcasons. In our series, MA was found in four patients (three of whom were children) with a history of seizures. Since most of the lesions were peripheral, they represented a benign cause of seizures that could be treated surgically. In fact, two of our four patients have

been free of seizures since the tumor was surgically removed. MA may be considered as a forme fruste of neurofibromatosis (1). Demonstration of MA in a patient should alert the neuroradiologist, neurologist, and neurosurgeon to investigate further by means of appropriate chromosomal analyses for abnormalities in chromo-

somes 17 and 22 that are found in type 1 and 2 neurofibromatosis, respectively. It should be realized, however, that MA has also been described in patients without other evidence of neurofibromatosis, such as those described herein (3,4). MA can be differentiated from the usual pattern of abnormalities seen in the Sturge-Weber syndrome, in which thick cortical calcifications and ipsilatera! loss of brain parenchyma volume exist.

In

Sturge-Weber

syndrome,

the

dystrophic calcifications in the middle layers of the cerebral cortex are associated with overlying leptorneningeal venous angiomata (6). These features should

allow

differentiation

of

Sturge-

Weber syndrome from MA. Other abnormalities may cause peripheral calcification with associated edema and enhancement with contrast material dude meningitis

at CT.

These

meningioma, (sarcoid

abnormalities

in-

granulomatous or

tuberculous),

and infiltrating intraparenchymal ma with calcification (7). MA

glioshould

June

1991

.

__

I

,0

;‘ .

.

..

‘ -

.

T T:

4f

---s

.

e. (a) Axial

unenhanced

f-

CT image

demonstrates

a peripheral,

Figure 2. Patient 4. white matter in the lesion (arrows). (c, portion of the lesion, men shows fibrous cation (arrowhead)

left posterior temporal lobe (arrow). (b) Axial enhanced d) Dual-echo axial MR image (2,400/20-100) demonstrates and the hypointensity (arrow in c and d) of the mass. proliferation within the full thickness of the leptomeninges (hematoxylin-eosin stain; original magnification, XlO).

liferation

in

also

(arrows)

be

considered

are

In summary, with

patients

seizures.

At CT,

most

white

matter.

in

accurate

the

is a benign, of

Volume

be seen

MA will

with

calcification.

We

Meurmann this

Note

the

correlation

(arrows) (f) Histopathologic

thank

for their

with

Esther

Prince

clues

are of

3

have be

Kunishio

original

manuscript.

edema

of the

magnification,

K, Yamamoto

Histopathologic ingioangiomatosis

in

X 30).

Y, Sunami

N, et al.

investigation of a case of mennot associated with von

Recklinghausen’s

I.

2.

which

cause

3.

Worcester-Drought emy WH. Multiple

Kuzniecky

A.

References

important

correctable

stain;

5.

of the

MA,

between

4.

associated

pattern of the peripheral a and d. (e) Histopathologic speciperivascular psammomatous calcifishows perivascular fibroblastic pro-

associated specimen

(hematoxylin-eosin

assistance

with

the gyriform-enhancing matter, the hyperintense

disease.

Surg

Neurol

1987;

27:575-579.

pe-

edema

diagnosis

#{149} Number

compiling

lesions

a hyperintense associated These

in pa-

Judy

lesion

CT image demonstrates the edema of the white

(arrowheads)

Acknowledgments:

At

their

U 179

will

imaging,

surgically

seizures.

imaging

calcifications

calcified

neurofibromato-

lesions

MR with

may

their

demonstrate

riphery,

psammomatous

and

with

consistent

will

these

without

sis. Most

with

present.

MA or

T2-weighted

matter

when

characteristics tients

gray

granularly

C. Dickson meningeal

WEC, McMenand perineural

tumors with analagous changes in the glia and ependyma. Brain 1937; 60:85-117. Halper J, Scheithauer BW, Okazaki H, Laws ER Jr. Meningo-angiomatosis: a report of six cases with special reference to the occurrence of neurofibrillary tangles. J Neuropathol Exp Neurol 1986; 45:426-446. Kasantikul V. Brown WJ. Meningioangiomatosis in the absence of von Recklinghausen’s disease. Surg Neurol 1981; 15:71-75.

Magnetic

R. Melanson

D, Robitaille

resonance

gioangiomatosis.

Can

Y, Heir

imaging of meninJ Neurol Sri 1988;

15:161-164. 6.

Gean

AD,

radiology. nosis-imaging

7.

Taveras

M.

In: Taveras

tumors

phakomatoses

intervention.

pincott, 1988; 1-3. Rubenstein, Lucieu gy:

The

JM. Ferrucci

of the

J. central

6. Bethesda, Md: Armed thology. 1972.

in

J. eds.

Philadelphia:

Atlas

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nervous

Forces

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patholo-

system.

Institute

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Diag-

Fasc

of Pa-

#{149} 821