Neurosurg.Rev.
19111996)119-121

Clinical and radiological evaluation of angiographically
occult, calcified intracranial vascular malformation.
Case report
Siileyman Baykal ~, Sava~ Ceylan 1, Hasan Din~ 2, Kayhan Kuzeyli 1, Eray Soylev 1,
Haydar UsuP, and Fadil Aktiirk ~
Departments of ~Neurosurgery and 2Radiology, K T U Medical Faculty, Trabzon,
Turkey

Abstract
In this study, we present an angiographically occult, calcified intracranial vascular malformation. This lesion is rare
and has some therapeutic difficulties and different approaches by authors. In this article, we also discuss the
clirfical, radiological characteristic features of this lesion.
We pay attention on the totally calcified malformation.

Keywords: Angiography, calcification, magnetic resonance
imaging.

history of complex partial seuzures insufficiently
controlled by antiepileptic drugs. The physical and
neurological examination on admission was normal.
Plain films show an irregular calcification in the left
middle fossa (Figure 1). M R I show a serpentine lesion in the left temporal lobe with mixed isointens
region on T2-weighted images (Figure 2a, b). The
angiogram was without shunting, blush, or abnormal vessels (Figure 3a, b). The MR-angio was also
normal (Figure 4). The diagnosis was totally calcified vascular malformation.

1 Introduction
The term "angiographically occult intracranial vascular malformation" (OVM) is applied to a group of
intracranial vascular malformations (arteriovenous,
cavernous, venous angiomas or capillary telangiectases) [1, 2, 3, 4, 7, 8, 12, 16, 17]. In the literature, the
term thrombosed malformations and occult intracranial vascular malformations have been used
interchangeably [7]. Magnetic resonance imaging of
these patients can often help to suggest the diagnosis of angiographically occult vascular malformations with increased confidence [10, 11, 14, 15].
In this report, we present a patient with radiologieally verified angiographically occult, calcified vascular malformation and discuss her clinical and magnetic resonance imaging (MRI) characteristics.

2 Case report
A 22-year-old woman presented with a 16-year
9 1996by Walterde Gruyter& Co. Berlin.NewYork

Figure 1. Lateral plain skull film showing a huge calcification in the suprasellar region. Note an irregular and heterogen appearance,

120

Baykal et al., Clinicaland radiologicalevaluation of OVM

Figure 2. T2-weighted axial (a) and coronal (b) MR images, showing an irregular hypointens lesion located in the left
temporal lobe,
The patient and her family did not admit surgical
exploration. Her seizures were controlled by carpamazepine and valproic acid and discharged.

3 Discussion
Because of common radiographic findings and a
spectrum of common histopathological findings,
thrombosed arteriovenous malformations and occult vascular malformations seem to have similar
presentations and prognosis and indeed may represent the same disease entity [7, 10, 12]. The responsible mechanisms for the partial or complete thrombosis of angiographicallyoccult intracranial vascular
malformations are arteriosclerosis, embolism, hem-

orrhage with secondary vascular compression, slow
blood flow, intravascular turbulency due to the tortuosity of the vessels, and hypercoagulability [12,13].
LOBATOet al. reported some calcification in approximately 10% of patients with OVM's on skull x-ray
films [1, 9, 12]. They also demonstrated calcification
in 24% of patients on the nonenhanced CT scan
[12]. Two cases of dystrophic intracranial calcification due to arteriovenous malformations were reported by Yu et al. They explained the probable pathogenetic mechanism for calcification as a result of
"cerebral steal" by the arteriovenous malformation
[18]. We are not certain whether calcification in our
case is explained by the proposed mechanism in our
case, In this lesion, OVM was calcified. This huge

Figure 3. Normal angiogramswere shownon the anteroposterior (a) and lateral
(b) projection.

Figure 4. MR-angiogramwas normal.
Neurosurg. Rev. 19 (1996)

Baykal et al., Clinical and radiological evaluation of OVM

121

calcification is shown by plain x-ray a n d MRI. In the
literature review, a similar lesion was not d e m o n strated.

and M R I findings may differentiate these two lesions.

H e a d a c h e and seizure disorders are the most comm o n clinical presentation of OVM's [5, 6, 15]. In addkion, episodic progressive worsening is the second
most clinical p r e s e n t a t i o n [15]. These clinical presentations may suggest the presence of a low grade
n e o p l a s m but, the duration of the patient's seizures

It was postulated that CT scan a n d M R I a p p e a r to
be a b o u t equally sensitive in the detection of these
lesions, a l t h o u g h the M R I is p r o b a b l y slightly more
specific [14, 15]. B u t if calcification is present, C T
scan is superior to M R I for the evaluation of calcified lesion. A n g i o g r a p h y is essential for its vascular
nature of this lesion.

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519-22
Submitted July 24, 1994. Revised February 10, 1995.
Accepted February 14, 1995.
Dr. Siileyman Baykal
KTfJ Tip Fak01tesi
N6rosirtirji Klinigi
61080 Trabzon
Turkey