Hereditary hemorrhagic telangiectasia (HHT) manifested by spinal
and vascular malformations in the nasal mucosa and brain.
The lesions in the cervical and thoracic cord are consistent with
intramedullary foci of subacute hemorrhage associated with cord
edema (figure 1). The left frontal lesion may be a small cavernous
hemangioma or what has been called an "indeterminate"
cerebrovascular malformation (vide infra) (figure 2). The lesion in
the left nasal cavity is consistent with a vascular malformation
and is the cause of recurrent epistaxis, the most common clinical
manifestation of HHT (figure 3).
Hereditary hemorrhagic telangiectasia, also known as
Rendu-Osler-Weber disease, is a hereditary disorder characterized
by telangiectasias of the skin and mucosa, and vascular
malformations in multiple organs. The primary lesion of HHT is the
mucocutaneous telangiectasia, a vascular dysplasia typified by
dilated and convoluted veins that often connect directly to dilated
The other prominent vascular lesion in HHT
is the arteriovenous fistula or malformation (AVM), which consists
of a direct connection between arteries and veins but is much
larger than the telangiectasia.1
HHT is inherited in an
autosomal dominant pattern. Recent genetic studies have linked
mutations in the endoglin gene, a cell-surface component of the
beta transforming growth factor, to be responsible for some
familial forms of HHT.2
The clinical diagnosis of HHT is
based on the presence of any two of the following: recurrent
epistaxis, telangiectasias, evidence of familial inheritance, and
A variety of neurologic manifestations (including headache,
transient ischemia, stroke, seizure, intracerebral and subarachnoid
hemorrhage, and brain abscess) have been attributed to pulmonary
arteriovenous fistula (PAVF), primary AVM in the brain, AVM of the
spinal cord, or portosystemic encephalopathy in patients with
HHT.3 Any given patient may have one or more of these
lesions. A PAVF may result in neurologic symptoms because of
vascular shunting, air embolism, paradoxical embolism, or brain
abscess. Various cerebral vascular malformations have been
described in patients with HHT and include telangiectasia,
cavernous hemangioma, pial AVM, saccular aneurysm, and
carotid-cavernous fistula.3 Primary cerebral vascular
malformations can cause headache, seizures, and stroke after they
hemorrhage into the brain or subarachnoid space. Approximately
two-thirds of all neurologic manifestations of HHT are attributed
to complications of PAVF and one-third are due to cerebral or
Fulbright et al5 have reported the prevalence and
types of 63 cerebral vascular malformations seen on MR imaging and
angiography in 42 patients with HHT. In this series,
"indeterminate" cerebral vascular malformations made up 76% of the
lesions and are a heterogeneous group of lesions. These
malformations are small (5 to 15 mm) ovoid lesions that variably
enhance, and may have high, low, or mixed signal intensity on
T2-weighted images. Some of these lesions have features of
cavernous malformations, but Fulbright and colleagues believe that
they represented small AVMs with abnormal arteriovenous
architecture characteristic of vascular lesions found in other
organs in patients with HHT. The left frontal lobe lesion in our
patient is similar to the "indeterminate" vascular malformation
described by these authors.
Vascular malformations of the spinal cord are much rarer central
nervous system manifestations of HHT. In a review of the neurologic
manifestations of HHT, Roman et al3 found only 17
documented cases of vascular malformations of the spinal cord
reported in the literature. Using selective spinal cord
angiography, Djindjian et al6,7 found 7 cases of spinal
AVM in HHT among 150 medullary angiomas. These lesions were usually
found in the dorsal thoracic cord. Transient paresis, sensory
disturbances, anal and bladder dysfunction, muscle wasting, and
complete paraplegia may result from shunting of blood, ischemia,
mass effect, subarachnoid hemorrhage, or thrombosis. The cord
lesions in this case lack one of the typical MR imaging findings
described for spinal AVMs, since there were no serpiginous
intradural vascular flow voids encircling the cord. In the case of
a small AVM, the nidus is not usually seen on MR imaging, although
the enlarged feeding arteries and draining veins are often evident
and diffuse increased signal in the cord on T2-weight-ed images is
also common. This latter finding has been attributed to venous
hypertension.8 We believe that the two intramedullary
lesions in this case probably represent minute "indeterminate"
vascular malformations, as described by Fulbright et al5
in the cerebrum of patients with HHT, or cavernous hemangiomas.
- Guttmacher AE, Marchuk DA, White RI Jr: Hereditary hemorrhagic
telangiectasia. N Eng J Med 333:918-924, 1995.
- Rius C: Cloning of the promoter region of human endoglin, the
target gene for hereditary hemorrhatic telangiectasia type 1.
Blood 12:4677-4690, 1998.
- Roman G, Fisher M, Perl DP, Poser CM: Neurological
manifestations of hereditary hemorrhagic telangiectasia
(Rend-Osler-Weber Disease): Report of 2 cases and review of the
literature. Ann Neurol 4:130-144, 1978.
- White RI Jr, Lynch-Nyhan A, Terry P, et al: Pulmonary
arteriovenous malformations: Techniques and long-term outcome of
embolotherapy. Radiology 169:663-669, 1988.
- Fulbright RK, Chaloupka JC, Putman CM, et al: MR of hereditary
hemorrhagic telangiectasia: Prevalence and spectrum of
cere-brovascular malformations. Am J Neuroradiol
- Djindjian R: Spinal vascular malformations. J
- Djindjian R: Angiography of the Spinal Cord.
University Park Press; Baltimore, 1970.
- Friedman DP, Flanders AE,Tartaglino LM: Vascular neoplasms and
malformations, ischemia, and hemorrhage affecting the spinal cord:
MR imaging and findings. AJR Am J Roentgenol 162:685-692,