Capillary telangiectasias of the pons. Does diffusion-weighted MR increase diagnostic accuracy?
Introduction
Capillary telangiectasias refer to the cerebrovascular malformations of the central nervous system. They were first described by Russell and Rubinstein in 1959 [1]. Histologically they are composed of multiple thin walled capillary-like vessels separated by regular cerebral parenchyma which distinguishes them from cavernomas. Their most common localization is the brainstem, especially the pons. Much less common localizations are the cerebral hemispheres or the spine. The lesions have diameters ranging from several millimeters to 2 centimeters.
Their true incidence is not known. Based on autopsy reports they have a prevalence of approximately 0.4% representing 16–20% of all vascular malformations of the pons [2].
The clinical value of this lesion is still in discussion. In most cases they have a benign history. It is not clear yet if they lead to relevant clinical symptoms. Many different symptoms are mentioned in literature. Besides dizziness, nausea, ataxia, speech disorder, hyperreflexia, ptosis or paresthesia there is – to our knowledge – only one published case with a malign fatal progress [3].
Major complications such as ischemic infarcts, bleedings or change of local perfusion are rare. Most bleedings seem to arise from other associated vascular malformations such as cavernomas.
Magnetic resonance imaging (MRI) represents the standard of reference in diagnostic imaging of capillary telangiectasias. In most cases they are not detectable by catheter angiography or computed tomography (CT). Several typical and atypical features were described for MRI. But even using MRI the diagnosis is sometimes ambiguous. The lesions can be confused with other lesions, especially infectious and ischemic, as well as demyelinating or metastatic disease.
Because of the usually benign progress of capillary telangiectasias and the lack of therapeutic options invasive procedures should be avoided. To enable this a high specificity of diagnostic imaging methods is requested.
In a case report Fellner et al. already demonstrated the hypointense signal characteristics of a capillary telangiectasia using diffusion-weighted imaging (DWI) [4].
In this study we wanted to assess the accuracy and diagnostic benefit of DWI in characterizing capillary telangiectasias. Therefore we compared the MRI images of 18 patients with capillary telangiectasia to 130 consecutive patients with different pons lesions.
Section snippets
Material and methods
148 consecutive patients (83 male, 65 female, age ranging from 6 to 84 years (median age 56.6 ± 18.5 standard deviation)) with infratentorial lesions were evaluated retrospectively. In all patients the performed sequences used identical measurement parameters. To assess the characteristic appearance of capillary telangiectasias they were compared to other relevant pathologies located within or near the pons (e.g. neoplasms, inflammatory lesion, demyelinating disease, ischemic lesion).
According to
Results
Details of the visual evaluation are listed in Table 1 followed by ROI evaluation in Table 2.
The visual evaluation (Table 1) revealed hypointense (11/18) or isointense (7/18) signal of capillary telangiectasias compared to the surrounding pons tissue (Fig. 1a) in T1-weighted images. In T2-weighted images the lesions appeared isointense (6/18) or hyperintense (12/18) (Fig. 1b). Contrast enhanced T1-weighted images showed hyperintense signal in all capillary telangiectasias having an irregular
Discussion
Cerebral vascular malformations are classified into arteriovenous malformation (AVM), developmental venous anomalias (DVA), cavernomas and capillary telangiectasias. AVM, DVA and cavernomas have well known MRI criteria. AVM and DVA are detectable by angiography while cavernomas and capillary telangiectasias are usually not visible.
The current literature describes divergent criteria for MR imaging in capillary telangiectasias. Just a solid contrast uptake in T1-weighted sequences seems to be a
Conclusion
Regarding brainstem lesions, a high signal intensity in T1-weighted contrast enhanced images in combination with low signal intensity in DWI is an important and useful MRI indicator for a capillary telangiectasia. Especially the use of DWI enables a better differentiation of capillary telangiectasias to metastases or demyelinating lesions, which can show very similar appearance in standard MR sequences. Therefore, in the imaging of pontine lesions, we would recommend to apply diffusion-weighted
Conflict of interest
None.
References (12)
- et al.
Pathology of tumors of the nervous system
(1959) - et al.
Intracerebral venous angioma: case report and review
Arch Neurol
(1978) - et al.
Clinically aggressive diffuse capillary telangiectasia of the brain stem: a clinical radiologic-pathologic case study
AJNR Am J Neuroradiol
(1999) - et al.
A new criterion in the diagnosis of capillary telangiectasis of the brain stem
Röfo
(2004) - et al.
Presumed capillary telangiectasia of the pons: MRI and follow-up
Eur Radiol
(2000) - et al.
Vascular malformations of the central nervous system
J Neuropathol Exp Neurol
(1995)
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Magnetic resonance imaging of pontine capillary telangectasia
2011, European Journal of RadiologyCitation Excerpt :It was reported the case of a patient with paresis of the right sixth and seventh cranial nerves [24]. In the reviewed literature no symptoms have been reported previously which could be unequivocally attributed to a brainstem CTS, although most of the patients are imaged for neurological symptoms of the posterior fossa [9,18,24]. Because of the hypothesized association between CTS and cavernous haemangiomas it is possible that haemorrhagic complications may be due to the associated cavernomas and not to bleeding of the CTS [18,24].
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