Brain MRI abnormalities in ataxia-telangiectasia.
ABSTRACT Ataxia-telangiectasia (AT) is a rare autosomal recessive disorder, initially characterized by normal brain magnetic resonance imaging (MRI).
In a 34-year-old woman patient with AT, MRI revealed extensive and diffuse white matter dismyelination, T1 and T2 hypointense lesions, T1 hypointense but T2 hyperintense lesions, and numerous dilated telangiectases upon gadolinium enhancement.
In our patient, brain MRI confirmed extensive extracerebellar lesions in AT.
Our report broadens the spectrum of brain MRI abnormalities in AT and supports the hypothesis on cerebrovascular abnormalities occurring in later stages of AT.
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ABSTRACT: BACKGROUND: Susceptibility-weighted imaging (SWI) is a relatively new magnetic resonance (MR) technique that exploits the magnetic susceptibility differences of various tissues, such as blood, iron and calcification, as a new source of contrast enhancement. This pictorial review is aimed at illustrating and discussing its main clinical applications. METHODS: SWI is based on high-resolution, three-dimensional (3D), fully velocity-compensated gradient-echo sequences using both magnitude and phase images. A phase mask obtained from the MR phase images is multiplied with magnitude images in order to increase the visualisation of the smaller veins and other sources of susceptibility effects, which are displayed at best after post-processing of the 3D dataset with the minimal intensity projection (minIP) algorithm. RESULTS: SWI is very useful in detecting cerebral microbleeds in ageing and occult low-flow vascular malformations, in characterising brain tumours and degenerative diseases of the brain, and in recognizing calcifications in various pathological conditions. The phase images are especially useful in differentiating between paramagnetic susceptibility effects of blood and diamagnetic effects of calcium. SWI can also be used to evaluate changes in iron content in different neurodegenerative disorders. CONCLUSION: SWI is useful in differentiating and characterising diverse brain disorders.Insights into imaging. 06/2011; 2(3):335-347.