MR OF HEREDITARY HEMORRHAGIC TELANGIECTASIA - PREVALENCE AND SPECTRUMOF CEREBROVASCULAR MALFORMATIONS

PURPOSE: Our goal was to describe the prevalence and types of cerebral vascular malformations (CVMs) seen with MR imaging in patients,vith h ereditary hemorrhagic telangiectasia (HHT). METHODS: We reviewed retro spectively the brain MR images of 184 consecutive patients with HHT. C atheter angiography was performed in 17 patients with CVMs detected on MR images. RESULTS: MR imaging revealed 63 CVMs in 42 patients. Class ic arteriovenous malformations (n = 10) had a conspicuous network of v essels with flow voids and enlarged adjacent pial vessels. Apparent ve nous malformations (n = 5) were best seen after administration of cont rast material as a prominent vessel coursing through normal brain pare nchyma. Indeterminate vascular malformations (n = 48) had a spectrum o f appearances characterized by variable combinations of heterogeneous signal intensity, enhancement, or hemosiderin. Angiography in 17 patie nts revealed 47 CVMs. Forty-six were arteriovenous malformations (AVMs ), including 25 CVMs not seen with MR imaging and 21 CVMs that by MR c riteria included 8 AVMs and 13 indeterminate vascular malformations, A ngiography confirmed 1 venous malformation seen with MR imaging but fa iled to detect 3 indeterminate lesions revealed by MR imaging, CONCLUS ION: MR imaging of a large cohort of consecutive patients with HHT rev ealed a CVM prevalence of 23% (42/184). Most CVMs (48/63) have an atyp ical appearance for vascular malformations on MR images, Angiographic correlation suggests that MR imaging underestimates the prevalence of CVMs and that the majority of indeterminate CVMs, despite their variab le MR appearance, are AVMs.