MR-ANGIOGRAPHY AND MR-IMAGING OF SYMPTOMATIC VASCULAR MALFORMATIONS

Purpose: To define the appearance of peripheral vascular malformations at magnetic resonance angiography (MRA) and assess the role of magnet ic resonance imaging (MRI) and MRA in the investigation of these lesio ns, Patients and methods: Fourteen patients (aged 8-51 years) with cli nical evidence of a vascular malformation were referred for MRI and MR A, performed on a 0.5T GE Vectra superconducting system (International General Electric, Slough, UK), Multisection T1-weighted spin-echo and T2-weighted fast spin-echo pulse sequences were performed, with an in version recovery fast spin-echo sequence in two cases, Two-dimensional time of Eight (2-D TOF) and/or 2-D phase contrast (PC) MRA was perfor med in 13 cases, Eleven patients had digital subtraction angiography ( DSA) using a Phillips Integris V3000 digital angiographic unit, The fi ndings at MRA and MRI were compared with the catheter angiograms, and the effective diagnostic input of MRA and MRI was determined, Results: MRA demonstrated major feeding vessels and multiple intra-lesional ve ssels in relation to the high flow lesions, features absent in the lon flow lesions, However, small feeding vessels to the AVMs were not cle arly identified, MRI gave a clear demonstration of the anatomical exte nt of all lesions, AVMs (it = 6) and venous malformations (it = 6) wer e reliably distinguished, the former containing multiple serpentine si gnal voids on T1- and T2-weighted imaging, the latter being hyperinten se to fat on T2-weighted images, Two other high-flow lesions diagnosed clinically as vascular malformations appeared solid on R IRI, and mer e diagnosed histologically as a carotid body tumour and an angiomyolip oma, Conclusion: Although 2-D TOF MRA can distinguish AVMs from venous malformations, the technique adds little extra practical information to the diagnostic process, and cannot compete with catheter angiograph y for the detailed demonstration of AVM feeding vessels, These lesions can also be characterized using spin-echo sequences, though the prima ry role of MRI is to demonstrate their anatomical extent.