Magnetic resonance angiography for anterior midline aneurysms

Over an 18-month period (June 1994-December 1994), all patients presenting with a subarachnoid haemorrhage (SAH) were considered for magnetic resonance angiography (MRA) as part of their investigation. Our experience to date leads us to believe that anterior midline aneurysms can be confidently and rapidly diagnosed with MRA alone without recourse to invasive intra-arterial digital subtraction angiography. This assumes, of course, that images can be obtained; some patients cannot be investigated by MR because of the presence of metallic foreign bodies; in a small proportion without anaesthesia the images will be so degraded as to be valueless and some patients will be judged unsuitable from the outset because of their clinical state. In 30 patients, a diagnosis of an anterior midline aneurysm was made on MRA and 21 of these patients underwent surgery on the MR images alone. Surgery, undertaken via a midline approach in these 21 patients, confirmed the MR findings.