A patient with Marfan syndrome presented with enlargement of lumbosacral spinal canal with a bulky meningocele, and a fusiform aneurysm of the ascending aorta. In Marfan syndrome, the presence of a meningocele is extremely rare, but 60% of the patients develop cardio-vascular complications (a frequent cause of death). MRI is the imaging technique of choice for the diagnosis of meningocele and aortic aneurysm.