Purpose: To create criteria for detecting dural ectasia on MR or CT images in adult Marfan patients.
Methods: Images were analyzed using a workstation. Parameters that predicted dural ectasia were included in our criteria.
Results: Major criteria include: (1) width of dural sac below L5 > width above L4; (2) anterior sacral meningocele. Minor criteria include: (1) L5 nerve root sleeve diameter > 6.5 mm and (2) S1 scalloping > 3.5. Dural ectasia exists if 1 major or 2 minor criteria are present.
Conclusion: MR and CT diagnose dural ectasia with high specificity and sensitivity. Our criteria accurately diagnose dural ectasia in adult Marfan patients.