Detection of dural ectasia in diagnosis of Marfan's syndrome

Marfan's syndrome is an inherited connective tissue disorder that affects many organ systems and has widespread phenotype expression. The diagnosis is therefore made by phenotype assessment. Dural ectasia has been classified as a major diagnostic criterium with a prevalence of over 90% in patients with Marfan's syndrome. The objective of this study determine the feasibility of performing CT angiographic examination of aorta and large vessels for dural ectasia grading in a single CT exam of patients with Marfan's syndrome.

7 examinations in Marfan patients were performed of which 6 were CTA. In all exams the aorta was evaluated and simultaneously the lumbosacral region of the spine was well delineated. We performed calculation of spinal canal (SCI) and dural sac (DSI) indices and also qualitative grading of dural sac involvement.

In 4 patients both SCI (> 4,50) and DSI (> 3,75) fulfil the diagnostic criteria of Marfan's syndrome. In 1 patient complete spondyloptosis was detected.

Whole body CT examination is the perfect tool for both aorta and spinal canal evaluation. Despite differences in spinal canal grading methods in all of our patients significant changes of the spinal canal in the lumbosacral region were detected. Dural ectasia is easy to detect and quantify and may therefore be used as a sensitive and specific sign of Marfan's syndrome.