Objectives: Loeys-Dietz syndrome is a recently described autosomal dominant connective tissue disorder caused by heterozygous mutations in the genes encoding for transforming growth factor β receptors 1 and 2. It is characterized by aggressive vascular pathology with aortic and arterial tortuosity, aneurysm formation and a propensity for early dissection. We describe a single study, whole body MR approach for paediatric assessment of the known associated cardiovascular, skeletal, brain and spine abnormalities.
Methods: Eight children (age range 0.5 - 14 years) with known Loeys-Dietz syndrome had MRI studies performed on a 1.5T scanner. General anaesthesia was utilized less than 6 years of age with initial X-rays to exclude cervical spine instability. The imaging sequences included: cardiac cine anatomical and functional imaging, phase-contrast imaging of the aortic valve and major vessels, whole body MR angiography (using a single injection of 0.4cc/kg intravenous gadolinium), brain and spinal anatomical imaging and 3D time-of-flight imaging of the circle of Willis.
Results: Vascular abnormalities demonstrated included: 5 moderate to severe aortic root dilatation; 5 tortuous aortic arch, descending thoracic or abdominal aorta; 7 tortuous innominate, carotid, vertebral or intracranial arteries; and 2 with abdominal aortic branch involvement. Associated skeletal, brain and spine abnormalities included: 1 craniosynostosis; 2 hypertelorism; 1 pectus excavatum; 1 anterior corpus callosal hypoplasia; 1 arachnoid cysts; 3 cervical spine anomalies; 2 scoliosis; and 3 lumbosacral dural ectasia.
Conclusion: Our whole body MR approach allows for comprehensive assessment of the complex range of cardiovascular, skeletal, brain and spine abnormalities associated with Loeys-Dietz syndrome.