VENOUS ANEURYSMS - MR DIAGNOSIS WITH THE LAYERED GADOLINIUM SIGN

Objective: Our goal was to present MR findings in venous aneurysms and introduce the ''layered gadolinium'' sign as an ancillary diagnostic finding. Method: Gadolinium-enhanced MR images of three patients with retroperitoneal venous aneurysms were retrospectively reviewed. Prior to MRI, venous aneurysm had been suspected clinically in only one pati ent. Surgical correlation was available in one patient. A phantom was constructed and imaged to investigate the cause of the layered gadolin ium sign. Results: A gradation of signal intensity, the layered gadoli nium sign, was observed in three patients with venous aneurysms on pos tcontrast T1-weighted images. The anterior portion of the aneurysms de monstrated high signal intensity separated by a sharp interface from t he low signal intensity posterior region. Unenhanced time-of-flight MR venography, color Doppler, and duplex sonography failed to demonstrat e flow in the patient with surgical proof. Conclusion: The layered gad olinium sign may be helpful in the diagnosis of venous aneurysm and in differentiating these masses from solid neoplasms.