3D Rotational Digital Subtraction Angiography May Underestimate Intracranial Aneurysms: Findings from Two Basilar Aneurysms

L.-D Jou,M.E Mawad,A Mohamed,D.H Lee

doi:10.3174/ajnr.a0652

Abstract

3D digital subtraction angiography (DSA) allows clinicians to review intracranial aneurysms and other vascular lesions. We report 2 basilar aneurysms that were imaged by both 3D DSA and DynaCT. These 2 techniques produced very different aneurysm appearances. Anterior portions of the aneurysms were invisible on 3D DSA but were revealed by DynaCT. These aneurysms appeared to have been flattened by image artifacts in 3D DSA. Pulsation and gravity are 2 possible causes of aneurysm underestimation.

Highlights

Digital subtraction angiography (DSA) has been the “gold standard” for many vascular and cerebrovascular imaging studies. 3D rotational DSA enables clinicians to review intracranial aneurysms and other vascular lesions thoroughly in an angiography study or during an interventional procedure. 3D rotational DSA was shown to perform better than either MR or CT angiography in 1 experimental study[1] in which time-offlight MR angiography underestimated aneurysm volumes, whereas CT angiography overestimated
We describe 2 cases of basilar aneurysms for which there are considerable differences in aneurysm volume and morphology between 3D DSA and DynaCT (Siemens Medical Solutions, Erlangen, Germany).[5]
In DynaCT, 22 mL of same contrast agent diluted by the saline (25%) was injected at 1 mL/s, and 543 projections within 220° were acquired for reconstruction

Summary

Introduction

Digital subtraction angiography (DSA) has been the “gold standard” for many vascular and cerebrovascular imaging studies. 3D rotational DSA enables clinicians to review intracranial aneurysms and other vascular lesions thoroughly in an angiography study or during an interventional procedure. 3D rotational DSA was shown to perform better than either MR or CT angiography in 1 experimental study[1] in which time-offlight MR angiography underestimated aneurysm volumes, whereas CT angiography overestimated. Insufficient contrast influx can introduce image artifacts in 3D DSA.[3] For example, parent vessels near an aneurysm may appear stenotic.[4] In this report, we describe 2 cases of basilar aneurysms for which there are considerable differences in aneurysm volume and morphology between 3D DSA and DynaCT (Siemens Medical Solutions, Erlangen, Germany).[5] For 3D DSA, 30 mL of contrast agent (Omnipaque 300; GE Healthcare, Princeton, NJ) was injected at 2.5 mL/s for 12 seconds, and 275 projections were acquired in 220° within 10 seconds to reconstruct 3D images.

Results

Conclusion