Evaluation of cerebrovascular lesions with 3D-DSA

Abstract

Purpose: Three dimensional digital subtraction angiography (3D-DSA) is a new tool which combines the benefits of both conventional cerebral angiography and three dimensional computed tomographic angiography (3D-CTA). In the present study, cerebrovascular lesions were evaluated with 3D-DSA. Method: Five occlusive cerebrovascular lesions, 31 cerebral aneurysms, and 2 arteriovenous malformations (AVMs) were evaluated with 3D-DSA. Angiography was performed using the Seldinger method in all cases. To produce three dimensional vascular images for the 3D-DSA system, a single plane C-arm was rotated by 200° with infusing 15 to 20 ml of the contrast material. The data captured from 44 mask images and 44 contrast images were then transferred to a computer workstation and reconstructed three-dimensionally. Results: 3D-DSA demonstrated the following benefits as compared with conventional cerebral angiography: (1) The size of the aneurysm and its neck could be accurately measured, with a difference of less than 0.5mm between measurements taken from the computer screen of the 3D-DSA system and the operation field. (2) The lesion and the surrounding vascular structure could be recognized three dimensionally, which was of great benefit for simulating the operation. In cerebral aneurysms, the shape of the aneurysm, location of the bleb, and relationship between the aneurysm and the parent arteries were demonstrated clearly. In AVMs, the architectures of the feeders, drainers, and nidus were also demonstrated clearly, even when located peripherally. (3) An endovascular image was made available. 3D-DSA also demonstrated the following benefits as compared with 3D-CTA: (1) Visualization of the arteries, including those peripheral, was very clear, which provided satisfactory information regarding the aneurysmal neck and parent arteries for performing the operation. (2) Images of the cerebral arteries were not disturbed by the cerebral veins or skull base bones. As a result, lesions in the internal carotid artery, such as IC-PC aneurysms, were clearly demonstrated without any disturbance of the skull base bone or cavernous sinus. (3) Fine arterial branches and perforating arteries could be visualized. One disadvantage of the 3D-DSA was that bony structure information could not be provided. In cases of paraclinoid and basilar bifurcation aneurysms, 3D-DSA should be combined with 3D-CTA to clarify the relationship between these lesions and the skull base bone. Conclusions: Although 3D-DSA requires the Seldinger method to obtain clear images, it offers various benefits which are very useful for evaluating such cerebrovascular lesions as cerebral aneurysms and AVMs, as well as for simulating the operation.