Operative confirmation of three-dimensional computed tomographic and magnetic resonance imaging of cerebrovascular pathology.

The conventional neuroradiological evaluation of aneurysms and arteriovenous malformations employs computed tomography (CT), magnetic resonance imaging (MRI), and detailed cerebral angiography. These techniques may be inadequate to define fully the cerebrovascular anatomy in patients with giant aneurysms or with arteriovenous malformations (AVMs) located near so-called eloquent brain structures. Therefore, we examined the usefulness of three-dimensional (3-D) MRI and CT images of the brain and cerebral vessels for predicting operative anatomical findings in selected cases of complex cerebrovascular pathology. In six of nine (67%) patients with giant aneurysms undergoing direct surgical treatment, the 3-D images were confirmed to be accurate, and they furnished information that is not available by conventional imaging. In three of these nine (33%) patients, failure of the 3-D images to predict operative findings accurately could be directly related to inappropriate imaging technique or to anatomical findings below the limit of resolution for CT or MRI. In 13 of 19 (68%) patients with an AVM, the 3-D images were considered helpful for treatment selection or planning, primarily because they enhanced the understanding of the relationship of the AVM nidus to brain structures of known functional significance. The results of our initial experience with 3-D imaging of cerebrovascular pathology are described in this report.