We have all – patients and physicians alike – come to take the capabilities of diagnostic imaging technology for granted; indeed, our expectations of that technology continue to increase – higher resolution, faster acquisition times, less artifact – the list of demands goes on and on. However, it is scarcely within the span of a generation that lesions considered occult in one imaging modality can now be diagnosed based on features that are pathognomonic in another modality. Young clinicians embarking on their careers at this time may be unaware, for example, that cerebral cavernous malformations with their distinctive appearance on magnetic resonance images were not that long ago considered to be angiographically occult arteriovenous malformations.
I offer this brief historical detail because readers of this volume are about to embark on an amazing three-dimensional visual journey of the circulation of the brain and neck that very few years ago would have been impossible. From the perspective of a neurosurgeon, the appreciation of the vascular system afforded by these images is priceless. Not only does three-dimensional rotational angiography improve the accuracy of diagnosis, it considerably enhances our ability to optimize treatment for patients with challenging neurovascular disorders. Preoperative planning is immeasurably improved by the ability to rotate these images in space to view the posterior regions of vessels that can even be difficult to view intra operatively.