Surgical views from three-dimensional digital subtraction angiography for the planning of aneurysm surgery

To develop a semi-automatic protocol helping to present directly and quickly three-dimensional digital subtraction angiography (3D-DSA) data in an orientation that reproduces exactly the neurosurgeon's intraoperative view.

Post-processing of 3D-DSA data (volume-rendering) was performed on an Integris workstation (Philips, Best); surgical views were obtained by visualization of the patient's head through a frontopterional approach: the 3D volume was turned 135 degrees in the sagittal plane (around the X axis) and rotated by 45 degrees and 60 degrees in the coronal plane (around the Y axis). The protocol was evaluated on a consecutive series of nine patients who had ruptured or asymptomatic anterior circulation aneurysms requiring surgical treatment. Frontopterional views of angiographic 3D data were compared with intraoperative views.

The proposed semi-automatic algorithm is simple, fast and reproducible, and displays the 3D data in an orientation identical to the intraoperative views. The surgical anatomy of the anterior communicating artery was best reproduced with a coronal rotation of 60 degrees , with a coronal rotation of 45 degrees for the other aneurysm locations. In each case, the surgical reconstructions allowed a more accurate analysis of the vascular anatomy around the aneurysm, and facilitated pre- and perioperative planning.

The present protocol displays angiographic 3D data in a projection that exactly reproduces the vascular anatomy through a frontopterional approach. It may help neurosurgeons to better anticipate any potential difficulties during access and clip-positioning arising due to the specific vascular anatomy of a given patient.