The effective visualization of aneurysms is a very important issue in neurosurgery. However it is difficult to display both the aneurysm with sufficient detail, and the vessel network of the brain at the same time. This work offers a solution to both of these problems, applying the concept of focus and context to texture-based volume rendering. A flexible application has been developed, allowing different focus and context techniques to be used. This paper concentrates on the evaluation of the system by a group of neurosurgeons.