Applications of Dynamic CT Angiography

Background: Dynamic CT angiography (dCTA) provides augments traditional CTA with temporal resolution and has been demonstrated to influence operative planning in skull base surgery.

Methods: 325 dynamic CTA cases from Brigham and Women’s Hospital were reviewed for indication of study, findings, and comparison to other modalities of imaging.

Results: The Department of Neurosurgery ordered the majority of dCTA tests (72.6%). The most frequent indication to obtain a dCTA was pre-operative planning (60%); resection of skull base tumors comprised the majority of these pre-operative orders (92.3%). It was also used to evaluate new neurological symptoms (20.6%). Of these, the most common symptoms prompting dCTA orders included headaches (14.9%), visual field deficits (11.9%), altered mental status (9%), and seizures (9%). The most commonly visualized vascular lesions were partial (20.9%) and full vascular occlusions (9%). Another indication for dCTA was for post-operative imaging for vascular malformations (9.2%) and tumors (2.5%). Finally, dCTA was used to evaluate ambiguous abnormal findings observed on other imaging modalities (7.7%). Cerebral dCTA ruled out abnormal findings visualized on other imaging modalities (68%) more frequently than it confirmed them (32%); these findings included vascular malformations such as arteriovenous malformation and arteriovenous fistulas (43.8%) and aneurysms (31.2%).

Conclusions: Cerebral dCTA is an evolving new technology with a diverse spectrum of potential applications. In addition to its role in guiding preoperative planning for skull base surgical cases, dynamic CTA offers excellent spatial and temporal resolution for assessment of vascular lesions.