Anatomic features predictive of complete aneurysm occlusion can be determined with three-dimensional digital subtraction angiography.

BACKGROUND AND PURPOSE

Complete occlusion of intracranial aneurysms is the goal of endovascular treatment and is influenced by several aneurysm-related anatomic factors. The anatomic features of aneurysms can be characterized by three-dimensional reconstructed images by use of rotational digital subtraction angiography (3D-DSA). The purpose of this study was to determine the anatomic factors that could help predict complete endosaccular packing of cerebral aneurysms by use of 3D-DSA and to design a simple scoring system to predict the difficulty of achieving complete occlusion of the aneurysm.

METHODS

Forty-seven patients with 47 intracranial berry (<12 mm) aneurysms underwent 3D-DSA. Aneurysms were subsequently treated by endosaccular packing with coils. The following aneurysm-related anatomic parameters were measured on 3D-DSA images: largest diameter, neck size, dome-to-neck ratio, shape, and relationship to the neighboring artery. The relationship between each parameter and the rate of successful treatment was determined, and a score used to rate difficulty of attaining occlusion (ie, difficulty score) was developed on the basis of the identified predictors of successful treatment. Subsequently, we assessed the correlation between the score and the rate of successful occlusion.

RESULTS

Four anatomic parameters correlated significantly with the rate of successful occlusion: neck size (P =.014), shape (P=.042), dome-to-neck ratio (P <.01), and relationship to neighboring artery (P=.025). The difficulty score based on two parameters (dome-to-neck ratio and relationship to neighboring artery) significantly correlated with the occlusion rate (r = 0.63, P <.01).

CONCLUSION

In this population, the difficulty score based on 3D-DSA findings provides useful information for prediction of successful endovascular treatment for intracranial aneurysms.