Aneurysm wall inflammation

Dynamic Volume Change Rate and Aspect Ratio Are Correlated to the Formation of an Irregular Morphology of Unruptured Intracranial Aneurysm

OBJECTIVE

The aim of this research was to study the factors influencing the formation of intracranial aneurysms with irregular morphology by observing the dynamic volume change rate of intracranial unruptured aneurysms and other aneurysm characteristics.

METHOD

Sixty-five unruptured intracranial aneurysms of 51 consecutive patients from 1 center were included in this study. All patients underwent a dual-source computed tomography electrocardiogram-gated 4-dimensional computed tomography angiography examination. The original data at the end of the scan were reconstructed, and 20 sets of data packages through a cardiac cycle with 5% interval were obtained. Data packages were processed by a 3-dimensional software workstation to obtain 20 sets of images and dynamic diagrams. The volume of each aneurysm in the 20 sets of images was measured, and the volume change was calculated by a specific formula. The other data features of the aneurysm such as aneurysm neck, aneurysm height, aspect ratio (AR), location at bifurcation, and clinical features such as age, sex, hypertension history, type 2 diabetes history, smoking history, family history, multiple aneurysm history, and subarachnoid hemorrhage history, were documented in detail. After single factor analysis data, logistic regression analysis of the meaningful indicator was conducted to study the predictive factors of irregular aneurysms.

RESULTS

Of the 65 aneurysms, 25 possessed an irregular shape and 40 were of regular shape; 51 were anterior circulatory aneurysms and 14 were posterior circulatory aneurysms. Single factor analysis showed that AR (P = 0.001), volume change rate (P = 0.002), and location of aneurysm at the bifurcation (P = 0.038) of the vessel were significantly correlated with irregular aneurysms, but not correlated with age, sex, hypertension history, type 2 diabetes history, smoking history, family history, multiple aneurysm history, and subarachnoid hemorrhage history. Multifactor analysis showed that volume change rate greater than 30% (P = 0.008; odds ratio, 6.934) and AR greater than 1.4 (P = 0.004; odds ratio, 8.258) were independent correlative factors of the formation of intracranial aneurysm with irregular shape.

CONCLUSION

The volume change rate and AR are independent correlative factors of the formation of intracranial aneurysm with irregular shape.

The Size of Ruptured Intracranial Aneurysms : A 10-Year Series from a Single Center

PURPOSE

There is a controversy concerning the risk of rupture of small intracranial aneurysms. We sought to determine the size and morphological features of ruptured intracranial aneurysms.

MATERIAL AND METHODS

The hospital files and images from all patients referred during one decade (2007-2016) to a specialized neurovascular center were retrospectively reviewed. Neck diameter, fundus depth and width as well as neck width based on catheter angiography were measured. Aneurysm morphology was classified as either regular, lobulated, irregular or fusiform.

RESULTS

A total of 694 consecutive patients with aneurysmal subarachnoid hemorrhage (aSAH) were identified (65.9% female, median age 54.3 years). The anterior communicating artery (AcomA) was the most frequent location of ruptured aneurysms. The medians for aneurysm depth, width and neck diameter were 5 mm, 4.5 mm and 3 mm, respectively. A regular contour of the aneurysm sac was found in 19%.

CONCLUSION

The majority of aSAH are caused by small intracranial aneurysms. There is no safety margin in terms of small aneurysm size of regular shape without daughter aneurysms. Treatment should also be offered to patients with small, regularly shaped intracranial aneurysms, together with an empirical risk-benefit assessment.