ABSTRACT
Objectives: To investigate the morphological characteristics of pericallosal artery aneurysms (PAAs) and to analyze the morphological influence factor of PAA rupture. Methods: From January 2013 to May 2017A,40 consecutive patients with PAA admitted to the Department of Neurosurgery,Xuanwu Hospital, Capital Medical University were enrolled retrospectively. They were diagnosed by whole brain vascular DSA before treatment. Forty patients were divided into ruptured group (n = 22 with 22 aneurysms) and the unruptured group (n = 18 with 23 aneurysms). The morphological parameters of the number of aneurysms in two-dimensional or three-dimensional rotational angiography included diameter, height, width, aneurysm neck width,diameter of parent arteries, and inflow angle of aneurysms, and the aspect ratio, size ratio and length-width ratio (aneurysm diameter/aneurysm width) of each aneurysm were further calculated. The aspect ratio was calculated using aneurysm height/aneurysm neck width and aneurysm diameter/aneurysm neck width, respectively, and the size ratio was calculated using aneurysm height/parent artery diameter and aneurysm diameter/parent artery diameter, respectively. The differences of morphological parameters of PAAs were compared and multivariate logistic regression analysis was performed to preliminarily investigate the morphology of influencing factors of PAA rupture. Results: (1) There were no significant differences in age, male, multiple aneurysms, and risk factors for cardiocerebrovascular diseases between the two groups (all P>0.05). (2) The proportion of irregular aneurysms and the length-width ratio of aneurysms in the rupture group were higher than those in the unruptured group. The difference between the groups was statistically significant (90.9% [20/22] ts. 39. 1% [9/23],χ2 =8. 01); 1. 35 ±0. 36 vs. 1. 01 ±0. 22,t= -3. 85; all P 0. 05). (3) Amongthe 45 aneurysms,the proportion of A3 anterior bifurcation aneurysms was 53.3% (24 aneurysms), and the proportion of the ruptured group and unruptured group was 68. 2% (15/22) and 39. 1% (9/23) respectively. There were no significant differences between the groups (χ2 =0. 381,P = 0. 051). (4) The mean length-width ratio in 45 PAAs was 1. 18. using this as the defined value, the length-width ratio was converted into a two-category variable,and the PAA rupture was used as the dependent variable. The univariate analysis of the morphological parameters in the length-width ratio (> 1. 18) and the irregular aneurysm were included in the multivariate logistic regression analysis. The results showed that the length-width ratio was >1.18 (OR,1.84,95% CI 1.42-28. 11,P =0. 016),and irregular aneurysms (OR,2. 06,95% CI 1. 66-37. 11, P = 0. 009) were the independent risk factor for PAA rupture. Conclusions: The ratio of height-length-width of PAAs and the irregular morphology of aneurysms suggest that PAAs are prone to rupture. The evaluation of PAA morphological parameters should be emphasized in clinical practice.
ABSTRACT
Introduction Pericallosal artery (PA) aneurysms represent 2 to 9% of all intracranial aneurysms, and their management remains difficult. Objective The aim of the present study is to describe the case of an adult woman with subarachnoid hemorrhage and bilateral PA aneurysm in mirror position. Case Report A 46-year-old woman was referred to our institution 20 days after a sudden severe headache. She informed that she was treating her arterial hypertension irregularly, and consumed 20 cigarettes/day. The patient was neurologically intact at admission. A non-contrast computed tomography (CT) on the first day of the onset of the symptoms revealed hydrocephaly and subarachnoid hemorrhage (Fisher III). An angio-CT/digital subtraction arteriography showed bilateral PA aneurysms in mirror position. The patient was successfully treated with surgery via the right interhemispheric approach (because the surgeon is right-handed); the surgeon performed the proximal control with temporary clipping, and introduced an external ventricular drain at the end of the surgery. The patient was discharged on the fourth postoperative day without any additional neurological deficits or ventricular shunts. Conclusion Ruptured PA aneurysm is a surgically challenging aneurysm due to the many anatomical nuances and risk of rebleeding. However, the operativemanagement of ruptured bilateral PA aneurysms is feasible and effective.