The rupture risk of unruptured intracranial aneurysms is known to be dependent on the size of the aneurysm. subgroup analysis for individuals with visualized PCoA shown that larger throat diameter (p?=?0.018) and shorter 67469-75-4 IC50 ICA bifurcation to aneurysm range (p?=?0.011) were significantly associated with rupture. Intracerebral hemorrhage was associated with smaller volume, larger maximum height, and smaller aneurysm angle, in addition to lateral projection, male sex, and lack of hypertension. We 67469-75-4 IC50 found that shorter ICA bifurcation to aneurysm range is definitely significantly associated with PCoA aneurysm rupture. This is a new physically intuitive parameter that can be measured easily and therefore be readily applied in medical practice to aid in the evaluation of individuals with PCoA aneurysms. Intro The guidelines for management of unruptured intracranial aneurysms remains one-dimensional even as more and more unruptured aneurysms undergo treatment . As a result of the International Study of Unruptured Intracranial Aneurysms (ISUIA), treatment decision of unruptured intracranial aneurysms is currently centered primarily on the size of the aneurysm C. However, a recent large prospective natural history study of unruptured aneurysms carried out from the Unruptured Cerebral Aneurysm Study (UCAS) of Japan offers underscored the importance of not only size, but also the location and morphology of the aneurysm in predicting rupture risk . Specifically, rupture risk was significantly elevated in aneurysms of the anterior and posterior communicating arteries, and even small aneurysms in these locations experienced a relatively high risk of rupture. Several groups including our own have begun to study contribution of morphological characteristics to the treatment decision of unruptured aneurysms in a systematic and location specific manner. Previous studies of large cohorts of mixed aneurysms have reported that variables such as the 67469-75-4 IC50 aspect ratio, undulation index, and size ratio are associated with ruptured aneurysms C. Looking at aneurysms in a location specific manner, our group found that aspect ratio, flow angle, Rabbit Polyclonal to Cyclin H (phospho-Thr315) and parent-daughter to be highly associated with middle cerebral artery aneurysm rupture . Matsukawa et al. recently reported that rupture of anterior communicating artery aneurysms was associated with anterior dome projection, the presence of blebs, and size 5 mm . Posterior communicating artery (PCoA) aneurysms are the second most common intracranial aneurysm and represent half of all internal carotid artery aneurysms . Furthermore, though the rupture risk is similar to other anterior blood circulation aneurysms , smaller size alone 67469-75-4 IC50 in PCoA aneurysms does not necessarily correlate with decreased risk of rupture. In a review of PCoA aneurysms, the overall prevalence of aneurysms measuring less than 10 mm was 87.5%, and as many as 85.6% of ruptured PCoA aneurysms were less than 10 mm . Thus, it is obvious that size alone is not a reliable predictor of rupture risk and other physical characteristics of the aneurysm must be considered. We present a large sample of posterior communicating aneurysms that were assessed using a diverse array of morphological variables to determine the parameters associated with ruptured posterior communicating artery aneurysms. Methods Ethics Statement The study was approved by the Brigham and Women’s Hospital Institutional Review Table. Written consent from your patients was waived by the Institutional Review Table. Patient selection The study population consisted of all patients with a diagnosis of posterior communicating artery (PCoA) aneurysm treated at the Brigham and Women’s Hospital during a 7-12 months period between 2005 and 2012. Aneurysms that underwent reoperation, those that were 67469-75-4 IC50 associated with arteriovenous malformations, or those that lacked preoperative CT angiography (CTA) were excluded. Demographic and clinical information were collected from medical records. In particular, patient data on risk factors generally associated with aneurysm development or aneurysm rupture were collected, including smoking status, family history, presence of multiple aneurysms, history of hypertension, and prior history of aneurysm rupture/SAH. The study was approved by the Institutional Review Table. Reconstruction of 3D models As described in our prior study , we utilized 3D Slicer (referred as Slicer in the following text), an open source, multi-platform visualization and image analysis software , . Pre-operative CT angiography (CTA) images were utilized to generate composite three-dimensional (3D) models of the aneurysm and surrounding vasculature. All CTAs were performed on a Siemens? SOMATOM Definition scanner with slice thickness of 0.75 mm and.