Wall shear stress in intracranial aneurysms and adjacent arteries

Hemodynamic parameters play an important role in aneurysm formation and growth. However, it is difficult to directly observe a rapidly growing de novo aneurysm in a patient. To investigate possible associations between hemodynamic parameters and the formation and growth of intracranial aneurysms, the present study constructed a computational model of a case with an internal carotid artery aneurysm and an anterior communicating artery aneurysm, based on the CT angiography findings of a patient. To simulate the formation of the anterior communicating artery aneurysm and the growth of the internal carotid artery aneurysm, we then constructed a model that virtually removed the anterior communicating artery aneurysm, and a further two models that also progressively decreased the size of the internal carotid artery aneurysm. Computational simulations of the fluid dynamics of the four models were performed under pulsatile flow conditions, and wall shear stress was compared among the different models. In the three aneurysm growth models, increasing size of the aneurysm was associated with an increased area of low wall shear stress, a significant decrease in wall shear stress at the dome of the aneurysm, and a significant change in the wall shear stress of the parent artery. The wall shear stress of the anterior communicating artery remained low, and was significantly lower than the wall shear stress at the bifurcation of the internal carotid artery or the bifurcation of the middle cerebral artery. After formation of the anterior communicating artery aneurysm, the wall shear stress at the dome of the internal carotid artery aneurysm increased significantly, and the wall shear stress in the upstream arteries also changed significantly. These findings indicate that low wall shear stress may be associated with the initiation and growth of aneurysms, and that aneurysm formation and growth may influence hemodynamic parameters in the local and adjacent arteries.

Chinese Stroke Association guidelines for clinical management of cerebrovascular disorders: executive summary and 2019 update of clinical management of intracerebral haemorrhage

Aim This evidence-based guideline aims to present current and comprehensive recommendations for the diagnosis and management of spontaneous intracerebral haemorrhage(ICH).Methods A formal literature search was conducted on MEDLINE(1 January 1990 to 30 June 2019).Data were synthesised using evidence tables.The members of the working group met by teleconference to update and formulate data-based recommendations.The recommendations are graded according to levels of evidence grading algorithm of the Chinese Stroke Association.The guideline draft has been reviewed by Chinese Stroke Association Stroke Council Guideline Writing Committee.Results Evidence-based guideline is proposed for the management of patients with ICH.The focus of the guideline is divided into the diagnosis and aetiology of ICH,management of ICH in emergency department,surgical treatment for removal of hematoma,management of complications and prevention of secondary ICH.Conclusions This guideline provides a framework for ICH management.Early active and reasonable treatment may improve the clinical outcome of patients.