We present numerical simulations of blood flow through a brain vascular aneurysm with an artificial stent using Smoothed Particle Hydrodynamics (SPH). The aim of this work is to analyze how the flow into an aneurysm c...We present numerical simulations of blood flow through a brain vascular aneurysm with an artificial stent using Smoothed Particle Hydrodynamics (SPH). The aim of this work is to analyze how the flow into an aneurysm changes using different stent configurations. The initial conditions for the simulations were constructed from angiographic images of a real patient with an aneurysm. The wall shear stresses, pressure and highest velocity within the artery, and other particular quantities are calculated which are of medical specific interest. The numerical simulations of the cerebral circulation help doctors to determine if the patient’s own vascular anatomy has the conditions to allow arterial stenting by endovascular method before the surgery or even evaluate the effect of different stent structure and materials. The results show that the flow downstream the aneurysm is highly modified by the stent configuration and that the best choice for reducing the flow in the aneurysm is to use a completely extended Endeavor stent.展开更多
Although aortic aneurysms are the most common type encountered clinically, they do not span the entire spectrum of possible aneurysms of the cardiovascular system. As cross sectional imaging techniques with cardiac co...Although aortic aneurysms are the most common type encountered clinically, they do not span the entire spectrum of possible aneurysms of the cardiovascular system. As cross sectional imaging techniques with cardiac computed tomography and cardiac magnetic resonance imaging continue to improve and becomes more commonplace, once rare cardiovascular aneurysms are being encountered at higher rates. In this review, a series of uncommon, yet clinically important, cardiovascular aneurysms will be presented with review of epidemiology, clinical presentation and complications, imaging features and relevant differential diagnoses, and aneurysm management.展开更多
Background: Patients with Abdominal Aortic Aneurysm can be treated with two different surgical methods: Open repair (OR) or Endovascular Aortic Repair (EVAR). These two different treatments can probably result in diff...Background: Patients with Abdominal Aortic Aneurysm can be treated with two different surgical methods: Open repair (OR) or Endovascular Aortic Repair (EVAR). These two different treatments can probably result in different sense of Health related Quality of life, both in a short term and a long term perspective. The purpose of this prospective study was to examine patients’ Health related Quality of life after surgical treatment of Abdominal Aortic Aneurysm over two years using different instruments for the observations. Methods: Patients were invited consecutively to answer questionnaires before operation, and 1, 12 and 24 months after surgery. The study was conducted by using the Health related Quality of life questionnaires Short Form (SF-36) and Nottingham Health Profile (NHP). 76 patient (40 in the OR and 36 in the EVAR group) participated in the study. The mean age in the OR group were 68 years, range 52 - 80 and in the EVAR group 75 years, range 65 - 85. The results from these two groups of patients were compared to a matched reference group. Results: Patients treated with EVAR rated their Health related Quality of life significantly lower in the domain of Mental Health and Mental Component Score in relation to a matched reference population before surgery. This difference was not present two years after intervention. After one month Health related qualities of life were worse for the OR group. After two years significant improvements in relation to baseline were observed only among patients in the OR group. No such long-term benefits were seen in the EVAR group. Conclusions: As the component mental health seemed to be impaired for these study group before surgery in relation to the matched reference group, nursing and doctors care actions may be of importance during the pre-operative phase. In the short perspective Health related Quality of life is worse for OR patients than the EVAR group but in the long term perspective improvements beyond preoperative status can only be seen with OR patients.展开更多
Objectives: Endovascular abdominal aortic aneurysm repair (EVAR) is a common procedure for abdominal aortic aneurysm (AAA), based on minimal invasiveness compared with open surgical repair (OSR). However, general anes...Objectives: Endovascular abdominal aortic aneurysm repair (EVAR) is a common procedure for abdominal aortic aneurysm (AAA), based on minimal invasiveness compared with open surgical repair (OSR). However, general anesthesia can cause considerable perturbations in patients with AAA undergoing operative repair. The aim of this study was to compare the incidence of myocardial ischemic events in association with hemodynamic changes during EVAR and OSR under general anesthesia. Methods: We retrospectively reviewed the anesthetic and medical records of patients who underwent elective abdominal aortic aneurysm repair. ST segment changes on electrocardiography and hemodynamic changes were reviewed by the attending physicians. Results: Among 120 patients, EVAR and OSR were performed in 81 and 39 patients, respectively. There were no significant differences in preoperative morbidity between the two groups. The amount of estimated blood loss was significantly lower in EVAR than OSR. The incidence of ST?segment changes in the two groups (EVAR: 16%, OSR: 23%) was not statistically different. ST segment changes occurred mainly postoperatively at resolution of anesthesia in EVAR, compared with intraoperatively in OSR. ST segment changes were mostly accompanied by tachycardia in EVAR patients, whereas they were associated with hypotension in OSR. Conclusion: Our results demonstrated a comparable incidence of perioperative ST segment changes under general anesthesia in EVAR and OSR. Patients who undergo EVAR and develop tachycardia are at risk of myocardial ischemia at resolution of anesthesia.展开更多
Objective The purpose of this study was to quantify the vascular angle change due to intracranial stent placement and its effect on hemodynamics. Methods Fifteen patients with a wide-necked anterior communicating arte...Objective The purpose of this study was to quantify the vascular angle change due to intracranial stent placement and its effect on hemodynamics. Methods Fifteen patients with a wide-necked anterior communicating artery aneurysm were treated with stent-assisted coiling. Centerlines of the parent vessels were calculated and determined the exact change in展开更多
文摘We present numerical simulations of blood flow through a brain vascular aneurysm with an artificial stent using Smoothed Particle Hydrodynamics (SPH). The aim of this work is to analyze how the flow into an aneurysm changes using different stent configurations. The initial conditions for the simulations were constructed from angiographic images of a real patient with an aneurysm. The wall shear stresses, pressure and highest velocity within the artery, and other particular quantities are calculated which are of medical specific interest. The numerical simulations of the cerebral circulation help doctors to determine if the patient’s own vascular anatomy has the conditions to allow arterial stenting by endovascular method before the surgery or even evaluate the effect of different stent structure and materials. The results show that the flow downstream the aneurysm is highly modified by the stent configuration and that the best choice for reducing the flow in the aneurysm is to use a completely extended Endeavor stent.
文摘Although aortic aneurysms are the most common type encountered clinically, they do not span the entire spectrum of possible aneurysms of the cardiovascular system. As cross sectional imaging techniques with cardiac computed tomography and cardiac magnetic resonance imaging continue to improve and becomes more commonplace, once rare cardiovascular aneurysms are being encountered at higher rates. In this review, a series of uncommon, yet clinically important, cardiovascular aneurysms will be presented with review of epidemiology, clinical presentation and complications, imaging features and relevant differential diagnoses, and aneurysm management.
文摘Background: Patients with Abdominal Aortic Aneurysm can be treated with two different surgical methods: Open repair (OR) or Endovascular Aortic Repair (EVAR). These two different treatments can probably result in different sense of Health related Quality of life, both in a short term and a long term perspective. The purpose of this prospective study was to examine patients’ Health related Quality of life after surgical treatment of Abdominal Aortic Aneurysm over two years using different instruments for the observations. Methods: Patients were invited consecutively to answer questionnaires before operation, and 1, 12 and 24 months after surgery. The study was conducted by using the Health related Quality of life questionnaires Short Form (SF-36) and Nottingham Health Profile (NHP). 76 patient (40 in the OR and 36 in the EVAR group) participated in the study. The mean age in the OR group were 68 years, range 52 - 80 and in the EVAR group 75 years, range 65 - 85. The results from these two groups of patients were compared to a matched reference group. Results: Patients treated with EVAR rated their Health related Quality of life significantly lower in the domain of Mental Health and Mental Component Score in relation to a matched reference population before surgery. This difference was not present two years after intervention. After one month Health related qualities of life were worse for the OR group. After two years significant improvements in relation to baseline were observed only among patients in the OR group. No such long-term benefits were seen in the EVAR group. Conclusions: As the component mental health seemed to be impaired for these study group before surgery in relation to the matched reference group, nursing and doctors care actions may be of importance during the pre-operative phase. In the short perspective Health related Quality of life is worse for OR patients than the EVAR group but in the long term perspective improvements beyond preoperative status can only be seen with OR patients.
文摘Objectives: Endovascular abdominal aortic aneurysm repair (EVAR) is a common procedure for abdominal aortic aneurysm (AAA), based on minimal invasiveness compared with open surgical repair (OSR). However, general anesthesia can cause considerable perturbations in patients with AAA undergoing operative repair. The aim of this study was to compare the incidence of myocardial ischemic events in association with hemodynamic changes during EVAR and OSR under general anesthesia. Methods: We retrospectively reviewed the anesthetic and medical records of patients who underwent elective abdominal aortic aneurysm repair. ST segment changes on electrocardiography and hemodynamic changes were reviewed by the attending physicians. Results: Among 120 patients, EVAR and OSR were performed in 81 and 39 patients, respectively. There were no significant differences in preoperative morbidity between the two groups. The amount of estimated blood loss was significantly lower in EVAR than OSR. The incidence of ST?segment changes in the two groups (EVAR: 16%, OSR: 23%) was not statistically different. ST segment changes occurred mainly postoperatively at resolution of anesthesia in EVAR, compared with intraoperatively in OSR. ST segment changes were mostly accompanied by tachycardia in EVAR patients, whereas they were associated with hypotension in OSR. Conclusion: Our results demonstrated a comparable incidence of perioperative ST segment changes under general anesthesia in EVAR and OSR. Patients who undergo EVAR and develop tachycardia are at risk of myocardial ischemia at resolution of anesthesia.
文摘Objective The purpose of this study was to quantify the vascular angle change due to intracranial stent placement and its effect on hemodynamics. Methods Fifteen patients with a wide-necked anterior communicating artery aneurysm were treated with stent-assisted coiling. Centerlines of the parent vessels were calculated and determined the exact change in
