Clinical Study Of Surgical Clipping Of Intracranial Aneurysms

Intracranial saccular aneurysms are acquired vascular abnormalities that cause outpouching of the arterial wall.Although most intracranial aneurysms go undetected,acute rupture can be a devastating consequence associated with substantial rates of morbidity and mortality(hazard rate of death 20～30%).Clinical management of unruptured aneurysm patients is a current topic of debate.In order to avoid the devastating consequence of rupture,preventative treatment for unruptured intracranial aneurysms may be recommended.In the past 20 years,the evolution of imaging techniques and neurosurgical operative microscope have led to a higher detection rate of unruptured intracranial aneurysms.However,because of the concerns for risks of treatment,only a small number of unruptured intracranial aneurysms have been treated surgically at present and most of the aneurysm surgeries in China are ruptured cases.The decision to treat or not to treat an unruptured aneurysm must take into account the risks associated with intervention.Among these risks of treatment,uncontrolled intraoperative aneurysmal rupture is one of the most serious complications of microsurgical clipping of intracranial aneurysms and remains a well-recognized risk that can significantly affect the patient’s chance for a good recovery.Therefore,it is important to assess the factors associated with intraoperative rupture and develop strategies of dealing with it.This study retrospectively examined patients with intracranial aneurysms treated surgically in two medical centers and assessed the factors associated with intraoperative rupture.As the neurosurgeon’s surgical experience is one of the most important factors affecting a patient’s outcome after an intraoperative rupture of an aneurysm,the authors also evaluated the relationship of the neurosurgeon’s experience with the rate of intraoperative rupture.Meanwhile,unruptured aneurysm cases treated with neurosurgical methods in these two medical centers were identified and evaluated.PartⅠ Intraoperative rupture in the surgical treatment of patients with intracranial aneurysm:risk factors and managementPurpose:This clinical study was conducted to evaluate factors influencing intraoperative rupture of intracranial aneurysms during microsurgery.Methods:A retrospective analysis of 331 patients with intracranial aneurysms treated by clipping surgery in two medical centers was done.The surgical technique and the outcome of patients were reviewed.Results:There were 19 instances of intraoperative rupture in this study,6 in group 1 and 13 in group 2.There seem to be a significant difference in the intraoperative rupture rate on the basis of their clinical grade at admission.Grade 0-Ⅲ aneurysms had a lower intraoperative rupture rate(P<0.05).Posterior cerebellar artery and blister-like internal carotid artery aneurysms were more liable to rupture intraoperatively.The intraoperative rupture rate was greater in ruptured than unruptured aneurysms.There did not seem to be a significant difference in the intraoperative rupture rate on the basis of neurosurgeon’s experience.As the neurosurgeon’s experience increased,the number of ruptures before opening dura matter and during clip application decreased,whereas the number occurring during dissection increased.Conclusions:Aneurysms with history of subarachnoid hemorrhage are at high risk for an intraoperative premature rupture.This study found no significant influence of intraoperative rerupture during open surgical clipping on patient’s outcome.Intraoperative rupture is an unavoidable danger in aneurysm surgery that does not vanish with the increasing surgical experience of the neurosurgeon.Indication of surgical intervention is vital to lowering the rate of intraoperative rupture during the neurosurgeon’s early experience.Part Ⅱ Surgical Treatment of Patients with Unruptured Intracranial AneurysmsPurpose:To analyze the risks of microsurgical clipping of unruptured intracranial aneurysms and to further understand the optimal treatment strategies for an individual patient.Methods:The clinical data of 162 patients with 177 unruptured intracranial aneurysms from two medical centers were retrospectively analyzed.Data were collected with regard to age,sex,presence of symptoms,location and size of the aneurysms,surgical complications and postoperative 6 month outcomes.Results:150 patients with 165 aneurysms were treated in group 1 and 12 patients with 12 aneurysms were treated in group 2.There seem to be a significant difference between group 1 and group 2 in percentage of incidental and symptomatic aneurysms.There was not significant difference for outcome between patients<60 and those>60 years of age.There was a high probability of a good outcome for patients with small and normal aneurysms or anterior circulation aneurysms.The outcome of group 1 was better than that of group 2,however there was not significant difference in outcome between two groups.Conclusions:Aneurysm diameter of>15 mm and posterior circulation aneurysms were found to be significant predictive factors for poor outcome.Although there was not significant difference in outcome between two groups,there seem to have a poor outcome in low-volume center.This result should be taken into account when making a balanced decision on whether to proceed with surgery in an individual patient with an unruptured aneurysm in low-volume center.