Schaller Bernhard
Neurological Surgery, University Hospital, Münster, Germany.
Neurol Neurochir Pol. 2007 Sep-Oct;41(5):457-71.
Selected patients with acute or continual ischaemic symptoms from occlusions or inaccessible stenotic lesions of the internal carotid artery or middle cerebral artery have been considered candidates for an extracranial-intracranial (EC-IC) bypass procedure. Hitherto, no effectiveness of this surgical therapeutic option for various patient subgroups could be found in a large international randomized trial, and therefore various guidelines give negative recommendations for its usefulness. The aim of the present report was to analyze clinical effectiveness of EC-IC bypass for cerebral revascularization in haemodynamic subgroups of patients with advanced occlusive cerebrovascular disease in the anterior cerebral circulation.
A computerized database search from November 1985 to November 2001 was performed. Language restriction was done for English, French and German. Reports dealing with EC-IC bypass surgery for cerebral revascularization in case of advanced cerebrovascular disease in the anterior cerebral circulation were reviewed when appropriate. Studies were included if they contained valuable data on clinical state, pre- and postoperative haemodynamic state, surgical outcome and follow-up.
The postoperative outcome related to death or stroke depended mainly on preoperative haemodynamic subgroups (CBF/CBV; OEF). The final functional status was worse the more the CBF/CBV ratio and OEF increased. Perioperative risk for death (0.6%) or stroke (2%) during the first month after surgery was similar to the death or stroke rate during the following 2 to 12 months after surgery. The overall risk profile for subsequent death or stroke of surgically treated patients is significantly better within the first 12 months than that of conservatively treated patients (1.3% vs. 3.6% per year). Neurological function was improved over the preoperative state in 84% of the patients and was unchanged in 6%. Postoperatively, modified Rankin scale score was 0-1 in 90% of patients and 2 in 1% of patients. Long-term patency was excellent, with 1% failure rate per year following the first year after surgery.
Neurological function and subsequent stroke attributable to haemodynamic insufficiency in patients with symptomatic carotid occlusion or severe stenosis are improved significantly by EC-IC bypass surgery if the brain area corresponding to the impaired neurological function remains viable. The haemodynamic parameters observed for patients who experience improved neurological function or diminished stroke risk profile after EC-IC-bypass surgery contain both significantly elevated OEF and CBF/CBV. Therefore haemodynamic profile represents an important indicator for EC-IC bypass surgery and gives a good rationale for new trials conducted in a subgroup of patients selected on the basis of their haemodynamic profile.
患有急性或持续性缺血症状的特定患者，其颈内动脉或大脑中动脉存在闭塞或难以处理的狭窄病变，被视为颅外-颅内（EC-IC）旁路手术的候选对象。迄今为止，在一项大型国际随机试验中未发现这种手术治疗方案对不同患者亚组有效，因此各种指南对其效用给出了负面推荐。本报告的目的是分析在大脑前循环中患有晚期闭塞性脑血管疾病的患者血流动力学亚组中，EC-IC旁路手术用于脑血运重建的临床有效性。
进行了从1985年11月至2001年11月的计算机数据库检索。语言限制为英语、法语和德语。对涉及大脑前循环晚期脑血管疾病时进行EC-IC旁路手术以实现脑血运重建的报告进行了适当审查。若研究包含有关临床状态、术前和术后血流动力学状态、手术结果及随访的有价值数据，则纳入研究。
与死亡或中风相关的术后结果主要取决于术前血流动力学亚组（脑血流量/脑血容量；氧摄取分数）。脑血流量/脑血容量比值和氧摄取分数增加得越多，最终功能状态越差。术后第一个月内死亡（0.6%）或中风（2%）的围手术期风险与术后接下来2至12个月内的死亡或中风发生率相似。手术治疗患者随后死亡或中风的总体风险状况在最初12个月内明显优于保守治疗患者（每年1.3%对3.6%）。84%的患者神经功能较术前状态有所改善，6%的患者神经功能未改变。术后，90%的患者改良Rankin量表评分为0 - 1分，1%的患者评分为2分。长期通畅情况良好，术后第一年之后每年的失败率为1%。
对于有症状的颈动脉闭塞或严重狭窄患者，若对应神经功能受损的脑区仍有活力，通过EC-IC旁路手术可显著改善因血流动力学不足导致的神经功能及后续中风情况。在接受EC-IC旁路手术后神经功能改善或中风风险状况降低的患者中观察到的血流动力学参数，包括氧摄取分数和脑血流量/脑血容量均显著升高。因此，血流动力学状况是EC-IC旁路手术的一个重要指标，为基于血流动力学状况选择的患者亚组中开展的新试验提供了充分理由。
