Iwama T, Hashimoto N, Takagi Y, Tsukahara T, Hayashida K
Department of Neurosurgery, National Cardiovascular Center, Osaka, Japan.
Neurosurgery. 1997 Jan;40(1):53-9; discussion 59-60. doi: 10.1097/00006123-199701000-00011.
When the efficacy of extracranial/intracranial bypass surgery is discussed, can we include the patients with extensive collateral circulation through the bypass and those with poor collateral circulation in the same group? The bypass function should be determined not by the patency of the bypass but by the extent of collateral circulation through the bypass. We retrospectively analyzed our patients to determine whether the extent of bypass flow can be predicted from the results of preoperative studies.
In 51 hemispheres of 44 consecutive patients who underwent extracranial/intracranial bypass surgery, correlation between the extent of bypass flow and the preoperative results of angiographic and stimulated cerebral blood flow studies were investigated.
The bypass function is highly predictable with the aid of preoperative studies. In 11 hemispheres that showed both retrograde spontaneous circulation via leptomeningeal anastomoses and decreased reactivity to acetazolamide of cerebral blood flow in an area distal to the arterial lesion, collateral circulation through the bypass developed well and reactivity to acetazolamide improved. In all of 13 hemispheres that showed normal reactivity to acetazolamide, the bypass was patent but the collateral circulation did not develop well. In only 4 of 24 hemispheres with spontaneous antegrade circulation distal to the lesion was there satisfactory collateral circulation through the bypass.
Our results indicate that improvement of the hemodynamic status by bypass surgery should be expected only in patients with both spontaneously developed leptomeningeal anastomoses and decreased reactivity to acetazolamide.
在讨论颅外/颅内搭桥手术的疗效时，我们能否将通过搭桥有广泛侧支循环的患者和侧支循环差的患者归为同一组？搭桥功能不应由搭桥的通畅情况决定，而应由通过搭桥的侧支循环范围决定。我们对患者进行回顾性分析，以确定术前研究结果能否预测搭桥血流量。
在连续接受颅外/颅内搭桥手术的44例患者的51个半球中，研究搭桥血流量与术前血管造影和刺激脑血流研究结果之间的相关性。
借助术前研究，搭桥功能具有高度可预测性。在11个半球中，通过软脑膜吻合出现逆行性自发循环，且动脉病变远端区域脑血流对乙酰唑胺的反应性降低，通过搭桥的侧支循环发育良好，对乙酰唑胺的反应性改善。在对乙酰唑胺反应正常的所有13个半球中，搭桥通畅，但侧支循环发育不佳。在病变远端有自发顺行循环的24个半球中，只有4个半球通过搭桥有令人满意的侧支循环。
我们的结果表明，只有在既有自发形成的软脑膜吻合又对乙酰唑胺反应性降低的患者中，才有望通过搭桥手术改善血流动力学状态。
