Park Sang Kyu, Shin Yong Sam, Lim Yong Cheol, Chung Joonho
Department of Neurosurgery, Incheon St. Mary's Hospital, Catholic University of Korea, Seoul, Korea.
Neurosurgery. 2009 Aug;65(2):281-5; discussion 285-6. doi: 10.1227/01.NEU.0000348296.09722.2F.
Resection of the anterior clinoid process (ACP) for the clipping of an internal carotid-posterior communicating artery aneurysm is rarely needed. However, preoperative awareness of the necessity of anterior clinoidectomy is essential for safe clipping of the lesions. We investigated the preoperative predictive value for anterior clinoidectomy in treating internal carotid-posterior communicating artery aneurysms.
We retrospectively reviewed all patients with a posterior communicating artery aneurysm treated with clipping in the past 5 years. Only the patients who underwent both computed tomographic angiography and 4-vessel digital subtraction angiography were included in this study. We measured several angles and distances on these images, and compared the parameters measured between an anterior clinoidectomy group and a non-anterior clinoidectomy group. A P value of less than 0.05 was considered significant.
We examined 94 cases of posterior communicating artery aneurysms treated with clipping. The ACP was resected in 6 of the 94 cases. In the anterior clinoidectomy group, there were 3 factors that were statistically significant. First, the calculated real distance between the ACP and the aneurysmal neck was shorter (mean, 4.4 +/- 0.7 versus 7.2 +/- 1.4 mm). Second, the angle between vertical line to cranial base and communicating segment of the internal carotid artery (ICA) was larger (mean, 62.5 +/- 4.6 versus 50.9 +/- 10.7 degrees). Third, the angle between the communicating segment and the ophthalmic segment of the ICA was smaller (mean, 66.5 +/- 15.1 versus 84.6 +/- 20.4 degrees).
The anterior clinoidectomy group showed a more tortuous course of intracranial ICA around the ACP than the nonclinoidectomy group. Therefore, measurement of the distal ICA angle is helpful in predicting the necessity of anterior clinoidectomy.
为夹闭颈内动脉-后交通动脉瘤而切除前床突（ACP）的情况很少见。然而，术前了解前床突切除术的必要性对于安全夹闭病变至关重要。我们研究了前床突切除术在治疗颈内动脉-后交通动脉瘤中的术前预测价值。
我们回顾性分析了过去5年中所有接受夹闭治疗的后交通动脉瘤患者。本研究仅纳入了同时接受计算机断层血管造影和四血管数字减影血管造影的患者。我们在这些图像上测量了几个角度和距离，并比较了前床突切除术组和非前床突切除术组之间测量的参数。P值小于0.05被认为具有统计学意义。
我们检查了94例接受夹闭治疗的后交通动脉瘤病例。94例中有6例切除了前床突。在前床突切除术组中，有3个因素具有统计学意义。首先，计算得出的前床突与瘤颈之间的实际距离较短（平均4.4±0.7对7.2±1.4毫米）。其次，与颅底垂直线和颈内动脉（ICA）交通段之间的角度较大（平均62.5±4.6对50.9±10.7度）。第三，ICA交通段与眼段之间的角度较小（平均66.5±15.1对84.6±20.4度）。
与非前床突切除术组相比，前床突切除术组颅内ICA在ACP周围的走行更曲折。因此，测量ICA远端角度有助于预测前床突切除术的必要性。
