Ujiie H, Tamano Y, Sasaki K, Hori T
Department of Neurosurgery, Neurological Institute, Tokyo Women's Medical University, Japan.
Neurosurgery. 2001 Mar;48(3):495-502; discussion 502-3. doi: 10.1097/00006123-200103000-00007.
The present retrospective study was undertaken to prove the reliability of the aspect ratio (aneurysm depth to aneurysm neck width) for predicting an aneurysmal rupture. The aspect ratio is considered a better geometric index than aneurysm size for determining the intra-aneurysmal blood flow.
We measured the aspect ratios and the sizes of aneurysms, as determined by examining angiographic films magnified 1.4x, in 129 patients with ruptured aneurysms and in 72 patients with 78 unruptured aneurysms. After categorizing the aneurysms into four groups on the basis of their locations (aneurysms of the anterior communicating artery, middle cerebral artery, internal carotid artery-posterior communicating artery [ICA-PComA], and other aneurysms), a statistical analysis of ruptured and unruptured aneurysms was performed.
The mean aneurysm size was found to be statistically significant in the aneurysms at the ICA-PComA and in locations excluding the anterior communicating artery, the middle cerebral artery, and the ICA-PComA. However, the mean aspect ratio was statistically significant at all four locations. In patients with ruptured aneurysms, no ruptured aneurysms with an aspect ratio of less than 1.0 were found. The distribution of the ruptured group versus the unruptured group with an aspect ratio of less than 1.6 at each location was 13 versus 79%, respectively, at the anterior communicating artery, 11 versus 58% at the middle cerebral artery, 11% versus 85% at the ICA-PComA, and 7 versus 81% at other locations.
The aspect ratio between ruptured aneurysms and unruptured aneurysms was found to be statistically significant, and almost 80% of the ruptured aneurysms showed an aspect ratio of more than 1.6, whereas almost 90% of the unruptured aneurysms showed an aspect ratio of less than 1.6. This study therefore suggests that the aspect ratio may be useful in predicting imminent aneurysmal ruptures.
进行本回顾性研究以证明纵横比（动脉瘤深度与动脉瘤颈部宽度之比）在预测动脉瘤破裂方面的可靠性。在确定动脉瘤内血流情况时，纵横比被认为是比动脉瘤大小更好的几何指标。
我们在129例破裂动脉瘤患者和72例患有78个未破裂动脉瘤的患者中，通过检查放大1.4倍的血管造影胶片来测量动脉瘤的纵横比和大小。在根据动脉瘤位置（前交通动脉、大脑中动脉、颈内动脉-后交通动脉[ICA-PComA]和其他动脉瘤）将动脉瘤分为四组后，对破裂和未破裂的动脉瘤进行了统计分析。
发现ICA-PComA处以及排除前交通动脉、大脑中动脉和ICA-PComA的部位的动脉瘤，其平均动脉瘤大小具有统计学意义。然而，在所有四个部位，平均纵横比均具有统计学意义。在破裂动脉瘤患者中，未发现纵横比小于1.0的破裂动脉瘤。在每个部位，纵横比小于1.6的破裂组与未破裂组的分布情况分别为：前交通动脉处为13%对79%，大脑中动脉处为11%对58%，ICA-PComA处为11%对85%，其他部位为7%对81%。
发现破裂动脉瘤与未破裂动脉瘤之间的纵横比具有统计学意义，几乎80%的破裂动脉瘤纵横比大于1.6，而几乎90%的未破裂动脉瘤纵横比小于1.6。因此，本研究表明纵横比可能有助于预测即将发生的动脉瘤破裂。
