Unruptured pericallosal artery aneurysm
Rupture risk
Compared with intracranial aneurysms (IAs) at other locations, pericallosal artery aneurysms (PAAs) have demonstrated an extremely high risk of rupture. The morphological characteristics of PAAs are unique. Compared with other anterior circulation IAs, PAAs have significantly increased aspect ratio (AR), size ratio (SR), and inflow angles, which, ultimately, promote their high propensity toward rupture 1)
Case series
A total of 12 patients with 12 unruptured pericallosal artery aneurysms, treated with coil embolization, were retrospectively investigated. Predictors for silent ischemias were evaluated by comparing diffusion-weighted imaging (DWI)-positive and DWI-negative patients.
Silent ischemic events detected on DWI were observed in eight aneurysms (66.7%). A comparison of the morphological characteristics of aneurysms between the two groups showed a significantly smaller global outflow angle (GOA) in the DWI-positive group than in the DWI-negative group (172.6 ± 17.7° vs. 216.8 ± 16.8°, P < 0.01). A multivariate analysis showed that GOA <195° was a significant predictor of silent ischemic events (P = 0.04; odds ratio: 23.62; 95% confidence interval: 1.11-490.39).
A small GOA was a significant predictor of silent ischemic events after coil embolization for unruptured DACA aneurysms. While some patients can be treated safely with minimally invasive coil embolization, it is necessary to consider surgical clipping in patients at high risk of thromboembolic events with coil embolization 2).
In a retrospective study of patients treated endovascularly for PAAs from December 2007 to January 2019. a total of 33 patients with 34 aneurysms were included (25 aneurysms ruptured, 9 unruptured or recurrent). Of the ruptured group, 22 were coiled (88%) and rest treated with flow diversion. The initial angiographic follow up rate was 72%, a median of 159 days. The overall recurrence rate was 40% (10/25) at median of 376 days, all among coiled aneurysms. 6 recurrent aneurysms retreated with further coiling (2) and flow diversion (4). Of the unruptured/recurrent group, 5 were coiled (55%) and the remainder treated with flow diversion. The angiographic follow-up rate was 100% at a median of 267 days. The recurrence rate was 22% (2/9), both in coiled aneurysms. Overall, 27 aneurysms were coiled, 9 treated with flow diversion and 3 with “partial” flow diversion. All aneurysms treated with pipeline flow diversion achieved 100% occlusion. No re-rupture or new rupture was observed. Good clinical outcome (modified Rankin Scale 0-2) was seen in 79% of patients.
This study demonstrates that endovascular coiling for PAAs is associated with a definite rate of recurrence, which has to be monitored with timely angiography. They also demonstrates the excellent effectiveness of flow diversion for PAAs with either presentation 3).
Unclassified
Last update 23.11.2019
7: Burkhardt JK, Haider AS, Rutledge WC, Wang D, Hannegan L, Lawton MT. Neurosurgical “Squeeze Play”: Single Incision with Dual Ipsilateral Craniotomies Versus 2 Separate Approaches for Intracranial Aneurysm Treatment. World Neurosurg. 2017 Nov;107:554-558. doi: 10.1016/j.wneu.2017.08.032. Epub 2017 Aug 17. PubMed PMID: 28823661.
8: Sharafeddin F, Hafez A, Lehecka M, Raj R, Colasanti R, Rafiei A, Choque J, Jahromi BR, Niemelä M, Hernesniemi J. A5 segment aneurysm of the anterior cerebral artery, imbedded into the body of the corpus callosum: A case report. Surg Neurol Int. 2017 Feb 6;8:18. doi: 10.4103/2152-7806.199559. eCollection 2017. Erratum in: Surg Neurol Int. 2017 Apr 26;8:70. PubMed PMID: 28217397; PubMed Central PMCID: PMC5309442.
9: Lee K, Park H, Park I, Park SQ, Kwon OK, Han J. Y-configuration Stent-assisted Coil Embolization for Wide-necked Intracranial Bifurcation Aneurysms. J Cerebrovasc Endovasc Neurosurg. 2016 Dec;18(4):355-362. doi: 10.7461/jcen.2016.18.4.355. Epub 2016 Dec 31. PubMed PMID: 28184345; PubMed Central PMCID: PMC5298977.
10: Korja M, Kivisaari R, Rezai Jahromi B, Lehto H. Size and location of ruptured intracranial aneurysms: consecutive series of 1993 hospital-admitted patients. J Neurosurg. 2017 Oct;127(4):748-753. doi: 10.3171/2016.9.JNS161085. Epub 2016 Dec 2. PubMed PMID: 27911237.
11: Aboukaïs R, Zairi F, Bourgeois P, Boustia F, Leclerc X, Lejeune JP. Pericallosal aneurysm: A difficult challenge for microsurgery and endovascular treatment. Neurochirurgie. 2015 Aug;61(4):244-9. doi: 10.1016/j.neuchi.2015.03.010. Epub 2015 Jun 10. PubMed PMID: 26072225.
12: Sun ZH, Wu C, Wang FY, Xue Z, Xu BN, Zhou DB. [Surgical management of intracranial mirror aneurysms]. Zhonghua Wai Ke Za Zhi. 2013 Oct;51(10):912-5. Chinese. PubMed PMID: 24433771.
13: Matsushima K, Kawashima M, Suzuyama K, Takase Y, Takao T, Matsushima T. Thrombosed giant aneurysm of the distal anterior cerebral artery treated with aneurysm resection and proximal pericallosal artery-callosomarginal artery end-to-end anastomosis: Case report and review of the literature. Surg Neurol Int. 2011;2:135. doi: 10.4103/2152-7806.85608. Epub 2011 Sep 30. PubMed PMID: 22059130; PubMed Central PMCID: PMC3205492.
14: Wang DM, Liu JC, Wang LJ, Lu J, Qi P, Zhai LL, Jiang XL. [Endovascular treatment of ruptured and unruptured intracranial very small aneurysms]. Zhonghua Yi Xue Za Zhi. 2010 Apr 20;90(15):1020-3. Chinese. PubMed PMID: 20646518.
15: Hänggi D, Winkler PA, Steiger HJ. Primary epileptogenic unruptured intracranial aneurysms: incidence and effect of treatment on epilepsy. Neurosurgery. 2010 Jun;66(6):1161-5. doi: 10.1227/01.NEU.0000369515.95351.2A. PubMed PMID: 20495430.
16: Sabatino G, Albanese A, Di Muro L, Marchese E. Bilateral intra-orbital ophthalmic artery aneurysms. Acta Neurochir (Wien). 2009 Jul;151(7):831-2. doi: 10.1007/s00701-009-0352-z. Epub 2009 May 5. PubMed PMID: 19415170.
17: Ferroli P, Ciceri E, Addis A, Broggi G. Self-closing surgical clips for use in pericallosal artery-pericallosal artery side-to-side bypass. J Neurosurg. 2008 Aug;109(2):330-4. doi: 10.3171/JNS/2008/109/8/0330. PubMed PMID: 18671649.
18: Lehecka M, Dashti R, Hernesniemi J, Niemelä M, Koivisto T, Ronkainen A, Rinne J, Jääskeläinen J. Microneurosurgical management of aneurysms at the A2 segment of anterior cerebral artery (proximal pericallosal artery) and its frontobasal branches. Surg Neurol. 2008 Sep;70(3):232-46; discussion 246. doi: 10.1016/j.surneu.2008.03.008. Epub 2008 May 16. Review. PubMed PMID: 18486199.
19: Proust F, Debono B, Hannequin D, Gerardin E, Clavier E, Langlois O, Fréger P. Treatment of anterior communicating artery aneurysms: complementary aspects of microsurgical and endovascular procedures. J Neurosurg. 2003 Jul;99(1):3-14. PubMed PMID: 12854737.
20: Schröder F, Regelsberger J, Westphal M, Freckmann N, Grzyska U, Herrmann HD. [Asymptomatic cerebral aneurysms–surgical and endovascular therapy options]. Wien Med Wochenschr. 1997;147(7-8):159-62. German. PubMed PMID: 9297364.
21: Hodozuka A, Sako K, Yonemasu Y, Suzuki N, Fujita T, Ohgami S. [Spontaneous disappearance of aneurysm after total removal of accompanying intracranial arteriovenous malformation. Case report]. Neurol Med Chir (Tokyo). 1991 Dec;31(13):966-71. Review. Japanese. PubMed PMID: 1726262.
22: Mann KS, Yue CP, Wong G. Aneurysms of the pericallosal-callosomarginal junction. Surg Neurol. 1984 Mar;21(3):261-6. PubMed PMID: 6695321.