- Email: [email protected]
Management of brain AVM procedural hemorrhagic complication by the “security” catheter technique
Journal of Neuroradiology (2013) 40, 45—49
Available online at
www.sciencedirect.com
TECHNICAL NOTE
Management of brain AVM procedural hemorrhagic complication by the ‘‘security’’ catheter technique Daniel Giansante Abud ∗, Thiago Giansante Abud , Guilherme Seizem Nakiri Division of Interventional Neuroradiology, Department of Internal Medicine, Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Avenida Bandeirantes, 3900 Monte Alegre, Brazil
KEYWORDS Brain arteriovenous malformations; Endovascular treatment; Complications
Summary Since the introduction of Onyx as a liquid embolic agent for the treatment of brain arteriovenous malformation (AVM), higher endovascular cure rates have been achieved. This may be partially attributed to its non-adhesive property, which allows longer intranidal progression of the embolic agent before solidification. However, Onyx reflux around the microcatheter can form a highly viscous plug, thereby constraining the microcatheter during its retrieval. Also, during the maneuver, arterial stretching can lead to vascular rupture and result in acute bleeding, a potentially fatal complication that demands immediate treatment. This report describes a new treatment strategy for the rapid management of such a complication. The technique consists of the placement of a second microcatheter about 2 cm proximal to the AVM nidus in the same artery containing the intranidal microcatheter. After conclusion of embolization, if rupture occurs during intranidal microcatheter retrieval, the second microcatheter that is already in place can promptly be used to control the bleeding. © 2012 Elsevier Masson SAS. All rights reserved.
Introduction The treatment of intracranial arteriovenous malformation (AVM) is still considered a complex procedure that frequently involves the association of two or even three different techniques [1], such as endovascular embolization, neurosurgery and radiosurgery. In its earlier days, the availability of permanent liquid embolic material for
Abbreviations: ACA, Anterior cerebral artery; AVM, Arteriovenous malformation; DSA, Digital subtraction angiography; MCA, Middle cerebral artery; NBCA, N-butyl-cyanoacrylate. ∗ Corresponding author. Tel.: +55 16 36 02 26 40; fax: +55 16 36 36 74 99. E-mail address: [email protected] (D.G. Abud).
endovascular AVM embolization was restricted to only adhesive embolic agents. The initial experience with these embolic agents revealed low cure rates [2], as they played only a secondary role as adjunctive therapy for surgery or radiosurgery [3,4]. However, since the introduction of Onyx (ev3, Irvine, CA, USA), a non-adhesive embolic material, higher rates of complete AVM occlusion have been obtained by endovascular embolization as the sole treatment, as shown by several studies [5,6]. Nevertheless, although Onyx has no adhesive properties, its deposition around the microcatheter can form a highviscosity plug, imprisoning the microcatheter and making its removal difficult and, in some cases, impossible without vascular tearing. The complication is directly related to the amount of Onyx reflux around the catheter, duration of the injection and tortuosity of arterial access.
0150-9861/$ – see front matter © 2012 Elsevier Masson SAS. All rights reserved. doi:10.1016/j.neurad.2012.03.010
46
D.G. Abud et al.
Rupture of the arterial pedicle during microcatheter retrieval is a serious and potentially fatal complication. The immediate treatment of this complication is mandatory, requiring prompt endovascular closure of the bleeding point. For this reason, this report describes a simple technique to optimize prompt control of the complication in selected cases where such rupture may be more prone to happen.
computed tomography (CT) scan, with no formation of acute hematoma. The three patients were extubated in the operating room, and all experienced a benign clinical course with no new deficits. All patients were discharged home on day 5 after the procedure. Angiographic control at 6 months confirmed complete circulatory exclusion of all AVMs.
Technique
Discussion
From February 2009 to November 2010, 87 AVM embolization sessions using Onyx were performed at our center. During this period, three brain AVM with compact and small niduses (< 3 cm) were selected for endovascular embolization with Onyx, targeting a curative procedure using the ‘‘security catheter’’ technique. All selected patients presented with a higher risk of hemorrhagic complication during catheter retrieval due to access tortuosity and distal locations. In two of the AVMs, the arterial supply came from distal branches of the middle cerebral artery (MCA), one of which presented with a fusiform aneurysm in the main pedicle related to the high flow redirected from the MCA. Both AVMs were located in the right frontal lobe. The third AVM was situated in the left posterior frontal lobe, and its main arterial pedicles arose from branches of the anterior cerebral artery (ACA). All procedures were standardized. A 6-F sheath was placed in each common femoral artery. After complete brain angiography, two 6-F guiding catheters (Guider Softip, Boston Scientific, Natick, MA, USA) with continuous saline perfusion were positioned in the internal carotid artery (ICA) feeding the AVM. No heparin was infused in any patient, given the risk of hemorrhagic complications. A dimethyl sulfoxide (DMSO)-compatible microcatheter was conducted through each guiding catheter (Marathon, ev3). The first microcatheter was positioned with its distal tip within the nidus, while the second catheter was placed about 2 cm proximal to the nidus in the same feeder artery. Before concluding the Onyx injection, a 50% solution of acrylic glue [N-butyl cyanoacrylate (NBCA); Hystoacryl® , B. Braun Melsungen AG, Melsungen, Germany] and lipiodol was prepared at a 1:1 dilution. As soon as embolization was completed and the microcatheter retrieved, a global angiographic control was performed. With the second microcatheter still in place, selective contrast injections could be performed to search for small bleedings not detected by global angiography. Thus, angiographic images compatible with active bleeding were identified in two patients, both with AVM embolized through an MCA branch. In one, rupture occurred in the main arterial pedicle, which was lacerated during microcatheter retrieval (Fig. 1) whereas, in the other, it arose in the high-flow fusiform aneurysm (Fig. 2). However, the two complications were readily controlled, as the second microcatheter was already in place in the arterial pedicle, ready to perform the prompt injection of glue at 50%. In the third patient, no arterial bleeding was detected, and the second microcatheter was retrieved without having been used. The two patients who presented with bleeding showed only mild subarachnoid hemorrhage (SAH) on the immediate
The use of Onyx as an embolic agent has enabled more significant cure rates for the endovascular treatment of brain AVM. As seen in some studies, the cure rates using endovascular embolization as the sole therapy range from 45% to 60% [5,6]. However, with the use of more aggressive techniques such as the one recently described by Abud et al. [7], cure rates greater than 90% may be achieved for selected AVMs. The non-adhesive characteristic of Onyx allows longer injections with gradual progression of the material before its sedimentation, leading to more homogeneous filling of the malformation nidus compared with NBCA [8]. However, despite its non-adherence, the reflux of Onyx along the microcatheter can form a highly viscous plug, which may make it difficult or even impossible to withdraw the catheter without vascular tears. In general, injections lasting up to 40 min and reflux no larger than 1.5 cm [5,9] are recommended. However, arterial pedicles that are too thin or highly tortuous can also hinder the removal of the microcatheter even in the presence of minimal Onyx reflux. Arterial rupture during removal of the microcatheter is a potentially fatal complication. Usually, the arterial tear is extensive and involves either the portion where the catheter was trapped in the reflux or in the small branches arising from the pedicle. There are several proposed techniques for withdrawing the microcatheter after Onyx injection [7], but none can definitely be said to avoid arterial rupture. In the present study, two ruptures occurred out of 87 AVM embolizations using conventional techniques. Both evolved with intracranial hematoma and required urgent surgical intervention. The rates of procedural bleeding complications related to retrieval of the microcatheter after Onyx injection are not well described in the literature, as hemorrhagic complications are usually reported without specifying the cause. The largest series [6] so far available reported no ruptures caused by retrieval of the microcatheter, although 28 catheters (in 350 patients treated) were trapped and left in place due to major reflux, thereby leading to related clinical complications. Recently, new microcatheters with detachable distal tips have become available to theoretically reduce the risk during microcatheter removal, especially when major reflux is present. However, preliminary published results [10] have shown that arterial rupture is still a hazard even with this new technology, as shown in our present study (one rupture due to retrieval of the catheter out of 76 AVM embolizations). In the presence of arterial laceration, another microcatheterization should be performed as quickly as possible, with the bleeding promptly controlled by the injection of NBCA, as they rarely stop bleeding spontaneously. Extensive
Management of brain AVM procedural hemorrhagic complication
47
Figure 1 An 11-year-old boy harbored a small ruptured right frontal arteriovenous malformation (AVM). (A) Digital subtraction angiography (DSA), lateral view, right internal carotid artery (ICA) injection, demonstrates the AVM nidus and an intranidal aneurysm fed mainly by one branch of the middle cerebral artery (MCA). (B) Plain radiography, lateral view, shows two microcatheters in place before embolization. The distal tip of the first microcatheter is positioned within the nidus (black arrow), while the second microcatheter’s distal tip is located around 2 cm proximal to the nidus in the same feeding artery (white arrow). (C) DSA selective injection through the distal microcatheter confirms its intranidal position. (D) DSA selective contrast-medium injection through the security microcatheter after withdrawal of the intranidal microcatheter demonstrates the rupture point (black arrow). (E) Plain radiography, frontal view, shows the Onyx cast (arrow) and glue in the ruptured feeder (black arrow). (F, G) DSA, right ICA, lateral (F) and frontal (G) views after embolization, demonstrates complete exclusion of the AVM, and no signs of active bleeding.
bleeding can quickly lead to severe intracranial hypertension and death. Thin and tortuous arterial access can easily rupture, even after only a small amount of reflux during a brief injection. AVMs fed by distal branches of the MCA are especially prone to rupture due to their usually tortuous anatomy. Arterial pedicles presenting with aneurysms are more prone to rupture as well. However, the risk of arterial laceration
tends to increase when curative endovascular embolization is planned, as longer injection times with greater reflux are needed to obtain complete circulatory exclusion of the AVM nidus. In our proposed technique, the placement of a second microcatheter about 2 cm proximal to the AVM nidus allows prompt access for glue injection in case rupture occurs during intranidal microcatheter retrieval. Nevertheless, it
48
D.G. Abud et al.
Figure 2 A 49-year-old woman harbored a right frontal arteriovenous malformation (AVM). (A) Digital subtraction angiography (DSA), oblique view, right internal carotid artery (ICA) injection, demonstrates the AVM nidus fed by branches of the middle cerebral artery (MCA), and multiple excluded arterial aneurysms previously treated by clipping and embolization. (B) DSA, oblique view, right ICA injection, reveals a flow arterial aneurysm located in the main feeder of the AVM (black arrow) in detail. (C) DSA selective injection through the distal microcatheter shows its intranidal position. (D) Plain radiography, lateral view, shows the two microcatheters in place before embolization, the first in an intranidal position (white arrow) and the second around 2 cm proximally (black arrow). (E) DSA selective contrast-medium injection through the security microcatheter after withdrawal of the intranidal microcatheter demonstrates the rupture point (black arrow). (F) Plain radiography, lateral view, shows the Onyx cast, the embolized glue filling the arterial feeder and the ruptured aneurysm (black arrow), and contrast in the subarachnoid space (white arrow). (G) DSA, right ICA, lateral view after embolization, demonstrates complete exclusion of the AVM and no signs of active bleeding.
is important to consider that pulling on the AVM can also lead to arterial rupture in another pedicle away from the microcatheter. This may indeed be a limitation of the ‘‘security catheter’’ technique. However, even in this rare situation, considerable time may still be saved by simply repositioning the microcatheter already in place in the intracranial circulation rather than having
to insert a new one all the way from the femoral artery. In the three selected cases reported here, complete angiographic exclusion was achieved by injection of Onyx through only one arterial access. Arterial laceration occurred after microcatheter retrieval in two cases. In both of them, the bleeding was quickly controlled by injection
Management of brain AVM procedural hemorrhagic complication of NBCA at 50% through the ‘‘security catheter’’ already in place. In our opinion, this technique is simple to apply and useful for those cases that are more likely to present with rupture and bleeding during microcatheter withdrawal, such as embolizations with curative intent, where longer injection times and larger amounts of reflux may be needed to achieve complete filling of the AVM nidus.
Disclosure of interest The authors declare that they have no conflicts of interest concerning this article.
References [1] Richling B, Killer M, Al-Schameri AR, et al. Therapy of brain arteriovenous malformations: multimodality treatment from a balanced standpoint. Neurosurgery 2006;59:S148—57. [2] n-BCA Trail Investigators. N-butyl cyanoacrylate embolization of cerebral arteriovenous malformations: results of a prospective, randomized, multi-center trial. AJNR Am J Neuroradiol 2002;23:748—55. [3] Pelz DM, Fox AJ, Vi˜ nuela F, et al. Preoperative embolization of brain AVMs with isobutyl-2 cyanoacrylate. AJNR Am J Neuroradiol 1988;9:757—64.
49
[4] Mamalui-Hunter M, Jiang T, Rich KM, et al. Effect of liquid embolic agents on Gamma Knife surgery dosimetry for arteriovenous malformations. Clinical article. J Neurosurg 2011;115:364—70. [5] Mounayer C, Hammami N, Piotin M, et al. Nidal embolization of brain arteriovenous malformations using Onyx in 94 patients. AJNR Am J Neuroradiol 2007;28:518—23. [6] Saatci I, Geyik S, Yavuz K, et al. Endovascular treatment of brain arteriovenous malformations with prolonged intranidal Onyx injection technique: long-term results in 350 consecutive patients with completed endovascular treatment course. J Neurosurg 2011;115:78—88. [7] Abud DG, Riva R, Nakiri GS, et al. Treatment of brain arteriovenous malformations by double arterial catheterization with simultaneous injection of Onyx: retrospective series of 17 patients. AJNR Am J Neuroradiol 2011;32:152—8. [8] Loh Y, Duckwiler GR, Onyx Trial Investigators. A prospective, multicenter, randomized trial of the Onyx liquid embolic system and N-butyl cyanoacrylate embolization of cerebral arteriovenous malformations. Clinical article. J Neurosurg 2010;113:733—41. [9] Weber W, Kis B, Siekmann R, et al. Endovascular treatment of intracranial arteriovenous malformations with Onyx: technical aspects. AJNR Am J Neuroradiol 2007;28:371—7. [10] Maimon S, Strauss I, Frolov V, et al. Brain arteriovenous malformation treatment using a combination of Onyx and a new detachable tip microcatheter, SONIC: short-term results. AJNR Am J Neuroradiol 2010;31:947—54.
Available online at
www.sciencedirect.com
TECHNICAL NOTE
Management of brain AVM procedural hemorrhagic complication by the ‘‘security’’ catheter technique Daniel Giansante Abud ∗, Thiago Giansante Abud , Guilherme Seizem Nakiri Division of Interventional Neuroradiology, Department of Internal Medicine, Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Avenida Bandeirantes, 3900 Monte Alegre, Brazil
KEYWORDS Brain arteriovenous malformations; Endovascular treatment; Complications
Summary Since the introduction of Onyx as a liquid embolic agent for the treatment of brain arteriovenous malformation (AVM), higher endovascular cure rates have been achieved. This may be partially attributed to its non-adhesive property, which allows longer intranidal progression of the embolic agent before solidification. However, Onyx reflux around the microcatheter can form a highly viscous plug, thereby constraining the microcatheter during its retrieval. Also, during the maneuver, arterial stretching can lead to vascular rupture and result in acute bleeding, a potentially fatal complication that demands immediate treatment. This report describes a new treatment strategy for the rapid management of such a complication. The technique consists of the placement of a second microcatheter about 2 cm proximal to the AVM nidus in the same artery containing the intranidal microcatheter. After conclusion of embolization, if rupture occurs during intranidal microcatheter retrieval, the second microcatheter that is already in place can promptly be used to control the bleeding. © 2012 Elsevier Masson SAS. All rights reserved.
Introduction The treatment of intracranial arteriovenous malformation (AVM) is still considered a complex procedure that frequently involves the association of two or even three different techniques [1], such as endovascular embolization, neurosurgery and radiosurgery. In its earlier days, the availability of permanent liquid embolic material for
Abbreviations: ACA, Anterior cerebral artery; AVM, Arteriovenous malformation; DSA, Digital subtraction angiography; MCA, Middle cerebral artery; NBCA, N-butyl-cyanoacrylate. ∗ Corresponding author. Tel.: +55 16 36 02 26 40; fax: +55 16 36 36 74 99. E-mail address: [email protected] (D.G. Abud).
endovascular AVM embolization was restricted to only adhesive embolic agents. The initial experience with these embolic agents revealed low cure rates [2], as they played only a secondary role as adjunctive therapy for surgery or radiosurgery [3,4]. However, since the introduction of Onyx (ev3, Irvine, CA, USA), a non-adhesive embolic material, higher rates of complete AVM occlusion have been obtained by endovascular embolization as the sole treatment, as shown by several studies [5,6]. Nevertheless, although Onyx has no adhesive properties, its deposition around the microcatheter can form a highviscosity plug, imprisoning the microcatheter and making its removal difficult and, in some cases, impossible without vascular tearing. The complication is directly related to the amount of Onyx reflux around the catheter, duration of the injection and tortuosity of arterial access.
0150-9861/$ – see front matter © 2012 Elsevier Masson SAS. All rights reserved. doi:10.1016/j.neurad.2012.03.010
46
D.G. Abud et al.
Rupture of the arterial pedicle during microcatheter retrieval is a serious and potentially fatal complication. The immediate treatment of this complication is mandatory, requiring prompt endovascular closure of the bleeding point. For this reason, this report describes a simple technique to optimize prompt control of the complication in selected cases where such rupture may be more prone to happen.
computed tomography (CT) scan, with no formation of acute hematoma. The three patients were extubated in the operating room, and all experienced a benign clinical course with no new deficits. All patients were discharged home on day 5 after the procedure. Angiographic control at 6 months confirmed complete circulatory exclusion of all AVMs.
Technique
Discussion
From February 2009 to November 2010, 87 AVM embolization sessions using Onyx were performed at our center. During this period, three brain AVM with compact and small niduses (< 3 cm) were selected for endovascular embolization with Onyx, targeting a curative procedure using the ‘‘security catheter’’ technique. All selected patients presented with a higher risk of hemorrhagic complication during catheter retrieval due to access tortuosity and distal locations. In two of the AVMs, the arterial supply came from distal branches of the middle cerebral artery (MCA), one of which presented with a fusiform aneurysm in the main pedicle related to the high flow redirected from the MCA. Both AVMs were located in the right frontal lobe. The third AVM was situated in the left posterior frontal lobe, and its main arterial pedicles arose from branches of the anterior cerebral artery (ACA). All procedures were standardized. A 6-F sheath was placed in each common femoral artery. After complete brain angiography, two 6-F guiding catheters (Guider Softip, Boston Scientific, Natick, MA, USA) with continuous saline perfusion were positioned in the internal carotid artery (ICA) feeding the AVM. No heparin was infused in any patient, given the risk of hemorrhagic complications. A dimethyl sulfoxide (DMSO)-compatible microcatheter was conducted through each guiding catheter (Marathon, ev3). The first microcatheter was positioned with its distal tip within the nidus, while the second catheter was placed about 2 cm proximal to the nidus in the same feeder artery. Before concluding the Onyx injection, a 50% solution of acrylic glue [N-butyl cyanoacrylate (NBCA); Hystoacryl® , B. Braun Melsungen AG, Melsungen, Germany] and lipiodol was prepared at a 1:1 dilution. As soon as embolization was completed and the microcatheter retrieved, a global angiographic control was performed. With the second microcatheter still in place, selective contrast injections could be performed to search for small bleedings not detected by global angiography. Thus, angiographic images compatible with active bleeding were identified in two patients, both with AVM embolized through an MCA branch. In one, rupture occurred in the main arterial pedicle, which was lacerated during microcatheter retrieval (Fig. 1) whereas, in the other, it arose in the high-flow fusiform aneurysm (Fig. 2). However, the two complications were readily controlled, as the second microcatheter was already in place in the arterial pedicle, ready to perform the prompt injection of glue at 50%. In the third patient, no arterial bleeding was detected, and the second microcatheter was retrieved without having been used. The two patients who presented with bleeding showed only mild subarachnoid hemorrhage (SAH) on the immediate
The use of Onyx as an embolic agent has enabled more significant cure rates for the endovascular treatment of brain AVM. As seen in some studies, the cure rates using endovascular embolization as the sole therapy range from 45% to 60% [5,6]. However, with the use of more aggressive techniques such as the one recently described by Abud et al. [7], cure rates greater than 90% may be achieved for selected AVMs. The non-adhesive characteristic of Onyx allows longer injections with gradual progression of the material before its sedimentation, leading to more homogeneous filling of the malformation nidus compared with NBCA [8]. However, despite its non-adherence, the reflux of Onyx along the microcatheter can form a highly viscous plug, which may make it difficult or even impossible to withdraw the catheter without vascular tears. In general, injections lasting up to 40 min and reflux no larger than 1.5 cm [5,9] are recommended. However, arterial pedicles that are too thin or highly tortuous can also hinder the removal of the microcatheter even in the presence of minimal Onyx reflux. Arterial rupture during removal of the microcatheter is a potentially fatal complication. Usually, the arterial tear is extensive and involves either the portion where the catheter was trapped in the reflux or in the small branches arising from the pedicle. There are several proposed techniques for withdrawing the microcatheter after Onyx injection [7], but none can definitely be said to avoid arterial rupture. In the present study, two ruptures occurred out of 87 AVM embolizations using conventional techniques. Both evolved with intracranial hematoma and required urgent surgical intervention. The rates of procedural bleeding complications related to retrieval of the microcatheter after Onyx injection are not well described in the literature, as hemorrhagic complications are usually reported without specifying the cause. The largest series [6] so far available reported no ruptures caused by retrieval of the microcatheter, although 28 catheters (in 350 patients treated) were trapped and left in place due to major reflux, thereby leading to related clinical complications. Recently, new microcatheters with detachable distal tips have become available to theoretically reduce the risk during microcatheter removal, especially when major reflux is present. However, preliminary published results [10] have shown that arterial rupture is still a hazard even with this new technology, as shown in our present study (one rupture due to retrieval of the catheter out of 76 AVM embolizations). In the presence of arterial laceration, another microcatheterization should be performed as quickly as possible, with the bleeding promptly controlled by the injection of NBCA, as they rarely stop bleeding spontaneously. Extensive
Management of brain AVM procedural hemorrhagic complication
47
Figure 1 An 11-year-old boy harbored a small ruptured right frontal arteriovenous malformation (AVM). (A) Digital subtraction angiography (DSA), lateral view, right internal carotid artery (ICA) injection, demonstrates the AVM nidus and an intranidal aneurysm fed mainly by one branch of the middle cerebral artery (MCA). (B) Plain radiography, lateral view, shows two microcatheters in place before embolization. The distal tip of the first microcatheter is positioned within the nidus (black arrow), while the second microcatheter’s distal tip is located around 2 cm proximal to the nidus in the same feeding artery (white arrow). (C) DSA selective injection through the distal microcatheter confirms its intranidal position. (D) DSA selective contrast-medium injection through the security microcatheter after withdrawal of the intranidal microcatheter demonstrates the rupture point (black arrow). (E) Plain radiography, frontal view, shows the Onyx cast (arrow) and glue in the ruptured feeder (black arrow). (F, G) DSA, right ICA, lateral (F) and frontal (G) views after embolization, demonstrates complete exclusion of the AVM, and no signs of active bleeding.
bleeding can quickly lead to severe intracranial hypertension and death. Thin and tortuous arterial access can easily rupture, even after only a small amount of reflux during a brief injection. AVMs fed by distal branches of the MCA are especially prone to rupture due to their usually tortuous anatomy. Arterial pedicles presenting with aneurysms are more prone to rupture as well. However, the risk of arterial laceration
tends to increase when curative endovascular embolization is planned, as longer injection times with greater reflux are needed to obtain complete circulatory exclusion of the AVM nidus. In our proposed technique, the placement of a second microcatheter about 2 cm proximal to the AVM nidus allows prompt access for glue injection in case rupture occurs during intranidal microcatheter retrieval. Nevertheless, it
48
D.G. Abud et al.
Figure 2 A 49-year-old woman harbored a right frontal arteriovenous malformation (AVM). (A) Digital subtraction angiography (DSA), oblique view, right internal carotid artery (ICA) injection, demonstrates the AVM nidus fed by branches of the middle cerebral artery (MCA), and multiple excluded arterial aneurysms previously treated by clipping and embolization. (B) DSA, oblique view, right ICA injection, reveals a flow arterial aneurysm located in the main feeder of the AVM (black arrow) in detail. (C) DSA selective injection through the distal microcatheter shows its intranidal position. (D) Plain radiography, lateral view, shows the two microcatheters in place before embolization, the first in an intranidal position (white arrow) and the second around 2 cm proximally (black arrow). (E) DSA selective contrast-medium injection through the security microcatheter after withdrawal of the intranidal microcatheter demonstrates the rupture point (black arrow). (F) Plain radiography, lateral view, shows the Onyx cast, the embolized glue filling the arterial feeder and the ruptured aneurysm (black arrow), and contrast in the subarachnoid space (white arrow). (G) DSA, right ICA, lateral view after embolization, demonstrates complete exclusion of the AVM and no signs of active bleeding.
is important to consider that pulling on the AVM can also lead to arterial rupture in another pedicle away from the microcatheter. This may indeed be a limitation of the ‘‘security catheter’’ technique. However, even in this rare situation, considerable time may still be saved by simply repositioning the microcatheter already in place in the intracranial circulation rather than having
to insert a new one all the way from the femoral artery. In the three selected cases reported here, complete angiographic exclusion was achieved by injection of Onyx through only one arterial access. Arterial laceration occurred after microcatheter retrieval in two cases. In both of them, the bleeding was quickly controlled by injection
Management of brain AVM procedural hemorrhagic complication of NBCA at 50% through the ‘‘security catheter’’ already in place. In our opinion, this technique is simple to apply and useful for those cases that are more likely to present with rupture and bleeding during microcatheter withdrawal, such as embolizations with curative intent, where longer injection times and larger amounts of reflux may be needed to achieve complete filling of the AVM nidus.
Disclosure of interest The authors declare that they have no conflicts of interest concerning this article.
References [1] Richling B, Killer M, Al-Schameri AR, et al. Therapy of brain arteriovenous malformations: multimodality treatment from a balanced standpoint. Neurosurgery 2006;59:S148—57. [2] n-BCA Trail Investigators. N-butyl cyanoacrylate embolization of cerebral arteriovenous malformations: results of a prospective, randomized, multi-center trial. AJNR Am J Neuroradiol 2002;23:748—55. [3] Pelz DM, Fox AJ, Vi˜ nuela F, et al. Preoperative embolization of brain AVMs with isobutyl-2 cyanoacrylate. AJNR Am J Neuroradiol 1988;9:757—64.
49
[4] Mamalui-Hunter M, Jiang T, Rich KM, et al. Effect of liquid embolic agents on Gamma Knife surgery dosimetry for arteriovenous malformations. Clinical article. J Neurosurg 2011;115:364—70. [5] Mounayer C, Hammami N, Piotin M, et al. Nidal embolization of brain arteriovenous malformations using Onyx in 94 patients. AJNR Am J Neuroradiol 2007;28:518—23. [6] Saatci I, Geyik S, Yavuz K, et al. Endovascular treatment of brain arteriovenous malformations with prolonged intranidal Onyx injection technique: long-term results in 350 consecutive patients with completed endovascular treatment course. J Neurosurg 2011;115:78—88. [7] Abud DG, Riva R, Nakiri GS, et al. Treatment of brain arteriovenous malformations by double arterial catheterization with simultaneous injection of Onyx: retrospective series of 17 patients. AJNR Am J Neuroradiol 2011;32:152—8. [8] Loh Y, Duckwiler GR, Onyx Trial Investigators. A prospective, multicenter, randomized trial of the Onyx liquid embolic system and N-butyl cyanoacrylate embolization of cerebral arteriovenous malformations. Clinical article. J Neurosurg 2010;113:733—41. [9] Weber W, Kis B, Siekmann R, et al. Endovascular treatment of intracranial arteriovenous malformations with Onyx: technical aspects. AJNR Am J Neuroradiol 2007;28:371—7. [10] Maimon S, Strauss I, Frolov V, et al. Brain arteriovenous malformation treatment using a combination of Onyx and a new detachable tip microcatheter, SONIC: short-term results. AJNR Am J Neuroradiol 2010;31:947—54.