Use of the Apollo detachable-tip microcatheter for endovascular embolization of arteriovenous malformations and arteriovenous fistulas

Restricted access


Liquid embolic agents have revolutionized endovascular management of arteriovenous malformations (AVMs) and arteriovenous fistulas (AVFs). Nonetheless, since 2005, the US FDA has received more than 100 reports of microcatheter breakage or entrapment related to Onyx embolization, including 9 deaths. In 2014, the Apollo detachable-tip microcatheter became the first of its kind available in the US. Since then, few reports on its safety have been published.


The authors conducted a retrospective review of endovascular cases by searching the patient databases at 2 tertiary cerebrovascular centers (Barrow Neurological Institute and University of Pittsburgh Medical Center). Patients who underwent endovascular embolization of an AVM or AVF using the Apollo microcatheter were identified. Patient demographics and lesion characteristics were collected. The authors analyzed Apollo-specific endovascular variables, such as number of microcatheterizations, sessions, and pedicles embolized; microcatheter tip detachment status; obliteration rate; and endovascular- and microcatheter-related morbidity and mortality.


From July 2014 to October 2016, a total of 177 embolizations using the Apollo microcatheter were performed in 61 patients (mean age 40.3 years). The most frequent presentation was hemorrhage (22/61, 36.1%). Most lesions were AVMs (51/61, 83.6%; mean diameter 30.6 mm). The mean Spetzler-Martin grade was 2.4. Thirty-nine (76.5%) of 51 patients with AVMs underwent resection. Microcatheterization was successful in 172 pedicles. Most patients (50/61, 82%) underwent a single embolization session. The mean number of pedicles per session was 2.5 (range 1–7). Onyx-18 was used in 103 (59.9%), N-butyl cyanoacrylate (NBCA) in 44 (25.6%), and Onyx-34 in 25 (14.5%) of the 172 embolizations. In 45.9% (28/61) of the patients, lesion obliteration of 75% or greater was achieved. Tip detachment occurred in 19.2% (33/172) of microcatheters. Fifty-three (86.9%) of the 61 patients who underwent embolization with the Apollo microcatheter had good functional outcomes (modified Rankin Scale score 0–2). No unintended microcatheter fractures or related morbidity was observed. One patient died of intraprocedural complications unrelated to microcatheter selection. In the univariate analysis, microcatheter tip detachment (p = 0.12), single embolized pedicles (p = 0.12), and smaller AVM nidus diameter (p = 0.17) correlated positively with high obliteration rates (> 90%). In the multivariate analysis, microcatheter tip detachment was the only independent variable associated with high obliteration rates (OR 9.5; p = 0.03).


The use of the Apollo detachable-tip microcatheter for embolization of AVMs and AVFs is associated with high rates of successful catheterization and obliteration and low rates of morbidity and mortality. The microcatheter was retrieved in all cases, even after prolonged injections in distal branch pedicles, often with significant reflux. This study represents the largest case series on the application of the Apollo microcatheter for neurointerventional procedures.

ABBREVIATIONS AVF = arteriovenous fistula; AVM = arteriovenous malformation; DMSO = dimethyl sulfoxide; EVOH = ethylene vinyl alcohol; NBCA = N-butyl cyanoacrylate.

Article Information

Correspondence Felipe C. Albuquerque: c/o Neuroscience Publications, Barrow Neurological Institute, St. Joseph’s Hospital and Medical Center, Phoenix, AZ.

INCLUDE WHEN CITING Published online March 23, 2018; DOI: 10.3171/2017.9.JNS17397.

Disclosures Dr. Ducruet: consultant for Medtronic.

© AANS, except where prohibited by US copyright law.



  • View in gallery

    Left: Intact Apollo microcatheter with 2 distinct components: the primary catheter and the detachable tip. The orange segment contains a radiopaque proximal marker within it, and the gray detachable segment contains a second distal radiopaque marker at the tip. The separation point is approximately midway along the orange segment and is immediately distal to the radiopaque marker. Right: Apollo microcatheter showing a detached tip. Figure is available in color online only.

  • View in gallery

    A: Anteroposterior (AP) right internal carotid artery (ICA) subtracted angiogram of a Spetzler-Martin grade IV unruptured AVM in the right frontal region in a patient who presented with seizures refractory to medical therapy. This image demonstrates an arterial supply from the right pericallosal artery, the right callosomarginal artery, the right parietal cortical middle cerebral artery branches, and a lateral lenticulostriate artery. B: A large Onyx embolysate cast is visible in this AP native fluoroscopic image. An occipital neuromonitoring lead is visible at the medial aspect of the Onyx cast, and an Apollo microcatheter is visible in the inferomedial corner within an intermediate catheter (note the 2 radiopaque markers defining the Apollo detachment zone and the Apollo distal tip). A previously detached Apollo tip is visible on the inferior aspect of the Onyx cast (arrows). C: Final postembolization AP right ICA subtracted angiogram demonstrating 60% angiographic obliteration. This patient underwent 4 endovascular sessions, with 14 embolized pedicles (13 using Apollo microcatheters); NBCA, Onyx-18, and Onyx-34 were used as liquid embolysates. D: Postoperative follow-up AP right ICA subtracted angiogram demonstrating complete resection.

  • View in gallery

    Left: A Spetzler-Martin grade II AVM in the right cerebellar hemisphere in a patient who presented with hemorrhage. The arterial supply to the AVM was primarily through the right anterior inferior cerebellar artery and the right superior cerebellar artery. The AVM was preoperatively embolized using an Apollo microcatheter and Onyx-18 through a single pedicle off the right anterior inferior cerebellar artery. Right: Postembolization oblique subtracted angiogram revealing complete angiographic obliteration. Note the subtracted image of the detached microcatheter distal tip (arrow).



Abud DGde Castro-Afonso LHNakiri GSMonsignore LMColli BO: Modified pressure cooker technique: an easier way to control Onyx reflux. J Neuroradiol 43:2182222016


Altschul DParamasivam SOrtega-Gutierrez SFifi JTBerenstein A: Safety and efficacy using a detachable tip microcatheter in the embolization of pediatric arteriovenous malformations. Childs Nerv Syst 30:109911072014


Baharvahdat HBlanc RTermechi RPistocchi SBartolini BRedjem H: Hemorrhagic complications after endovascular treatment of cerebral arteriovenous malformations. AJNR Am J Neuroradiol 35:9789832014


Chapot RStracke PVelasco ANordmeyer HHeddier MStauder M: The pressure cooker technique for the treatment of brain AVMs. J Neuroradiol 41:87912014


Crowley RWDucruet AFKalani MYKim LJAlbuquerque FCMcDougall CG: Neurological morbidity and mortality associated with the endovascular treatment of cerebral arteriovenous malformations before and during the Onyx era. J Neurosurg 122:149214972015


de Castro-Afonso LHNakiri GSOliveira RSSantos MVSantos ACDMachado HR: Curative embolization of pediatric intracranial arteriovenous malformations using Onyx: the role of new embolization techniques on patient outcomes. Neuroradiology 58:5855942016


Farrell BGodwin JRichards SWarlow C: The United Kingdom transient ischaemic attack (UK-TIA) aspirin trial: final results. J Neurol Neurosurg Psychiatry 54:104410541991


Flores BCGross BAAlbuquerque FC: Endovascular treatment of arteriovenous malformations using ethylene vinyl alcohol copolymer in Prestigiacomo CJGandhi CD (eds): Cerebrovascular and Endovascular Neurosurgery. New York: Springer2018


Flores BCKlinger DRRickert KLBarnett SLWelch BGWhite JA: Management of intracranial aneurysms associated with arteriovenous malformations. Neurosurg Focus 37(3):E112014


Gao KYang XJMu SQLi YXZhang YP M: Embolization of brain arteriovenous malformations with ethylene vinyl alcohol copolymer: technical aspects. Chin Med J (Engl) 122:185118562009


Hauck EFWelch BGWhite JAPurdy PDPride LGSamson D: Preoperative embolization of cerebral arteriovenous malformations with Onyx. AJNR Am J Neuroradiol 30:4924952009


Herial NAKhan AASherr GTQureshi MHSuri MFQureshi AI: Detachable-tip microcatheters for liquid embolization of brain arteriovenous malformations and fistulas: a United States single-center experience. Neurosurgery 11 (Suppl 3):4044112015


Herial NAKhan AASuri MFSherr GTQureshi AI: Liquid embolization of brain arteriovenous malformation using novel detachable tip micro catheter: a technical report. J Vasc Interv Neurol 7:64682014


Katsaridis VPapagiannaki CAimar E: Curative embolization of cerebral arteriovenous malformations (AVMs) with Onyx in 101 patients. Neuroradiology 50:5895972008


Limbucci NSpinelli GNappini SRenieri LConsoli ARosi A: Curative transvenous Onyx embolization of a maxillary arteriovenous malformation in a child: report of a new technique. J Craniofac Surg 27:e217e2192016


Lin NSmith ERScott RMOrbach DB: Safety of neuroangiography and embolization in children: complication analysis of 697 consecutive procedures in 394 patients. J Neurosurg Pediatr 16:4324382015


Loh YDuckwiler GR: A prospective, multicenter, randomized trial of the Onyx liquid embolic system and N-butyl cyanoacrylate embolization of cerebral arteriovenous malformations. Clinical article. J Neurosurg 113:7337412010


Lopes DKMoftakhar RStraus DMunich SAChaus FKaszuba MC: Arteriovenous malformation embocure score: AVMES. J Neurointerv Surg 8:6856912016


Lv XWu ZJiang CLi YYang XZhang Y: Complication risk of endovascular embolization for cerebral arteriovenous malformation. Eur J Radiol 80:7767792011


Maimon SStrauss IFrolov VMargalit NRam Z: Brain arteriovenous malformation treatment using a combination of Onyx and a new detachable tip microcatheter, SONIC: short-term results. AJNR Am J Neuroradiol 31:9479542010


Mounayer CHammami NPiotin MSpelle LBenndorf GKessler I: Nidal embolization of brain arteriovenous malformations using Onyx in 94 patients. AJNR Am J Neuroradiol 28:5185232007


Öztürk MHÜnal HDinç H: Embolization of an AVM with acrylic glue through a new microcatheter with detachable tip: an amazing experience. Neuroradiology 50:9039042008


Panagiotopoulos VGizewski EAsgari SRegel JForsting MWanke I: Embolization of intracranial arteriovenous malformations with ethylene-vinyl alcohol copolymer (Onyx). AJNR Am J Neuroradiol 30:991062009


Paramasivam SAltschul DOrtega-Gutiarrez SFifi JBerenstein A: N-butyl cyanoacrylate embolization using a detachable tip microcatheter: initial experience. J Neurointerv Surg 7:4584612015


Pérez-Higueras ALópez RRTapia DQ: Endovascular treatment of cerebral AVM: our experience with Onyx. Interv Neuroradiol 11 (Suppl 1):1411572005


Pierot LCognard CHerbreteau DFransen Hvan Rooij WJBoccardi E: Endovascular treatment of brain arteriovenous malformations using a liquid embolic agent: results of a prospective, multicentre study (BRAVO). Eur Radiol 23:283828452013


Pierot LJanuel ACHerbreteau DBarreau XDrouineau JBerge J: Endovascular treatment of brain arteriovenous malformations using Onyx: preliminary results of a prospective multicenter study. Interv Neuroradiol 11 (Suppl 1):1591642005


Pierot LJanuel ACHerbreteau DBarreau XDrouineau JBerge J: Endovascular treatment of brain arteriovenous malformations using Onyx: results of a prospective, multicenter study. J Neuroradiol 36:1471522009


Renieri LConsoli AScarpini GGrazzini GNappini SMangiafico S: Double arterial catheterization technique for embolization of brain arteriovenous malformations with Onyx. Neurosurgery 72:92982013


Saatci IGeyik SYavuz KCekirge HS: 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 115:78882011


Singla AFargen KMHoh B: Onyx extrusion through the scalp after embolization of dural arteriovenous fistula. J Neurointerv Surg 8:e382016


Song DLeng BGu YZhu WXu BChen X: Clinical analysis of 50 cases of BAVM embolization with Onyx, a novel liquid embolic agent. Interv Neuroradiol 11 (Suppl 1):1791842005


Strauss IFrolov VBuchbut DGonen LMaimon S: Critical appraisal of endovascular treatment of brain arteriovenous malformation using Onyx in a series of 92 consecutive patients. Acta Neurochir (Wien) 155:6116172013


Tahon FSalkine FAmsalem YAguettaz PLamy BTurjman F: Dural arteriovenous fistula of the anterior fossa treated with the Onyx liquid embolic system and the Sonic microcatheter. Neuroradiology 50:4294322008


US Food and Drug Administration. Catheter Entrapment with the ev3 Onyx Liquid Embolic System: FDA Safety Communication. ( [Accessed November 16 2017]


van Rooij WJJacobs SSluzewski Mvan der Pol BBeute GNSprengers ME: Curative embolization of brain arteriovenous malformations with Onyx: patient selection, embolization technique, and results. AJNR Am J Neuroradiol 33:129913042012


van Rooij WJSluzewski MBeute GN: Brain AVM embolization with Onyx. AJNR Am J Neuroradiol 28:1721782007


Weber WKis BSiekmann RJans PLaumer RKühne D: Preoperative embolization of intracranial arteriovenous malformations with Onyx. Neurosurgery 61:2442542007


Weber WKis BSiekmann RKuehne D: Endovascular treatment of intracranial arteriovenous malformations with Onyx: technical aspects. AJNR Am J Neuroradiol 28:3713772007


Xu FNi WLiao YGu YXu BLeng B: Onyx embolization for the treatment of brain arteriovenous malformations. Acta Neurochir (Wien) 153:8698782011




All Time Past Year Past 30 Days
Abstract Views 101 101 101
Full Text Views 51 51 51
PDF Downloads 32 32 32
EPUB Downloads 0 0 0


Google Scholar