- Division of Neurological Surgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
Division of Neurological Surgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
DOI:10.4103/2152-7806.145927Copyright: © 2014 Uschold T. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
How to cite this article: Uschold T, Abla AA, Wilson DA, McDougall CG, Nakaji P. Intradural vertebral endarterectomy with nonautologous patch angioplasty for refractory vertebrobasilar ischemia: Case report and literature review. Surg Neurol Int 29-Nov-2014;5:166
How to cite this URL: Uschold T, Abla AA, Wilson DA, McDougall CG, Nakaji P. Intradural vertebral endarterectomy with nonautologous patch angioplasty for refractory vertebrobasilar ischemia: Case report and literature review. Surg Neurol Int 29-Nov-2014;5:166. Available from: http://sni.wpengine.com/surgicalint_articles/intradural-vertebral-endarterectomy-with-nonautologous-patch-angioplasty-for-refractory-vertebrobasilar-ischemia-case-report-and-literature-review/
Background:The natural history of patients with symptomatic vertebrobasilar ischemic symptoms due to chronic bilateral vertebral artery occlusive disease is progressive, and poses significant challenges when refractory to medical therapy. Surgical treatment options depend largely on location and characteristics of the atheroma (s), and generally include percutaneous transluminal angioplasty (PTA) with or without stent placement, posterior circulation revascularization (bypass), extracranial vertebral artery reconstruction, or vertebral artery endarterectomy.
Case Description:We present the case of a 56-year-old male with progressive vertebrobasilar ischemia due to tandem lesions in the right vertebral artery at the origin and intracranially in the V4 segment. The contralateral vertebral artery was occluded to the level of posterior inferior cerebellar artery (PICA) and posterior communicating arteries were absent. Following PTA and stent placement at the right vertebral artery origin, the patient was successfully treated with intradural vertebral artery endarterectomy (V4EA) and patch angioplasty via the far lateral approach. Distal endovascular intervention at the V4 segment proved not technically feasible after multiple attempts.
Conclusions:V4EA is an uncommonly performed procedure, but may be considered for carefully selected patients. The authors’ techniques and indications are discussed. Historical outcomes, relevant anatomic considerations, and lessons learned are reviewed from the literature.
Keywords: Endarterectomy, patch angioplasty, vertebral stenosis, vertebrobasilar ischemia
Symptomatic intracranial vertebral artery (VA; V4 segment) thrombo-occlusive disease, its natural history, and associated treatment strategies have not been as rigorously studied in comparison to stroke phenomena originating from the internal carotid artery.[
Surgical interventions for patient's refractory to medical therapy consist principally of open arterial bypass, or percutaneous transluminal angioplasty (PTA) and stent placement. Posterior fossa bypass procedures are technically demanding with significant risk of morbidity, particularly in the setting of graft occlusion.[
Intradural vertebral (V4 segment) endarterectomy (V4EA) is an uncommonly performed revascularization alternative. Despite inherent advantages, the applicability of V4EA is limited due to narrow indications for a highly selected population of patients, limited historical data, and multiple anatomic and technical constraints. We present a case of symptomatic, refractory intracranial VA occlusive disease treated successfully via V4EA with patch angioplasty after failed endovascular intervention. Operative technique and the prior literature are briefly reviewed to formulate the best indications and strategies for obtaining improved outcomes.
A 56-year-old male was transferred to the inpatient neurology service from an outside institution with complaints of progressive and intermittent vertigo, ataxia, left-sided weakness, and tinnitus for the prior 10 days. The patient's symptoms were initially postcoital, but without associated headache. He additionally endorsed a single similar episode 6 months earlier that was self-limited. His past medical history was remarkable for hypertension and hyperlipidemia. He took no medications, and did not smoke or use tobacco.
Initial neurological examination revealed normal mental status, cranial nerve findings, motor examination, reflexes, sensation, drift, and cerebellar signs (including no evidence of dysdiadochokinesia). Magnetic resonance imaging (MRI) evaluation from the outside institution displayed evidence of multiple discrete foci of diffusion restriction in the inferior right cerebellar hemisphere. Computed tomography (CT) angiography obtained on admission at our institution showed absent left vertebral flow below posterior inferior cerebellar artery (PICA) and right VA origin stenosis [
(a) Preoperative axial MRI diffusion-weighted imaging depicting multiple, scattered, and punctate areas of restricted diffusion within the right cerebellar hemisphere. A large territory brainstem or cerebellar stroke was not evident. (b) Anteroposterior (AP) and (c) lateral preoperative DSA displaying severe, near-total occlusive focal plaque at the V4 segment. The ipsilateral PICA does not opacify. (d) 3D-reconstructed images from the postoperative CT-angiogram revealing patency and slight dilation at the endarterectomy site. A single clip at the transected posterior meningeal branch is also seen. (e) Postoperative AP and (f) lateral DSA 10 months postsurgery reveal patency without significant change at the endarterectomy site
Angiographic findings and procedures
Digital subtraction angiography revealed tandem 90% stenosis at the right VA origin and near occlusion (~99% stenosis) more distally just beyond the V3/V4 junction. The right PICA failed to opacify. The left VA was occluded at the origin, and did not reconstitute until the level of PICA via limited opacification from the contralateral circulation. Posterior communicating arteries, notably, were not apparent on the angiogram or pre-procedure CT angiography. Allcock's test, however, was not performed.
The right VA origin stenosis was successfully treated with deployment of a 4.0 × 12 mm balloon-mounted coronary stent (Multi-Link Vision, Abbott Vascular, Abbot Park, IL). The patient was loaded and subsequently maintained on clopidogrel and aspirin. However, further attempts to navigate a microwire and guide catheter beyond the stent and distal to the intracranial stenosis were unsuccessful due to proximal vessel tortuosity. The patient awoke without new neurological deficit. Repeat attempts via right brachial access the following day were similarly unsuccessful, and further attempts at treatment of the distal stenosis were aborted after concern for subintimal migration of the guidewire. Final angiographic runs did not reveal clear evidence of arterial dissection.
The patient again awoke without deficit, and CT imaging was negative for evidence of gross new ischemia or hemorrhage, but diffusion MRI showed numerous small hits in the cerebellar hemispheres. The patient's symptoms became increasingly labile over the following 2 weeks postprocedure in the hospital. Symptoms referable to the right PICA territory (as previous) were reproduced with systolic blood pressures less than 180 mmHg or slight deviation from the recumbent position. The senior author (PN) was then consulted for possible posterior-fossa revascularization. Clopidogrel was discontinued after the patient was transitioned to full heparin anticoagulation in anticipation of surgery.
Surgical management and technique [ Video 1 ]
Two weeks following the initial angiogram, the patient underwent right far lateral craniotomy in anticipation of occipital artery-PICA bypass as a first choice or endarterectomy as a second. Following placement of a lumbar drainage catheter, the patient was padded, placed in the radiolucent head-frame, and secured in the park-bench position. Somatosensory evoked potentials (SSEP) and electroencephalography baselines were obtained prior to incision. The patient's blood pressure was supported at preoperative levels with neosynephrine throughout the procedure.
A standard semilunar “hockey-stick” style myocutaneous flap was employed. The occipital artery was identified and partially dissected distally during the exposure. Prior to skin incision, audible flow could not be demonstrated along the course of the occipital artery, and the caliber of the artery ultimately proved feasible but suboptimal for bypass. Bony removal, including C1 laminectomy, proceeded in the standard fashion. Limited condylar drilling under microscopic visualization was performed to facilitate improved dural/vascular mobilization, eliminate any mechanical constraints, and optimize visualization and trajectory to the VA. The dura was incised along the superior and medial borders of the craniotomy, and tacked laterally. Details and tenets of the far lateral approach have been reviewed elsewhere, and are beyond the scope of the current report.
Following arachnoidal opening and cerebrospinal fluid (CSF) egress, the cerebellar hemispheres were allowed to relax with the aid of gravity. No fixed retractors were used during the procedure. The VA was identified intracranially and dissected above the origin of PICA proximally down to its dural cuff. The proximal dentate ligaments were also transected to facilitate improved mobilization of the brainstem. A marked color change of the VA wall consistent with atheromatous plaque was clearly identifiable proximal to the PICA origin, at the level of the twelfth nerve. Indocyanine green (ICG) angiography confirmed limited flow distal to the site of the plaque.
The dural cuff around the VA was then opened, and the entire circumference of the VA was freed from the dura. The remainder of the V3 segment along the sulcus arteriosus of the posterior C1 arch was skeletonized for proximal control, and venous bleeding was controlled with gentle tamponade and surgifoam. A posterior meningeal branch immediately proximal to the dural cuff was identified and clipped (later transected) for use in back-bleeding and assessment of patency. The occipital artery was deemed to be very small and of poor quality in relation to the VA. Therefore, we elected intraoperatively to proceed with arteriotomy and endarterectomy, reserving the occipital (OA)-to-PICA bypass option only in case a salvage procedure would be required.
Prior to endarterectomy, the field was irrigated until clear; systemic heparin was administered, and anesthesia was directed to achieve burst suppression with propofol for cerebral protection. Distal and proximal clips were applied, a linear arteriotomy was made, and then extended with Pott's scissors. Endarterectomy was performed without complication in the standard fashion with a Penfield 6 microdissector and microforceps [
Before foregoing primary closure and converting to bypass, we elected to proceed with one more attempt to (i) reinspect the lumen for evidence of iatrogenic dissection and/or subintimal flap, (ii) trim the arteriotomy walls for any residual thrombogenic debris (e.g. intimal tags) at the arteriotomy line, and (iii) to attempt patch angioplasty given some concern for iatrogenic stenosis during the first two attempts at primary closure. Given concern about the ischemia time, the decision was made not to harvest saphenous vein. A Gore-Tex (W. L. Gore and Associates, Flagstaff, AZ) patch was trimmed and sutured in place with 9-0 prolene, accommodating a slight dilation at the site of the arteriotomy. Frequent and repeated back-bleeding from both the proximal and distal ends of the VA and brisk irrigation with heparinized saline at the anastomosis line was performed at 2-minute intervals during closure to prevent thrombosis [
A final bit of dural sealant (DuraSeal, Covidien, Dublin, Ireland) was placed over the suture lines, and the dura was closed with running 5-0 prolene. As watertight closure at the dural cuff of the VA was not feasible, the dural defect was repaired with a combination of interrupted sutures followed by an onlay patch (Duragen, Integra, Plainsboro, NJ) and additional sealant. The cranial bone flap was replaced with titanium mini-plates, and the wound was closed in the standard layered fashion.
The patient again awoke without new neurological deficit. Postoperative day one angiogram revealed wide patency at the right VA origin and endarterectomy site. Surveillance MRI revealed new punctate foci of restricted diffusion in the left cerebellar hemisphere and subinsular region. Clopidogrel was resumed and aspirin was continued throughout the perioperative period following the satisfactory MRI. His lumbar drainage catheter, blood pressure parameters, and mobilization restrictions were weaned over the next 3 days. The patient was ultimately discharged to a neurorehabilitation facility at 5 days postoperatively, and returned to work 3 weeks later.
Ten-month follow-up angiography revealed satisfactory posterior circulation perfusion, wide patency at the treated VA segment, and mild (non flow-limiting) in-stent restenosis at the right VA origin [
Symptomatic intracranial VA (V4 segment) thrombo-occlusive disease, its natural history, and associated treatment strategies have not been as rigorously studied in comparison to stroke phenomena originating from the internal carotid artery.[
Surgical interventions for patients refractory to medical therapy consist principally of open arterial bypass or PTA and stent placement. Posterior fossa bypass procedures are technically demanding with significant risk of morbidity.[
Endovascular alternatives are well-reported,[
Lu et al. reported technical success in 24 patients who underwent both intracranial VA and VA origin stenting with a drug-eluting stent and had less than 30% residual stenosis.[
V4EA is an attractive alternative to other open revascularization strategies, particularly when endovascular management strategies have failed. Several inherent advantages of V4EA compared with bypass options are worth noting: V4EA preserves the native VA and tributaries, restores near-physiologic flow dynamics, and can typically be salvaged by bypass or thrombectomy[
Our complete list of indications for V4EA are listed in
Feasible, but suboptimal caliber of the donor occipital artery vessel Focal nature of the VA plaque. Previous authors have recommended that the endarterectomy be useful in cases of focal plaque.[ Accessibility of the VA plaque (proximal to the PICA origin). In a series of four cases, Ausman et al. reported that two patients with endarterectomies at the level or distal to PICA experienced infarction or VA sacrifice.[ Relative freedom of the remainder of the right VA from significant untreated stenosis Salvage opportunities could have been employed as a last resort either via an STA-SCA or OA-to-PICA bypass.[ Some authors reported that V4EA may be indicated in cases of hemodynamic or embolic etiologies[
Feasible, but suboptimal caliber of the donor occipital artery vessel
Focal nature of the VA plaque. Previous authors have recommended that the endarterectomy be useful in cases of focal plaque.[
Accessibility of the VA plaque (proximal to the PICA origin). In a series of four cases, Ausman et al. reported that two patients with endarterectomies at the level or distal to PICA experienced infarction or VA sacrifice.[
Relative freedom of the remainder of the right VA from significant untreated stenosis
Salvage opportunities could have been employed as a last resort either via an STA-SCA or OA-to-PICA bypass.[
Some authors reported that V4EA may be indicated in cases of hemodynamic or embolic etiologies[
The central tenets of our technique are similar to those described by previous authors,[
In our case, however, appropriate trimming of thrombogenic medial debris at the arteriotomy line and the small size of the VA necessitated an expansile patch angioplasty due to luminal constriction. Morgan et al.[
We agree with Anson and Spetzler that exposure via a far-lateral craniotomy plus C1 laminectomy is preferable to suboccipital access.[
We find the use of ICG in this case to be an excellent adjunct to micro-Doppler ultrasound to assess the patency of the vessel after endarterectomy, and find it to be a time-saving step over intraoperative digital subtraction angiography (DSA). DSA carries its own stroke risk, significantly increases operative time, and cannot localize the anatomic segment of stenosis directly in the operative field in real time under the operating microscope. The arteriotomy may then be appropriately limited to directly cover only the region of focal pathology, and the repair assessed under direction vision. We have previously found ICG useful in cases of bypass (unpublished data) to interrogate graft patency and have also used it in cases of aneurysms, arteriovenous malformations, and dural fistulae in lieu of or as an adjunct to formal angiography.[
The natural history of patients with symptomatic vertebrobasilar ischemic symptoms due to chronic bilateral VA occlusive disease is progressive, and poses significant challenges when refractory to medical therapy. Surgical treatment options depend largely on location and characteristics of the atheroma(s), and generally include PTA with or without stent placement, posterior circulation revascularization (bypass), extracranial VA reconstruction, or VA endarterectomy. We describe a nonautologous patch angioplasty and V4EA in a patient refractory to other treatments. An excellent outcome was demonstrated at 15-month follow-up.
1. Allen GS, Cohen RJ, Preziosi TJ. Microsurgical endarterectomy of the intracranial vertebral artery for vertebrobasilar transient ischemic attacks. Neurosurgery. 1981. 8: 56-9
2. Anson JA, Spetzler RF. Endarterectomy of the intradural vertebral artery via the far lateral approach. Neurosurgery. 1993. 33: 804-10
3. Ausman JI, Diaz FG, Pearce JE, de los Reyes RA, Leuchter W, Mehta B. Endarterectomy of the vertebral artery from C2 to posterior inferior cerebellar artery intracranially. Surg Neurol. 1982. 18: 400-4
4. Ausman JI, Diaz FG, Sadasivan B, Dujovny M. Intracranial vertebral endarterectomy. Neurosurgery. 1990. 26: 465-71
5. Ausman JI, Diaz FG, Vacca DF, Sadasivan B. Superficial temporal and occipital artery bypass pedicles to superior, anterior inferior, and posterior inferior cerebellar arteries for vertebrobasilar insufficiency. J Neurosurg. 1990. 72: 554-8
6. . Beneficial effect of carotid endarterectomy in symptomatic patients with high-grade carotid stenosis. North American Symptomatic Carotid Endarterectomy Trial Collaborators. N Engl J Med. 1991. 325: 445-53
7. Boulos AS, Deshaies EM, Qian J, Popp AJ. Preoperative stent placement for intradural vertebral artery stenosis from a rare xanthogranuloma. Case report. J Neurosurg. 2004. 101: 864-8
8. Brott TG, Hobson RW, Howard G, Roubin GS, Clark WM, Brooks W. Stenting versus endarterectomy for treatment of carotid-artery stenosis. N Engl J Med. 2010. 363: 11-23
9. Chimowitz MI, Lynn MJ, Derdeyn CP, Turan TN, Fiorella D, Lane BF. Stenting versus aggressive medical therapy for intracranial arterial stenosis. N Engl J Med. 2011. 365: 993-1003
10. Coward LJ, Featherstone RL, Brown MM. Percutaneous transluminal angioplasty and stenting for vertebral artery stenosis. Cochrane Database Syst Rev. 2000. 2: CD000516-
11. Coward LJ, McCabe DJ, Ederle J, Featherstone RL, Clifton A, Brown MM. Long-term outcome after angioplasty and stenting for symptomatic vertebral artery stenosis compared with medical treatment in the Carotid And Vertebral Artery Transluminal Angioplasty Study (CAVATAS): A randomized trial. Stroke. 2007. 38: 1526-30
12. Fiorella D, Chow MM, Anderson M, Woo H, Rasmussen PA, Masaryk TJ. A 7-year experience with balloon-mounted coronary stents for the treatment of symptomatic vertebrobasilar intracranial atheromatous disease. Neurosurgery. 2007. 61: 236-42
13. Hauth EA, Gissler HM, Drescher R, Jansen C, Jaeger HJ, Mathias KD. Angioplasty or stenting of extra- and intracranial vertebral artery stenoses. Cardiovasc Intervent Radiol. 2004. 27: 51-7
14. Hopkins LN, Budny JL. Complications of intracranial bypass for vertebrobasilar insufficiency. J Neurosurg. 1989. 70: 207-11
15. Hopkins LN, Martin NA, Hadley MN, Spetzler RF, Budny J, Carter LP. Vertebrobasilar insufficiency. Part 2. Microsurgical treatment of intracranial vertebrobasilar disease. J Neurosurg. 1987. 66: 662-74
16. Killory BD, Nakaji P, Gonzales LF, Ponce FA, Wait SD, Spetzler RF. Prospective evaluation of surgical microscope-integrated intraoperative near-infrared indocyanine green angiography during cerebral arteriovenous malformation surgery. Neurosurgery. 2009. 65: 456-62
17. Killory BD, Nakaji P, Maughan PH, Wait SD, Spetzler RF. Evaluation of angiographically occult spinal dural arteriovenous fistulae with surgical microscope-integrated intraoperative near-infrared indocyanine green angiography: Report of 3 cases. Neurosurgery. 2011. 68: 781-7
18. Lanzino G, Wakhloo AK, Fessler RD, Hartney ML, Guterman LR, Hopkins LN. Efficacy and current limitations of intravascular stents for intracranial internal carotid, vertebral, and basilar artery aneurysms. J Neurosurg. 1999. 91: 538-46
19. Levy EI, Horowitz MB, Koebbe CJ, Jungreis CC, Pride GL, Dutton K. Transluminal stent-assisted angiplasty of the intracranial vertebrobasilar system for medically refractory, posterior circulation ischemia: Early results. Neurosurgery. 2001. 48: 1215-21
20. Liu JR, Liu L, Chao M. Stent-assisted percutaneous transluminal angioplasty for intracranial vertebral artery stenosis: A reports of two cases. Zhejiang Da Xue Xue Bao Yi Xue Ban. 2006. 35: 683-6
21. Lu H, Zheng P, Zhang W. Long-term outcome of drug-eluting stenting for stenoses of the intracranial vertebrobasilar artery and vertebral ostium. J Neurointerv Surg. 2013. 5: 435-9
22. Mayberg MR, Wilson SE, Yatsu F, Weiss DG, Messina L, Hershey LA. Carotid endarterectomy and prevention of cerebral ischemia in symptomatic carotid stenosis. Veterans Affairs Cooperative Studies Program 309 Trialist Group. JAMA. 1991. 266: 3289-94
23. Morgan MK, Grinnell V, Little NS, Day MJ. Successful treatment of an acute thrombosis of an intracranial vertebral artery endarterectomy with urokinase. Neurosurgery. 1994. 35: 978-81
24. Mori T, Kazita K, Mori K. Cerebral angioplasty and stenting for intracranial vertebral atherosclerotic stenosis. AJNR Am J Neuroradiol. 1999. 20: 787-9
25. Muller-Kuppers M, Graf KJ, Pessin MS, DeWitt LD, Caplan LR. Intracranial vertebral artery disease in the New England Medical Center Posterior Circulation Registry. Eur Neurol. 1997. 37: 146-56
26. Natarajan SK, Ogilvy CS, Hopkins LN, Siddiqui AH, Levy EI. Initial experience with an everolimus-eluting, second-generation drug-eluting stent for treatment of intracranial atherosclerosis. J Neurointerv Surg. 2010. 2: 104-9
27. . Prognosis of patients with symptomatic vertebral or basilar artery stenosis. The Warfarin-Aspirin Symptomatic Intracranial Disease (WASID) Study Group. Stroke. 1998. 29: 1389-92
28. Raabe A, Nakaji P, Beck J, Kim LJ, Hsu FP, Kamerman JD. Prospective evaluation of surgical microscope-integrated intraoperative near-infrared indocyanine green videoangiography during aneurysm surgery. J Neurosurg. 2005. 103: 982-9
29. . Randomised trial of endarterectomy for recently symptomatic carotid stenosis: Final results of the MRC European Carotid Surgery Trial (ECST). Lancet. 1998. 351: 1379-87
30. Rasmussen PA, Perl J, Barr JD, Markarian GZ, Katzan I, Sila C. Stent-assisted angioplasty of intracranial vertebrobasilar atherosclerosis: An initial experience. J Neurosurg. 2000. 92: 771-8
31. Sato T, Sasaki T, Suzuki K, Matsumoto M, Kodama N, Hiraiwa K. Histological study of the normal vertebral artery--etiology of dissecting aneurysms. Neurol Med Chir (Tokyo). 2004. 44: 629-35
32. Shin HK, Yoo KM, Chang HM, Caplan LR. Bilateral intracranial vertebral artery disease in the New England Medical Center, Posterior Circulation Registry. Arch Neurol. 1999. 56: 1353-8
33. Song L, Li J, Gu Y, Yu H, Chen B, Guo L. Drug-eluting vs. bare metal stents for symptomatic vertebral artery stenosis. J Endovasc Ther. 2012. 19: 231-8
34. . Stenting of Symptomatic Atherosclerotic Lesions in the Vertebral or Intracranial Arteries (SSYLVIA): Study results. Stroke. 2004. 35: 1388-92
35. Wilkinson IM. The vertebral artery. Extracranial and intracranial structure. Arch Neurol. 1972. 27: 392-6