Extracranial carotid aneurysms: a new look at an old problem.

Abstract

As difficult as it is to imagine now, Sir Astley Cooper performed the first successful operation for an extracranial carotid aneurysm in London in 1808, more than 35 years before Charles Dickens' A Christmas Carol illustrated the cobblestoned simplicity of that great city even in 1843. The patient, who also deserves a lot of credit, was a 50-year-old laborer who apparently was hypertensive, as indicated by Cooper's note that “the pulsation of the tumor was remarkably strong on that day,” as well as by the fact that he eventually died with an intracranial hemorrhage 14 years later.1Cooper A Account of the first successful operation performed on the common carotid artery for aneurysm, in the year 1808: with the post-mortem examination, in 1821.Guy's Hospital Rep. 1836; 1: 53-59Google Scholar The common carotid artery was ligated proximally to a painful bulbar aneurysm of the internal carotid artery (ICA), which, according to the barnyard nomenclature that was so popular at the time, was “about the size of a pullet's egg.” The postoperative length of stay was a bit long by today's standards (because of a smoldering wound infection, the patient did not leave Guy's Hospital until 3 months later), but he was able to return to work until his death in 1822 from a hemorrhagic cerebral infarction that was shown through autopsy to have occurred on the same side as the carotid ligation. Sir Astley deserves high marks for more than just a good long-term result in this particular patient. For one thing, he attended the autopsy himself and demonstrated a large posterior communicating branch supplying collateral circulation to the ipsilateral middle cerebral artery. Furthermore, he may have also performed the first unsuccessful carotid ligation for an ICA aneurysm in another patient 2½ years earlier, but he had the surgical temerity to try it again.1Cooper A Account of the first successful operation performed on the common carotid artery for aneurysm, in the year 1808: with the post-mortem examination, in 1821.Guy's Hospital Rep. 1836; 1: 53-59Google Scholar Nathan Winslow and his colleagues at the University of Maryland eventually chronicled the rich history of ICA aneurysms in an exhaustive review of all 124 cases that had been reported in the literature until 1936.2Winslow H Extracranial aneurysm of the internal carotid artery: history and analysis of the cases registered up to Aug 1, 1925.Arch Surg. 1926; 13: 689-729Crossref Google Scholar, 3Shipley AM Winslow H Walker WW Aneurysm of the cervical portion of the internal carotid artery: an analytical study of the cases recorded in the literature between August 1, 1925, and July 31, 1936. Report of two new cases.Ann Surg. 1937; 105: 673-698Crossref PubMed Google Scholar A total of 82 patients were treated by carotid ligation, with an operative mortality rate of 28% and either “cure or improvement” in 71%. No operations were performed in the other 42 patients, with a mortality rate of 71% and spontaneous cure or improvement in only 12%. Seventy-six (61%) of the ICA lesions that were described in these early reports represented pseudoaneurysms related to previous trauma or to arterial “erosion” from middle ear infections or tonsillitis, the latter prompting Winslow to make the following remarks in 1926: But it is not so much the rarity of this lesion, when it does occur, that commands our attention as its propensity to imitate peritonsillar abscess, which habit of mimicry has led on more than one occasion to its lancing, with a mortal hemorrhage. The majority of these patients should recover if the aneurysm is promptly recognized and properly treated, but an overwhelming proportion die under dilatory, blundering or pernicious tactics.2Winslow H Extracranial aneurysm of the internal carotid artery: history and analysis of the cases registered up to Aug 1, 1925.Arch Surg. 1926; 13: 689-729Crossref Google Scholar By the 1970s, direct arterial reconstruction and/or autogenous vein grafting had definitely supplanted ligation and other “dilatory, blundering or pernicious tactics” for the management of extracranial carotid aneurysms, irrespective of their etiology.4Rhodes EL Stanley JC Hoffman GL Cronenwett JL Fry WJ Aneurysms of extracranial carotid arteries.Arch Surg. 1976; 111: 339-343Crossref PubMed Scopus (99) Google Scholar Elsewhere in this issue of the Journal of Vascular Surgery , El-Sabrout and Cooley5El-Sabrout R Cooley DA Extracranial carotid artery aneurysm: Texas Heart Institute experience.J Vasc Surg. 2000; 31: 702-712Abstract Full Text Full Text PDF PubMed Scopus (280) Google Scholar of the Texas Heart Institute (THI) and Rosset et al6Rosset E Albertini JH Magnan PE Branchereau A Surgical treatment of extracranial carotid artery aneurysms.J Vasc Surg. 2000; 31: 713-723Abstract Full Text Full Text PDF PubMed Scopus (145) Google Scholar of Marseille provide readers with a contemporary view of these aneurysms; each article presents a slightly different perspective on the basis of a unique patient population. Both of these series confirm that true “atherosclerotic” carotid aneurysms still rarely occur in the neck; they accounted for only 23 (35%) of the 65 patients at the THI from 1960 to 1995, and for nine (36%) of the 25 patients in Marseille from 1980 to 1997. Otherwise, the principal focus of the THI report is obviously on the surgical treatment of aneurysms near the carotid bifurcation, whereas the article from Marseille primarily emphasizes lesions in the distal cervical segment of the ICA at the base of the skull. The 23 procedures performed for atherosclerotic carotid aneurysms at the THI represent just 0.5% of the 4991 carotid operations that were done at that busy center during the preceding 35 years. Most of the patients (n = 38, 58%) described by El-Sabrout and Cooley had pseudoaneurysms related to Dacron patches that had been applied at the time of previous carotid endarterectomy, including seven for which silk sutures had been used and another thirteen that ultimately became infected. Coincidentally or not, these data are remarkably similar to the proportion of patients (61%) who had ICA pseudoaneurysms in the 19th and early 20th centuries,2Winslow H Extracranial aneurysm of the internal carotid artery: history and analysis of the cases registered up to Aug 1, 1925.Arch Surg. 1926; 13: 689-729Crossref Google Scholar, 3Shipley AM Winslow H Walker WW Aneurysm of the cervical portion of the internal carotid artery: an analytical study of the cases recorded in the literature between August 1, 1925, and July 31, 1936. Report of two new cases.Ann Surg. 1937; 105: 673-698Crossref PubMed Google Scholar an observation that may only underscore once again the relative rarity of true carotid aneurysms during any period of history. Possibly the most interesting aspect of this and an earlier THI report on the same topic7Knight GC Hallman GL Reul GJ Ott DA Cooley DA Surgical management of extracranial carotid artery aneurysms: report of 17 cases.Tex Heart Inst J. 1988; 15: 91-97PubMed Google Scholar is the authors' preference for partial aneurysm excision and patch angioplasty, rather than resection and direct reanastomosis or interposition grafting, for 30 (79%) of the 38 pseudoaneurysms and, perhaps more importantly, for nine (39%) of the 23 atherosclerotic aneurysms in their series. After opening the full length of the lesion with a conventional arteriotomy and excising the old patch if one was present, they simply trimmed excess width from the margins of the arteriotomy before repairing it in a standard fashion, using Dacron patches in 34 patients, vein patches in four, and a polytetrafluorethylene patch in one. A couple of important technical features regarding this approach are left unstated in the THI report and for this reason can only be assumed. First, the authors almost certainly performed an endarterectomy during many of these procedures to remove the loose debris and mural thrombus that make atherosclerotic carotid aneurysms so dangerous from a neurologic standpoint. This is also an interesting consideration in the sense that their satisfaction with only partial excision of true aneurysms could suggest that new aneurysmal expansion is unlikely to occur once the principal elastin component of the arterial wall (ie, the internal elastic lamina in the medial layer) has been removed during the endarterectomy, thus converting the residual artery basically into a collagenous conduit. Second, despite the fact that 13 of the 38 pseudoaneurysms in this series were associated with infected Dacron patches, only eight were repaired with autogenous patches (n = 4) or grafts (n = 2), with primary arteriotomy closure (n = 1), or with ligation alone (n = 1). This implies that synthetic material was used to replace infected Dacron patches in at least five patients whose specific outcomes never are mentioned. Six patients (16%) eventually did have carotid infections after pseudoaneurysm procedures, but there is no information regarding which patients they were. One can only conclude that, if the authors were able to replace an infected Dacron patch with yet another synthetic, there must have been some fairly extenuating circumstances. There were four deaths (6%), five major strokes (7.5%), and one minor stroke in the THI series, with a combined stroke and mortality rate (CSM) of 10%, a figure that is nearly identical to the CSM (9%) for 325 patients who underwent replacement grafts (n = 114, 46%) or some other type of surgical treatment for extracranial carotid aneurysms in 12 published series cited by El-Sabrout and Cooley in their literature review. In comparison, however, the CSMs for all patients who received carotid ligation (n = 26) or observation without intervention (n = 43) in these selected references were 12% and 21%, respectively. Collectively, therefore, surgical treatment appears to be quite appropriate for most aneurysms that are located near the carotid bifurcation even though its perioperative stroke risk clearly seems to be higher than that for routine carotid endarterectomy, probably because of the embolic potential of these aneurysms and the tendency for short venous replacement grafts to “kink” and occasionally to become occluded unless they are tailored to precisely the correct length. By the way, one method that can be used to avoid kinking is to construct the vein graft over a straight ICA shunt so that the appropriate length of the graft can be fully appreciated before blood flow has been restored.8Painter TA Hertzer NR Beven EG O'Hara PJ Extracranial carotid aneurysms: report of six cases and review of the literature.J Vasc Surg. 1985; 2: 312-318PubMed Scopus (68) Google Scholar The report from Marseille that also is found in this issue of the Journal cannot easily be compared with other typical series of extracranial carotid aneurysms simply because it addresses a subset of ICA lesions about which even less is known. Only nine of the 25 aneurysms encountered by Rosset et al were atherosclerotic in origin and involved the proximal cervical segment of the ICA, whereas the remaining 16 (64%) aneurysms were located within 2 cm of the skull base and were related to trauma (n = 3) or, in one way or another, to fibromuscular dysplasia with or without prior spontaneous dissection (n = 13). The anatomic exposure that these authors recommend already has been described, most recently by another group in Marseille,9Alimi YS DiMauro P Fiacre E Magnan J Juhan C Blunt injury to the internal carotid artery at the base of the skull: six cases of venous graft restoration.J Vasc Surg. 1996; 24: 249-257Abstract Full Text Full Text PDF PubMed Scopus (35) Google Scholar and requires the identification, mobilization, resection, or transection of so many sensitive structures (including the external auditory canal) that are unfamiliar to most vascular surgeons that the multidisciplinary surgical approach adopted by Rosset et al would undoubtedly be necessary at other centers as well. The authors' results are generally excellent, but they come at a price. Twenty-four vein grafts and one direct ICA repair were done with only one minor stroke (4%), one early graft thrombosis, and no deaths. Nevertheless, 11 patients (44%) experienced postoperative cranial nerve dysfunction (10 facial, one glossopharyngeal) that persisted, on average, for the next 7 months. The troubling feature about all of this is that so little information is available regarding the natural history of ICA aneurysms or pseudoaneurysms caused by the complications of fibromuscular dysplasia extending to the skull base. Are they sufficiently dangerous to justify operations of this magnitude? Could even symptomatic patients be managed just as safely, or perhaps even more so, by modern antiplatelet therapy or oral anticoagulation with warfarin? The same questions were asked nearly 20 years ago,10Friedman WA Kelly DL in discussion of Hodge CJ Lee SH Spontaneous dissecting cervical carotid artery aneurysm.Neurosurgery. 1982; 10: 93-95Crossref PubMed Scopus (10) Google Scholar but the literature concerning the natural history of these lesions remains virtually nonexistent. Until some reliable answers are forthcoming, it is conceivable that at least some of the elegant procedures reported from Marseille could merely represent big operations. In this particular series, however, they were big operations that were done very well. Please see the related articles by El-Sabrout and Cooley on pages 702-12 and by Rosset et al on pages 713-23. Extracranial carotid artery aneurysms: Texas Heart Institute experienceJournal of Vascular SurgeryVol. 31Issue 4PreviewBackground and Purpose: Aneurysms of the extracranial carotid artery (ECA) are rare. Large single-institution series are seldom reported and usually are not aneurysm type–specific. Thus, information about immediate and long-term results of surgical therapy is sparse. This review was conducted to elucidate etiology, presentation, and treatment for ECA aneurysms. Methods: We retrospectively reviewed the case records of the Texas Heart Institute/St Luke's Episcopal Hospital, Houston, and found 67 cases of ECA aneurysms treated surgically (the largest series to date) between 1960 and 1995: 38 pseudoaneurysms after previous carotid surgery and 29 atherosclerotic or traumatic aneurysms. Full-Text PDF Open ArchiveSurgical treatment of extracranial internal carotid artery aneurysmsJournal of Vascular SurgeryVol. 31Issue 4PreviewPurpose: Extracranial internal carotid artery aneurysms (EICAs) can be treated by carotid ligation or surgical reconstruction. In the consideration of the risk of stroke after internal carotid artery (ICA) occlusion, the aim of this study was to report the results of reconstructive surgery for these aneurysms, including lesions located at the base of the skull. Methods: From 1980 to 1997, 25 ICA reconstructions were performed for EICA: 22 male patients and 3 female patients (mean age, 54.4 years). Full-Text PDF Open Archive