Surgical management of aneurysms of the distal extracranial internal carotid artery

Osteovascular Conflicts in the Neck Region and Cerebrovascular Events: Illustrative Cases and Literature Review

STUDY DESIGN

Literature Review.

OBJECTIVE

Abnormal bone structures in the neck can cause headache, neck pain, and difficulty swallowing, but also cerebrovascular events. We introduce the term "osteovascular conflicts" to describe this phenomenon. The objective of this study was to conduct a literature review of such conflicts involving the anterior and posterior cerebral circulation. Furthermore, we aimed at presenting additional illustrative cases from our institution both for increasing awareness for unusual osteovascular conflicts, and for assessing the practice and care of such patients.

METHODS

We focused on osteovascular conflicts in the neck leading to cerebrovascular events related to an abnormal bone structure causing arterial or venous compression, dissection, and/or occlusion. We excluded pure vascular forms without cerebrovascular repercussions. Our PubMed/MEDLINE search for articles published in any language and for which an English abstract was available (from 1966 to 2022) included Eagle's neurovascular, bow hunter's syndrome, and golfer's stroke, excluding trauma-induced artery dissections or compressions and those concerning systemic bone disorders. We also provided illustrative cases collected by the authors.

RESULTS

All studies were either case reports or small case series. We found 82 cases of Eagle's neurovascular, 258 of bow hunter's syndrome, and 17 golfer's stroke cases. Mean ages were 52, 48, and 47 years, respectively. Male predominance was evident: 81% for Eagle's, 74% for bow hunter's, and 93% for golfer's.

CONCLUSION

Osteovascular conflicts are rare but important causes of cerebrovascular events and often go unrecognised. A greater awareness of cerebrovascular symptoms related to these conflicts can facilitate early diagnosis and treatment.

Management strategy for extracranial carotid artery aneurysms: A single-center experience

ABSTRACT

This single-center, retrospective study aimed to describe the anatomic and clinical characteristics of extracranial carotid artery aneurysms (ECAAs) and to compare various ECAA management strategies in terms of outcomes.A total of 41 consecutive patients, who underwent treatment for ECAAs between November 1996 and May 2020, were included in this study. The ECAAs were anatomically categorized using the Attigah and Peking Union Medical College Hospital (PUMCH) classifications. The possible study outcomes were restenosis or occlusion of the ipsilateral carotid artery after treatment and treatment-associated morbidity or mortality.The 41 patients were stratified into three groups according to the management strategies employed: surgical (n = 25, 61.0%), endovascular (n = 10, 24.4%), and conservative treatment (n = 6, 14.6%). A palpable, pulsatile mass was the most common clinical manifestation (n = 16, 39.0%), and degenerative aneurysms (n = 29, 65.9%) represented the most common pathogenetic or etiological mechanism. According to the Attigah classification, type I ECAAs (n = 24, 58.5%) were the most common. Using the PUMCH classification, type I ECAAs (n = 26, 63.4%) were the most common. There was a higher prevalence of Attigah type I ECAAs among patients who underwent surgical treatment compared with those who underwent endovascular treatment (64.0% vs 40.0%, P = .09), whereas patients with PUMCH type IIa aneurysms were more likely to receive endovascular treatment (12.0% vs 30.0%). False aneurysms were more likely to be treated using endovascular techniques (20% vs 70%, P = 0.02). Except for two early internal carotid artery occlusions (one each among patients who underwent surgical and endovascular treatments, respectively), there were no early or late restenoses or occlusions during follow-up. Cranial nerve injuries were noted in three patients after surgical treatment, and late ipsilateral strokes occurred in two patients (one each among patients who underwent endovascular and conservative treatment, respectively). There were no other treatment-associated complications or deaths during the study period.

CONCLUSIONS

Both surgical and endovascular treatments could be performed safely for ECAAs with good long-term results according to anatomic location and morphology.

Surgical access to the distal cervical segment of the internal carotid artery and to a high carotid bifurcation – integrative literature review and protocol proposal

Abstract Several different maneuvers have been described for obtaining access to the distal cervical segment of the internal carotid artery or to a high carotid bifurcation. However there are different approaches to systematization of these techniques. The objective of this study is to review the techniques described and propose a practical protocol to support selection of the most appropriate technique for each case. The review is based on the results of database searches on PubMed Central, the Virtual Health Library (BVSalud), and SciELO for articles on the subject published in English or Portuguese from 1980 to 2021. Among the different maneuvers described, it appears reasonable that the first two steps should be to obtain access at the sternocleidomastoid muscle, followed by section or retraction of the digastric muscle posterior belly. If needed, temporary unilateral mandibular subluxation is an additional resource that is preferable to division of the styloid apparatus process, because of its lesser potential for morbidity. Even wider exposure can be obtained using mandibular osteotomies.

Acesso cirúrgico ao segmento cervical distal da artéria carótida interna e à bifurcação carotídea alta – revisão integrativa da literatura e proposta de protocolo

Several different maneuvers have been described for obtaining access to the distal cervical segment of the internal carotid artery or to a high carotid bifurcation. However there are different approaches to systematization of these techniques. The objective of this study is to review the techniques described and propose a practical protocol to support selection of the most appropriate technique for each case. The review is based on the results of database searches on PubMed Central, the Virtual Health Library (BVSalud), and SciELO for articles on the subject published in English or Portuguese from 1980 to 2021. Among the different maneuvers described, it appears reasonable that the first two steps should be to obtain access at the sternocleidomastoid muscle, followed by section or retraction of the digastric muscle posterior belly. If needed, temporary unilateral mandibular subluxation is an additional resource that is preferable to division of the styloid apparatus process, because of its lesser potential for morbidity. Even wider exposure can be obtained using mandibular osteotomies.

Clinical utility and versatility of the petrous segment of the internal carotid artery in revascularization

Direct approaches to high cervical lesions, including tumors and aneurysms, carry significant risks. This renders alternative approaches desirable, with vascular disease amenable to exclusion and revascularization to the intracranial circulation, including the petrous or supraclinoid segments of the internal carotid artery (ICA). The cervicopetrous ICA bypass via saphenous venous grafting has proven an effective strategy for treating and excluding these lesions. In current practice, this is performed via an extradural subtemporal approach to access the petrous segment of the ICA and a cervical incision for access to the cervical ICA. The venous graft is alternately tunneled subcutaneously or in situ through the cervical ICA, with the latter eschewing external compression, kinking, and torsion, which increases risk of graft thrombosis with the former. Maxillary or middle meningeal arteries may also serve as donors to the petrous ICA. Moreover, the petrous ICA may be used as a donor in revascularization procedures, to the supraclinoid segment of the ICA and the middle cerebral artery, with petrous supraclinoid and petrous-MCA bypasses described. Clinical utility and operative approaches bypassing to or from the petrous ICA in revascularization procedures are reviewed and discussed.

Carotid Aneurysm Review

Aneurysms of the carotid artery are rare with multiple underlying etiologies. Treatment is largely open surgery but medical and endovascular therapies have been used based on presentation, anatomy, and etiology. There is a moderate amount of retrospective case series data on surgical results but no prospective data or data comparing open versus endovascular therapy exists. Much research is still needed but difficult to obtain in this rare disease process.

A Rare Cause of Juvenile Stroke: Extracranial Carotid Artery Aneurysm with Venous Complete Reconstruction of the Carotid Bifurcation

Extracranial carotid artery aneurysms (ECAA) are a rare cause of embolic stroke. The underlying etiology is variable, with atherosclerosis being the most common entity in older subjects. Several treatments have been developed over the last 20 years, but the preferred method remains unknown. Notwithstanding the widespread use of endovascular techniques, surgical reconstruction by means of a bifurcated venous bypass graft should be applied in younger patients. In this way, it is possible to avoid major concerns about the development of long-term intrastent restenosis, and also to spare the external carotid artery which represents the main branch for the ipsilateral cerebral and facial perfusion. We propose ECAA resection and interposition of the inverted great saphenous vein to both the internal and external carotid artery by means the use of a tributary, i.e., the Giacomini vein.

Eagle Syndrome Presenting after Blunt Trauma

As classically described, Eagle syndrome is an entity where patients develop pain or neurologic manifestations arising from an elongated styloid process and/or an ossified stylohyoid ligament irritating or compressing adjacent cranial nerves or the carotid arteries. Over the past few years, there have been reports of actual injury to the internal carotid artery with dissection, occlusion, and strokes. We present 3 cases identified after blunt trauma: 1 due to carotid compression and 2 due to actual injury to the internal carotid artery. Eagle syndrome should be a consideration in any patient with a carotid injury due to blunt trauma or suffering a syncopal episode which led to blunt trauma. Carotid stenting is an effective treatment modality for injury to the carotid artery when anticoagulation is contraindicated. Styloidectomy is performed for symptoms due to carotid artery compression or if there is concern for future carotid injury from the styloid process.

Management of extracranial carotid artery aneurysm

INTRODUCTION

Aneurysms of the extracranial carotid artery (ECAA) are rare. Several treatments have been developed over the last 20 years, yet the preferred method to treat ECAA remains unknown. This paper is a review of all available literature on the risk of complications and long-term outcome after conservative or invasive treatment of patients with ECAA.

METHODS

Reports on ECAA treatment until July 2014 were searched in PubMed and Embase using the key words aneurysm, carotid, extracranial, and therapy.

RESULTS

A total of 281 articles were identified. Selected articles were case reports (n = 179) or case series (n = 102). Papers with fewer than 10 patients were excluded, resulting in the final selection of 39 articles covering a total of 1,239 patients. Treatment consisted of either conservative treatment in 11% of the cases or invasive treatment in 89% of the cases. Invasive treatment comprised surgery in 94%, endovascular approach in 5%, and a hybrid approach in 1% of the patients. The most common complication described after invasive therapy was cranial nerve damage, which occurred in 11.8% of patients after surgery. The 30 day mortality rate and stroke rate in conservatively treated patients was 4.67% and 6.67%, after surgery 1.91% and 5.16%. Information on confounders in the present study was incomplete. Therefore, adjustments to correct for confounding by indication could not be done.

CONCLUSIONS

This review summarizes the largest available series in the literature on ECAA management. The number of ECAAs reported in current literature is scarce. The early and long-term outcome of invasive treatment in ECAA is favorable; however, cranial nerve damage after surgery occurs frequently. Unfortunately, due to limitations in reporting of results and confounding by indication in the available literature, it was not possible to determine the optimal treatment strategy. There is a need for a multicenter international registry to reveal the optimal treatment for ECAA.

C1 transverse process-hyoid bone line for preoperative evaluation of the accessible internal carotid artery on carotid endarterectomy: technical note

BACKGROUND

The preoperative imaging diagnosis of the distal portion of the internal carotid artery (ICA) is extremely important for carotid endarterectomy (CEA). Herein the authors defined a line from the C1 transverse process to the hyoid bone (C1-H line) and evaluated whether the line can be used to predict an accessible ICA in CEA.

METHODS

A cross point between the C1-H line and distal ICA was analyzed using three-dimensional computerized tomographic angiography (3D-CTA) in 20 patients. The C1-H line was compared to the line drawn from the mastoid process to the mandible (M-M line). Intraoperative exposure of the distal ICA was evaluated using both lines. Furthermore, the distance of each line from the C2 vertebra was measured to identify the distance difference of each line in relation to the cervical posture.

RESULTS

A distal ICA exposed at a cross point of the C1-H line corresponded well with the intraoperative findings. The cross point between the C1-H line and distal ICA was positioned at an average of 7.0 ± 0.7 mm cranially in comparison to the M-M line. The C1-H line showed smaller distance differences at different cervical positions than the M-M line. The C1-H line moved an average of 2.8 ± 2.5 mm from a cervical neutral position to an extensional one in the perpendicular direction.

CONCLUSION

The C1-H line measured by 3D-CTA is a simple and useful indicator of the distal ICA exposure in the preoperative diagnosis for CEA.

Endovascular treatment of the extracranial carotid pseudoaneurysms resulting from stab penetrating injury using overlapping bare stents

Injury pertaining to the common carotid artery may result in complete or partial arterial transection, pseudoaneurysms, or arteriovenous connections. Endovascular treatment option of the pseudoaneurysm has already been established with favorable success rate and minimal morbidity. Our purpose is to report one 18-year-old male patient having 2 traumatic pseudoaneurysms as a result of penetrating stab injury in the extracranial common carotid. The patient was successfully treated using 2 overlapping bare-metal stents. The 2 common carotid pseudoaneurysms had different degree inflow angles defined as the space between the lines indicating the direction of blood flow from the parent artery and through the aneurysmal neck to the dome. Computed tomography angiography was utilized to follow the evolution of the pseudoaneurysms until total occlusion was demonstrated. The treatment modality used in this report represents an alternative approach of the endovascular treatment for the extracranial carotid pseudoaneurysm.

Technical options for the treatment of extracranial carotid aneurysms

Extracranial carotid artery aneurysm (ECAA) is an uncommon but serious condition. The morbidity and mortality of ECAA are assumed to be high when untreated. ECAA treatment presents a challenge because of accessibility of the carotid artery and lack of evidence-based guidelines. When exclusion of the aneurysm is considered, surgical resection of the aneurysm with reconstruction of blood flow is still considered the gold standard. Several alternative and endovascular approaches are discussed.

Distal cervical internal carotid artery stenosis

This report describes a case of distal cervical internal carotid artery (ICA) occlusive lesion managed by saphenous interposition vein graft after exposure of the ICA up to the skull base. The skull base approach described herein emphasizes the mobilization of the mandible without mandibular osteotomy or disarticulation. Instead, the stylomandibular and stylosphenoidal ligaments are resected to allow mandibular mobilization. In addition, the distal ICA lesion represented a form of diffuse intimal thickening without any plaque formation. This required the resection of the thickened, stenotic segment and reconstruction of the distal cervical ICA with a saphenous interposition graft. The surgical management implications of diffuse intimal thickening are discussed.

Endovascular Stenting of Extracranial Carotid and Vertebral Artery Dissections: A Systematic Review of the Literature

BACKGROUND:

Carotid and vertebral artery dissections are a leading cause of stroke in young individuals.

OBJECTIVE:

To examine the published safety and efficacy of endovascular stenting for extracranial artery dissection.

METHODS:

We conducted a systematic review of the literature to identify all cases of endovascular management of extracranial carotid and vertebral artery dissections.

RESULTS:

For carotid dissections, our review yielded 31 published reports including 140 patients (153 vessels). Reported etiologies were traumatic (48%, n = 64), spontaneous (37%, n = 49), and iatrogenic (16%, n = 21). The technical success rate of stenting was 99%, and the procedural complication rate was 1.3%. Mean angiographic follow-up was 12.8 months (range, 2-72 months) and revealed in-stent stenosis or occlusion in 2% of patients. Mean clinical follow-up was 17.7 months (range, 1-72 months), and neurological events were seen in 1.4% of patients. For vertebral artery dissections, our review revealed 8 reports including 10 patients (12 vessels). Etiologies were traumatic (60%, n = 6), spontaneous (20%, n = 2), and iatrogenic (20%, n = 2). There was a 100% technical success rate. The mean angiographic follow-up period was 7.5 months (range, 2-12 months). No new neurological events were reported during a mean clinical follow-up period of 26.4 months (range, 3-55 months).

CONCLUSION:

Endovascular management of extracranial arterial dissection continues to evolve. Current experience shows that this treatment option is safe and technically feasible. Prospective randomized trials compared with medical management are needed to further elucidate the role of stenting.

Eagle syndrome presenting with external carotid artery pseudoaneurysm

Eagle syndrome refers to a clinical syndrome caused by the abnormal elongation of the styloid process with calcification/ossification of the stylohyoid ligament. We present the first reported case of Eagle syndrome resulting in an external carotid artery (ECA) pseudoaneurysm. A patient presented to emergency room with an expanding, painful right-neck mass. CT angiography with three-dimensional volume rendering showed a bilobed 4.0-cm right ECA pseudoaneurysm and bilateral ossification of the stylohyoid ligaments with a sharpened edge of the right styloid process at the level of the carotid artery. Aneurysmectomy was performed, and a common carotid to internal carotid bypass with reversed saphenous vein restored arterial continuity. Local resection of the styloid process with a rotational sternocleidomastoid flap was performed. The pathology report was consistent with a diagnosis of a pseudoaneurysm. A six-month clinical follow-up confirmed the complete resolution of symptoms with no neurological deficits.

Extracranial carotid artery pseudoaneurysm presenting with embolic stroke in a pediatric patient. Case report

Extracranial carotid artery (CA) aneurysms are rare in the pediatric population and are usually the result of connective tissue disorders, traumatic dissection, or infection. The authors present the case of a large calcified internal carotid artery pseudoaneurysm of obscure origins presenting with embolic stroke in a child. Aneurysm excision and CA reconstruction would have been extremely difficult due to the distal location of the lesion, and CA ligation was contraindicated due to a failed balloon test occlusion. Therefore, after anticoagulation therapy, the patient was treated endovascularly with a covered stent and complete exclusion of the aneurysm from the circulation. The patient recovered all neurological function and has remained in excellent condition. A follow-up angiogram performed at 6 months showed no recurrence or stenosis.

Petrous carotid artery pseudoaneurysm in bilateral carotid fibromuscular dysplasia: treatment by means of self-expanding covered stent

BACKGROUND

Pseudoaneurysms of the petrous carotid artery may occur in the setting of trauma, dissection, invasive tumors, or as a complication of surgery. These aneurysms may grow and constitute a potential source of thromboembolic complications or rupture.

CASE DESCRIPTION

We present a patient with bilateral carotid FMD presenting with a large petrous pseudoaneurysm. Because carotid occlusion was not appropriate, a self-expandable covered stent was implanted. This treatment allowed complete exclusion of the pseudoaneurysm and preservation of the parent artery.

CONCLUSION

The accepted treatment of psuedoaneurysms located at petrous ICA is either sacrifice of the carotid artery or exclusion of the aneurysm from the preserved carotid artery. These procedures have specific limitations, and they are technically demanding and associated with a substantial morbidity rate. The endovascular treatment of these lesions is the preferred alternative. Among the various endovascular techniques that have been tested so far, we propose self-expandable covered stents as ideal for treating arterial aneurysms and pseudoaneurysms of the petrous and cavernous carotid segments.

Mandibular Subluxation for Distal Cervical Exposure of the Internal Carotid Artery

INTRODUCTION

Surgical access to the distal segment of the cervical internal carotid artery (ICA) is a challenge because of the limited exposure imposed by bony structures and concern regarding cranial nerve and major vasculature injury. Our objective is to quantify the additional exposure of the distal cervical ICA obtained with mandibular subluxation (MS) compared with maneuvers that do not mobilize the mandible.

METHODS

Thirty dissections of the cervical ICA and common carotid artery bifurcation were performed on fresh cadavers. The length of the ICA exposure was measured from the carotid bifurcation to the most distally exposed ICA after sectioning the posterior belly of the digastric and stylohyoid muscles, removal of the styloid process, and MS.

RESULTS

After MS, a 5.52 +/- 1.00 cm mean exposure of the cervical ICA was obtained. Comparison between the second and third measures revealed an average additional exposure of the ICA of 0.77 cm, corresponding to an additional 16.2% (P < .001). Neck length, sex, and age showed no correlation with the ICA exposure.

CONCLUSION

MS provided an additional exposure of the distal segment of the cervical ICA and may be useful in selected cases to improve access. However, staged maneuvers should be used, and the need for MS depends on the level and extension of the lesion.

Carotid Artery Aneurysms: Serbian Multicentric Study

This multicentric Serbian study presents the treatment of 91 extracranial carotid artery aneurysms in 76 patients (13 had bilateral lesions). There were 61 (80.3%) male and 15 (19.7%) female patients, with an average age of 61.4 years. The aneurysms were caused by atherosclerosis in 73 cases (80.2%), trauma in six (6.6%), previous carotid surgery in six (6.6%), tuberculosis in one (1.1%), and fibromuscular dysplasia in five (5.5%). The majority (61 cases or 67%) of the aneurysms involved the internal carotid artery, 29 (31.9%) the common carotid artery bifurcation, and one (1.1%) the external carotid artery. Forty-five (49.4%) aneurysms were fusiform, while 46 (50.6%) were saccular. Twenty-nine (31.9%) cases were totally asymptomatic at the time of diagnosis. The remainder presented with compression in 14 (15.4%) cases, stroke in 11 (12.1%) cases, transient ischemic attack in 33 (36.3%) cases, and rupture in four (4.4%) cases. In cases where the aneurysm involved the internal carotid artery, four surgical procedures were performed: aneurysmectomy with end-to-end anastomosis in 30 (33.0%) cases, aneurysmectomy with vein graft interposition in 20 (22.0%) cases, aneurysmectomy with anastomosis between external and internal carotid artery in eight (8.8%) cases, and aneurysmectomy followed by arterial ligature in three cases. One case of external carotid artery aneurysm also was treated by aneurysmectomy and ligature. Aneurysm replacement with Dacron graft was performed in 29 (31.9%) cases where common carotid artery bifurcation was involved. Two (2.2%) patients died after the operation due to a stroke. They had ruptured internal carotid artery aneurysm treated by aneurysmectomy and ligature. Including these, a total of five (5.5%) postoperative strokes occurred. In two (2.2%) cases, transient cranial nerve injuries were found. Excluding the five patients who were lost to follow-up, 69 other surviving patients were followed from 2 months to 12 years (mean 5 years and 3 months). In this period, there were no new neurological events and all reconstructed arteries were patent. Three patients died more than 5 years after the operation, due to myocardial infarction. Aneurysms of the extracranial carotid arteries are rare vascular lesions that produce a high incidence of unfavorable neurological sequelae. Because of their varied etiology, location, and extension, different vascular procedures have to be used during repair of extracranial carotid artery aneurysms. In all of these procedures, an aneurysmectomy with arterial reconstruction is necessary.

Exposure of the cervical internal carotid artery: surgical steps to the cranial base and morphometric study

OBJECTIVE

Several studies have reported on approaches to increase exposure of the distal cervical internal carotid artery (ICA), but these studies have neither systematically addressed the anatomic aspects nor quantified the additional exposure of each maneuver. We describe surgical steps to expose the ICA region, quantify the additional exposure of each operative step, and discuss ways to minimize surgical morbidity.

METHODS

The ICA was exposed in 10 formalin-fixed cadaveric heads using the following four steps: 1) anterior sternocleidomastoid approach, 2) retroparotid dissection and division of the digastric muscle, 3) section of the styloid apparatus, and 4) mandibulotomy. After completion of each step, the most distal level of ICA exposure was marked with a hemoclip and segment lengths were measured between each clip.

RESULTS

Sectioning of the digastric muscle and sectioning of the styloid apparatus provided the most significant exposure of the ICA (14.15 and 15.08 mm, respectively) with minimal risks. Mandibulotomy added 10.20 mm in length and 20.65 degrees in width, but is a maneuver that must be weighed against the heightened risk of morbidity.

CONCLUSION

Surgical exposure of the distal cervical ICA is associated with relatively high morbidity that increases with higher levels of exposure. Staged maneuvers have been shown to increase ICA exposure, especially in our systematic approach. The number of steps required varies depending on the level of lesion. Complete understanding of the surgical anatomy is essential to minimize surgical morbidity and to develop surgical expertise.

SURGICAL MANAGEMENT OF EXTRACRANIAL INTERNAL CAROTID ANEURYSMS BY CERVICAL APPROACH

BACKGROUND

Extracranial internal carotid artery aneurysms (EICAA) are rare vascular problems with a great potential for lethal thromboembolic episodes.

METHODS

From 1994 to 2004, nine patients with EICAA, seven men and two women, were surgically treated for 10 aneurysms in our department. Aneurysm led to hemispheric symptoms in six cases (two hemispheric strokes and four hemispheric transient ischaemic attacks). The cause was fibrodysplasia in two cases, atherosclerosis in four cases, trauma in two cases and spontaneous dissection in two cases. All aneurysms were treated surgically by the cervical approach using shunting. Extended cervical approach was necessary in four patients with high-lying aneurysms. Nine aneurysms were totally resected and successful revascularization was carried out. Open aneurysmorrhaphy with vein patch angioplasty was carried out in one case of a saccular aneurysm.

RESULTS

There were no perioperative deaths or transient ischaemic attacks or strokes. Four patients developed cranial nerve deficits: one had hoarsness, two had partial facial paralysis (patients with extended cervical approach) and one had tongue deviation. These neurological symptoms were observed in large aneurysms (>4.5 cm) and disappeared within 14 months. No neurological complication was observed in a follow up that ranged from 6 months to 10 years.

CONCLUSIONS

Surgical repair of EICAA, especially with total resection and arterial reconstruction, is strongly recommended. Extended cervical approach has many technical difficulties but can allow treatment of high-lying aneurysms.

Covered stent treatment for traumatic cervical carotid artery aneurysms--two case reports

A 37-year-old man and a 23-year-old man with cervical carotid artery aneurysms were treated with covered stents. The covered stent was constructed from a Palmaz stent covered with an expanded polytetrafluoroethylene graft. Angiography showed the aneurysms had disappeared immediately after the procedure. Patency of the covered stents was confirmed at 18 and 34 months after intervention by three-dimensional computed tomography angiography. The covered stent allows relatively noninvasive reconstruction of the parent artery that immediately brings about complete thrombosis of the aneurysm. However, delivering the covered stent to the carotid artery may be difficult.

Aneurysms of the Carotid Artery

Carotid artery aneurysms are an uncommon but important problem. The available data suggests that, untreated, these aneurysms lead to neurologic symptoms from embolization. Pseudoaneurysms of the carotid artery result from injury or may be the long-term sequelae of a spontaneous carotid dissection. While open surgery has been the primary mode of treatment, these aneurysms are being treated more commonly with endovascular approaches. This trend is partly the result of the increasing experience with the endovascular treatment of carotid artery stenosis. The endovascular approach offers advantages in other situations where open access to the distal extent of the aneurysm is difficult or neck radiation leads to concerns about wound healing. This article outlines the etiology, new diagnostic modalities, and treatment of aneurysms of the carotid artery.

Possibility of middle meningeal artery-to-petrous internal carotid artery bypass: an anatomic study

The possibility of creating a middle meningeal artery (MMA)-to-petrous internal carotid artery (ICA) bypass was investigated in six cadavers (bilaterally). Such a procedure could be used to treat patients with high cervical vascular lesions and those with tumors of the infratemporal fossa invading the high cervical ICA. After a frontotemporal craniotomy, the foramen spinosum and foramen ovale were exposed extradurally. Immediately posterior to the foramen ovale and medial to the foramen spinosum, the petrous portion of the ICA was exposed with a diamond-tipped drill. The MMA was lifted from its groove, and a sufficient length was transected to perform a bypass with the petrous ICA medially. The mean width of the MMA at the site of anastomosis was 2.3 +/- 0.35 mm. The mean length of MMA from the foramen spinosum to the site of the anastomosis was 9.6 +/- 1.7 mm. Based on these measurements, width and length of MMA appear to be sufficient for a bypass with petrous ICA.

Bilateral spontaneous vertebral artery dissection: management during labor and vaginal delivery

We report the successful management of labor and delivery of a parturient with a history of spontaneous bilateral vertebral artery dissection. We also outline the reasons why the obstetric anesthetist should be aware of this condition as well as other cranio-cervical dissections.

Emergent endovascular treatment of a spontaneous internal carotid artery dissection with pseudoaneurysm

PURPOSE

To report the use of a coronary stent-graft for the endovascular treatment of a spontaneous internal carotid artery (ICA) dissection complicated by a large pseudoaneurysm.

CASE REPORT

A 68-year-old man presented to an outside hospital with complaints of headache, severe left-sided neck pain, fever, chills, and vomiting. Contrast-enhanced computed tomography revealed a large (3.5x3 cm) extracranial aneurysm of the left ICA. The patient was emergently transferred to our facility for endovascular treatment of the carotid aneurysm. Via a percutaneous access in the right common femoral artery, 2 Jostent coronary stent-grafts were deployed across the aneurysm with no evidence of a residual pseudoaneurysm. The patient was hemodynamically stable throughout the procedure. Duplex examination at 9 months revealed no evidence of a residual pseudoaneurysm, dissection, or endoleak.

CONCLUSIONS

Covered coronary stents may have a role in the treatment of spontaneous ICA dissection with pseudoaneurysm formation.

Cerebral revascularization

During the last 10 years, there has been a revival of interest in cerebral revascularization procedures. Not only have significant progressions in surgical techniques been published, the use of more advanced diagnostic methods has led to a widening of the indications for cerebral bypass surgery. The purpose of this review is to outline the current techniques for extracranial-to-intracranial (EC/IC) and intracranial-to-intracranial (IC/IC) bypass surgery, as well as to identify the current indications for revascularization procedures based on the available literature. The excimer laser-assisted non-occlusive anastomosis (ELANA) technique is described in more detail because we think that this technique almost completely eliminates the risk of cerebral ischemia due to the temporary vessel occlusion which is currently used in conventional anastomosis techniques.

"Malignant" carotid artery dissection

PURPOSE

Carotid artery dissection resulting in occlusion or severe narrowing and massive intracranial embolism can result in life-threatening hemispheric ischemia. Aggressive endovascular and microsurgical measures may be necessary to salvage life and minimize stroke morbidity in this extreme situation.

PATIENTS AND METHODS

We have treated two middle-aged women who presented within an hour of spontaneous cervical internal carotid artery (ICA) dissection causing hemiplegia, forced head and eye deviation, and declining consciousness. The first patient had a carotid occlusion through which a catheter could not be passed, so intracranial thrombolysis was achieved through a microcatheter navigated through the posterior circulation. Surgical intimectomy and thrombectomy of the dissected ICA was then carried out using an intraoperative Fogarty arterial embolectomy catheter passed up the dissected ICA, followed by endovascular stenting of the reopened cervical ICA. The second patient underwent intracranial microsurgical embolectomy and, after an unsuccessful attempt of stenting the dissected and severely narrowed cervical ICA, surgical reopening again with a Fogarty catheter. Both patients suffered basal ganglionic infarcts but most of the middle cerebral artery territories were preserved and the patients made satisfactory recoveries.

CONCLUSIONS

"Malignant" carotid artery dissection causing occlusion or near occlusion with intracranial embolism is an important cause of severe and life-threatening hemispheric ischemia. Treatment should include aggressive endovascular and microsurgical interventions when the hemisphere is at risk.

Unique case of pulsatile tinnitus

Tinnitus is a common symptom encountered by otolaryngologists. Pulsatile tinnitus is rare and can present a diagnostic challenge. Establishing a diagnosis is important, because pulsatile tinnitus may indicate serious intracranial or extracranial disease. A unique case of pulsatile tinnitus caused by cervical artery dissection is presented, along with the differential diagnosis and treatment.

Minimally invasive surgical exposure of the extreme high cervical internal carotid artery: anatomical study

The purpose of this study is to investigate a minimally invasive access to a high cervical lesion involving the internal carotid artery. Using 13 fixed cadaveric preparations, we sought to design a surgical approach that would cause minimal involvement of the surrounding structures and maximal exposure to the extreme high cervical area. This technique preserves the function and integrity of the mandible, sternocleidomastoid, posterior belly of digastric and styloid process muscles. The method uses retraction and mobilisation of those muscles, as well as decompression of the facial from the stylomastoid foramen. The internal carotid artery is exposed up to the entry point into the carotid canal. The cranial nerves IX, X, XI and XII are kept in sight up to the jugular foramen. This approach creates a wide corridor into the deep high cervical and inferior cranial base area and can be utilised for high cervical carotid lesions and tumours related to the artery.

The treatment of spontaneous carotid and vertebral artery dissections

Spontaneous dissections of the carotid and vertebral arteries in the neck are a common cause of stroke in young and middle-aged people. Moreover, they are increasingly recognized as the cause of a wide variety of other, more subtle, neurologic signs and symptoms. The cause of these arterial dissections largely remains unexplained but probably involves a combination of genetic and environmental factors. Magnetic resonance imaging has largely surpassed angiography as the imaging study of choice. The treatment of carotid and vertebral artery dissections is based on rather incomplete evidence. Anticoagulation with heparin followed by warfarin remains the treatment of choice in most major medical centers and is supported by the demonstration of emboli as the most common cause of stroke in these patients. The burgeoning interest in endovascular techniques has resulted in many patients being treated for carotid and vertebral artery dissections with percutaneous angioplasty and stent deployment. Although the treatment of dissections is generally well tolerated and the radiographic results are impressive, most dissections heal spontaneously and the associated aneurysms never rupture and rarely cause delayed ischemic symptoms. Surgical treatment of dissections, consisting of an in situ interposition graft or extracranial-intracranial bypass, is indicated only for those patients with persistent symptoms refractory to maximal medical therapy who are not candidates for endovascular treatment.

Surgical treatment of extracranial internal carotid artery aneurysms

PURPOSE

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). The cause was atherosclerosis (n = nine patients), dysplasia (n = 12 patients), trauma (n = three patients), and undetermined (n = one patient). The symptoms were focal in 15 cases (12 hemispheric, three ocular), nonfocal in three cases (trouble with balance and visual blurring), and glossopharyngeal nerve compression in one case. Six cases were asymptomatic, including three cases that were diagnosed during surveillance after ICA dissection. In nine cases, the upper limit of the EICA reached the base of the skull. A combined approach with an ear, nose, and throat surgeon allowed exposure and control of the ICA.

RESULTS

After operation, there were no deaths, one temporary stroke, two transient ischemic attacks, and 11 cranial nerve palsies (one with sequelae). The ICA was patent on the postoperative angiogram in all but one case. During follow-up (mean, 66 months), there were two deaths (myocardial infarction), one occurrence of focal epileptic seizure at 2 months, and one transient ischemic attack at 2 years. In December 1998, duplex scanning showed patency of the reconstructed ICA in all but one surviving patient.

CONCLUSION

Surgical reconstruction is a satisfactory therapeutic choice for EICA, even when located at the base of the skull.

Extracranial carotid artery aneurysms: Texas Heart Institute experience

BACKGROUND 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. All aneurysms were surgically explored, and all were repaired except two: a traumatic distal internal carotid artery aneurysm and an infected pseudoaneurysm in which the carotid artery was ligated.

RESULTS

Four deaths (three fatal strokes and one myocardial infarction) and two nonfatal strokes were directly attributed to a repaired ECA aneurysm (overall mortality/major stroke incidence, 9%); there was one minor stroke (incidence, 1.5%). The incidence of cranial nerve injury was 6% (four cases). During long-term follow-up (1.5 months-30 years; mean, 5.9 years), 19 patients died, mainly of cardiac causes (11 myocardial infarctions).

CONCLUSION

The potential risks of cerebral ischemia and rupture as well as the satisfactory long-term results achieved with surgery strongly argue in favor of surgical treatment of ECA aneurysms.

Usefulness of the C1 transverse process as a reference guide in the dissection of the upper lateral neck

In this investigation we dissected 3 cadavers with the lateral cervical approach to assess the usefulness of the transverse process of the atlas (TPA) as a reference guide in the upper lateral neck. Our results indicate that all the important structures in this space can be identified systematically. Lateral to the TPA sits the posterior belly of the digastric muscle, the stylohyoid muscle, and the occipital artery. Anterior to the TPA, the styloid process can be exposed. The internal jugular vein and cranial nerves X, XI, and XII sit between the styloid process and the TPA. Superior to the TPA, tracing the carotid sheath upward, the carotid canal and jugular foramen can be reached. Anteroinferior to the jugular foramen, the hypoglossal nerve emerges from the cranial cavity through the hypoglossal canal. Posterior to the TPA, the suboccipital triangle can be recognized. Within the triangle, the vertebral artery and its accompanying venous complex can be identified.

Traumatic aneurysms and arteriovenous fistulas of the extracranial vessels in war injuries

BACKGROUND

Extracranial vessel injuries are potentially devastating complications of penetrating head and neck wounds associated with war conflicts. These vasculopathies may be occlusive or they may lead to formation of traumatic aneurysms (TA) and arteriovenous fistulae (AVF). Even though these penetrating injuries are usually clinically silent and often appear only as small superficial wounds, they may lead to catastrophic hemorrhage or vascular insult. In this study, we attempted to elucidate signs, symptoms and circumstances present in these victims who are at risk of harboring an occult vasculopathy, excluding the occlusive ones and concentrating primarily on TAs and AVFs.

MATERIALS AND METHODS

In a prospective study conducted during 8 years of war between Iran and Iraq, we encountered 13 cases of traumatic vasculopathies of the extracranial carotid and vertebral arteries. The type and number of injuries were: carotid-jugular fistula (CJF) 3, carotid trunk or branch aneurysm (CA) 2, superficial temporal artery aneurysm (STA) 3, vertebral artery aneurysm (VA) 2, vertebral arteriovenous fistula (VAVF) 1, ophthalmic artery aneurysm (Oph. An.) 1, and lingual artery aneurysm (Lin. An.) 1. Angiography was performed between the 5th and 30th day after the injury and surgical intervention was performed in all cases.

RESULTS

The Glasgow outcome scale (GOS) score was 13-15 in all victims at the time of discharge from the base hospital without any additional neurological deficit. The follow-up period varied from 5 to 8 years in all cases in whom no further morbidity or mortality occurred. Single photon emission computed tomography was the noninvasive tool used for measurement of cerebral blood flow in the cases in which a major vessel ligation was performed; no remarkable change in cerebral blood flow was noted.

CONCLUSION

Early recognition of stigmas suggesting possible formation of extracranial traumatic vasculopathies such as TAs or AVFs in the difficult situation of war frontier hospitals should be highlighted for attending physicians or younger neurosurgeons. Performing angiography promptly in suspected cases can pick up such traumatic vascular lesions earlier. Using simpler surgical techniques in situations in which more sophisticated endovascular equipment is unavailable can be life-saving for these usually young victims.

Cervicocerebral artery dissections

OBJECTIVE

To determine the aetiology, frequency, presentation, and outcome of blunt cervicocerebral arterial dissection presentations.

PATIENTS AND METHODS

Cases were retrospectively identified through the stroke registers at Royal Melbourne Hospital (a tertiary teaching hospital) and Geelong Hospital (a regional referral centre). Medical notes were then reviewed.

RESULTS

A total of 18 cases were identified, with ages ranging from 28 to 53 years. Fifty five per cent of the injuries sustained were to the internal carotid artery and 45% to the vertebral artery. The majority of the injuries were either spontaneous or associated with trivial forces. Other causes included motor vehicle accidents, falls, and cervical manipulations. Fifty five per cent of patients complained of significant neck pain before presentation. Most patients had delayed presentations, with only 39% presenting on the day of the incident. Seventy eight per cent presented with a neurological deficit. Initial computed tomography was normal in 71% of patients. The majority of patients were managed with anticoagulation, and had minimal functional deficit on discharge. Other treatment modalities included surgery (one patient) and thrombolysis (two patients). One patient was managed conservatively.

CONCLUSIONS

The incidence of blunt cervicocerebral arterial dissection is unknown; however it is an uncommon diagnosis. The most common presentation is that of a delayed neurological event. Initial brain computed tomography is usually normal. Minimal adverse outcomes at discharge were noted in patients treated with anticoagulation only.

Endovascular occlusion of a carotid pseudoaneurysm complicating deep neck space infection in a child. Case report

Pseudoaneurysm formation of the cervical internal carotid artery (ICA) is a rare, potentially lethal complication of deep neck space infection. This entity typically occurs following otolaryngological or upper respiratory tract infection. The pseudoaneurysm is heralded by a pulsatile neck mass, Homer's syndrome, lower cranial neuropathies, and/or hemorrhage that may be massive. The recommended treatment includes prompt arterial ligation. The authors present a case of pseudoaneurysm of the cervical ICA complicating a deep neck space infection. A parapharyngeal Staphylococcus aureus abscess developed in a previously healthy 6-year-old girl after she experienced pharyngitis. The abscess was drained via an intraoral approach. On postoperative Day 3, the patient developed a pulsatile neck mass, lethargy, ipsilateral Horner's syndrome, and hemoptysis, which resulted in hemorrhagic shock. Treatment included emergency endovascular occlusion of the cervical ICA and postembolization antibiotic treatment for 6 weeks. The patient has made an uneventful recovery as of her 18-month follow-up evaluation. Conclusions drawn.from this experience and a review of the literature include the following: 1) mycotic pseudoaneurysms of the carotid arteries have a typical clinical presentation that should enable timely recognition; 2) these lesions occur more commonly in children than in adults; 3) angiography with a view to performing endovascular occlusion should be undertaken promptly; and 4) endovascular occlusion of the pseudoaneurysm is a viable treatment option.