Bilateral External Carotid Research Articles

English

  High-volume intra- and extra cranial artery bypass surgery has been widely used, but it remains a difficult technique for most of surgeons. The objective of this study is to explore a training mode and platform. Six healthy dogs were divided into three groups at random. Twelve high-volume common carotid-external carotid bypasses were operated on both sides of six dogs (n=12). Digital subtraction angiography (DSA) and color Doppler sonography were taken to measure the hemodynamic parameters of grafts one week (n=4), four weeks (n=4) and 24 weeks (n=4) after the operations. The grafts were taken out for histopathological examination 24 weeks after the operations. The high-volume common carotid-external carotid bypass model (n=12) was successfully established in six dogs under microscope. Post-operative DSA in Week 1 (n=4), Week 4 (n=4) and Week 24 (n=4) showed bilateral external carotid blood flow was supplied by contralateral common carotid grafts. Both ends and the whole grafts were patent. Color Doppler sonography showed clearly that the blood flow volume of grafts was higher than 90 ml/min. Histopathological examination taken 24 weeks after the operations showed intimal hyperplasia of grafts. Dog model of high-volume common carotid-external carotid bypass has the advantages of similar material, high volume, similar blood pressure, feasible operation and high patent rate compared to the traditional microsurgery model, making it a better simulation training platform which is closer to the real surgical procedure for surgeons willing to master the technique of high-volume bypass operation.   Key words: Dog, animal model, bypass, high-volume, vascular anastomosis.

Analysis of passive motion of para- and retropharyngeal structures during swallowing using dynamic magnetic resonance imaging.

The purpose of this study was to analyze passive motion of the para- and retropharyngeal space (PRS) during swallowing using dynamic magnetic resonance imaging (MRI). We conducted a preliminary study involving 30 healthy volunteers who underwent dynamic MRI. Consecutive MRI axial images were obtained by examining the plane parallel to the hard palate at the level of the anterior inferior corner of C2. Anterior displacement of the posterior pharyngeal wall (PPW) was measured as a motion index of pharyngeal contraction. The displacement and internal angle of the bilateral external and internal carotid arteries (ECA and ICA) and the bilateral centroids of the PRS area, as well as the increase in PRS area, were calculated at rest and at maximum pharyngeal contraction. In most participants, the bilateral ECA, ICA, and centroids were anterointernally displaced by pharyngeal contraction. The normalized ECA displacement (r = 0.64, r (2) = 0.41), normalized ICA displacement (r = 0.60, r (2) = 0.37), and normalized centroid displacement (r = 0.43, r (2) = 0.19) were more than moderately positively correlated with the normalized PPW displacement. The normalized PRS area increase (r = 0.35, r (2) = 0.12) was weakly positively correlated with the normalized PPW displacement. These results revealed that PRS area increased as the ECA and ICA were drawn anterointernally via its passive motion by pharyngeal contraction.

Reversible cerebral vasoconstriction syndrome with involvement of external carotid artery branches.

A 44-year-old woman presented with recurrent episodes of thunderclap headache. Neurological examination and computed tomography brain imaging were unremarkable. Cerebrospinal fluid findings were consistent with subarachnoid hemorrhage. Computed tomography angiography of the circle of Willis showed multiple areas of segmental vasoconstriction. This finding was confirmed on cerebral catheter angiography, with segmental vasoconstriction involving bilateral internal carotid, posterior cerebral, and external carotid branches. No aneurysm or other vascular abnormality was identified. She received treatment with nimodipine. A selective serotonin reuptake inhibitor, started 4 weeks earlier, was discontinued. Follow-up angiography after 3 months demonstrated complete resolution of the segmental vasoconstriction, confirming the diagnosis of reversible cerebral vasoconstriction syndrome (RCVS). She remained headache free at follow-up. To our knowledge, external carotid artery branch involvement in RCVS has been described only in one previous occasion.

Temporary clamping of bilateral external carotid arteries for surgical excision of a complex dural arteriovenous fistula

Background:Some complex dural arteriovenous fistulas (DAVFs) are lesions that typically have numerous arterial feeders. Surgery, including resection of fistulas or skeletonization of the diseased sinus, is still one of the important treatments for these lesions. However, major blood loss is usually encountered during craniotomy because of abundant arterial feeders from the scalp and transosseous vessels. We present a novel approach for obliteration of the fistulas with less blood loss.Methods:Our first case was a 52-year-old male who suffered from syncope and seizure. Cerebral digital subtraction angiography (DSA) revealed complex DAVFs with numerous arterial feeders from bilateral external carotid arteries (ECAs) and drainage into the superior sagittal sinus with cerebral venous reflux. The second case was a 48-year-old male presenting with chronic headache. His DSA also showed complex DAVFs along the superior sagittal sinus with cerebral venous reflux. In both cases, we performed the surgical procedure to obliterate the pathological fistulas after temporary clamping of bilateral ECAs and noted less blood loss than in the conventional surgery.Results:The follow-up DSA showed successful obliteration of the complex DAVFs on the first case and partial improvement on the second case followed by transarterial embolization (TAE). The symptoms of the both patients were relieved after surgery with good recovery.Conclusion:Temporary clamping of bilateral ECAs can improve the safety and ease the surgical excision for complex DAVFs. By using this technique, neurosurgeons can deal with aggressive DAVFs more confidently and calmly.

Radiological Diagnosis and Management of Epistaxis

The majority of episodes of spontaneous posterior epistaxis treated with embolisation are idiopathic in nature. The angiographic findings are typically normal. Specific angiographic signs are rare and may include the following: a tumour blush, telangiectasia, aneurysm, and/or extravasation. Selective internal carotid artery (ICA) angiography may show rare causes of epistaxis, such as traumatic or mycotic aneurysms, which require different treatment approaches. Complete bilateral selective external and internal carotid angiograms are essential to evaluation. The images should be analysed for detection of central retinal blush in the external carotid artery (ECA) and anastomoses between the branches of the ECA and ICA. Monocular blindness and stroke are two of the most severe complications. Embolisation aims to decrease flow to the bleeding nasal mucosa while avoiding necrosis of the nasal skin and palate mucosa. Embolisation is routinely performed with a microcatheter positioned in the internal maxillary artery distal to the origin of the meningeal arteries. A guiding catheter should be placed in the proximal portion of the ECA to avoid vasospasm. Embolisation with microparticles is halted when the peripheral branches of the sphenopalatine artery are occluded. The use of coils is not recommended because recurrent epistaxis may occur due to proximal embolization; moreover, the option of repeat distal embolisation is lost. The success rate of embolisation therapy (accounting for late recurrence of bleeding) varies between 71 and 94 %. Results from endoscopic surgery are quite comparable. When epistaxis is refractory to nasal packing or endoscopic surgery, embolisation is the treatment of choice in some centres.

A Rare Case of Spontaneous Revascularization in a Patient withSignificant Carotid Artery Disease

Severe common and external carotid artery disease is a rare entity, which generallyoccurs in patients with advanced atherosclerosis. This report describes the case ofan 83-year-old woman, who was referred to our hospital due to dizziness, headachesand loss of balance, permanent amaurosis of the right eye, decreased visual acuityof the left eye and bilateral hypoacusis at high frequencies.A color Doppler ultrasound of the neck vessels revealed significant bilateralcommon and external carotid artery and right carotid bulb disease, with a reverserevascularization circuit through bilateral external carotid arteries, which alsoshowed significant stenosis in their respective origins.

Preoperative angiography and external carotid artery embolization of juvenile nasopharyngeal angiofibromas in a tertiary referral paediatric centre

To evaluate the relationship between intraoperative blood loss and juvenile nasopharyngeal angiofibroma (JNA) vascular supply and tumour stage in patients who underwent superselective external carotid artery (ECA) embolization. This series is unique in that all embolizations were performed by dedicated paediatric interventional radiologists at a tertiary referral paediatric centre. Seventeen male patients treated from January 2002 to August 2009 underwent preoperative angiography and embolization using polyvinyl alcohol (PVA) particles. Tumours were graded using three different staging systems based on preoperative imaging and correlated to surgical blood loss. All patients underwent bilateral internal and external carotid angiography, with embolization of ECA tumour supply via microcatheter delivery of PVA particles. Particle size ranged from 150-500μm with a mean size of 250-355μm. Surgical resection was performed with either endoscopic or open techniques within 24h and intraoperative blood loss was reported. Seven lesions were supplied strictly by the ECA circulation and had mean surgical blood loss of 336ml. Twelve lesions had both ECA and internal carotid artery (ICA) supply and had mean surgical blood loss of 842ml. The difference in blood loss in these two groups was statistically significant (p=0.03). There was no case of inadvertent intracranial or ophthalmic embolization. There were statistically significant correlations between estimated surgical blood loss and the Andrews (p=0.008), Radkowski (p=0.015), and University of Pittsburgh Medical Center (UPMC; p=0.015) preoperative tumour staging systems, respectively. Preoperative embolization of JNA tumours can be safely performed without neurological complications. The present study identified a statistically significant difference in intraoperative blood loss between those lesions with a purely ECA vascular supply and a combination of ECA and ICA vascular supply. Angiography is helpful in delineating ICA supply and can help guide surgical planning.

Blind endovascular catheterization and direct access of an occluded superior ophthalmic vein for treatment of carotid cavernous fistula

We describe a case of an elderly patient who presented with right-sided ophthalmoplegia, proptosis, chemosis, and increased intraocular pressure. An angiogram showed feeding vessels from the bilateral internal and external...

Primary malignant lymphoma of the cranial vault with extra- and intracranial extension.

Bone involvement is a common finding in many types of lymphomas, particularly in advanced stages. However, cranial vault affliction has been regarded as an exceedingly rare presentation. Here, we report the case of a patient with cranial vault lymphoma who presented with a scalp mass. An 81-year-old woman presented with a gradually growing and non-painful frontal scalp mass that she noticed one month before admission. It was a flatly elevated, round mass measuring about 6×4×4 cm. Computed tomography and magnetic resonance imaging of the brain revealed a contrast-enhancing intracranial extradural mass at the counter-location of the scalp mass. The superior sagittal sinus was involved at the tumor site. Cerebral angiography showed that the tumor feeding vessels originated from the bilateral external carotid arteries. An operation was performed and the tumors were removed together with the involved bone. The pathologic diagnosis was malignant diffuse large B-cell type lymphoma. The patient was transferred to the Hemato-Oncology department for chemotherapy. Primary lymphoma of the cranial vault with scalp mass is very rare but it should be considered in the differential diagnosis of scalp masses. Although the results of reported cases are variable, the combination of surgery, radiation, and chemotherapy appears to offer favorable outcomes.

Progressive AVM Thrombosis after Onyx Embolization with Angiographic Cure

Intracranial arteriovenous malformations (AVMs) have a cumulative risk of hemorrhage and refractory seizures. Pre-surgical Onyx embolization of cerebral AVMs improves clinical outcome. A 45-year-old man with a history of seizures was diagnosed with a Spetzler-Martin grade 4 AVM in the right occipital lobe. As per initial assessment, three to four sessions were required for adequate devascularization of the AVM before offering either surgery or gamma knife treatment. We achieved 10% and 70% devascularization in the first and second stage Onyx18 embolization respectively. Subsequent bilateral internal carotid, external carotid, vertebral and right posterior cerebral artery superselective angiography performed six weeks after the second stage of embolization demonstrated unexpected complete angiographic cure of the AVM.

Evidence for a Strong Genetic Influence on Carotid Plaque Characteristics

Few family studies reported moderate genetic impact on the presence and scores of carotid plaques. However, the heritability of carotid plaque characteristics remains still unclear. Twin studies more reliably estimate the relative contribution of genes to these traits in contrast to family study design. One hundred ninety-two monozygotic and 83 dizygotic adult twin pairs (age 49±15 years) from Italy, Hungary, and the United States underwent B-mode and color Doppler ultrasound of bilateral common, internal, and external carotid arteries. Age-, sex-, and country-adjusted heritability was 78% for the presence of carotid plaque (95% CI, 55%-90%), 74% for plaque echogenicity (hypoechoic, hyperechoic, or mixed; 95% CI, 38%-87%), 69% for plaque size (area in mm2 in longitudinal plane; <or>50 percentile; 95% CI, 16%-86%), 74% for plaque sidedness (unilateral or bilateral; 95% CI, 25%-90%), 74% for plaque numerosity (95% CI, 26%-86%), 68% (95% CI, 40%-84%), and 66% (95% CI, 32%-90%) for the presence of plaque in carotid bulbs and proximal internal carotid arteries. No role of shared environmental factors was found. Unique environmental factors were responsible for the remaining variance (22%-34%). Controlling for relevant covariates did not change the results significantly. The heritability of ultrasound characteristics of carotid plaque is high. Unshared environmental effects account for a modest portion of the variance. Our findings should stimulate the search for genes responsible for these traits.

Pontine venous congestion due to dural arteriovenous fistula of the cavernous sinus: Case report and review of the literature

Background:We report herein a case of cavernous sinus (CS)-dural arteriovenous fistula (DAVF) with brainstem venous congestion that was successfully treated by transarterial embolization, followed by radiotherapy.Case Description:An 80-year-old woman presented with right eye chemosis and left hemiparesis. T2-weighted magnetic resonance imaging showed hyperintensity of the pons. Diagnostic cerebral angiography demonstrated CS-DAVF draining into the right superior orbital vein and petrosal vein, and fed by bilateral internal and external carotid arteries. Transarterial embolization was performed and followed by radiotherapy, resulting in resolution of the pontine lesion and neurological and ophthalmological symptoms within 5 months.Conclusions:We also review the literature regarding therapy for CS-DAVF with brainstem venous congestion. Once CS-DAVF with venous congestion of the brainstem has been definitively diagnosed, immediate therapy is warranted. Treatment with transarterial embolization followed by radiation may be an important option for elderly patients when transvenous or transarterial embolization is not an option.

Concurrent Stenoocclusive Disease of Intracranial and Extracranial Arteries in a Patient with Polycythemia Vera

Moyamoya disease is a stenoocclusive disease involving the intracranial carotid and proximal middle cerebral arteries. There are rarely any additional extracranial stenoses occurring concurrently with moyamoya. The pathophysiology of moyamoya remains obscure, but hematologic disorders, notably sickle-cell anemia, have been associated in some cases. We describe the novel case of polycythemia vera associated with severe steno-occlusive disease of both intracranial and extracranial large arteries. A 47-year-old woman with polycythemia vera had multiple transient ischemic attacks, and noninvasive vessel imaging revealed steno-occlusive disease of bilateral supraclinoid internal carotid arteries with moyamoya-type collaterals, proximal left subclavian artery, right vertebral artery origin, bilateral renal arteries, superior mesenteric artery, and right common iliac artery. Laboratory workup for systemic vasculitis was negative. She required bilateral direct external carotid to internal carotid bypass procedures and percutaneous balloon angioplasty of her right VA origin stenosis. This case suggests that hematologic disorders can lead to vessel stenoses and occlusion. The pathophysiology may be due to a prothrombotic state leading to repeated endothelial injury, resultant intimal hyperplasia, and progressive steno-occlusion.

Facial Composite Tissue Allograft

Despite complex facial anatomy, transplantation of soft tissues of the entire face, including the maxilla and mandibular segment anterior to the masseter muscle insertion, can be safely performed based on facial vessels alone. Inclusion of hair-bearing scalp requires dissection of the superficial temporal vessels. Unlike other groups, we advocate for supercharging dissected superficial temporal vessels in the preauricular area avoiding difficult dissections in the depth of external auditory canal that presents significant challenges associated with lengthy dissection and bleeding. Neurorrhaphy at the trunk of the facial nerve leads to less targeted postoperative reinnervation, with potential for synkinesis, and whenever possible, individual peripheral facial nerve branches should be reconnected. Adequate planning for integration of the facial allograft requires both complete sensory and motor nerve connection and should be part of each operation. Bilateral external carotid anastomosis may cause a variety of functional problems including oropharyngeal dysfunction and ocular ischemia and hence is not recommended.

Tongue necrosis as an unusual presentation of carotid artery stenosis

A 57-year-old man with premature coronary artery disease presented to the emergency department with left facial pain, numbness, and tongue swelling. The patient was found to have significant tongue necrosis, and subsequent arteriography demonstrated carotid bifurcation stenosis with embolization to the left lingual artery. The patient was successfully treated with debridement of his tongue and left carotid endarterectomy.

Selective regional perfusion of the bilateral external carotid arteries with pegylated liposomal doxorubicin and melphalan to treat metastatic malignant melanoma of the scalp

We present the case of a 79-year-old patient with extensive metastatic malignant melanoma (MM) of the scalp. Cutaneous MM of the head and neck often presents a therapeutic challenge. Radical surgical procedures and conventional chemotherapy are often unfeasible and contraindicated because of the difficult anatomy, the extent of the tumour process, and systemic toxicity. In our patient, selective intra-arterial perfusion with pegylated liposomal doxorubicin (PLD) and melphalan was performed after catheterization of both bilateral external carotid arteries with an arterial port system. PLD 4.5 mg/m(2) and melphalan (1.35 mg/m(2), followed by 2.7 mg/m(2) after reaching tolerance) were given as short-term infusions at two-weekly intervals into the right and left external carotid arteries, respectively. After eight applications with tolerable side-effects, no MM cells were detected; however, infiltrates of lymphocytes and melanophages were seen. This case suggests that intra-arterial chemotherapy may be a useful treatment for metastatic melanoma of the scalp.

The treatment of a dural carotid cavernous fistula (CCF) using Onyx via a transorbital approach: a technical note

We report the successful case of embolisation of a Barrow D (White et al. in Am J Neuroradiol 28:1415-1417, 2007) dural carotid cavernous fistula (CCF) with bilateral external carotid artery and internal carotid arterial supply, using a direct percutaneous transorbital approach with the embolic agent Onyx. In particular, we highlight the properties of Onyx which make it suitable to treat the multi-compartmental nature of CCFs. The patient developed transient complications which may be related to the volume of embolic agent used, and we discuss this point further. This is still a developing technique, and we present our case as a technical note to aid those contemplating embolisation via a transorbital approach with Onyx.

Combined Surgical and Endovascular Approach to a Complex Dural Arteriovenous Fistula Involving the Superior Sagittal Sinus and Torcula

A complex dural arteriovenous fistula (dAVF) may require complex treatment strategies to achieve successful obliteration. We describe a combined open surgical and endovascular approach to a dAVF involving the superior sagittal sinus (SS) and torcula. A 68-year-old male with Factor V Leiden mutation presented with altered mental status from venous hypertension secondary to a complex, high-flow Borden III dAVF with internal carotid and bilateral external carotid artery feeders draining into the SS and torcula. Because the venous channel to the recipient SS at the point of convergence of the AV shunting was not accessible transfemorally due to venous stenosis, a surgical strategy using a midline burrhole for direct catheterization of the SS was devised. A balloon was inflated in the sinus during arterial embolization. This technique was effective in achieving embolization of multiple arterial feeders via a single vessel injection. Covered Atrium iCasts were introduced in a telescoping fashion after angioplasty of the posterior SS-torcular junction in an attempt to functionally occlude further AV shunting. Postembolization angiography revealed greatly diminished AV shunting with improved intracranial transit time and retrograde cortical venous drainage. The patient was maintained on anticoagulation and made a complete recovery following the intervention; however, he subsequently deteriorated acutely, and died on postprocedure day 4. This case illustrates the difficulties associated with treating a complex AVF, describes a temporizing solution, and reports a potential complication from placing a covered stent in the SS.

E-038 Utility of Dyna CT in the evaluation and management of cranial and skull base arteriovenous fistulas

IntroductionIntracranial dural arteriovenous fistulas (dAVFs) are comprised of pathologic, dural based shunts and account for 10–15% of all intracranial arteriovenous malformations. These lesions have complex anatomy that is best studied...

Cognitive dysfunction induced by chronic cerebral hypoperfusion in a rat model associated with arteriovenous malformations

The relationship between chronic cerebral hypoperfusion and cognitive function has not been completely delineated. In the present studies, we developed an experimental model associated with arteriovenous malformation to investigate the effects of chronic cerebral hypoperfusion on cognitive function and neuropathological changes. The rat model was established by creating a fistula through an end-to-side anastomosis between the right distal external jugular vein and the ipsilateral common carotid artery, followed by ligation of the left vein draining the transverse sinus and bilateral external carotid arteries. Age-matched rats comprised a control group. Three months after surgery, cognitive functions were evaluated by the Morris water maze and hippocampal long-term potentiation (LTP). Neuropathological changes were examined using light and electron microscopic techniques. We found that both learning capacity and spatial memory were significantly impaired in rats with chronic cerebral hypoperfusion concomitant with LTP inhibition and neurodegeneration in the hippocampal CA1 region of model rats compared with control rats. In addition, model rats showed a decrease at the protein level of cyclic AMP response element binding (CREB) phosphorylation in hippocampal tissues. Therefore, cognitive impairment caused by chronic cerebral hypoperfusion associated with arteriovenous malformations may be partially explained by the neurodegeneration and reduction of CREB phosphorylation in rat hippocampus.