Carotid Artery System Research Articles

Carotid cavernous fistula: ophthalmological implications.

Carotid cavernous fistula (CCF) is an abnormal communication between the cavernous sinus and the carotid arterial system. A CCF can be due to a direct connection between the cavernous segment of the internal carotid artery and the cavernous sinus, or a communication between the cavernous sinus, and one or more meningeal branches of the internal carotid artery, external carotid artery or both. These fistulas may be divided into spontaneous or traumatic in relation to cause and direct or dural in relation to angiographic findings. The dural fistulas usually have low rates of arterial blood flow and may be difficult to diagnose without angiography. Patients with CCF may initially present to an ophthalmologist with decreased vision, conjunctival chemosis, external ophthalmoplegia and proptosis. Patients with CCF may have predisposing causes, which need to be elicited. Radiological features may be helpful in confirming the diagnosis and determining possible intervention. Patients with any associated visual impairment or ocular conditions, such as glaucoma, need to be identified and treated. Based on patient's signs and symptoms, timely intervention is mandatory to prevent morbidity or mortality. The conventional treatments include carotid ligation and embolization, with minimal significant morbidity or mortality. Ophthalmologist may be the first physician to encounter a patient with clinical manifestations of CCF, and this review article should help in understanding the clinical features of CCF, current diagnostic approach, usefulness of the available imaging modalities, possible modes of treatment and expected outcome.

A dual-layer transducer array for 3-D rectilinear imaging.

Very large element counts (16,000-65,000) are required for 2-D arrays for 3-D rectilinear imaging. The difficulties in fabricating and interconnecting 2-D arrays with a large number of elements (>5,000) have limited the development of suitable transducers for 3-D rectilinear imaging. In this paper, we propose an alternative solution to this problem by using a dual-layer transducer array design. This design consists of 2 perpendicular 1-D arrays for clinical 3-D imaging of targets near the transducer. These targets include the breast, carotid artery, and musculoskeletal system. This transducer design reduces the fabrication complexity and the channel count, making 3-D rectilinear imaging more realizable. With this design, an effective N x N 2-D array can be developed using only N transmitters and N receivers. This benefit becomes very significant when N becomes greater than 128, for example. To demonstrate feasibility, we constructed a 4 x 4 cm prototype dual-layer array. The transmit array uses diced PZT-5H elements, and the receive array is a single sheet of undiced P[VDF-TrFE] copolymer. The receive elements are defined by the copper traces on the flexible interconnect circuit. The measured -6 dB fractional bandwidth was 80% with a center frequency of 4.8 MHz. At 5 MHz, the nearest neighbor crosstalk of the PZT array and PVDF array was -30.4 +/- 3.1 dB and -28.8 +/- 3.7 dB, respectively. This dual-layer transducer was interfaced with an Ultrasonix Sonix RP system, and a synthetic aperture 3-D data set was acquired. We then performed offline 3-D beamforming to obtain volumes of nylon wire targets. The theoretical lateral beamwidth was 0.52 mm compared with measured beamwidths of 0.65 mm and 0.67 mm in azimuth and elevation, respectively. Then, 3-D images of an 8 mm diameter anechoic cyst phantom were also acquired.

REVASCULARIZATION OF SYMPTOMATIC SUBACUTE CEREBROVASCULAR OCCLUSIONS WITH A SELF-EXPANDING INTRACRANIAL STENT SYSTEM

In some patients, collateral circulation may preserve the viability of brain parenchyma distal to an intracranial arterial occlusion for hours or days after the presenting event. These patients may be good candidates for revascularization, even when they present outside of the accepted 6-hour time window for stroke intervention. Three patients were revascularized with the Wingspan stent system (Boston Scientific/Target, Fremont, CA) after presenting with subacute occlusions of intracranial arteries and progressive ischemic symptoms despite maximal medical therapy. All pre- and postprocedural imaging data and clinical records were reviewed. Three patients (mean age, 64 years; 2 women, 1 man) presented with symptomatic intracranial occlusions of the internal carotid artery (n = 2) and vertebrobasilar system (n = 1). All 3 patients presented more than 6 hours after symptom onset, and no intravenous or intra-arterial thrombolysis had been instituted. In all cases, despite supportive medical therapy (anticoagulation and antiplatelet therapy and induced hypertension), the patients continued to demonstrate progressive ischemia, both clinically and on diffusion magnetic resonance imaging. All patients were successfully revascularized without periprocedural complications and improved clinically after revascularization. In selected patients, symptomatic subacute occlusions of intracranial arteries may be revascularized using the Wingspan stent system.

The Helical Arcade

Survival of the ear based on a single vascular pedicle has been previously documented. The anatomic basis for this survival remains incompletely described. In the 3 clinical cases of inferior-to-superior near-total ear avulsion presented herein, the authors have observed that the ear can survive based on a narrow pedicle along the helical root. In an anatomic study to further investigate the relevant vascular anatomy, the common carotid artery system of 6 fresh human cadaver specimens was injected with latex. The superficial temporal artery and its branches located at the helical root were examined. This anatomic study showed that the upper auricular branch of the superficial temporal artery continues into the ear as the helical artery supplies an arterial arcade, which we have termed the helical arcade. This arcade seems to allow for communication between the anterior and posterior arterial systems of the ear and allows the helical artery to provide sufficient arterial supply to the entire ear.

内頚動脈系非分岐部動脈瘤の治療

We experienced 5 cases of nonbranching site aneurysms arising from the internal carotid artery system in the past 5 years. Two cases were successfully treated with neck clipping and 2 cases were treated with trapping. Wrapping by gauze and fibrin glue was used in 1 unruptured case. The outcome was good in all cases (mRS 0-2). However, non-branching site aneurysms have fragile walls, the neck is not clearly defined and postoperative rebleeding can easily occur. We believe the sacrifice of a normal parent artery is necessary to prevent re-bleeding. For this reason, we believe interception of the parent artery should always be considered to prevent postoperative rebleeding. When parent artery interception is of concern regarding postoperative ischemic events, a high-flow EC-IC bypass may be needed. On the other hand, the issue of separation of the neck is possible at all sides and the possibility of clipping strangling part of the parent artery also exists.

Carotid Ultrasound in One, Two and Three Dimensions

Ultrasound measurements of the carotid wall are widely used surrogate markers for atherosclerosis with the intima-media thickness (IMT) being the most commonly measured variable. However, ultrasound has recently defined carotid artery wall structures in higher spatial dimensions, such as total area of carotid plaques (TPA) and total volume of carotid plaques (TPV). It is possible that IMT, TPA and TPV measure different aspects of the atherosclerotic process and thus have different clinical implications. IMT, TPA and TPV have never been correlated in the same individuals. We had a unique dataset in which IMT, TPA and TPV were measured concurrently in 272 subjects. We evaluated the left and right carotid arterial systems in each subject as independent variables and performed three pairwise correlation analyses between IMT and transformed TPA and TPV from the 544 carotid arterial systems. We found pairwise correlations between IMT and square root TPA, IMT and cubic root TPV and square root TPA and cubic root TPV; these correlation coefficients were 0.667, 0.586 and 0.963, respectively (all P<0.0001). However, correlation graphs showed marked scatter of individual data points. Thus, IMT was only moderately well correlated with TPA and TPV, but TPA and TPV were very strongly correlated with each other. This suggests that IMT is less related to TPA and TPV than they are to each other and could reflect somewhat different aspects of atherosclerosis. Furthermore, the high correlation between TPA and TPV suggests that both might not need to be measured together in future analyses.

Ageing Affects the Accuracy of Duplex Ultrasonography in Grading Carotid Artery Stenosis

Background: Duplex ultrasonography is frequently used to select patients who are eligible for carotid endarterectomy by using local blood flow velocities to quantify the degree of internal carotid artery stenosis. However, ageing affects flow velocities and might hence influence the accuracy of duplex ultrasonography, as explored in the present study. Methods: We determined peak-systolic (PSV) and end-diastolic (EDV) blood flow velocities in the common carotid artery (CCA) and internal carotid artery (ICA) in the absence of atherosclerosis and correlated these with age. The established correlation was applied to measurements in the ICA with visualised atherosclerosis to evaluate whether an age-related change in blood flow velocities modified stenosis grading. Results: In 465 arteries without atherosclerosis, PSV declined linearly in both the CCA (r = –0.55) and ICA (r = –0.44). The EDV decreased linearly in the CCA and ICA (r = –0.61 and r = –0.56, respectively). In 774 internal carotid arteries with atherosclerosis present, the use of an age-dependent reference increased the estimated degree of stenosis in 3 young subjects. The stenosis grade was reduced in 11 older subjects, mainly in symptomatic arteries. Conclusions: Blood flow velocities in the carotid artery system decrease continuously with increasing age. This may affect the estimated degree of internal carotid artery stenosis in the elderly.

Factors analysis and unstabe plaques of carotid atherosclerosis in ischemic cerebrovascular patients

目的 探讨缺血性脑血管病患者颈动脉粥样硬化斑块不稳定性的相关因素.方法 应用彩色多普勒超声对132例颈动脉系统缺血性脑血管病患者进行颈动脉检查,发现斑块者根据超声表现分型,判断其稳定性;分析患者颈动脉斑块不稳定性与高血压、糖尿病、高脂血症及吸烟史的关系.结果 颈动脉粥样硬化斑块最常见于颈动脉分叉处(56.99%),其次为颈总动脉主干(23.12%);有吸烟、高血压、糖尿病史者不稳定性斑块的发生率大于无以上病史者(均P＜0.05);不稳定斑块组HDL水平低于稳定性斑块组,而LDL水平则相反(P＜0.05,P＜0.001).结论 缺血性脑血管病患者颈动脉粥样硬化斑块不稳定性与高血压、糖尿病、血脂异常、吸烟有关。

Article--Diagnosis and management of dural carotid–cavernous sinus fistulas

A carotid-cavernous sinus fistula (CCF) is an abnormal communication between the cavernous sinus and the carotid arterial system. Some fistulas are characterized by a direct connection between the cavernous segment of the internal carotid artery (ICA) and the cavernous sinus, whereas others consist of a communication between the cavernous sinus and one or more meningeal branches of the ICA, external carotid artery, or both. These dural fistulas usually have low rates of arterial blood flow and until recently were difficult to diagnose and treat. In this paper, the author discusses the anatomy, pathogenesis, clinical manifestations, diagnosis, treatment, and prognosis of dural CCFs.

MR Angiography at 3 T for Assessment of the External Carotid Artery System

A number of clinical situations exist in which high-resolution depiction of the external carotid artery system is required, a task not previously addressed by MR angiography. The purpose of this study was to evaluate the extent to which high-spatial-resolution MR angiography at 3 T can be used to map the normal external carotid artery system. Twenty-three consenting adult patients were prospectively evaluated. Images acquired were evaluated by two independent observers, and each branch vessel was scored with regard to image quality, presence and grade of stenoses, and artifacts. Interobserver agreement regarding image quality and the presence and degree of stenosis was tested using the kappa coefficient. Differences in quality ratings between the two observers were assessed using the paired Student's t test. Of 828 vessels analyzed, 92.63% were designated of diagnostic quality with no significant difference between the observers' image quality scores (p = 0.63). Good agreement was determined regarding image quality achieved (kappa = 0.716). All examinations were free of artifact sufficient to interfere with confident interpretation. Excellent correlation was seen with regard to stenosis detection and grading (kappa = 0.857). Of the external carotid artery systems assessed, 82.6% showed conventional anatomic vascular branching. High-spatial-resolution, 3D contrast-enhanced MR angiography at 3 T using sagittal source data acquisition and an advanced acceleration factor of 6 allows high-quality (92.63% of arterial segments) visualization of the external carotid artery system, with complete head and neck vascular coverage.

Facial angiology – boon or bane?

It is an established fact that unlike the rest of our body, only the brain enjoys the extensive multiplicity of vascular supply and anastamosis seen in our face. Branches from Internal & External Carotid artery systems, collateral non-valved venous drainage with emissary and anastomotic veins & venous plexuses, and a dense capillary bed capable of producing a blush or a blanch in an instant the above functions are important aspects of this phenomenon. This poster demonstrates how this proves to be a huge helping hand in the outcome of maxillo-facial treatment, though also leading to virtually uncontrollable blood-bath in trauma and surgery.

Peripheral arterial obliterative disease and physical activity

Regular physical exercise represents an essential element in treating patients with second-stage peripheral arterial occlusive disease. Peripheral arterial occlusive disease is a characteristic clinical manifestation of atherothrombotic processes. Its prevalence is 2-3%, consequently, it is estimated to be 200,000-300,000 patients in Hungary. Coronary artery disease and atherothrombosis of the carotid artery system may frequently coexist with peripheral arterial obliterative disease. Treatment of peripheral arterial obliterative disease influences their prevalence and prognosis as well. The main aim of regular physical exercise is to improve the quality of life of patients by increasing the functional capacity of the lower limbs. During exercise beneficial vascular changes occur like haemodynamic changes consisting of increasing pressure-gradient of stenotic artery and opening of collateral vessels, as well as improvement of the endothelial dysfunction. It favourably influences lipid profile by decreasing LDL cholesterol and increasing HDL cholesterol. Physical exercise beneficially affects blood rheology as well. It also brings about structural changes in the skeletal muscles, increases the enzyme levels in the oxidative metabolic processes and enhances the density of capillaries in the skeletal muscle fibres. According to the data published so far, patients with peripheral arterial obliterative disease are recommended to take part in supervised treadmill walking at least 3 days per week for 30-60 minutes each session containing 5-5 minute warm-up and cool-down periods. The training should be of intermittent intensity at the pain-free threshold. The physiological benefits are optimised at 3-6 months. The home-based training programme is also remarkably useful.

Readers Discuss: the Business of Nursing

Recent researches demonstrate that damage of executive function is an early manifestation of vascular cognitive disorder.To investigate the executive functions of patients with transient ischemic attack (TIA).Case control.Department of Neurology, the First Affiliated Hospital of Xinxiang Medical College.A total of 83 TIA patients (46 males and 37 females, aged 32–74 years) were selected from Department of Neurology, the First Affiliated Hospital of Xinxiang Medical College from July 2005 to December 2006. The diagnosis of TIA was established by the criteria of cerebrovascular diseases made by the Fourth National Cerebrovascular Disease Meeting. In these cases, forty-five patients (54%) were involved in internal carotid artery, and thirty-eight patients (46%) were involved in vertebral basilar system. Fifty healthy adults (Control group: 28 males and 22 females, aged 32–74 years) were chosen from retiree in community and family of patients. All of them were right-handedness, without cerebrovascular disease, cerebral trauma, inborn oligophrenia, and hearing and visual disorders; also they had no anxiety and depression nearly one week. In addition, all the subjects cooperated with examination.After TIA diagnosis, all patients received neuropsychological examination, including attention and inhibition, working memory, flexibility, planning and diversion, based on Stroop tests (C and CW) and the Wisconsin card sorting tests (WCST). WCST test: The edition revised by Nelson was used. We would take the times of sorting, incorrect response, persistent incorrect response, and randomly incorrect response as the index of evaluation. Stroop tests: The edition revised by Trenarry was used and this test had two types: form color and form color-word. Their incorrect response and response time were recorded for data analysis in the end.Results of WCST test and Stroop tests.A total of 83 TIA patients and 50 healthy subjects were involved in the final analysis. Items of Stroop tests, including response time of Stroop-C test, incorrect response of Stroop-C test, response time of Stroop-CW test and incorrect response of Stroop-CW test, and items of WCST, including incorrect response, persistent incorrect response and random incorrect response, between internal carotid artery system and vertebral basilar artery system were (93.87±24.39) s, 3.16±3.97, (228.46±68.13) s, 12.91±10.56, 55.42±20.38, 26.58±10.41, 28.62±11.22; (96.76±24.75) s, 3.89±4.77, (223.46±72.54) s, 18.71±13.80, 52.47±22.25, 28.82±16.20, 23.39±9.72, respectively; this was higher than those in the control group [(52.10±12.18) s, 1.68±1.97, (134.86±34.15) s, 4.22±4.21, 32.46±17.97, 14.42±8.47, 18.24±10.24, P < 0.05–0.01]. Times of sorting of WCST between internal carotid artery system and vertebral basilar artery system were obviously lower than those in the control group (8.27±2.73, 8.66±2.77, 11.22±2.41, P < 0.01). However, there were no significant differences between internal carotid artery system and vertebral basilar artery system (P > 0.05).Patients with TIA have executive dysfunctions, and the dysfunctions have no difference between internal carotid artery system and vertebral basilar artery system.

Primary treatment of an indirect carotid cavernous fistula by injection of N-butyl cyanoacrylate in the dural wall of the cavernous sinus

Background Carotid cavernous fistulae are abnormal communications between the carotid artery system and the cavernous sinus. Endovascular treatment is the treatment of choice, but because of their heterogeneous etiology and anatomy, an appropriate treatment plan must be tailored for each patient. Case Description A 77-year-old diabetic woman presented with rapid onset of right eye pain, conjunctivitis, and chemosis. Angiography revealed an indirect CCF located in the posterior wall of the right cavernous sinus. N-Butyl cyanoacrylate was injected directly into the fistula site in the dural wall via a microcatheter, resulting in a cure. Conclusion We describe an unconventional treatment of an indirect CCF from an IPS approach. One type D 2 CCF was treated successfully using only N-butyl cyanoacrylate injected directly at the fistula site. This was achieved by microcatheterization of the fistula in the posterior wall of the right cavernous sinus.

Fístulas carótido-cavernosas. A propósito de dos casos

Carotid-cavernous fistulas are uncommon anomalous communications between the venous cavernous sinus and the carotid arterial system. We present two cases studied at our center. We show the characteristic CT, MRI, and orbital ultrasound findings and review the relevant literature.

Executive function during transient ischemic attacks*

Background Recent researches demonstrate that damage of executive function is an early manifestation of vascular cognitive disorder. Objective To investigate the executive functions of patients with transient ischemic attack (TIA). Design Case control. Setting Department of Neurology, the First Affiliated Hospital of Xinxiang Medical College. Participants A total of 83 TIA patients (46 males and 37 females, aged 32–74 years) were selected from Department of Neurology, the First Affiliated Hospital of Xinxiang Medical College from July 2005 to December 2006. The diagnosis of TIA was established by the criteria of cerebrovascular diseases made by the Fourth National Cerebrovascular Disease Meeting. In these cases, forty-five patients (54%) were involved in internal carotid artery, and thirty-eight patients (46%) were involved in vertebral basilar system. Fifty healthy adults (Control group: 28 males and 22 females, aged 32–74 years) were chosen from retiree in community and family of patients. All of them were right-handedness, without cerebrovascular disease, cerebral trauma, inborn oligophrenia, and hearing and visual disorders; also they had no anxiety and depression nearly one week. In addition, all the subjects cooperated with examination. Methods After TIA diagnosis, all patients received neuropsychological examination, including attention and inhibition, working memory, flexibility, planning and diversion, based on Stroop tests (C and CW) and the Wisconsin card sorting tests (WCST). ▪ WCST test: The edition revised by Nelson was used. We would take the times of sorting, incorrect response, persistent incorrect response, and randomly incorrect response as the index of evaluation. ▪ Stroop tests: The edition revised by Trenarry was used and this test had two types: form color and form color-word. Their incorrect response and response time were recorded for data analysis in the end. Main outcome measures Results of WCST test and Stroop tests. Results A total of 83 TIA patients and 50 healthy subjects were involved in the final analysis. Items of Stroop tests, including response time of Stroop-C test, incorrect response of Stroop-C test, response time of Stroop-CW test and incorrect response of Stroop-CW test, and items of WCST, including incorrect response, persistent incorrect response and random incorrect response, between internal carotid artery system and vertebral basilar artery system were (93.87±24.39) s, 3.16±3.97, (228.46±68.13) s, 12.91±10.56, 55.42±20.38, 26.58±10.41, 28.62±11.22; (96.76±24.75) s, 3.89±4.77, (223.46±72.54) s, 18.71±13.80, 52.47±22.25, 28.82±16.20, 23.39±9.72, respectively; this was higher than those in the control group [(52.10±12.18) s, 1.68±1.97, (134.86±34.15) s, 4.22±4.21, 32.46±17.97, 14.42±8.47, 18.24±10.24, P < 0.05–0.01]. Times of sorting of WCST between internal carotid artery system and vertebral basilar artery system were obviously lower than those in the control group (8.27±2.73, 8.66±2.77, 11.22±2.41, P < 0.01). However, there were no significant differences between internal carotid artery system and vertebral basilar artery system ( P > 0.05). Conclusion Patients with TIA have executive dysfunctions, and the dysfunctions have no difference between internal carotid artery system and vertebral basilar artery system.

Clinical spectrum of spontaneous carotid-cavernous fistula

A carotid-cavernous fistula (CCF) is an abnormal communication between the cavernous sinus and the carotid arterial system. A CCF is divided into two categories, direct and indirect. Direct fistulas usually account for 70 to 90% of all CCF. Spontaneous, low-flow fistulas are usually associated with atherosclerosis, hypertension and collagen vascular disease or may develop in females during peripartum period. The elderly age group, especially women are at increased risk. We report three cases of spontaneous CCF presenting with ocular manifestations and hypertension, without any collagen vascular disease. One case was a direct variety and the other two were of indirect variety.

Experimental Model Evaluation of Filter Trapping After Embolectomy Using the Merci System-Supplemental Technique for Merci Retrieval Procedure-

Examination of embolectomy using the Merci Retrieval System using experimental stroke models demonstrated that aspiration is not adequate to remove larger clots. The effectiveness of filter trapping was examined using the same models. A silicone model of the carotid artery system with model blood clot was incorporated in a laboratory pulsatile flow system. Embolectomy was performed using the Merci Retrieval System. Any clot not evacuated through the balloon guide catheter was trapped with a distal protection filter device developed for cervical stenting. The clot could not be sucked into the guide catheter by the recommended procedures in nine of 15 trials. Trapping failed in only one trial, in which the clot passed through a gap between the edge of the filter orifice and the inner model lumen. A clot was withdrawn to the catheter tip trapped across the edge of the orifice frame in one trial, and a very large clot was trapped across the filter orifice in two trials. Even clots made by the same method showed variation in properties, especially hardness, which may affect the effectiveness of aspiration. The aspiration procedure recommended for the Merci Retrieval System did not remove the large clots formed by embolectomy. The trapping procedure using a filter device without an orifice frame was effective to solve this problem.

Anatomically specific clinical examination of the carotid arterial tree

Clinical examination of the carotid arterial system has traditionally been used as a non-specific screening tool of atherosclerotic pathology. Because it has not yet been shown to delineate the precise location and grade of stenosis, further imaging modalities, such as duplex ultrasound, digital subtraction angiography, computed tomography and magnetic resonance, are currently used to obtain this information. These, however, have been shown to be susceptible to inaccuracies. Herein, a new protocol for bedside clinical examination that may define anatomical locality and degree of disease is presented. This consists of palpating the carotid pulse and auscultating for bruits along the course of the common carotid, internal carotid and external carotid arteries, as defined by surface anatomical landmarks from the lower neck to the pharynx. This protocol is not to replace more conventional methods of disease assessment but, in an era of diminishing clinical skills, may add to the overall evaluation of the pathological carotid tree.

Endoscopic Sinus Surgery for the Treatment of Vascular Tumors

This study points out the effectiveness of the endoscopic approach for the treatment of vascular lesions such as angiofibroma, hemangioma, and hemangiopericytoma involving the nose and paranasal sinuses. We performed a retrospective study at an academic tertiary referral center. Thirteen patients, diagnosed with vascular tumors of the nose and paranasal sinuses were treated endoscopically between February 1996 and July 2003. All patients underwent endonasal endoscopic surgery. Preoperative angiography with embolization was performed in all but two cases. The follow-up of this series varied from 6 to 75 months (mean, 23 months); only one recurrence (8%) was observed in the juvenile angiofibroma group encountered 20 months postoperatively. This recurrence was again treated endoscopically. The average intraoperative blood loss for the removal of the juvenile angiofibroma group was 300 mL and it was 100 mL for the other vascular tumors. Endoscopic treatment alone is an effective approach for the removal of selected cases of vascular tumors. Even in the presence of a lesion with limited intracranial extension, the tumor still may be amenable to an endoscopic approach alone. On the contrary, this is not true if the intracranial extension receives feeding vessels from the internal carotid arterial system.