Internal Carotid Artery (internal + carotid_artery)

Distribution by Scientific Domains
Distribution within Medical Sciences

Terms modified by Internal Carotid Artery

  • internal carotid artery stenosis

  • Selected Abstracts


    RADIONECROSIS OF INTERNAL CAROTID ARTERY IN NASOPHARYNGEAL CARCINOMA PRESENTING AS EPISTASIS

    ANZ JOURNAL OF SURGERY, Issue 3 2000
    W. K. Mak
    No abstract is available for this article. [source]


    Caliber Fluctuations of Cervical Internal Carotid Artery and Migraine With Aura: A Possible Vasospasm Detected by Ultrasonographic Examinations

    HEADACHE, Issue 7 2009
    Susanna Usai MD
    Caliber fluctuations of extra- and intracranial arteries, mostly related to vasospasm, are often recognized in various neurological conditions. We report a case of a 33-year-old woman affected by migraine with and without aura who exhibited a possible cervical internal carotid artery vasospasm, detected by ultrasound, before a typical migraine aura. [source]


    The Accuracy of Transcranial Doppler in the Diagnosis of Stenosis or Occlusion of the Terminal Internal Carotid Artery

    JOURNAL OF NEUROIMAGING, Issue 4 2004
    Jose C. Navarro MD
    ABSTRACT Background and Purpose. Transcranial Doppler (TCD) can detect intracranial stenoses and occlusions that can help in the diagnosis and management of ischemic stroke. The accuracy parameters for lesions located in the terminal internal carotid artery (TICA) are less known, unlike other basal cerebral vessels. Patients and Methods. The authors studied consecutive patients referred for TCD who underwent contrast angiography or magnetic resonance angiography. They calculated the sensi tivity, specificity, positive and negative predictive values (PPV and NPV), and likelihood ratios. Results. Forty-three patients had TCD and angiography: mean age was 57 ± 20 years, and 65% were men. Twenty-two patients were diagnosed with TICA stenosis or occlusion on TCD underwent angiography. Four patients had abnormal TCD findings that were not confirmed by angiography. Two of 21 patients with normal TCD showed mod erate (< 50%) stenosis of the TICA and cavernous segment of the internal carotid artery at angiography. Accuracy parameters for TCD were as follows: sensitivity = 90% (confidence interval [CI], 63%-96%), specificity = 83% (CI, 61%-94%), PPV = 82%, NPV = 86%, positive likelihood ratio = 5, and negative likelihood ratio = 0.17. Conclusions. TCD is a sensitive screening tool for the lesions in the TICA. Specificity is likely affected by a wide spectrum of the stenosis severity shown at angiography and time lags between the studies. [source]


    Surgical Removal of Jugular Paragangliomas After Stenting of the Intratemporal Internal Carotid Artery: A Preliminary Report

    THE LARYNGOSCOPE, Issue 5 2006
    Mario Sanna MD
    Abstract Objective: Jugular paragangliomas with extensive involvement of the internal carotid artery (ICA) represent a true challenge for surgeons, especially in the presence of inadequate collateral circulation through the circle of Willis. The aim of our study is to present a preliminary report of our experience with the surgical removal of three such cases using the stenting of the ICA as the method of choice for protecting and preserving the integrity of the artery. Methods: This retrospective study was conducted at Gruppo Otologico, a private referral center for neurotology and skull base surgery. The subjects of our study are three cases of jugular paragangliomas with extensive involvement of the ICA and inadequate collateral circulation. These cases are the first three cases operated at our center after stenting of the intratemporal portion of the ICA. Results: Complete surgical removal of the tumor, including the part involving the ICA, was achieved in all cases. Over a follow-up period of 22 to 30 months, no complications occurred and the patency of the stented arteries was preserved. Conclusion: Although more follow-up is still needed before establishing the exact long-term outcome of stenting the intratemporal ICA, our preliminary report shows that the stent has facilitated the complete surgical removal of the tumor, preserving the integrity of the ICA. [source]


    Bilateral Internal Carotid Artery Dissection Mimicking Inflammatory Demyelinating Disease

    JOURNAL OF NEUROIMAGING, Issue 4 2003
    C. Lie MD
    ABSTRACT Background and Purpose. Internal carotid artery (ICA) dissection (ICAD) may be extremely difficult to diagnose only on the basis of historical information and clinical signs, and even standard brain imaging (computed tomography [CT], T2-weighted magnetic resonance imaging [MRI]) may not be sufficient to delineate the underlying pathology clearly, as shown in this case. Methods. The clinical presentation and parenchymal lesion pattern on CT were suggestive of inflammatory demyelinating disease, and additional multiparametric MRI was per-formed. Results. Diffusion-weighted MRI, magnetic resonance angiography, and perfusion-weighted MRI revealed acute ischemic lesions, bilateral ICA obstruction, and bilateral hypoperfusion in the middle cerebral artery territories. Bilateral ICAD was confirmed by Doppler and duplex ultrasound, and anticoagulation therapy was initiated. A follow-up examination showed recanalization of the obstructed ICAs and the normalization of cerebral perfusion. Conclusion. This case illustrates the importance of demonstrating the pathology and the value of multiparametric MRI techniques for the diagnosis and monitoring of ICAD and its hemodynamic consequences. [source]


    Transesophageal and Transpharyngeal Ultrasound Demonstration of Reversed Diastolic Flow in Aortic Arch Branches and Neck Vessels in Severe Aortic Regurgitation

    ECHOCARDIOGRAPHY, Issue 4 2004
    Deepak Khanna M.D.
    In the current study, we describe an adult patient with torrential aortic regurgitation due to an aortic dissection flap interfering with aortic cusp motion, in whom a transesophageal echocardiogram with the probe positioned in the upper esophagus and transpharyngeal ultrasound examination demonstrated prominent reversed flow throughout diastole in the left subclavian, left vertebral, left common carotid, and left internal carotid arteries. Another unique finding was the demonstration of aortic valve leaflets held in the fully opened position in diastole by the dissection flap as it prolapsed into the left ventricular outflow tract, dramatically documenting the mechanism of torrential aortic regurgitation in this patient. (ECHOCARDIOGRAPHY, Volume 21, May 2004) [source]


    Bilateral spontaneous dissection of the internal carotid arteries

    EUROPEAN JOURNAL OF NEUROLOGY, Issue 1 2004
    A. Spalloni
    No abstract is available for this article. [source]


    Headache As Only Symptom in Multiple Cervical Artery Dissection

    HEADACHE, Issue 5 2001
    Maarten Buyle MD
    We describe a patient with atypical headache as the only presenting symptom of spontaneous triple cervical artery dissection. As the patient suffered from arterial hypertension, a causative relation between headache and arterial hypertension was initially taken into consideration. However, four-vessel arteriography disclosed a dissection of both internal carotid arteries and the right vertebral artery. This unique case highlights the value of conventional arteriography for diagnosing cervical artery dissection. Since multiple cervical artery dissections are not rare, all cervical arteries should be examined by means of conventional arteriography when a dissection is suspected. [source]


    Color Doppler sonographic evaluation of flow volume of the internal carotid and vertebral arteries after carotid endarterectomy

    JOURNAL OF CLINICAL ULTRASOUND, Issue 5 2010
    Anka Mitrasinovic MD
    Abstract Background. To measure by Doppler sonography the blood flow volume (BFV) of the ipsilateral and contralateral extracranial internal carotid arteries (ICAs) and both vertebral arteries (VAs) before and after a carotid endarterectomy (CEA) of the ICA. We correlated the result with the degree of stenosis of the ICA. Method. One hundred seven patients who had a CEA were divided into 2 groups. Group I consisted of subjects with stenosis of ipsilateral ICA of ,70% to near occlusion and Group II included subjects with near occlusion. The Doppler sonographic examinations were performed 1 day before the CEA, 7 days after the CEA, and 1 month after the CEA. The peak systolic velocity, end-diastolic velocity, time-averaged maximum blood flow velocity, resistance index of the ipsilateral ICA, and the BFV of both ICAs and both VAs were calculated. Result. There was a significant increase in the peak systolic velocity, maximum blood flow velocity, and the BFV of the ipsilateral ICA after the CEA. The BFV of the contralateral ICA and both VAs were not significantly altered after the CEA in both groups. Conclusion. The main CEA hemodynamic effect was an increase in the BFV of the ipsilateral ICA regardless of the degree of stenosis. © 2010 Wiley Periodicals, Inc. J Clin Ultrasound, 2010 [source]


    Color and power Doppler sonography of extracranial and intracranial arteries in moyamoya disease

    JOURNAL OF CLINICAL ULTRASOUND, Issue 2 2006
    Li-Tao Ruan MD
    Abstract Purpose: To study the hemodynamic characteristics of moyamoya disease with color Doppler (CD) and power Doppler (PD) sonography. Methods: The hemodynamic parameters of intracranial and extracranial arteries from 17 patients with moyamoya disease confirmed via digital subtraction angiography and 30 healthy controls were studied with conventional and transcranial CD and PD. Results: The moyamoya vessels were detected as scattered color Doppler signal with low velocity and a low resistance index (RI) at the base of the brain in 10 of the 17 patients. The RI of the common carotid arteries and the internal carotid arteries of the patients was significantly higher, whereas the peak velocity was lower than in controls. The posterior carotid arteries were more frequently involved in children (43.8%) than in adults (5.6%). Conclusions: Transcranial CD and PD can be used to demonstrate the stenosis and occlusion of intracranial arteries and the abnormal vascular network at the base of the brain in most cases. Combined with the hemodynamic characteristics of extracranial arteries and the symptoms of the patients, an accurate diagnosis of moyamoya disease could be made in the majority of cases using PD. © 2006 Wiley Periodicals, Inc. J Clin Ultrasound 34:60,69, 2006 [source]


    Echocardiographic Findings of Patients With Retinal Ischemia or Embolism

    JOURNAL OF NEUROIMAGING, Issue 3 2002
    Mikael Mouradian MD
    ABSTRACT Background and Purpose. A potential source of emboli is not detected in more than 50% of patients with retinal arterial occlusive events. Echocardiographic studies are not always included in the diagnostic workup of these patients. The authors studied the diagnostic yield of transthoracic (TTE) and/or transesophageal (TEE) echocardiography in identifying potential sources of emboli in patients with retinal ischemia or embolism. Methods. In a prospective study, 73 consecutive patients with clinically diagnosed retinal ischemia or embolism received a standardized diagnostic workup including retinal photography, echocardiography, and imaging studies of the internal carotid arteries. TTE was performed in 83.6% of patients, TEE was performed in 5.5% of patients, and both TTE and TEE were per-formed in 11.0% of patients. Ophthalmological diagnoses consisted of amaurosis fugax (n= 28), asymptomatic cholesterol embolism to the retina (n= 34), and branch or central retinal artery occlusion (n= 11). Results. Echocardiography identified a potential cardiac or proximal aortic source for embolism in 16 of 73 (21.9%) patients, including 8 who also had either atrial fibrillation or internal carotid artery stenosis of more than 50% on the side of interest. Thus, 8 of 73 (11.0%) patients had lesions detected only by echocardiography. The most commonly identified lesions were proximal aortic plaque of more than 4 mm thickness (n= 7, 9.6%) and left ventricular ejection fraction of less than 30% (n= 6, 8.2%). TEE was particularly helpful in identifying prominent aortic plaques. Conclusion. Echocardiography frequently identifies lesions of the heart or aortic arch that can act as potential sources for retinal ischemia or embolism. Further studies are needed to evaluate the prognostic and therapeutic relevance of these findings. [source]


    Semiautomatic segmentation and stenosis quantification of 3D contrast-enhanced MR angiograms of the internal carotid artery

    MAGNETIC RESONANCE IN MEDICINE, Issue 4 2004
    Cornelis M. van Bemmel
    Abstract A technique is presented for the segmentation and quantification of stenosed internal carotid arteries (ICAs) in 3D contrast-enhanced MR angiography (CE-MRA). Segmentation with sub-pixel accuracy of the ICA is achieved via level-set techniques in which the central axis serves as the initialization. The central axis is determined between two user-defined points, and minimal user interaction is required. For quantification, the cross-sectional area is measured in the stenosis and at a reference segment in planes perpendicular to the central axis. The technique was applied to 20 ICAs. The variation in measurements obtained by this method in comparison with manual observations was 8.7%, which is smaller than the interobserver variability among three experts (11.0%). Magn Reson Med 51:753,760, 2004. © 2004 Wiley-Liss, Inc. [source]


    Pediatric moyamoya disease: An analysis of 410 consecutive cases

    ANNALS OF NEUROLOGY, Issue 1 2010
    Seung-Ki Kim MD
    Objective Moyamoya disease (MMD) is a cerebrovascular occlusive disease of the bilateral internal carotid arteries that causes a compensatory abnormal vascular network at the base of brain. The rare incidence and various surgical techniques applied have limited the clinical research on MMD. Methods We conducted a retrospective analysis of the surgical outcome of 410 pediatric MMD patients. All patients were treated in a relatively uniform scheme at a single institution. The surgical procedures consisted of bilateral encephaloduroarteriosynangiosis augmented by bifrontal encephalogaleo-/periosteal synangiosis. Logistic regression analyses were applied to reveal the prognostic factors for surgical outcome. Results The overall clinical outcome was excellent in 66%, good in 15%, fair in 15%, and poor in 4% of the patients. Therefore, 81% of the patients had a favorable clinical outcome (excellent and good). Multivariate analyses revealed that infarction on presentation was associated with unfavorable clinical outcome (odds ratio [OR], 2.85; 95% confidence interval [CI], 1.49,5.46; p < 0.01) and decreased vascular reserve only on single-photon emission computerized tomography (OR, 0.07; 95% CI, 0.01,0.52; p < 0.01), with favorable clinical outcome. Interpretation Our results indicate that an early diagnosis and active intervention before establishment of irreversible hemodynamic change are essential to achieve a favorable clinical outcome in children with MMD. ANN NEUROL 2010;68:92,101 [source]


    Carotid Intima-Media Thickness and Plaques in Hemodialysis Patients

    ARTIFICIAL ORGANS, Issue 9 2000
    Radovan Hojs
    Abstract: Atherosclerosis is accelerated in hemodialysis patients. Using B-mode ultrasonography, we compared intima-media thickness (IMT) and the prevalence of plaques in the common carotid and internal carotid arteries in 28 randomly selected hemodialysis patients with that in 28 age- and sex-matched normal controls. The IMT values of the common carotid and internal carotid arteries were higher in hemodialysis patients than in controls with more hemodialysis patients having plaques. In hemodialysis patients, there was a relationship between age and IMT in the common carotid arteries, in the area of bifurcation, and in the internal carotid arteries. We found no relationship between IMT and atherosclerotic risk factors or duration of hemodialysis treatment. IMT at all sites correlated with the number of plaques. Age was the only significant determinant for number of plaques. The results indicate that hemodialysis patients showed advanced atherosclerosis in the carotid arteries compared with age- and sex-matched normal subjects. [source]


    The effect of statin therapy on the progression of carotid artery stenosis in relation to stenosis severity

    ACTA NEUROLOGICA SCANDINAVICA, Issue 1 2010
    O. Hegland
    Objectives,,, To examine the effect of early statin treatment on progression of arteriosclerosis in internal carotid arteries (ICA); to compare the progression of arteriosclerosis in ICA of patients treated with a statin to the progression seen in drug-naïve patients. Patients and methods,,, We performed repetitive Doppler scans of 363 carotid arteries with ICA stenosis ,40% in 254 patients over time. Information on statin therapy and other risk factors for stroke were correlated with the annual change in degree of ICA stenosis. Results,,, In statin-treated patients, 19% of ICA stenosis showed a progression while 74% showed a regression of stenosis. In statin - naïve patients, 63% of stenotic arteries showed a progression, while a reduction could be observed in 28%. Decrease of ICA stenosis was most accentuated in patients with a mild stenosis and was independent of serum cholesterol levels. Conclusion,,, Treatment with statins already in early stages of ICA stenosis might delay the progression and even reverse the degree of stenosis. [source]


    Carotid artery ectasia coexistent with primary open angle glaucoma

    CLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 1 2001
    Mark F Ellis FRACO
    ABSTRACT A 60-year-old smoker presented with high intraocular pressure in the right eye with a right afferent pupil defect and visual field suggestive of primary open angle glaucoma in the right eye only, when an examination 2 years earlier had revealed no hint of ocular pathology. Radiological investigations demonstrated prominent ectasia of the internal carotid arteries extending into the proximal middle cerebral arteries. The changes in the carotids extended throughout the cavernous sinus regions, encroached on the under surface of the optic chiasm and were closely related to the internal aspects of both optic canals. In primary open angle glaucoma management, neural imaging is not normally recommended; however, neural imaging investigations should be considered if the presentation is not typical of a chronic bilateral optic neuropathy. [source]


    Contralateral EEG Slowing and Amobarbital Distribution in Wada Test: An Intracarotid SPECT Study

    EPILEPSIA, Issue 2 2000
    Seung Bong Hong
    Summary: Purpose: To relate the occurrence of contralateral electroencephalogram slowing (CES) to amobarbital distribution, we performed electroencephalogram (EEG) monitoring and intracarotid single photon emission computed tomography (SPECT) during an intracarotid amobarbital procedure (IAP). Methods: IAP was performed on 22 patients with temporal lobe epilepsy. CES was defined as the occurrence of significant EEG slowing on the contralateral hemisphere (>50% of the ipsilateral hemisphere slowing) after amobarbital injection. To map the distribution of the amobarbital, we injected a mixture of amobarbital and 99m technetium-ethylcysteinate dimer (99m Tc-ECD) into the internal carotid artery and performed a brain SPECT 2 h later. In the SPECT images, regions of interest were determined by ipsilateral and contralateral anterior cerebral artery territories (iACA, cACA), ipsilateral and contralateral middle cerebral artery territories (iMCA, cMCA), and ipsilateral and contralateral posterior cerebral artery territories (iPCA, cPCA), as well as ipsilateral and contralateral anterior and posterior mesial temporal regions (iAMT, cAMT, iPMT, cPMT). The perfusion of amobarbital was interpreted visually in each region. Results: Amobarbital was distributed in the iMCA in all the patients; in the iACA in 20 (90.9%) patients; in the iAMT in 14 (63.5%); and in the iPCA and iPMT in only two (9.1%). CES was observed in 13 (59.1%) patients. Cross-perfusion of amobarbital in limited areas of the cACA were observed in only four of 13 patients. Wada retention memory scores (WRMS) showed no significant difference between the CES- (n = 9) and CES+ (n = 13) groups. Conclusions: Amobarbital rarely perfused the iPCA territory and the iPMT region and was rarely delivered to the contralat-eral hemisphere. The occurrence of CES was not related to the cross-perfusion of amobarbital. CES appears to be produced by a transient functional disconnection from the ipsilateral hemisphere. [source]


    Ruptured symptomatic internal carotid artery dorsal wall aneurysm with rapid configurational change.

    EUROPEAN JOURNAL OF NEUROLOGY, Issue 10 2010
    Clinical experience, management outcome: an original article
    Background:, Aneurysms located at non-branching sites, protruding from the dorsal wall of the supraclinoid internal carotid artery (ICA) with rapid configurational changes, were retrospectively reviewed in effort to identify and characterize these high-risk aneurysms. Methods:, A total of 447 patients with 491 intracranial aneurysms were treated from March 2005 to August 2008, and of these, eight patients had ICA dorsal wall aneurysms. Four of them suffered subarachnoid hemorrhage (SAH), and all had aneurysms undergoing rapid configuration changes during the treatment course. Digital subtraction cerebral angiography (DSA) performed soon after the SAH events. Data analyzed were patient age, sex, Hunt and Kosnik grade, time interval from first DSA to second DSA, aneurysm treatment, and modified Rankin scale score after treatment for 3 months. Success or failure of therapeutic management was examined among the patients. Results:, Digital subtraction cerebral angiography showed only lesions with small bulges in the dorsal walls of the ICAs. However, the patients underwent DSA again for re-bleeding or for post-treatment follow-up, confirming the SAH source. ICA dorsal wall aneurysms with rapid growth and configurational changes were found on subsequent DSA studies. Conclusions:, Among the four patients, ICA dorsal wall aneurysms underwent rapid growth with configurational change from a blister type to a saccular type despite different management. ICA trapping including the lesion segment can be considered as the first treatment option if the balloon occlusion test (BOT) is successful. If a BOT is not tolerated by the patient, extracranial,intracranial bypass revascularization surgery with endovascular ICA occlusion is another treatment option. [source]


    Long-term follow-up of patients with asymptomatic occlusion of the internal carotid artery with good and impaired cerebral vasomotor reactivity

    EUROPEAN JOURNAL OF NEUROLOGY, Issue 10 2010
    I. Kimiagar
    Background:, Cerebral hemodynamic status might be prognostic for either the symptomatic or asymptomatic course of carotid occlusive disease. It is determined by evaluating cerebral vasomotor reactivity (VMR). We assessed VMR in asymptomatic patients with total occlusion of the internal carotid artery (ICA) and followed them to evaluate the role of impaired VMR in predicting ischaemic stroke (IS). Methods:, Thirty-five patients (21 men, mean age ± SD 68 ± 7.5 years) with unilateral asymptomatic ICA occlusion were studied by transcranial Doppler and the Diamox test (intravenous 1.0 g acetazolamide) and followed for 48 months or until reaching the end-points of IS, transient ischaemic attack, or vascular death. VMR% was evaluated by recording the percent differences in peak systolic blood flow velocities in each middle cerebral artery at baseline and after Diamox administration. Results:, Based on VMR% calculations, 14 (40%) patients had good VMRs and 21 (60%) had impaired VMRs. The global annual risk of ipsilateral ischaemic events was 5.7%. The annual ipsilateral ischaemic event risk was 1.8% in patients with good VMRs, whilst it was 7.1% in patients with impaired VMRs. An impaired VMR was significantly correlated with ipsilateral IS (Kaplan,Meier log rank statistic, P = 0.04). Conclusions:, Our results support the value of VMR assessment for identifying asymptomatic patients with carotid occlusion who belong to a high-risk subgroup for IS. New trials using extracranial-to-intracranial bypass surgery in patients with asymptomatic ICA occlusion and impaired VMRs are warranted. [source]


    Cerebral bloodflow and oxygen metabolism in borderzone and territorial infarcts due to symptomatic carotid artery occlusion

    EUROPEAN JOURNAL OF NEUROLOGY, Issue 4 2004
    J. De Reuck
    It remains controversial whether borderzone infarcts are due to compromised cerebral perfusion and whether territorial infarcts are caused by artery-to-artery emboli in case of occlusion of the internal carotid artery. The present positron emission tomography study compares with normal controls, the average regional cerebral bloodflow (rCBF), regional oxygen extraction fraction (rOEF) and regional cerebral metabolic rate for oxygen (rCMRO2) in the infarct area, the peri-infarct zone, the remaining homolateral hemisphere and in the contralateral hemisphere of 10 patients with borderzone and 17 patients with territorial infarcts, due to internal carotid artery occlusion by atherosclerosis and by cervical dissection. The steady-state technique with oxygen-15 was used. A nearly significant increase of rOEF with lowered rCBF and rCMRO2 was observed in the peri-infarct zone of patients with territorial infarcts. In patients with borderzone infarcts rCMRO2 was decreased in the peri-infarct zone, in the remaining homolateral hemisphere and in the contralateral hemisphere without changes in rCBF and rOEF. The present study finds no arguments that impaired cerebral perfusion is a more frequent cause of borderzone than of territorial infarcts. [source]


    Heart and carotid artery disease in stroke patients with intermittent claudication

    EUROPEAN JOURNAL OF NEUROLOGY, Issue 5 2000
    X. F. Liu
    Much has been published on the natural history of intermittent claudication (IC), but little is known about the clinical features of stroke patients with IC. The purpose of this study was to examine clinical features and risk factors in stroke patients with or without IC, including heart disease and carotid artery disease. A hospital-based study was conducted of 3901 stroke patients, who were prospectively coded and entered into a computerized databank. Of these patients, 219 had symptoms of IC. Patients were subdivided by age into 10-year categories. There were at least 12 times more non-IC than IC patients in each category. An age-matched random sample was obtained containing 12 non-IC cases for each IC case, resulting in 219 cases of IC and 2628 non-IC cases. The prevalence of IC in the total stroke population was 5.6%. IC prevalence increased sharply with age until about 70 years. Cardiac ischaemia and internal carotid artery (ICA) disease were significantly more frequent in stroke with IC than without IC. IC patients also exhibited a higher prevalence of atherosclerotic disease as well as other risk factors such as smoking, hypercholesterolaemia, elevated haematocrit, and family history of stroke. Ischaemic heart disease and ICA disease are especially common in stroke with IC. IC, large artery disease and stroke share similar risk factors. IC symptoms in stroke patients may indicate extensive generalized atherosclerosis. [source]


    Feature extraction by autoregressive spectral analysis using maximum likelihood estimation: internal carotid arterial Doppler signals

    EXPERT SYSTEMS, Issue 4 2008
    Elif Derya Übeyli
    Abstract: In this study, Doppler signals recorded from the internal carotid artery (ICA) of 97 subjects were processed by personal computer using classical and model-based methods. Fast Fourier transform (classical method) and autoregressive (model-based method) methods were selected for processing the ICA Doppler signals. The parameters in the autoregressive method were found by using maximum likelihood estimation. The Doppler power spectra of the ICA Doppler signals were obtained by using these spectral analysis techniques. The variations in the shape of the Doppler spectra as a function of time were presented in the form of sonograms in order to obtain medical information. These Doppler spectra and sonograms were then used to compare the applied methods in terms of their frequency resolution and the effects in determination of stenosis and occlusion in the ICA. Reliable information on haemodynamic alterations in the ICA can be obtained by evaluation of these sonograms. [source]


    Postradiation nasopharyngeal necrosis in the patients with nasopharyngeal carcinoma,

    HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 6 2009
    Yi-Jun Hua MD
    Abstract Background Radiation-induced nasopharyngeal necrosis is a consequential late effect in the patients with nasopharyngeal carcinoma (NPC). Patients with NPC who have been treated with high-dose radiotherapy are at risk of developing postradiation nasopharyngeal necrosis (PRNN). However, the analysis of PRNN with a significant cohort of patients has not been reported in English-language literature. In this study, we aimed to evaluate PRNN in 28 patients with NPC. Methods From June 2006 to December 2007, 28 patients were diagnosed with PRNN with pathologic evidence. Surgical procedure of endoscopy-guided debridement and systemic anti-inflammatory treatments were conducted for the patients. Their clinical features, treatment procedures, and outcomes were analyzed retrospectively. Results Clinical symptoms such as foul odor and headache were alleviated in all, 8 patients were cured of their PRNN, 9 patients with exposed internal carotid artery died of sudden nasopharyngeal massive bleeding, and 3 patients died of exhaustion (cachexia). Conclusion PRNN is an important consequential late effect of radiotherapy in the patients with NPC. Internal carotid artery erosion is a severe situation and acts as an independent prognostic factor for the patients. Diagnosis of PRNN could be made after ruling out the persistent-recurrent NPC proven by pathologic examination. Surgery is effective for improving the quality of life and for curing PRNN. © 2009 Wiley Periodicals, Inc. Head Neck, 2009 [source]


    Rupture of radiation-induced internal carotid artery pseudoaneurysm in a patient with nasopharyngeal carcinoma,Spontaneous occlusion of carotid artery due to long-term embolizing performance,

    HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 8 2008
    Kai-Yuan Cheng MD
    Abstract Background Rupture of internal carotid artery (ICA) pseudoaneurysm is a lethal complication in patients with nasopharyngeal carcinoma (NPC). Angiography is the best diagnostic and treatment method. The aim of embolization is to block the pseudoaneurysm; but sometimes, total occlusion of great vessels is ineludible. We describe a case of NPC post-radiation therapy and with ruptured pseudoaneurysm treated by angio-embolization. Methods The patient had received embolization with numerous tools such as stent grafts, balloons, and bare stents with or without filter protection. Results After failing to pass through the narrow lumen by embolizing tools, the right ICA finally occluded spontaneously by self-thrombosis. Conclusion Although the angio-embolization is a good method to resolve the problems of ruptured pseudoaneurysm, there is still high mortality and morbidity. Being aware of the clinical presentations and the changes of images may alert us to predict the happening earlier. © 2008 Wiley Periodicals, Inc. Head Neck, 2008 [source]


    Cluster Headache and Internal Carotid Artery Dissection: Two Cases and Review of the Literature

    HEADACHE, Issue 3 2008
    Andrea Rigamonti MD
    We describe 2 patients with cluster headache attacks associated with a dissection of the ipsilateral internal carotid artery at the extra,intracranial passage. These cases highlight the need for extensive neuroradiological investigation in cluster headache patients when atypical features are present. We also performed a PubMed search to review the current literature data about this association. [source]


    A giant aneurysm of internal carotid artery causing hypopituitarism

    INTERNAL MEDICINE JOURNAL, Issue 6 2010
    I. Lee
    No abstract is available for this article. [source]


    Absence of carotid rete mirabile in small tropical ruminants: implications for the evolution of the arterial system in artiodactyls

    JOURNAL OF ANATOMY, Issue 1 2007
    Katsuhiro Fukuta
    Abstract The intracranial carotid rete (or rete mirabile epidurale) is a unique blood vascular system supplying the brain of artiodactyls, which have either an involuted or no internal carotid artery. Although the lesser and greater mouse deer (Tragulus javanicus and T. napu, respectively) are ruminants, the rete mirabile epidurale is absent. In these animals, as in non-artiodactyls, such as canines, equines and humans, the complete internal carotid artery supplies the brain. It is currently uncertain whether the absence of the rete is confined to mouse deer among ruminants. The absence of the rete in mouse deer provides new insights into the evolution of the arterial system in artiodactyls. [source]


    Development of pharyngeal arch arteries in early mouse embryo

    JOURNAL OF ANATOMY, Issue 1 2002
    Tamiko Hiruma
    Abstract The formation and transformation of the pharyngeal arch arteries in the mouse embryo, from 8.5 to 13 days of gestation (DG), was observed using scanning electron microscopy of vascular casts and graphic reconstruction of 1-µm serial epoxy-resin sections. Late in 8.5,9DG (12 somites), the paired ventral aortae were connected to the dorsal aortae via a loop anterior to the foregut which we call the ,primitive aortic arch', as in the chick embryo. The primitive aortic arch extended cranio-caudally to be transformed into the primitive internal carotid artery, which in turn gave rise to the primitive maxillary artery and the arteries supplying the brain. The second pharyngeal arch artery (PAA) appeared late in 9,9.5DG (16,17 somites), and the ventral aorta bent dorsolaterally to form the first PAA anterior to the first pharyngeal pouch by early in 9.5,10DG (21,23 somites). The third PAA appeared early in 9.5,10DG (21,23 somites), the fourth late in 9.5,10DG (27,29 somites), and the sixth at 10DG (31,34 somites). By 10.5DG (35,39 somites), the first and second PAAs had been transformed into other arteries, and the third, fourth and sixth PAAs had developed well, though the PAA system still exhibited bilateral symmetry. By 13DG, the right sixth PAA had disappeared, and the remaining PAAs formed an aortic-arch system that was almost of the adult type. [source]


    Carotid sonography and transesophageal echocardiography in patients with ischemic stroke or transient ischemic attack in the territory of the carotid artery

    JOURNAL OF CLINICAL ULTRASOUND, Issue 8 2006
    Marjatta Strandberg MD
    Abstract Purpose. To assess the benefit of combining carotid sonography and transesophageal echocardiography (TEE) for the evaluation of patients with stroke or transient ischemic attack (TIA) in the territory of the carotid artery. Methods. During a 2-year period in Turku University Hospital, consecutive in patients with stroke or TIA who were candidates for carotid endarterectomy and for oral anticoagulation were evaluated with carotid sonography for symptomatic moderate (50,69%) or severe (,70%) internal carotid artery (ICA) stenosis, and with TEE for potential cardiac sources of embolism. Results. In 20% (40/197) of patients, a severe symptomatic ICA stenosis and/or a major risk factor for a cardiac source of embolism were found. In 56% (110/197) of patients, a moderate or severe symptomatic ICA stenosis and/or a potential cardiac source of embolism were found, whereas 11% (21/197) of patients had both a moderate or severe symptomatic ICA stenosis and a potential cardiac source of embolism. Conclusions. This study suggests that the presence of a moderate or severe symptomatic ICA stenosis does not exclude the presence of a potential cardiac source of embolism and vice versa. Carotid sonography and TEE complement each other and are valuable diagnostic tools that should be recommended in patients with ischemic stroke or TIA in the territory of the carotid artery when they are candidates for carotid endarterectomy and for oral anticoagulation. © 2006 Wiley Periodicals, Inc. J Clin Ultrasound 34:374,379, 2006 [source]


    Accuracy of transcranial Doppler sonography for predicting cerebral infarction in aneurysmal subarachnoid hemorrhage

    JOURNAL OF CLINICAL ULTRASOUND, Issue 8 2006
    Ji-Yong Lee MD
    Abstract Purpose. To evaluate the accuracy of transcranial Doppler (TCD) sonography using different criteria for predicting cerebral infarction due to symptomatic vasospasm. Methods. We retrospectively evaluated the clinical and radiologic data of consecutive patients admitted with acute aneurysmal subarachnoid hemorrhage (SAH) in the anterior cerebral circulation between January 2001 and June 2002. TCD sonographic examinations were performed on alternate days up to 20 days after admission. Cerebral infarction was defined on CT as a new hypodensity in the vascular distribution with corresponding clinical symptoms. Vasospasm was diagnosed as mild or severe when TCD sonography revealed a mean blood flow velocity (MBFV) greater than 120 and 180 cm/s in the middle or anterior cerebral artery and in the intracranial part of the internal carotid artery, respectively. Results. A total of 93 patients with aneurysmal SAH in the anterior cerebral circulation were included. Vasospasm was demonstrated by TCD sonography in 60 patients (64.5%) and was shown via multivariable logistic regression analysis to be predictive of cerebral infarction (OR 3.11, 95% CI 1.46,6.59), with an 82.6% and 69.6% sensitivity, a 41.4% and 77.1% specificity, a 31.7% and 50.0% positive predictive value, and an 87.9% and 88.5% negative predictive value when the MBFV was greater than 120 and 180 cm/s, respectively. Conclusions. Vasospasm on TCD was found to be predictive of symptomatic cerebral infarction on CT, but its positive predictive value remained low despite the adoption of restrictive TCD criteria for vasospasm. © 2006 Wiley Periodicals, Inc. J Clin Ultrasound 34:380,384, 2006 [source]