Cerebral perfusion in patients with unilateral internal carotid artery occlusion by dual post-labeling delays arterial spin labeling imaging

BACKGROUND Global and regional cerebral blood flow(CBF)changes in patients with unilateral internal carotid artery occlusion(ICAO)are unclear when the dual post-labeling delays(PLD)arterial spin labeling(ASL)magnetic resonance imaging(MRI)technique is used.Manual delineation of regions of interest for CBF measurement is time-consuming and laborious.AIM To assess global and regional CBF changes in patients with unilateral ICAO with the ASL-MRI perfusion technique.METHODS Twenty hospitalized patients with ICAO and sex-and age-matched controls were included in the study.Regional CBF was measured by Dr.Brain's ASL software.The present study evaluated differences in global,middle cerebral artery(MCA)territory,anterior cerebral artery territory,and Alberta Stroke Program Early Computed Tomography Score(ASPECTS)regions(including the caudate nucleus,lentiform nucleus,insula ribbon,internal capsule,and M1-M6)and brain lobes(including frontal,parietal,temporal,and insular lobes)between ICAO patients and controls at PLD 1.5 s and PLD 2.5 s.RESULTS When comparing CBF between ICAO patients and controls,the global CBF in ICAO patients was lower at both PLD 1.5 s and PLD 2.5 s;the CBF on the occluded side was lower in 15 brain regions at PLD 1.5 s,and it was lower in 9 brain regions at PLD 2.5 s;the CBF in the contralateral hemisphere was lower in the caudate nucleus and internal capsule at PLD 1.5 s and in M6 at PLD 2.5 s.The global CBF in ICAO patients was lower at PLD 1.5 s than at PLD 2.5 s.The ipsilateral CBF at PLD 1.5 s was lower than that at PLD 2.5 s in 15 regions,whereas the contralateral CBF was lower at PLD 1.5 s than at PLD 2.5 s in 12 regions.The ipsilateral CBF was lower than the contralateral CBF in 15 regions at PLD 1.5 s,and in M6 at PLD 2.5 s.CONCLUSION Unilateral ICAO results in hypoperfusion in the global and MCA territories,especially in the ASPECTS area.Dual PLD settings prove more suitable for accurate CBF quantification in ICAO.

Anomalous course of the carotid arteries in the retrooesophageal space: An unusual cause of chest pain

The differential diagnosis of chest pain, one of the most frequent symptoms referred in the emergency department, includes cardiac and noncardiac causes and represents a difficult challenge for clinicians. Noncardiac chest pain can be defined as the recurrence of chest pain episodes indistinguishable from coronary events after the exclusion of a cardiac cause. It may be of musculoskeletal, pulmonary, gastroenterological, psychosomatic or neurological aetiology, oesophageal disorders representing the most common detectable cause. In this report we describe a rare case of chest pain which appeared after dinner, due to an oesophageal spasm caused by the anomalous course of the carotid arteries. The case is relevant because it describes a very uncommon variant of the physiological course of the carotid arteries, and because it is unusual that a retro thoracic vascular abnormality can be related to the appearance of chest pain without dysphagia. Chest pain which appears after dinner in our case is probably due to the unusual anatomic connection between oesophagus and carotid arteries that probably begins to make stronger when the patient undertakes the supine position: for that reason nocturnal chest pain promptly relieves after the assumption of orthostatic or semi orthostatic decubitus. In conclusion, in a patient who refers the sudden appearance of nocturnal chest pain certainly unrelated to coronary artery disease, the physicians should consider the involvement of oesophageal system, maybe determined by vascular course abnormalities.

Ultrafast pulse wave velocity technique for evaluating changes of carotid artery elasticity in Hashimoto thyroiditis patients with euthyroidism

Objective To explore the value of ultrafast pulse wave velocity(UFPWV)technique for evaluating changes of carotid artery elasticity in Hashimoto thyroiditis(HT)patients with euthyroidism.Methods Conventional ultrasound and UFPWV for carotid artery were prospectively performed in 91 HT patients with euthyroidism(HT group)and 81 healthy subjects(control group).Clinical data and ultrasonic parameters were compared between groups.Spearman correlation analysis was performed to observe the correlations of carotid pulse wave velocity in end of systole(PWV-ES)with clinical indexes and other ultrasonic parameters in HT group.Multiple stepwise linear regression analysis was used to screen the independent impact factors of increased carotid PWV-ES in HT group.Results Significant differences of thyroid peroxidase antibody(TPOAb),thyroglobulin antibody(TgAb),total cholesterol(TC),low density lipoprotein and neutrophil-lymphocyte ratio(NLR)were found between groups(all P<0.05).The carotid PWV-ES in HT group was significantly higher than that in control group(P<0.05),while no significant difference of carotid artery intima-media thickness(CIMT)nor carotid pulse wave velocity in beginning of systole(PWV-BS)was found between groups(both P>0.05).Carotid PWV-ES in HT group was positively correlated with patients'age,body mass index,TPOAb,TC,triglyceride,NLR and CIMT(r=0.217—0.707,all P<0.05).Patients'age,TPOAb and NLR were all independent impact factors of increased carotid PWV-ES in HT patients with euthyroidism(all P<0.05).Conclusion UFPWV technique could be used to evaluate changes of carotid artery elasticity in HT patients with euthyroidism,among which PWV-ES was relatively sensitive.

Early diagnostic value of carotid artery ultrasound parameters combined with epicardial adipose layer thickness in coronary heart disease

BACKGROUND Coronary heart disease is associated with coronary atherosclerosis indicated by carotid intima-media thickness(CIMT)thickening and altered vascular elasticity.The epicardial adipose layer can secrete proinflammatory factors that promote the formation of coronary atherosclerosis.Thus,the epicardial fat layer thickness(EAT)may also predict coronary heart disease.AIM To determine the role of common carotid artery ultrasound parameters and EAT in the early diagnosis of coronary artery disease.METHODS Based on coronary angiography,patients with newly suspected coronary heart disease were divided into case(n=107)and control(n=41)groups.The carotid ultrasound parameters,including vascular stiffness(β),elastic coefficient(EP),pulse wave conduction velocity(PWV-β),CIMT,and EAT were compared between the case and control groups and among patients with different lesion numbers in the case group.Pearson correlation was used to evaluate the early diagnostic value of EAT,common carotid artery elasticity,and CIMT for coronary heart disease.RESULTS EP,β,PWV-β,CIMT,and EAT were significantly higher in the case group compared with the levels in the control group(all P<0.001).In the case group,lesions were detected in one vessel in 34 patients,two vessels in 38 patients,and three vessels in 35 patients.Within the case group,β,EP,PWV-β,CIMT,and EAT levels significantly increased with an increased number of lesions(all P<0.001).EAT positively correlated withβ,EP,PWV-β,and CIMT(all P<0.01).The area under the curve for diagnosing coronary heart disease using EAT combined with CIMT and carotid elasticity was 0.893,and the sensitivity and specificity were 0.890 and 0.837.CONCLUSION EAT correlated well with changes in carotid artery elasticity and CIMT in patients with coronary heart disease.The combination of EAT,carotid artery elasticity,and CIMT facilitates the early diagnosis of coronary heart disease.

Ultrasound Combined with CTA in Diagnosis of Painless Aortic Dissection Combined with Carotid Artery Active Thrombosis: A Case Report

Background: Aortic dissection (AD) is a relatively rare but dreadful illness, often accompanied by severe, sharp (or tearing) back pain or anterior chest pain, as well as acute hemodynamic compromise. Painless dissection has also been reported in rare cases and might be misdiagnosed due to its atypical symptoms leading to catastrophic outcomes. Case presentation: The patient was admitted to the hospital due to right limb weakness with speech inability for more than 10 hours. In the routine cardiac ultrasound examination, the avulsion intimal echo was found in the initial segment of the descending aorta. The rupture range was about 11 mm, and the lumen was separated into real and false lumen. Further computed tomography angiography (CTA) examination confirmed the major arterial dissection (De Bakey Type I). Conclusion: We report a case of painless aortic dissection with active carotid artery thrombosis diagnosed by ultrasound and CTA, and to improve the understanding of painless aortic dissection by reviewing relevant domestic and foreign literature.

Relationship between peripheral arterial disease, carotid intima-media thickness and C-reactive protein in elderly diabetic patients

Purpose: To study the association between carotid intima media thickness (CIMT) and high sensitivity CRP (hs-CRP) level as markers for PAD in elderly patients with DM. Subjects: A case-control study on 90 participants aged 60 years and older divided into 60 cases (30 patients with DM alone and 30 patients with DM and comorbidities) and 30 healthy controls. All were assessed by measuring CIMT, ankle brachial index (AB), and markers for cardiovascular disease such as high-sensitivity CRP (hs-CRP), total cholesterol (TC), triglycerides (TG), high density lipoprotein (HDL), and low density lipoprotein (LDL). Results: hs-CRP levels showed statistically significant difference being highest among patients with DM and comorbidities and lowest among controls (P < 0.001). Also, symptoms of PAD were significantly higher among cases than controls. ABI was able to detect PAD in many asymptomatic patients. Color changes were present in only 43.30% (n = 26) of positive PAD cases while delayed wound healing, claudication pain, rest pain, cold extremities, and trophic changes were present in 23.30% (n = 14), 16.71% (n = 10), 16.71% (n = 10), 45.00% (n = 27), and 21.7% (n = 13). Using logistic regression analysis revealed that DM, CIMT, and hs-CRP were independent predictors for PAD (OR = 4.194, 7.236, 1.003;P value = 0.044, 0.25, 0.031) after adjustment of other coronary risk factors such as sex, smoking, hypertension, TC, and TG. Conclusion: Diabetic elderly have higher prevalence of asymptomatic PAD thannon-diabetics using solely ABI. DM, CIMT, and hs-CRP are independent predictors for the occurrence of PAD. Hs-CRP levels are highest among diabetics with comorbidities.

Imageology of internal carotid artery siphon in nonarteritic anterior ischaemic optic neuropathy

AIM:To evaluate whether narrowing of internal carotid artery siphon(ICAS)may increase the risk of developing non-arteritic anterior ischaemic optic neuropathy(NAION).METHODS:Totally 30 consecutive patients who had unilateral NAION and 30 gender-matched control subjects were recruited in the present study.The diameter of ICAS of all the participants were measured using head-and-neck computed tomographic angiography(CTA).Color doppler flow imaging(CDI)was used to measure the haemodynamics parameters of ICAS and short posterior ciliary arteries(SPCAs)in all subjects.Comparison of parameters between the NAION patients and controls as well as between the two sides within the patients were performed.The correlation between the diameter of ICAS and NAION was analyzed.RESULTS:A comparison of parameters between the affected side of the NAION patients and the controls,including the diameter of ICAS,the resistance index(RI)of ICAS,the blood flow velocities of SPCAs and RI of SPCAs,showed significantly difference(P<0.01),while there was no significant difference in terms of the mean blood flow velocity(Vm)of ICAS;Similar results were found while comparing all the measurements of the affected and unaffected side of patients(P for RI of SPCAs<0.05).No marked difference was detected in nearly all parameters except for RI of ICAS and SPCAs between the unaffected side of the NAION patients and the controls(P<0.05).The diameter of ICAS were significantly positive correlated with both peak systolic velocity(PSV)of SPCAs and end diastolic velocity(EDV)of SPCAs in patients with NAION(r=0.514,P<0.01 and r=0.418,P<0.05,respectively).CONCLUSION:Narrowing of ICAS may increase the risk of developing NAION.

Should We Be Concerned? Comparison of Catheter and CT Angiogram for Arterial Distensibility at the Site of Carotid Stenosis during Catheter Angiography

Purpose: During catheter angiogram (CA) there is momentary increase in intravascular volume and pressure due to intra-arterial injection that can potentially cause vascular distention at the stenotic site, whereas on CT angiogram (CTA) is unlikely due to intravenous administration. Methods: CA and CTA of the carotid artery from 29 patients were retrospectively studied. CA and CTA were obtained for each patient. Curved sagittal MPRs mirroring the carotid artery on CA were used to measure the diameter at stenosis and at the distal lumen. Mural plaque calcium content was graded on axial CTAs. Results: Accounting for repeated measurements, the likelihood that the lumen diameter from CA will be larger than CTA was higher at stenosis than distal to it but the difference in lumen diameters at stenosis was similar to CTA. There is insufficient evidence that intra-arterial hand-injection during CA leads to underestimation of the degree of stenosis. Percentage stenosis using the NASCET criteria differed between the 3 measurements, post hoc analysis showed significant difference between CA and axial CTA (p p > 0.99). The difference in lumen diameter did not depend on our calcium grading (p = 0.484). Conclusions: There is insufficient evidence to suggest that intra-arterial hand-injection contributes to vessel distention and underestimation of percent stenosis during CA in this study. Mural plaque calcium does not affect the degree of stenosis on CTA.

Bilateral Carotid Aneurysms Secondary to Catastrophic Antiphospholipid Syndrome in a Patient with Differential Diagnosis of Polyarteritis Nodosa

Background: Extracranial Carotid Artery Aneurysm is considered a therapeutic and diagnostic challenge. In an unprecedented way in the literature, we describe an aneurysm originating from the Catastrophic Antiphospholipid Syndrome. Case Presentation: A 25-year-old male patient came to the Emergency Room of the ABC University Hospital in Sao Bernardo do Campo referring to bilateral neck pain for 1 month, associated with carotid aneurysms. Due to the severity and urgency of the clinical condition, immediate surgical therapy was performed without a definitive etiological diagnosis. The initial morphological analysis of the carotid artery suggested a diagnosis of Polyarteritis Nodosa. After anamnesis, physical examination, the use of a specific primary vasculitis algorithm, and a review of the pathological anatomy was requested, which showed bilateral carotid aneurysms secondary to catastrophic antiphospholipid syndrome. Conclusion: It remains evident that Extracranial Carotid Artery Aneurysm-related morbidity and mortality caused by Catastrophic Antiphospholipid Syndrome are influenced by a quick and correct diagnosis.

经颅多普勒超声微栓子监测评估PAS治疗颈动脉颈段易损斑块疗效的观察

目的探讨经颅多普勒超声(TCD)微栓子监测评估PAS(抗氧化、抗血小板、调脂治疗)治疗颈动脉颈段易损斑块的疗效。方法收集中国人民解放军联勤保障部队第九一〇医院2019年7月至2021年7月收治的采用PAS疗法进行治疗的颈动脉颈段易损斑块患者作为研究组(46例)。选取2015年6月至2019年6月该院收治的仅采用AS疗法(抗血小板、调脂治疗)治疗的颈动脉颈段易损斑块患者作为对照组(38例)。对2组患者治疗前后进行TCD微栓子监测,并评估斑块稳定性。结果治疗后研究组共检测出微栓子信号(MES)阳性患者1例,对照组共检测出MES阳性患者6例(P<0.05)。治疗后颈动脉内膜中层厚度(IMT)研究组低于对照组(P<0.05)。研究组治疗后IMT明显低于治疗前(P<0.05),对照组治疗前后IMT无明显变化(P>0.05)。随访1年,研究组缺血事件发生率显著低于对照组(P<0.05),且发生急性脑梗死患者的卒中严重程度轻于对照组(P<0.05)。研究组出现3例消化系统不良反应,不影响治疗及预后。结论PAS治疗颈动脉颈段易损斑块,有助于提高斑块稳定性,可以降低卒中发生风险,减轻卒中严重程度。

Assessment of neovascularization within carotid plaques in patients with ischemic stroke

AIM:To assess neovascularization within human ca-rotid atherosclerotic soft plaques in patients with isch-emic stroke.METHODS:Eighty-one patients with ischemic stroke and 95 patients without stroke who had soft athero-sclerotic plaques in the internal carotid artery were studied.The thickest soft plaque in each patient was examined using contrast-enhanced ultrasound.Time-intensity curves were collected from 5 s to 3 min after contrast injection.The neovascularization within the plaques in the internal carotid artery was evaluated using the ACQ software built into the scanner by 2 of the experienced investigators who were blinded to the clinical history of the patients.RESULTS:Ischemic stroke was present in 7 of 33 patients(21%) with grade Ⅰ plaque,in 14 of 51 pa-tients(28%) with grade Ⅱ plaque,in 26 of 43 patients(61%) with grade Ⅲ plaque,and in 34 of 49 patients(69%) with grade Ⅳ plaque(P < 0.001 comparing grade Ⅳ plaque with grade I plaque and with grade Ⅱ plaque and P = 0.001 comparing grade Ⅲ plaque with grade Ⅰ plaque and with grade Ⅱ plaque).Analysis of the time intensity curves revealed that patients with ischemic stroke had a significantly higher intensity of enhancement(IE) than those without ischemic stroke(P < 0.01).The wash-in time(WT) of plaque was signifi-cantly shorter in stroke patients(P < 0.05).The sensi-tivity and specificity for IE in the plaque were 82% and 80%,respectively,and for WT were 68% and 74%,respectively.There was no significant difference in the peak intensity or time to peak between the 2 groups.CONCLUSION:This study shows that the higher the grade of plaque enhancement,the higher the risk of ischemic stroke.The data suggest that the presence of neovascularization is a marker for unstable plaque.

An Integrated Analysis of Risk Factors of Cognitive Impairment in Patients with Severe Carotid Artery Stenosis

Objective To investigate cognitive dysfunction in patients with carotid artery stenosis(CAS) and potential risk factors related to cognitive-especially memory-dysfunction. Methods Forty-seven patients with carotid artery stenosis were recruited into our study cohort. The Mini-Mental State Examination(MMSE) and the Montreal Cognitive Assessment(MoCA) were adopted to assess cognitive function, the Wechsler Memory Scale(WMS) to assess memory function, high-resolution MRI and enhanced ultrasound to evaluate carotid plaques, and computed tomography perfusion(CTP) imaging to evaluate intracranial blood perfusion. Single-factor analysis and multiple-factor regression analysis were used to analyze potential risk factors of cognitive impairment. Results Mini-Mental State Examination test results showed that 22 patients had cognitive impairment, and MoCA test results showed that 10 patients had cognitive impairment. Analysis of various risk factors indicated that the average memory quotient of female patients was higher than that of males(P = 0.024). The cognitive and memory performance of those with an educational background above high school were significantly better than those of participants with high school or lower(P = 0.045). Patients with abnormal intracranial perfusion performed worse on the MMSE test(P = 0.024), and their WMS scores were significantly lower(P = 0.007). The MMSE scores and the memory quotients were significantly lower in patients with a history of cerebral infarction(MMSE, P = 0.047, memory quotient score, P = 0.018). Conclusion A history of cerebral infarction and abnormal cerebral perfusion are associated with decline in overall cognitive function and memory in patients with carotid stenosis. Being female and having an educational background above high school may be protective factors in the development of cognitive dysfunction.

Subfoveal choroidal thickness and volume in severe internal carotid artery stenosis patients

AIM：To demonstrate the differences of retinal and choroidal structure changes in internal carotid artery（ICA） patients of China by enhanced-depth imaging optical coherence tomography（EDI-OCT）.METHODS：A retrospective review was conducted of 46 patients with a diagnosis of ICA stenosis greater than 65% on only one side（the opposite ICA Stenosis had less than 40% stenosis） from June 2015 through June 2016.All of the patients were combined with amaurosis fugax,but without any abnormality with other ocular examination.Thickness and volume of choroid and retina were manually measured by EDI-OCT.Differences were compared between ICA stenosis eyes and fellow eyes.RESULTS：There were no significant differences in the retinal thickness,macular retinal nerve fiber layer（m RNFL） thickness,inner thickness,or outer retinal thickness between the ICA Stenosis group and the control group（P=0.834,0.187,0.552,and 0.903,respectively）.The mean central choroidal thickness of the ICA Stenosis group was significantly lower than that of the control group（239.70±23.76 μm vs 257.46±22.13 μm,P〈0.001）.The percentage of ICA stenosis was significantly associated with the central choroidal thickness,central retinal thickness,foveal center choroidal volume,and foveal center retinal volume（r=0.854,0.678,0.729,and 0.785,respectively;P〈0.001）.There were no significant differences in the retinal and choroidal volume values in the 4 inner and 4 outer sectors between the two groups.CONCLUSION：The choroidal thickness in severe ICA stenosis eyes is lower than in fellow eyes.The choroidal thinning may occur before the retinal changes in patients with ocular ischemic syndrome.Evaluations of choroidal thickness may be useful to choose the optimal therapeutic schedule for ICA patients.

INSULIN RESISTANCE AND CAROTID ATHEROSCLEROSIS IN 221 PATIENTS WITH POTENTIAL HYPERGLYCEMIA

Objective To investigate the relationship between insulin resistance and carotid atherosclerosis in patients with potential hyperglycemia. Methods A total of 221 patients were recruited among those with potential hyperglycemia. All participants underwent physical examination, medical history interview, and 75 g oral glucose tolerance test. Venous blood was sampled for measurement of insulin and cholesterol levels. The intima-media thickness (IMT) in bilateral common carotid arteries was observed by B-mode ultrasound. Insulin resistance index was calculated by homeostasis model assessment (HOMA-IR). Subjects were stratified in quintiles according to HOMA-IR values. Risk factors and atherosclerotic parameters were analyzed. Results With HOMA-IR value increase, incidence of impaired glucose tolerance, diabetes mellitus, hypertension, and coronary artery disease increased, the levels of triglyceride (TG), low density lipoprotein cholesterol (LDL-C), fasting plasma glucose, 2 hour plasma glucose, and fasting insulin increased as well, while the level of high density lipoprotein cholesterol (HDL-C) decreased. Meanwhile, all atherosclerotic parameters increased. Multivariate regression analysis showed that TG, total cholesterol, HDL-C, LDL-C levels, and ln(HOMA-IR) were related to IMT, hence were risk factors for IMT increase. Conclusion Insulin resistance is implicated in atherogenesis.

Comparison of invasive dynamic blood pressure between superior mesenteric artery and common carotid artery in rats

BACKGROUND: The purpose of this study was to identify the consistency of invasive dynamic blood pressure(BP) monitoring between the superior mesenteric artery(SMA) and the common carotid artery(CCA).METHODS: Eight male Sprague-Dawley rats were cannulated in SMA and CCA simultaneously for BP monitoring, respectively.The abdominal aorta was prepared for the induction of BP change through clamping/de-clamping by a microvascular clip.The dynamic BP monitoring was performed by a polygraph system.Systolic blood pressure(SBP), diastolic blood pressure(DBP), and mean arterial pressure(MAP) values would be recorded during different time periods: the baseline(T1), the increasing period after clamping(T2), the platform period during clamping(T3), the decreasing period after de-clamping(T4), and the final platform period(T5).Three trials were performed on each rat with 15-minute intervals between consecutive monitoring.RESULTS: Systolic BP showed no significant differences between SMA and CCA.However, significant difference was found in diastolic blood pressure except at T5(P=0.534).Mean arterial pressure of two arteries were significantly different only at T1(P=0.015).The strength of association was significantly high between BP measurements through SMA and CCA(P<0.001).The BlandAltman analyses showed that mean bias of MAP changed no more than 5 mmHg and standard deviation less than 8 mmHg during T2 and T4, respectively.CONCLUSION: The study indicates SMA might be an alternative site for invasive BP monitoring during abdominal aorta occlusion and release, especially in cerebrovascular-related research.

Comparison of ultrasound-measured properties of the common carotid artery to tobacco smoke exposure in a cohort of Indonesian patients

BACKGROUND: The purpose of this study was to use point-of-care ultrasound(POCUS) to investigate the relationship between tobacco smoke exposure and the characteristics of the common carotid artery(CCA). The effect of both primary and secondary smoking on CCA properties was evaluated.METHODS: We performed a prospective cross-sectional study across 20 primary care clinics in Bandung, West Java, Indonesia in July 2016. Point of care ultrasound was performed on a convenience sample of Indonesian patients presenting to clinic. The CCA wall stiffness and carotid intima-media thickness(CIMT) were measured during diastole and systole. These measurements were correlated with smoke exposure and cardiovascular disease.RESULTS: We enrolled 663 patients in the study, with 426 patients enrolled in the smoking category and 237 patients enrolled in the second-hand smoke category. There was an overall positive correlation with the measured lifestyle factors and the ultrasound-measured variables in the group of individuals who smoked. For all variables, age seemed to contribute the most out of all of the lifestyle factors for the positive changes in CIMT and CCA wall stiffness.CONCLUSION: Our data yielded correlations between CCA properties and cardiovascular risk, as well as between CIMT and arterial stiffness. We were also able to demonstrate an increase in thickness of the CIMT in patients who have been exposed by tobacco through the use of ultrasound. Further large scale studies comparing patients with multiple cardiac risk factors need to be performed to confi rm the utility of ultrasound fi ndings of cardiovascular disease and stroke.

Multidimensional modeling of the stenosed carotid artery: A novel CAD approach accompanied by an extensive lumped model

This study describes a multidimensional 3D/lumped parameter（LP） model which contains appropriate inflow/outflow boundary conditions in order to model the entire human arterial trees. A new extensive LP model of the entire arterial network（48 arteries） was developed including the effect of vessel diameter tapering and the parameterization of resistance, conductor and inductor variables. A computer aided-design（CAD） algorithm was proposed to effciently handle the coupling of two or more 3D models with the LP model, and substantially lessen the coupling processing time. Realistic boundary conditions and Navier-Stokes equations in healthy and stenosed models of carotid artery bifurcation（CAB） were used to investigate the unsteady Newtonian blood flow velocity distribution in the internal carotid artery（ICA）. The present simulation results agree well with previous experimental and numerical studies. The outcomes of a pure LP model and those of the coupled 3D healthy model were found to be nearly the same in both cases. Concerning the various analyzed 3D zones, the stenosis growth in the ICA was not found as a crucial factor in determining the absorbing boundary conditions.This paper demonstrates the advantages of coupling local and systemic models to comprehend physiological diseases of the cardiovascular system.

Endovascular treatment of a ruptured pseudoaneurysm of the internal carotid artery in a patient with nasopharyngeal cancer:A case report

BACKGROUND Radiation therapy(RT)for nasopharyngeal cancer can cause several complications.In rare cases,an internal carotid artery pseudoaneurysm can occur,which can be fatal.We report the experience of a nasopharyngeal cancer patient who underwent radiation therapy and subsequently developed a fatal pseudoaneurysm of the petrous internal carotid artery.CASE SUMMARY A 39-year-old man was diagnosed with nasopharyngeal cancer 2 years ago(American Joint Committee on Cancer Stage T3N2M0)and received concurrent chemoradiation therapy.He subsequently relapsed and received chemotherapy.One week after the 4th cycle of chemotherapy,he was admitted to the emergency room of our hospital because of massive epistaxis accompanied by a headache.A pseudoaneurysm of the petrous internal carotid artery was confirmed by digital subtraction angiography(DSA).Stent-assisted endovascular coil embolization was performed and complete occlusion was achieved.No pseudoaneurysm was observed on DSA after coil embolization;however,intermittent epistaxis was maintained even after coil embolization.After seven days,a diagnostic laryngoscopy was performed.Massive bleeding occurred after aspiration of the blood clot during the laryngoscopy and the patient died of hypovolemic shock.In this case,epistaxis may have been a sign of pseudoaneurysm;therefore,treatment such as embolization should be performed promptly,and careful management should be undertaken after treatment.CONCLUSION This case highlights a rare,serious complication of RT in nasopharyngeal cancer and how it should be recognized and treated.

Percutaneous cervical carotid artery access with stenting of the left internal carotid artery in an elderly patient

To describe the successful endovascular treatment in a nonagenarian with symptomatic internal carotid artery stenosis using direct carotid artery access. An independent 98 year-old man was admitted to our hospital for symptoms of progressive weakness with disorientation and dysphasia. Carotid Duplex ultrasonography was performed which revealed a totally occluded right internal carotid artery and high grade stenosis of the left internal carotid artery by velocities of 608/240 cm/sec. The patient refused surgical endarterectomy and thus he was referred for carotid artery stenting. Using the femoral artery approach and multiple catheter techniques, access to the common carotid artery could not be accomplished safely. The procedure was aborted and he was therefore brought back to the catheterization laboratory the following day for direct carotid access. Carotid artery stenting was accomplished by using of a 6F sheath percutaneously in the left common carotid, cerebral protection device (CPD) and a Nitinol stent. The patient was discharged the following day without complications. At 14 months follow-up the patient is functional and independent without recurrence of symptoms. Carotid artery stenting via direct access can be accomplished in patients when the femoral artery approach is anatomically prohibitive. In this case of advanced age and the patient’s refusal for surgery, direct carotid access was his only option.

Common carotid arterial thrombosis associated with ulcerative colitis

A 26-year-old woman with ulcerative colitis was transferred to our hospital with left hemiparesis due to cerebral infarction. Cervical ultrasonography and magnetic resonance imaging angiography revealed thrombosis at the right common carotid artery and the right internal carotid artery. Antithrombotic and anticoagulant therapies were commenced. After about 2 wk of the treatment, the frequency of her diarrhea increased. She underwent emergency subtotal colectomy, but 10 d later an abundant hemorrhage from the remnant rectum occurred, so the remnant rectum was resected and an ileal pouch anal anastomosis was performed. Antithrombotic and anticoagulant therapies were continued, but neither her neurological status nor magnetic resonance imaging angiography findings showed subsequent changes. She was discharged 3 mon after operation. This is a rare case of common carotid arterial thrombosis occurring as a complication of ulcerative colitis, in which antithrombotic and anticoagulant therapies are considered to provoke a deterioration of the patient’s bowel disease.