Morphological and functional observations of a novel model of retinal ischemia injury induced by bilateral carotid artery stenosis in mice

AIM:To investigate the features of retinal ischemic injuries in a novel mouse model with bilateral carotid artery stenosis(BCAS).METHODS:BCAS was induced with microcoil implantation in 6-8-week-old C57BL6 mice.Cerebral blood flow was monitored at 2,7,and 28d postoperatively.Retinal morphological changes were evaluated by fundus photography and hematoxylin-eosin staining.Fluorescein fundus angiography(FFA)was performed to detect retinal vascular changes and circulation.The levels of apoptosis,activation of neurogliosis,and expression of hypoxiainducible factor(HIF)-1αin the retina were assessed by Western blotting and immunofluorescence staining,followed by retinal ganglion cell(RGC)density detection.Additionally,electrophysiological examinations including photopic negative response(PhNR)was also performed.RESULTS:The mice demonstrated an initial rapid decrease in cerebral blood flow,followed by a 4-week recovery period after BCAS.The ratio of retinal artery and vein was decreased under fundus photography and FFA.Compared with the sham mice,BCAS mice showed thinner retinal thickness on day 28.Additionally,apoptosis was increased and RGC density was decreased mainly in peripheral retinal region.Neurogliosis was mainly located in the inner retinal layers,with a stable increase in HIF-1αexpression.The dark-adapted electroretinogram showed a notable reduction in the a-,b-,and oscillatory potential(OP)wave amplitudes between days 2 and 7;this gradually recovered over the following 4wk.However,the b-and OPwave amplitudes were still significantly decreased on PhNR examination on day 28.CONCLUSION:BCAS can result in relatively mild retinal ischemia injuries in mice,mainly in the inner layer and peripheral region.Our study provides a novel animal model for investigating retinal ischemic diseases.

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.

Evaluation of the Protégé^(TM) stent in the treatment of carotid artery stenosis with adjunctive use of a filter Embolic Protection Device (PROCAR)-one-month follow-up data on 77 patients

Objective The trial was designed to evaluate the safety and performance of the ev3 Protégé TM stent in the treatment of de novo or re-stenotic common and/or internal carotid artery stenoses with adjunctive use of a CE-marked filter embolic protection device.Methods This study was a prospective multi-center, single-arm trial. Between June and October 2003, 77 patients were enrolled in 8 investigational centers throughout Europe. The primary endpoint was the incidence of Major Neurological Events (MANE) through one month. Other endpoints were the ability to properly place the stent, and primary patency and MANE after six months. Eligible for the study were patients with a de novo or restenotic target lesion located in the common and/or internal carotid artery (>70% stenosis for asymptomatic and >50% stenosis for symptomatic patients). The ev3 Spider (Embolic Protection Filter was used in 75 of 77 cases. Results In 76 out of the 77 patients (99%), the stent could be successfully implanted with a residual stenosis ≤30% as criterion. Of the 74 patients that had a carotid ultrasound at one month follow-up, none had a re-stenosis of the target lesion. There were three MANEs during or immediately after the procedure (3.9%), two were major and one was a minor stroke. There were eight severe complications (9.1%); six of these happened during or immediately after the procedure and were related to the procedure, none was related to the device. They are resolved without sequelae. No deaths have occurred.Conclusions The Protégé stent is safe and performs well in the treatment of carotid artery stenosis. The technical success rate for placement of the Protégé stent as assessed by the residual stenosis post implant was very high and all stents were successfully deployed. The incidence of MANE was comparable with that in other recent carotid stent studies and still lower than standard CEA.

Correlating cognitive impairment with carotid atherosclerosis and carotid artery stenosis in patients with acute cerebral infarction

BACKGROUND：Studies have demonstrated that carotid atherosclerosis and carotid artery stenosis are closely associated with cognitive impairment in patients with and without clinically evident cerebrovascular disease. OBJECTIVE： To investigate the correlation between the degree of pathological changes in carotid atherosclerosis, carotid artery stenosis, and cognitive impairment in patients with acute cerebral infarction through the use of color Doppler imaging. DESIGN, TIME AND SETTING： The present concurrent, non-randomized, controlled experiment was performed at the Departments of Neurology and Ultrasound, Affiliated Hospital of North Sichuan Medical College between November 2006 and August 2007. PARTICIPANTS： Fifty-five patients with cerebral infarction, consisting of 35 males and 20 females, aged 50–82 years, were admitted to the hospital between November 2006 and August 2007 and recruited for this study. An additional 30 subjects consisting of 18 males and 12 females, aged 47–78 years, that concurrently received a health examination at the same hospital, were also included as normal controls. METHODS： Intima-media thickness （IMT）, plaque shape, size, and echo intensity of all subjects were detected by color Doppler flow imaging. Assessment criteria： IMT 〉 1.0 mm was considered to be intimal thickening, and IMT 〉 1.2 mm was determined to be formed atherosclerotic plaques. In the position of the largest plaque, the degree of carotid artery stenosis was determined by the following formula： （1-cross-sectional area of residual vascular luminal area/vascular cross-sectional area） × 100%. Less than 30% exhibited mild stenosis, 30%-40% moderate stenosis, and 〉 50% severe stenosis. MAIN OUTCOME MEASURES： IMT and the degree of carotid artery stenosis were evaluated by color Doppler flow imaging. The Mini-Mental State Examination （MMSE）, as well as the clinical memory scale, was compared between patients with cerebral infarction and normal controls. RESULTS： In the cerebral infarction group, IMT was increased, the degree of carotid artery stenosis was aggravated, and the MMSE and MQ scores of clinical memory scale were decreased. In particular, orientation of time and place, attention, calculation, and short-time memory were decreased. There were statistically significant differences in MMSE and MQ of clinical memory scale between patients with cerebral infarction and normal controls （P 〈 0.01）. The scores from the two scales were significantly lower in patients with cerebral infarction with carotid plaque subgroup compared to the cerebral infarction with no carotid plaque subgroup （P 〈 0.01）. The scores from the two scales were also significantly lower in patients with IMT 〉 1.0 mm, as well as moderate and severe carotid artery stenosis, compared to patients with IMT ≤ 1.0 mm, and normal and mild stenosis group （P 〈 0.05）. CONCLUSION： More severe atherosclerotic and carotid artery stenosis leads to more obvious cognitive impairment.

Effect of the Wall Thickness of the Vessel on FFRCT of Carotid Artery Stenosis

Fractional flow reserve(FFR)computed from computed tomography angiography(CTA),i.e.,FFRCT has been used in the clinic as a noninvasive parameter for functional assessment of coronary artery stenosis.It has also been suggested to be used in the assessment of carotid artery stenosis.The wall thickness of the vessel is an important parameter when establishing a fluid-structure coupling model of carotid stenosis.This work studies the effect of the vessel wall thickness on hemodynamic parameters such as FFRCT in carotid stenosis.Models of carotid stenosis are established based on CTA image data using computer-aided design software.It is assumed that the vessel wall is a linear elastic and isotropic material,and the blood an incompressible Newtonian fluid.Under the pulsating flow condition,ANSYS Transient Structural and CFX are used to simulate the blood flow of fluid-structure coupling in the carotid stenosis model in order to obtain hemodynamic parameters and the corresponding FFRCT.The results show that when the elastic modulus of the vessel wall is fixed,FFRCT will decrease with the increase of the wall thickness.Similarly,FFRCT will decrease with the increase of the elastic modulus when the wall thickness is fixed.The difference in hemodynamic parameters such as FFRCT,however,is relatively small if the stiffness of the two models are close.The results demonstrate that the effect of the vessel wall thickness,especially for a model with small elastic modulus,should be taken into account in using FFRCT for functional assessment of carotid stenosis.Moreover,under the linear elasticity and isotropic material assumptions,the stiffness coefficient may replace the elastic modulus and wall thickness as a parameter reflecting material property of the vessel wall in the carotid stenosis model.

Effect of cold weather on carotid artery stenosis and occlusion:A retrospective observational study

Objective:To investigate the effect of cold weather on carotid artery stenosis and occlusion.Methods:We conducted a retrospective observational study,in which 145 patients with carotid artery stenosis and occlusion were enrolled[115 men and 30 women;the mean age was 61.08 years(95%CI 59.27-62.88)].Patients were divided into the low-temperature group(n=98)(≤12℃)and the non-low temperature group(n=47)(>12℃).Clinical characteristics,blood pressure,National Institutes of Health Stroke Scale(NIHSS),blood fat,and blood viscositys were compared between the two groups.Correlation between NIHSS and mean daily temperature was analyzed.Results:There was no significant difference in the systolic and diastolic blood pressure between the two groups(P>0.05).The NIHSS score was slightly higher in the non-low temperature group compared to that of the low-temperature group(U=2984,P<0.01).Glycemia,cholesterol level,prothrombin time,fibrinogen,and International Normalized Ratio did not show any significant difference(P>0.05).Correlation analysis showed a very low positive and statistically significant correlation between ambient temperature and NIHSS score(r=0.18,P=0.029).Conclusion:Cold weather does not impact blood pressure,blood cholesterol,and coagulation factors of patients with carotid artery stenosis and occlusion.The neurological deficit is more severe in the non-low ambient temperature group.A potential relationship exists between ambient temperature and the level of neurological impairment.

Relationship between syndrome elements and anterior communicating artery opening in patients with smptomatic severe carotid artery stenosis/occlusion

Objective To study the relationship between syndrome elements and anterior communicating artery(ACoA)opening in patients with symptomatic severe carotid artery stenosis/occlusion.Methods Thirty-six patients with symptomatic severe carotid stenosis/occlusion were collected,including 26 patients with cerebral infarction and 10 patients with transient ischemic attack(TIA).Syndrome elements at five time points were collected.Computer tomography angiography(CTA)combined with magenic resonance angiograp(MRA)was used to evaluate the primary collateral circulation,and the prognosis and syndrome elements were statistically analyzed according to whether the ACoA was open or not.Results The ACoA was open more in the primary collateral circulation among patients with symptomatic severe carotid stenosis/occlusion.There was a statistically significant difference in national institute of health stroke scale(NIHSS)score improvement and good prognosis[the modified rankin scale(mRS)≤2]between the ACoA open group and the ACoA nonopen group on the 90th day(P<0.05).The proportion of patients with internal wind syndrome,blood stasis syndrome,Qi deficiency syndrome,and Yin deficiency syndrome in the ACoA non-open group was higher than that in the open group.Conclusion In the patients with severe carotid artery stenosis/occlusion,the group with presence of anterior communicating artery had better prognosis.The syndrome elements are more complex in the group without the presence of anterior communicating artery.The proportion of Qi deficiency syndrome was positively correlated with the non-opening of anterior communicating artery.The imaging evaluation of collateral circulation can provide guidance for syndrome differentiation and treatment.

CAS and CEA in the Treatment of Severe Internal Carotid Artery Stenosis

Objective:To explore the clinical value of carotid artery stent implantation(CAS)and carotid endarterectomy(CEA)in the treatment of patients with severe internal carotid artery stenosis.Methods:88 patients with severe carotid artery stenosis who underwent CAS and CEA in the First People's Hospital of Changde City(hereafter referred as "our hospital")from January 2018 to December 2020 were selected as the research objects and divided into CAS group(n=43)and CEA group(n=45).To understand the clinical application value and feasibility of the two surgical schemes by comparing the general situation,cerebral blood flow,MMSE scale,MOCA scale score and serum miR-145,IGF1R levels of the two surgical schemes.Conclusions:CAS and CEA in the treatment of patients with severe internal carotid artery stenosis,have good curative effect,can effectively improve the patient's cerebral blood flow,regulate serum miR-145,IGF 1R levels,promote the recovery of cognitive function,but relatively speaking,the incidence of stroke and hypotension after CAS is higher,and the incidence of hypertension after CEA is higher.

Fifty-eight cases of ocular ischemic diseases caused by carotid artery stenosis

Background The blood supply to the eye comes from the retinal central vascular system of the ophthalmic artery and the ciliary vascular system. The ophthalmic artery stems from the ipsilateral internal carotid artery. If occlusion or stenosis occurs in the carotid artery, the blood perfusion to the ophthalmic artery becomes insufficient, leading to signs and symptoms of anterior and posterior ocular ischemia. The objective of this study was to evaluate the clinical characteristics and risk factors of ocular ischemic diseases caused by carotid artery stenosis. Methods This study was a retrospective review of 145 patients with carotid artery stenosis. Fifty-eight patients who had symptoms of ocular ischemic disease caused by carotid artery stenosis formed group A and the other 87 patients who only had carotid artery stenosis formed group B. We analyzed the causes and course of disease, and relative risk factors, by comparing the two groups. Results The degree of carotid artery stenosis in group A was higher than that in group B. And group A had a greater decrease of ophthalmic artery flow. Male, hypertension, hyperlipidemia, and smoking were significantly related to carotid artery stenosis. Amaurosis fugax was the most common ocular symptom in group A. The ocular ischemic diseases mainly included ischemic optic neuropathy, central/branch retinal artery occlusion, ophthalmoplegia externa, and ocular ischemic syndrome. Conclusions Carotid artery stenosis correlates with ocular ischemic diseases. Ophthalmologists must observe for ocular symptoms, which were the onset symptoms in some patients.

Synchronous carotid endarterectomy and coronary artery bypass graft: Four case reports

BACKGROUND One of the major perioperative complications for coronary artery bypass graft(CABG)is stroke.The risk of perioperative stroke after CABG is approximately 2%.Carotid stenosis(CS)is considered an independent predictor of perioperative stroke risk in CABG patients.The optimal management of such patients has been a source of controversy.One of the possible surgical options is synchronous carotid endarterectomy(CEA)and CABG.Here,we have presented 4 cases of successful synchronous CEA and CABG.Our center’s experience with 4 cases of significant carotid artery stenosis,which were successfully managed with combined CEA and CABG,are detailed.The first case was a female who presented for CABG after a ST-elevation myocardial infarction.She had right internal carotid artery(ICA)occlusion and 90%left ICA stenosis.The second case was a male who was electively admitted for CABG.It was discovered that he had left ICA occlusion and 90%right ICA stenosis.The third case was a male with a history of stroke,two months prior to admission.He presented with non-ST-elevation myocardial infarction.Preoperatively,it was discovered that he had>90%right ICA stenosis.The final case was a male who was electively admitted for CABG.It was discovered that he had bilateral>90%ICA stenosis.We have also reviewed the current evidence and guidelines for managing CS in patients undergoing CABG.CONCLUSION Our case series demonstrated that synchronous CEA and CABG was safe.A multicenter study with additional patients is needed.It is necessary for clinicians to screen for CS in high-risk patients with features.

Evaluation of ischemic lesions after carotid artery stenting with diffusion-weighted imaging

BACKGROUND Almost 90%of cerebral thromboembolism cases are caused by atherosclerosis.Craniocervical atherosclerosis is often observed at the carotid bifurcation and is responsible for 20%-30%of all stroke cases.The course of atherosclerotic carotid artery stenosis varies depending on the grade of stenosis and characteristics of the plaque.Carotid artery stenting(CAS)can be used as a less invasive method in patients with symptomatic and asymptomatic high-grade carotid artery stenosis.Diffusion-weighted imaging(DWI)is an effective method for detection of silent or symptomatic acute ischemic lesions that may arise due to CAS or carotid endarterectomy.The number and volume of new ischemic lesions are determined using DWI.AIM To evaluate the number and volume of ischemic lesions and their cerebral parenchymal and vascular distribution after CAS using DWI.METHODS Forty-seven male(73.4%)and seventeen female(26.6%)patients(total,n=64)aged 42-84 years(mean 67.96±8.03 years)diagnosed with carotid stenosis between October 2006 and July 2012 were included in this retrospective study.Twelve of the cases(18.8%)were asymptomatic,while fifty-two(81.2%)were symptomatic.The area where the stenosis was highest was measured,and the stenosis rate was determined using the North American Symptomatic Carotid Endarterectomy Trial method.DWI of the cases was evaluated by two radiologists experienced in neuroradiology(B.A.with more than 15 years of experience,E.G.with more than 10 years of experience).Routine DWI examinations were carried out by a 1.5 T MR device 1 h before and after the operation.Since the ischemic lesions that developed in the first hour and in the follow-up period of 5-24 h were assumed to be due to CAS,all lesions within the first 24 h were considered as new ischemias.RESULTS In the present study,39 new ischemic lesions were detected in 20 cases.The average number of new lesions after all CAS operations was 0.62.They were mostly located in the occipital lobes,followed by the frontal and parietal lobes.These new ischemic lesions were most common in the middle cerebral artery territory,followed by the posterior cerebral artery territory and middle cerebral artery-posterior cerebral artery watershed areas.New lesions were found in 31.2%(20/64)of patients,including 17(26.5%)in ipsilateral and three(4.6%)in contralateral hemispheres.New bilateral lesions were detected in one case(1.5%).The average volume of the new ischemic lesions detected by the two observers was 1.10 cm³.The numbers of newly appearing ischemic lesions in DWI after CAS were significantly higher in cases where stenting was applied on the left side of the carotid artery and in cases where longer plaques(>1 cm)were responsible for the narrowing in symptomatic patients.The stenosis rate was low in the group with ulcerated plaques.CONCLUSION New ischemic lesions due to CAS appear mostly in the main arterial territory but they may also occur in watershed areas.

Transcervical access,reversal of flow and mesh-covered stents:New options in the armamentarium of carotid artery stenting

In the last 25 years, the very existence of carotid artery stenting(CAS) has been threatened on a number of occasions. The initial disappointing results that even lead to the discontinuation of an early randomized controlled trial have improved considerably with time. Novel devices, advanced stent and equipment technology, alternative types of access and several types of filters/emboli protecting devices have been reported to reduce stroke/death rates during/after CAS and improve CAS outcomes. The present review will provide a description of the various technology advances in the field that aim to reduce stroke and death rates associated with CAS. Transcervical access, reversal of flow and mesh-covered stents are currently the most promising tools in the armamentarium of CAS.

A Comprehensive Analysis of a Case of Internal Carotid Artery Stenting

With the development of science and technology and the continuous progress of interventional equipment,internal carotid artery stenting has become increasingly popular among patients in view of its advantages,which include high efficiency,minimally invasive,and fast postoperative recovery.It has grown importance as a surgical method for the treatment of severe internal carotid artery stenosis.This paper discusses a rare case of severe internal carotid artery stenosis and its management,where various types of pre-dilatation balloons were not able to be positioned in the stenting process.Relevant solutions have also been proposed in hope to provide a more theoretical and practical basis for clinical work.

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.

Association between neutrophil-to-lymphocyte ratio and major postoperative complications after carotid endarterectomy:A retrospective cohort study

BACKGROUND Carotid artery cross-clamping during carotid endarterectomy(CEA)may damage local cerebral perfusion and induce cerebral ischemia–reperfusion injury to activate local inflammatory responses.Neutrophil-to-lymphocyte ratio(NLR)is an indicator that reflects systemic inflammation.However,the correlation between NLR and complications after CEA remains unclear.AIM To investigate the association between NLR and major complications after surgery in patients undergoing CEA.METHODS This retrospective cohort study included patients who received CEA between January 2016 and July 2018 at Beijing Tiantan Hospital.Neutrophil and lymphocyte counts in whole blood within 24 h after CEA were collected.The primary outcome was the composite of major postoperative complications including neurological,pulmonary,cardiovascular and acute kidney injuries.The secondary outcomes included infections,fever,deep venous thrombosis,length of hospitalization and cost of hospitalization.Statistical analyses were performed using EmpowerStats software and R software.RESULTS A total of 224 patients who received CEA were screened for review and 206 were included in the statistical analyses;of whom,40(19.42%)developed major postoperative complications.NLR within 24 h after CEA was significantly correlated with major postoperative complications(P=0.026).After confounding factors were adjusted,the odds ratio was 1.15(95%CI:1.03–1.29,P=0.014).The incidence of major postoperative complications in the high NLR group was 8.47 times that in the low NLR group(P=0.002).CONCLUSION NLR is associated with major postoperative complications in patients undergoing CEA.

Acute carotid stent thrombosis:A case report and literature review

BACKGROUND Acute carotid stent thrombosis(ACST)is a rare but devastating complication in the carotid artery stenting(CAS)procedure.The aim of this article is to report a case and review cases of ACST reported in the literature,and investigate risk factors and management strategies for ACST.CASE SUMMARY We reviewed the treatment process of a patient with ACST after CAS.Then multiple databases were systematically searched to identify studies reporting ACST from 2005 to 2020.The demographic data,risk factors,treatment strategies,and prognosis were extracted and analyzed.CONCLUSION The reason for ACST is multifactorial.Proper patient selection,normative antiplatelet treatment,and perfect technical detail may decrease the incidence of ACST.Several treatment strategies such as thrombolysis,mechanical thrombectomy,and open surgery may be options for the treatment of ACST.Limited data have shown that carotid endarterectomy is effective with favorable results.

Improved circulation in ocular ischemic syndrome after carotid artery stenting

Ocular ischemic syndrome is a chronic ischemic eye disease including a series of ischemic ocular and brain syndromes caused by carotid artery occlusion or stenosis. Because of the different degrees of ischemia, clinical manifestations of ocular ischemic syndrome are diverse, and it is difficult to diagnose in the initial stage. The main strategy to treat ocular ischemic syndrome is elimination of carotid stenosis. We presented a patient who recovered dramatically after carotid artery stenting. The pre-stenting arm-retinal circulation time of the patient＇s left eye was prolonged, and a large amount of microaneurysm appeared at the posterior polar and mid-peripheral aspects of the left retina. The post-stenting arm-retinal circulation time of the left eve decreased to 16.3 seconds, and the microaneurvsm almost disappeared.

Perioperative Evaluation of Cerebral Blood Flow Using ^123I-labeled N-isopropyl-p-iodoamphetamine Single-Photon Emission Computed Tomography without Blood Sampling in Patients Who Underwent Carotid Artery Stenting

The evaluation of regional cerebral vascular reserve （rCVR） with single-photon emission computed tomography （SPECT） is useful for predicting cerebral hyperperfusion following carotid artery stenting （CAS） and carotidendarterectomy （CEA）.

Diabetes mellitus and adverse outcomes after carotid endarterectomy:A systematic review and meta-analysis

Background:There is still uncertainty regarding whether diabetes mellitus(DM)can adversely affect patients undergoing carotid endarterectomy(CEA)for carotid stenosis.The aim of the study was to assess the adverse impact of DM on patients with carotid stenosis treated by CEA.Methods:Eligible studies published between 1 January 2000 and 30 March 2023 were selected from the PubMed,EMBASE,Web of Science,CENTRAL,and ClinicalTrials databases.The short-term and long-term outcomes of major adverse events(MAEs),death,stroke,the composite outcomes of death/stroke,and myocardial infarction(MI)were collected to calculate the pooled effect sizes(ESs),95%confidence intervals(CIs),and prevalence of adverse outcomes.Subgroup analysis by asymptomatic/symptomatic carotid stenosis and insulin/noninsulin-dependent DM was performed.Results:A total of 19 studies(n=122,003)were included.Regarding the short-term outcomes,DM was associated with increased risks of MAEs(ES=1.52,95%CI:[1.15-2.01],prevalence=5.1%),death/stroke(ES=1.61,95%CI:[1.13-2.28],prevalence=2.3%),stroke(ES=1.55,95%CI:[1.16-1.55],prevalence=3.5%),death(ES=1.70,95%CI:[1.25-2.31],prevalence=1.2%),and MI(ES=1.52,95%CI:[1.15-2.01],prevalence=1.4%).DM was associated with increased risks of long-term MAEs(ES=1.24,95%CI:[1.04-1.49],prevalence=12.2%).In the subgroup analysis,DM was associated with an increased risk of short-term MAEs,death/stroke,stroke,and MI in asymptomatic patients undergoing CEA and with only short-term MAEs in the symptomatic patients.Both insulin-and noninsulin-dependent DM patients had an increased risk of short-term and long-term MAEs,and insulin-dependent DM was also associated with the short-term risk of death/stroke,death,and MI.Conclusions:In patients with carotid stenosis treated by CEA,DM is associated with short-term and long-term MAEs.DM may have a greater impact on adverse outcomes in asymptomatic patients after CEA.Insulin-dependent DM may have a more significant impact on post-CEA adverse outcomes than noninsulin-dependent DM.Whether DM management could reduce the risk of adverse outcomes after CEA requires further investigation.

Transcranial Doppler for detection of changes in ophthalmic artery blood flow

The ophthalmic artery （OA） is a main branch of the internal carotid artery （ICA）. Severe internal carotidartery stenosis or occlusion may not only affect the blood supply to the brain, but may also cause OA insufficiency, leading to ocular ischemia. Therefore, research on the hemodynamic changes in the OA in patients with ICA stenosis or occlusion has increasingly attracted more ophthalmologists＇ attention.1 Transcranial Doppler （TCD） is simple and noninvasive, has been widely used in the inspection of cerebrovascular disease,