Intracranial atherosclerotic disease(ICAD)is a common cause of ischaemic stroke and transient ischaemic attack(TIA)with a high recurrence rate.It is often referred to as intracranial atherosclerotic stenosis(ICAS),whe...Intracranial atherosclerotic disease(ICAD)is a common cause of ischaemic stroke and transient ischaemic attack(TIA)with a high recurrence rate.It is often referred to as intracranial atherosclerotic stenosis(ICAS),when the plaque has caused significant narrowing of the vessel lumen.The lesion is usually considered‘symptomatic ICAD/ICAS’(sICAD/sICAS)when it has caused an ischaemic stroke or TIA.The severity of luminal stenosis has long been established as a prognostic factor for stroke relapse in sICAS.Yet,accumulating studies have also reported the important roles of plaque vulnerability,cerebral haemodynamics,collateral circulation,cerebral autoregulation and other factors in altering the stroke risks across patients with sICAS.In this review article,we focus on cerebral haemodynamics in sICAS.We reviewed imaging modalities/methods in assessing cerebral haemodynamics,the haemodynamic metrics provided by these methods and application of these methods in research and clinical practice.More importantly,we reviewed the significance of these haemodynamic features in governing the risk of stroke recurrence in sICAS.We also discussed other clinical implications of these haemodynamic features in sICAS,such as the associations with collateral recruitment and evolution of the lesion under medical treatment,and indications for more individualised blood pressure management for secondary stroke prevention.We then put forward some knowledge gaps and future directions on these topics.展开更多
Microlenses fabricated using flexible elastomers can be tuned in focal length by application of controlled strain.By varying the strain azimuthally,the lenses may be deformed asymmetrically such that aberrations may b...Microlenses fabricated using flexible elastomers can be tuned in focal length by application of controlled strain.By varying the strain azimuthally,the lenses may be deformed asymmetrically such that aberrations may be controlled.This approach is used to tune the astigmatism of the tunable lenses,and it is shown that the generated wavefront may be accurately controlled.The lens presented here has an initial focal length of 32.6 mm and a tuning range of 12.3 mm for approximately 10%applied strain.The range of directly tunable Zernike polynomials representing astigmatism is about 3 mm,while the secondary lens errors,which cannot be tuned directly,vary only by about 0.2 mm.展开更多
Background The benefit of stroke thrombectomy for large infarct core still lacks robust randomised controlled studies.Aim To demonstrate the design of a clinical trial on endovascular therapy for acute anterior circul...Background The benefit of stroke thrombectomy for large infarct core still lacks robust randomised controlled studies.Aim To demonstrate the design of a clinical trial on endovascular therapy for acute anterior circulation large vessel occlusion(LVO)patients with large infarct core volume.Design ANGEL-ASPECT is a multicentre,prospective,randomised,open-label,blinded End-point trial to evaluate whether best medical management(BMM)combined with endovascular therapy improves neurological functional outcomes as compared with BMM alone in acute LVO patients with Alberta Stroke Program Early CT Score(ASPECTS)of 3-5 on non-contrast CT or infarct core volume range of 70-100 mL(defined as rCBF<30%on CT perfusion or ADC<620 on MRI)up to 24 hours from symptom onset or last seen well.Study outcomes The primary efficacy outcome is 90(±7)days modified Rankin Scale.Symptomatic intracranial haemorrhage within 48 hours from randomisation is the primary safety outcome.Discussion The ANGEL-ASPECT trial will screen patients with large infarct core(ASPECTS 3-5 or 70-100 mL)through image evaluation criteria within 24 hours and explore the efficacy and safety of endovascular therapy compared with BMM.展开更多
Background During the COVID-19 pandemic,decreased volumes of stroke admissions and mechanical thrombectomy were reported.The study’s objective was to examine whether subarachnoid haemorrhage(SAH)hospitalisations and ...Background During the COVID-19 pandemic,decreased volumes of stroke admissions and mechanical thrombectomy were reported.The study’s objective was to examine whether subarachnoid haemorrhage(SAH)hospitalisations and ruptured aneurysm coiling interventions demonstrated similar declines.Methods We conducted a cross-sectional,retrospective,observational study across 6 continents,37 countries and 140 comprehensive stroke centres.Patients with the diagnosis of SAH,aneurysmal SAH,ruptured aneurysm coiling interventions and COVID-19 were identified by prospective aneurysm databases or by International Classification of Diseases,10th Revision,codes.The 3-month cumulative volume,monthly volumes for SAH hospitalisations and ruptured aneurysm coiling procedures were compared for the period before(1 year and immediately before)and during the pandemic,defined as 1 March-31 May 2020.The prior 1-year control period(1 March-31 May 2019)was obtained to account for seasonal variation.Findings There was a significant decline in SAH hospitalisations,with 2044 admissions in the 3 months immediately before and 1585 admissions during the pandemic,representing a relative decline of 22.5%(95%CI−24.3%to−20.7%,p<0.0001).Embolisation of ruptured aneurysms declined with 1170-1035 procedures,respectively,representing an 11.5%(95%CI−13.5%to−9.8%,p=0.002)relative drop.Subgroup analysis was noted for aneurysmal SAH hospitalisation decline from 834 to 626 hospitalisations,a 24.9%relative decline(95%CI−28.0%to−22.1%,p<0.0001).A relative increase in ruptured aneurysm coiling was noted in low coiling volume hospitals of 41.1%(95%CI 32.3%to 50.6%,p=0.008)despite a decrease in SAH admissions in this tertile.Interpretation There was a relative decrease in the volume of SAH hospitalisations,aneurysmal SAH hospitalisations and ruptured aneurysm embolisations during the COVID-19 pandemic.These findings in SAH are consistent with a decrease in other emergencies,such as stroke and myocardial infarction.展开更多
背景和目的卒中治疗学术产业圆桌会议（Stroke Treatnlem Academic Industry Roundtable，STAIR）旨在通过学术界、产业界和监管机构之间的合作来推动急性卒中治疗发展。为了追求这一目标，根据大血管闭塞性卒中血管内治疗（endovascula...背景和目的卒中治疗学术产业圆桌会议（Stroke Treatnlem Academic Industry Roundtable，STAIR）旨在通过学术界、产业界和监管机构之间的合作来推动急性卒中治疗发展。为了追求这一目标，根据大血管闭塞性卒中血管内治疗（endovascular therapy，ET）获益的现有最新I级证据，制定出STAIR第9届会议专家共识推荐意见以概述将来ET领域的研究重点。方法推动该领域发展有3个主要方向：（1）建立在大血管闭塞性卒中患者中实施ET的医疗体系；（2）开发ET的辅助治疗手段；（3）探索ET在近期试验内未经过充分研究的患者人群中的临床获益情况。此外，还对诸如最佳试验设计和转归评价指标之类的方法学问题进行讨论。结果应对医疗体系发展策略进行调整以确保符合ET指征的患者能有机会得到治疗，同时能最大限度地缩短再灌注时间。辅助治疗手段包括神经保护、改善微循环／侧支循环以及围手术期管理。为了扩展适合ET的患者人群范围，将来的研究重点应是确定ET在那些超过传统治疗时间窗的患者、基线梗死核心区较大的患者以及其他重要亚组患者中的获益情况。结论大血管闭塞性卒中ET的研究重点是改进治疗体系、研究有效的辅助治疗手段以及探讨能否扩展ET的治疗指征。展开更多
卒中影像学研究组（StrokeImagingResearchGroup，STIR）、美国神经放射学学会和美国神经放射学学会基金会在过去1年多的时间时举办了一系列的工作会议，最后一次会议于2013年3月9日至10日在华盛顿召开的卒中治疗专业学术圆桌会议（Stro...卒中影像学研究组（StrokeImagingResearchGroup，STIR）、美国神经放射学学会和美国神经放射学学会基金会在过去1年多的时间时举办了一系列的工作会议，最后一次会议于2013年3月9日至10日在华盛顿召开的卒中治疗专业学术圆桌会议（Stroke Treatment Academy Industry Roundtable，STAIR）期间举行。展开更多
基金the General Research Fund(Reference Number 14106019)Early Career Scheme(Reference Number 24103122),Research Grants Council of Hong Kong+1 种基金Kwok Tak Seng Centre for Stroke Research and Interventionand Li Ka Shing Institute of Health Sciences.
文摘Intracranial atherosclerotic disease(ICAD)is a common cause of ischaemic stroke and transient ischaemic attack(TIA)with a high recurrence rate.It is often referred to as intracranial atherosclerotic stenosis(ICAS),when the plaque has caused significant narrowing of the vessel lumen.The lesion is usually considered‘symptomatic ICAD/ICAS’(sICAD/sICAS)when it has caused an ischaemic stroke or TIA.The severity of luminal stenosis has long been established as a prognostic factor for stroke relapse in sICAS.Yet,accumulating studies have also reported the important roles of plaque vulnerability,cerebral haemodynamics,collateral circulation,cerebral autoregulation and other factors in altering the stroke risks across patients with sICAS.In this review article,we focus on cerebral haemodynamics in sICAS.We reviewed imaging modalities/methods in assessing cerebral haemodynamics,the haemodynamic metrics provided by these methods and application of these methods in research and clinical practice.More importantly,we reviewed the significance of these haemodynamic features in governing the risk of stroke recurrence in sICAS.We also discussed other clinical implications of these haemodynamic features in sICAS,such as the associations with collateral recruitment and evolution of the lesion under medical treatment,and indications for more individualised blood pressure management for secondary stroke prevention.We then put forward some knowledge gaps and future directions on these topics.
基金This work was funded by the German Science Foundation within the framework of the Priority Program 1337 Aktive MikrooptikThe authors thank Philipp Muller and the Laboratory for Biomedical Technology at IMTEK for coating the master lenses.
文摘Microlenses fabricated using flexible elastomers can be tuned in focal length by application of controlled strain.By varying the strain azimuthally,the lenses may be deformed asymmetrically such that aberrations may be controlled.This approach is used to tune the astigmatism of the tunable lenses,and it is shown that the generated wavefront may be accurately controlled.The lens presented here has an initial focal length of 32.6 mm and a tuning range of 12.3 mm for approximately 10%applied strain.The range of directly tunable Zernike polynomials representing astigmatism is about 3 mm,while the secondary lens errors,which cannot be tuned directly,vary only by about 0.2 mm.
文摘Background The benefit of stroke thrombectomy for large infarct core still lacks robust randomised controlled studies.Aim To demonstrate the design of a clinical trial on endovascular therapy for acute anterior circulation large vessel occlusion(LVO)patients with large infarct core volume.Design ANGEL-ASPECT is a multicentre,prospective,randomised,open-label,blinded End-point trial to evaluate whether best medical management(BMM)combined with endovascular therapy improves neurological functional outcomes as compared with BMM alone in acute LVO patients with Alberta Stroke Program Early CT Score(ASPECTS)of 3-5 on non-contrast CT or infarct core volume range of 70-100 mL(defined as rCBF<30%on CT perfusion or ADC<620 on MRI)up to 24 hours from symptom onset or last seen well.Study outcomes The primary efficacy outcome is 90(±7)days modified Rankin Scale.Symptomatic intracranial haemorrhage within 48 hours from randomisation is the primary safety outcome.Discussion The ANGEL-ASPECT trial will screen patients with large infarct core(ASPECTS 3-5 or 70-100 mL)through image evaluation criteria within 24 hours and explore the efficacy and safety of endovascular therapy compared with BMM.
文摘Background During the COVID-19 pandemic,decreased volumes of stroke admissions and mechanical thrombectomy were reported.The study’s objective was to examine whether subarachnoid haemorrhage(SAH)hospitalisations and ruptured aneurysm coiling interventions demonstrated similar declines.Methods We conducted a cross-sectional,retrospective,observational study across 6 continents,37 countries and 140 comprehensive stroke centres.Patients with the diagnosis of SAH,aneurysmal SAH,ruptured aneurysm coiling interventions and COVID-19 were identified by prospective aneurysm databases or by International Classification of Diseases,10th Revision,codes.The 3-month cumulative volume,monthly volumes for SAH hospitalisations and ruptured aneurysm coiling procedures were compared for the period before(1 year and immediately before)and during the pandemic,defined as 1 March-31 May 2020.The prior 1-year control period(1 March-31 May 2019)was obtained to account for seasonal variation.Findings There was a significant decline in SAH hospitalisations,with 2044 admissions in the 3 months immediately before and 1585 admissions during the pandemic,representing a relative decline of 22.5%(95%CI−24.3%to−20.7%,p<0.0001).Embolisation of ruptured aneurysms declined with 1170-1035 procedures,respectively,representing an 11.5%(95%CI−13.5%to−9.8%,p=0.002)relative drop.Subgroup analysis was noted for aneurysmal SAH hospitalisation decline from 834 to 626 hospitalisations,a 24.9%relative decline(95%CI−28.0%to−22.1%,p<0.0001).A relative increase in ruptured aneurysm coiling was noted in low coiling volume hospitals of 41.1%(95%CI 32.3%to 50.6%,p=0.008)despite a decrease in SAH admissions in this tertile.Interpretation There was a relative decrease in the volume of SAH hospitalisations,aneurysmal SAH hospitalisations and ruptured aneurysm embolisations during the COVID-19 pandemic.These findings in SAH are consistent with a decrease in other emergencies,such as stroke and myocardial infarction.
文摘卒中影像学研究组（StrokeImagingResearchGroup，STIR）、美国神经放射学学会和美国神经放射学学会基金会在过去1年多的时间时举办了一系列的工作会议，最后一次会议于2013年3月9日至10日在华盛顿召开的卒中治疗专业学术圆桌会议（Stroke Treatment Academy Industry Roundtable，STAIR）期间举行。
