ORCID Profile
0000-0003-2815-9198
Current Organisations
UNSW Sydney
,
Prince of Wales Hospital
,
Liverpool Hospital
,
Ingham Institute for Applied Medical Research
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Publisher: Cambridge University Press (CUP)
Date: 14-03-2019
DOI: 10.1017/CJN.2019.8
Abstract: Background: Endovascular thrombectomy (EVT) has shown efficacy in acute ischemic stroke (AIS) patients with infective endocarditis (IE). The possibility to undertake advanced histopathological clot analysis following EVT offers a new avenue to establish the etiological basis of the stroke – which is often labelled “cryptogenic.” In this paper, we present our findings from four consecutive patients with IE who underwent EVT following an AIS at our tertiary referral comprehensive stroke centre. Methods: Comprehensive histopathological analysis of clot retrieved after EVT, including morphology, was undertaken. Results: The consistent observation was the presence of dense paucicellular fibrinoid material mixed/interspersed with clusters of bacterial cocci. This clot morphology may be specific to septic embolus due to IE unlike incidental bacteraemia and could possibly explain the refractoriness of such clots to systemic thrombolysis. Conclusion: Detailed morphological and histopathological analysis of EVT-retrieved clots including Gram staining can assist in etiological classification of the clot. Understanding the composition of the clot may be of clinical value in early diagnostics and mapping treatment planning in IE.
Publisher: S. Karger AG
Date: 2021
DOI: 10.1159/000512105
Abstract: b i Background and Purpose: /i /b The benefit of bridging intravenous thrombolysis (IVT) in acute ischaemic stroke patients eligible for endovascular thrombectomy (EVT) is unclear. This may be particularly relevant where reperfusion is achieved with multiple thrombectomy passes. We aimed to determine the benefit of bridging IVT in first and multiple-pass patients undergoing EVT ≤6 h from stroke onset to groin puncture. b i Methods: /i /b We compared 90-day modified Rankin Scale (mRS) outcomes in 187 consecutive patients with large vessel occlusions (LVOs) of the anterior cerebral circulation who underwent EVT ≤6 h from symptom onset and who achieved modified thrombolysis in cerebral ischaemia (mTICI) 2c/3 reperfusion with the first pass to those patients who required multiple passes to achieve reperfusion. The effect of bridging IVT on outcomes was examined. b i Results: /i /b Significantly more first-pass patients had favourable (mRS 0–2) 90-day outcomes (68 vs. 42%, i /i = 0.001). Multivariate analysis showed an association between first-pass reperfusion and favourable outcomes (OR 2.25 95% CI 1.08–4.68 i /i = 0.03). IVT provided no additional benefit in first-pass patients (OR 1.17 CI 0.42–3.20 i /i = 0.76) however, in multiple-pass patients, it reduced the risk of disabling stroke (mRS ≥4) (OR 0.30 CI 0.10–0.88 i /i = 0.02) and mortality (OR 0.07 CI 0.01–0.36 i /i = 0.002) at 90 days. b i Conclusion: /i /b Bridging IVT may benefit patients with anterior circulation stroke with LVO who qualify for EVT and who require multiple passes to achieve reperfusion.
Publisher: Wiley
Date: 03-02-2023
Publisher: Frontiers Media SA
Date: 04-07-2018
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-2020
Publisher: BMJ
Date: 29-09-2017
DOI: 10.1136/NEURINTSURG-2017-013399
Abstract: Stent assisted coil embolization (SACE) of bifurcation aneurysms is challenging. Heterogeneous results have been achieved to date, but largely for laser cut stents. While braided stents offer multiple technical advantages, their long term efficacy has yet to be validated. To report the first long term 18 month results for the durability of bifurcation aneurysms treated with braided stents. Over a 4 year period, 59 consecutive patients with 60 bifurcation aneurysms underwent elective braided SACE across three Australian neurovascular centers. 17 of these aneurysms underwent T- or Y-shaped stent constructs. All patients had immediate, 6 month and 18 month clinical and radiological follow-up. Radiological assessment was made on modified Raymond–Roy occlusion scores while clinical assessment was based on the modified Rankin Scale. Subgroup analysis of 17 aneurysms treated with multi-stent constructs was conducted. 6 month follow-up data were available for 59 aneurysms and 18 month follow-up data for 58 aneurysms. Satisfactory aneurysm occlusion was achieved in 97% at inception and at 6 months, and 98% at 18 months. Good neurological outcomes were achieved in 95% at 18 months. Similar satisfactory results were achieved with the multi-stent construct cohort. Intraprocedural thromboembolic events were recorded in 5% and delayed events in 2%. Technical complications were found in 5%. All complication rate was 13%. Braided SACE was safe, efficacious, and durable at the long term 18 month follow-up, including for multi-stent constructs. Preliminary results indicate favorable clinical and radiological outcomes compared with laser cut stents.
Publisher: BMJ
Date: 15-12-2017
DOI: 10.1136/NEURINTSURG-2017-013402
Abstract: Preliminary short-term results for stent-assisted coil embolization (SACE) using woven/braided stents have been promising. However, evidence supporting mid- to long-term efficacy and durability is lacking. To report the long-term results for the durability of elective intracranial aneurysms treated with woven stents. Between May 2012 and May 2015, 98 consecutive patients with 103 aneurysms underwent elective woven SACE across three Australian neurovascular centres. All patients had immediate, 6- and 18-month clinical and radiological follow-up. Radiological assessment was performed with modified Raymond–Roy occlusion scores based on angiography results, while clinical assessment was based on the modified Rankin Scale. Six-month follow-up was available in 100 aneurysms, and an 18-month follow-up in 97 aneurysms. Total occlusion rates of 82% were achieved at inception, 82% at 6 months, and 90% at 18 months. Satisfactory occlusion with small neck remnants was present in 17% at inception, 16% at 6 months, and 9% at 18 months. Good neurological outcomes were achieved in 95% at 18 months. Intraprocedural thromboembolic events were recorded in 3% and delayed events in 1% (all in patients taking clopidogrel). Aneurysm recurrence occurred in one patient (1%). Technical complications occurred in 5%. The total complication rate was 10%. Woven SACE is safe, efficacious, and durable at long-term 18-month follow-up, with very low recurrence and re-treatment rates. Preliminary results appear better than those for traditional laser-cut stents.
Publisher: Public Library of Science (PLoS)
Date: 14-09-2023
Publisher: Wiley
Date: 12-11-2017
DOI: 10.1002/ACN3.500
Publisher: S. Karger AG
Date: 06-08-2021
DOI: 10.1159/000517929
Abstract: b i Background and Purpose: /i /b The short-term benefits of endovascular thrombectomy (EVT) for acute ischemic stroke (AIS) have been widely documented, yet there is limited evidence to show that this is sustained in the long term. We aimed to determine whether the benefit of EVT on functional outcome at 3 months is maintained at 12 months and the factors correlating with functional independence and quality of life. b i Methods: /i /b Data for analysis came from a prospective registry of consecutive patients undergoing EVT at a single Comprehensive Stroke Center (Oct 2018–Sep 2019). A phone interview was conducted for 12-month patient outcomes. Functional outcome was assessed by the modified Rankin Scale (mRS). Quality of life was determined by return to usual place of residence, work, or driving and calculation of a health utility index using the European Quality of Life-5 Dimensions questionnaire (EQ-5D-3L). b i Results: /i /b Of the 151 patients who underwent EVT during the study period, 12-month follow-up was available for 145 (96%). At 12 months, 44% ( i n /i = 64) of patients were functionally independent (mRS 0–2) compared to 48% at 3 months. Mortality at 12 months was 26% compared to 17% at 3 months. Significant predictors of functional independence at 12 months were younger age and lower baseline National Institutes of Health Stroke Scale. Better quality of life significantly correlated with return to usual place of residence and driving. b i Conclusion: /i /b Three-month functional independence was sustained at 12 months, indicating that EVT remains beneficial for patients with AIS in the longer term.
Publisher: OAE Publishing Inc.
Date: 2021
Publisher: Frontiers Media SA
Date: 20-03-2019
Publisher: SAGE Publications
Date: 07-07-2023
DOI: 10.1177/15910199231185632
Abstract: Balloon-assisted deployment/remodelling is a proven adjunctive technique for coil embolization of intracranial aneurysms, and it may be a helpful adjunct in delivering the Woven EndoBridge (WEB) device. To evaluate the safety, efficacy and feasibility of balloon-assisted WEB deployment in both ruptured and unruptured intracranial aneurysms in both typical and atypical locations. Patients who underwent treatment of ruptured and unruptured intracranial aneurysms with the BAWD technique were retrospectively identified from a prospectively maintained database at two neurointerventional centres. Patient demographics, aneurysm characteristics, technical procedure details, clinical and imaging outcomes were reviewed. Thirty-three aneurysms (23 women) were identified with a median age of 58 years. There were 15 (45.5%) ruptured aneurysms, 25 (64.3%) in the anterior circulation and 12 (36.4%) aneurysms having an atypical location for WEB treatment. The average aneurysm size was 6.8 mm (greatest dimension), 4.6 mm (height) and 4.5 mm (width), and 25 (75.8%) aneurysms had a wide neck morphology. One patient died (3.0%) secondary to a procedure-related complication, and there was no procedure-related permanent morbidity. Complete and adequate aneurysm occlusion on mid-term follow-up DSA was 85.2% and 92%, respectively. Balloon-assisted WEB deployment appears to be a safe and effective technique that may increase the utility of the WEB device. Further prospective studies on BAWD should be considered.
Publisher: Elsevier BV
Date: 03-2018
DOI: 10.1016/J.JOCN.2017.12.007
Abstract: Endovascular management of dural arteriovenous fistulas has become a mainstay of treatment. In particular, modern techniques have allowed greater fistula penetration and likelihood of complete obliteration. However, the efficacy of newer agents has not been quantified outside of predominantly small case reports and case series. Furthermore, the Australian experience with fistula embolization has yet to be reported in the literature. To this aim, we performed a retrospective review of our endovascular management of a large cohort of cranial dural arteriovenous fistulas in the liquid embolic era. This retrospective case series included ninety-six consecutive patients of any Cognard grade, treated between 2005 and 2016. Liquid embolic agents were used exclusively in eighty-three cases. The overall complete obliteration rate was 89.6% with a residual fistula rate of 2%, and complication rate of 8.3%. This Sydney, Australia cohort demonstrates excellent treatment effect and safety outcomes and thus supports the primary treatment of this condition by endovascular means.
Publisher: BMJ
Date: 30-11-2021
Abstract: Haematoma growth is common early after intracerebral haemorrhage (ICH), and is a key determinant of outcome. Tranexamic acid, a widely available antifibrinolytic agent with an excellent safety profile, may reduce haematoma growth. Stopping intracerebral haemorrhage with tranexamic acid for hyperacute onset presentation including mobile stroke units (STOP-MSU) is a phase II double-blind, randomised, placebo-controlled, multicentre, international investigator-led clinical trial, conducted within the estimand statistical framework. In patients with spontaneous ICH, treatment with tranexamic acid within 2 hours of onset will reduce haematoma expansion compared with placebo. A s le size of 180 patients (90 in each arm) would be required to detect an absolute difference in the primary outcome of 20% (placebo 39% vs treatment 19%) under a two-tailed significance level of 0.05. An adaptive s le size re-estimation based on the outcomes of 144 patients will allow a possible increase to a prespecified maximum of 326 patients. Participants will receive 1 g intravenous tranexamic acid over 10 min, followed by 1 g intravenous tranexamic acid over 8 hours or matching placebo. The primary efficacy measure is the proportion of patients with haematoma growth by 24±6 hours, defined as either ≥33% relative increase or ≥6 mL absolute increase in haematoma volume between baseline and follow-up CT scan. We describe the rationale and protocol of STOP-MSU, a phase II trial of tranexamic acid in patients with ICH within 2 hours from onset, based in participating mobile stroke units and emergency departments.
Publisher: Hindawi Limited
Date: 2013
DOI: 10.1155/2013/456156
Abstract: Hyperglycaemia with hemichorea (HGHC) is an unusual clinical entity that can be associated with corpus striatum hyperintensity on T1-weighted (T1W) magnetic resonance imaging (MRI) sequences. We report the utility of the susceptibility weighted image (SWI) sequence and the filtered phase SWI sequence in the imaging assessment of HGHC.
Publisher: BMJ
Date: 14-12-2018
DOI: 10.1136/NEURINTSURG-2018-014363
Abstract: The Pipeline Embolisation Device with Shield technology (PED-Shield) is suggested to have reduced thrombogenicity. This reduced thrombogenicity may make it possible to use safely in the acute treatment of aneurysmal subarachnoid haemorrhage (aSAH) on single antiplatelet therapy (SAPT). To evaluate the safety and efficacy of the off-label use of PED-Shield with SAPT for the acute treatment of aSAH. Patients who underwent acute treatment of ruptured intracranial aneurysms with the PED-Shield with SAPT were retrospectively identified from prospectively maintained databases at three Australian neurointerventional centres. Patient demographics, aneurysm characteristics, clinical and imaging outcomes were reviewed. Fourteen patients were identified (12 women), median age 64 (IQR 21.5) years. Aneurysm morphology was saccular in seven, fusiform in five, and blister in two. Aneurysms arose from the anterior circulation in eight patients (57.1%). Six (42.9%) patients were poor grade (World Federation of Neurological Societies grade ≥IV) SAH. Median time to treatment was 1 (IQR 0.5) day. Complete or near complete aneurysm occlusion (Raymond-Roy ) was achieved in 12 (85.7%) patients at the end of early-acute follow-up (median day 7 after SAH). Permanent, treatment-related morbidity occurred in one (7.1%) patient and one (7.1%) treatment-related death occurred. The use of a postoperative heparin infusion (n=5) was associated with a higher rate of all complications (80.0% vs 11.1%, p=0.023) and symptomatic complications (60% vs 0.0%, p=0.028). No symptomatic ischaemic or haemorrhagic complications were observed in the patients who did not receive a post-operative heparin infusion. Nine (64.3%) patients were functionally independent on discharge from the treatment centre. The PED-Shield may be safe to use in the acute treatment of ruptured intracranial aneurysms with SAPT. Further investigation with a formal treatment registry is needed.
Publisher: Elsevier BV
Date: 2018
DOI: 10.1016/J.JOCN.2018.10.114
Abstract: Two recent randomized controlled trials (RCTs) showed selected patients treated with endovascular thrombectomy (EVT) more than 6 h from acute ischemic stroke (AIS) onset had significant improvement in functional outcome at 90 days compared with standard care alone. Our aim is to determine the outcome and predictors of good outcome in AIS patients undergoing EVT with unknown-onset, or late presentation, stroke after 6 h from time last seen well, or witnessed stroke onset, at two Australian comprehensive stroke centres. A retrospective analysis of functional outcome and mortality at 90-days from a prospective cohort of 56 consecutive patients with unknown-onset, or late presentation, stroke with large vessel occlusion (LVO) in the anterior cerebral circulation undergoing EVT over a 15-month period (2016-2017). We evaluated factors which correlated with good functional outcome defined as a 90-day modified Rankin scale (mRS) 0-2. Recanalization times and symptomatic intracranial haemorrhage (sICH) rates were also examined. A good functional outcome was achieved in 35 patients (62%). Eight patients died (14%). Median time-to-recanalization was 7.6 h. SICH occurred in four patients (7%). Factors which predicted good 90-day functional outcome included baseline National Institutes of Health Stroke Scale (NIHSS) < 16, 24 h NIHSS < 10, baseline Alberta Stroke Program Early CT Score (ASPECTS) ≥ 8, pre-procedural CT perfusion imaging and LVO lesion location. This study shows good 'real world' outcomes, comparable to published RCTs, in patients with unknown-onset, or late presentation, stroke treated with EVT more than 6 h from stroke onset.
Publisher: Elsevier BV
Date: 12-2017
DOI: 10.1016/J.JOCN.2017.08.047
Abstract: Endovascular thrombectomy (EVT) has extended the conventionally accepted time window of treatment, from 4.5h (ECASS III trial) for intravenous thrombolysis, to 7.3h for EVT (HERMES collaboration). More recent evidence suggests EVT times could be extended to 24h in carefully selected patients (DAWN trial). Some patients present after these time windows with large areas of ischemia but little established infarction on imaging. They represent a major dilemma with much to gain from EVT but at theoretically higher risk of a poor outcome. We present a case of near-complete left M1 occlusion in which EVT achieved reperfusion 90h 41min after stroke onset with excellent clinical outcome. Current guidelines on treatment windows for EVT according to HERMES collaboration do not reflect in idual patient factors. In appropriate patients delayed EVT may give positive clinical outcomes.
Publisher: Wiley
Date: 02-02-2022
Publisher: BMJ
Date: 28-09-2016
DOI: 10.1136/NEURINTSURG-2016-012657.REP
Abstract: Subarachnoid hemorrhage secondary to rupture of a circumferential dissecting aneurysm continues to be a treatment dilemma. Vessel sacrifice, when possible, continues to be the safest option but in certain cases this is not possible due to lack of collateral supply. In such cases, coil assisted endovascular flow ersion has become a potential option but the requirement for dual antiplatelet therapy in an unsecured intracranial aneurysm continues to raise concern. We present a 48-year-old man with a World Federation of Neurological Surgeons grade 5 subarachnoid hemorrhage, secondary to a ruptured intradural left vertebral artery dissecting aneurysm, who was treated successfully with a pipeline embolization device with Shield technology using aspirin and a single intravenous loading dose of abciximab. To our knowledge, this is the first case of an acute flow ersion performed using only aspirin as the sole oral antiplatelet agent.
Publisher: BMJ
Date: 04-2020
DOI: 10.1136/BMJNO-2019-000030
Abstract: To assess the impact of interhospital transfer on the interplay between functional outcome, mortality, reperfusion rates and workflow time metrics in patients undergoing endovascular thrombectomy (EVT) for acute ischaemic stroke due to large vessel occlusion (LVO) in the anterior cerebral circulation. This is an analysis of a prospective database of consecutive patients undergoing EVT for LVO presenting between January 2017 and December 2018 at a single Australian comprehensive stroke centre (CSC). Patients presented directly or were transferred to the CSC from 21 sites across New South Wales and the Australian Capital Territory. The main outcome measures were rate of good 90-day functional outcome (modified Rankin Scale 0–2), successful reperfusion (Thrombolysis in Cerebral Infarction scale grade 2b or 3), symptomatic intracerebral haemorrhage (sICH) and 90-day mortality. Key workflow time metric milestones were examined. 154 of 213 (72%) patients were interhospital transfers. There was no significant difference in baseline characteristics including age, National Institutes of Health Stroke Scale score, intravenous thrombolysis administration or procedure time between transferred and direct presenters (all p .05). Transferred patients had worse 90-day functional outcome (39.6% vs 61.0%, OR 0.42, 95% CI 0.23 to 0.78), higher mortality (25.3% vs 6.8%, OR 4.66, CI 1.59 to 13.70) and longer stroke onset to treatment (groin puncture) time (298 min vs 205 min, p .01). Successful reperfusion rates and sICH were similar between the cohorts (96.8% vs 98.3%, and 7.8% vs 3.4%). Interhospital transfer is associated with longer stroke onset to treatment, worse 90-day functional outcome and higher mortality compared with patients presenting directly to the CSC.
Publisher: Springer Science and Business Media LLC
Date: 05-11-2021
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 06-2013
Location: No location found
No related grants have been discovered for Andrew Cheung.