Renal angiomyolipoma selective arterial embolization: Australian tertiary centre experience over 10 years.

INTRODUCTION: The purpose of this study is to evaluate the patient selection methods, treatment outcomes, complications, clinical and radiological follow-up after renal angiomyolipoma (AML) treatment with selective arterial embolization (SAE) in an Australian metropolitan tertiary centre. METHODS: This study presents a retrospective single-centre review of patients' medical records who underwent SAE for renal AML during the period of 1st January 2012 and 1st January 2023. RESULTS: A total of 32 SAE procedures for renal AML occurred during the study period. Three episodes were classified as emergency cases [9.38%] and the remaining 29 were treated electively. Mean AML size pre-treatment was 69.45 mm (range = 33-177; SD = 31.69). All AMLs demonstrated hyper-vascularity on contrast-enhanced cross-sectional imaging (arterial-phase enhancement characteristics and/or prominent tortuous feeding vessels) [n = 32; 100%] or an intralesional aneurysm or pseudoaneurysm [n = 12; 42.85%]. Periprocedural complications [n = 3; 9.38%] included: one intralesional haemorrhage after embolization, one vascular access site complication, and one lipiduria-associated urinary tract infection. No patients suffered a life-threatening complication, non-target embolization, deterioration in renal function or death following SAE. Re-treatment with SAE was performed in only three patients [10.71%]. Hospital mean length of stay was 1.58 days. Median durations of clinical and radiological follow-up post-treatment were 493 days (range = 104-1645) and 501 days (range = 35-1774), respectively. Follow-up imaging revealed AML total size reduction in all cases [mean = -17.17 mm; -26.51%] and 50% had obliteration of lesion hyper-vascularity after one episode of SAE. Outpatient clinical follow-up signifies that none of the patients included in the study have re-presented with lesion haemorrhage after successful SAE. CONCLUSION: In this study, renal AMLs were treated safely with a high degree of success by using SAE, and there were very low rates of periprocedural complications. Follow-up of patients after SAE treatment of renal AML should include both radiological (assessment for reduction in lesion vascularity and size) and clinical review in an outpatient clinic setting (either by an interventional radiologist or urologist).

Cerebrovascular Responses in a Patient with Lundberg B Waves Following Subarachnoid Haemorrhage Assessed with a Novel Non-Invasive Brain Pulse Monitor: A Case Report.

Subarachnoid haemorrhage (SAH) can trigger a range of poorly understood cerebrovascular responses that may play a role in delayed cerebral ischemia. The brain pulse monitor is a novel non-invasive device that detects a brain photoplethysmography signal that provides information on intracranial pressure (ICP), compliance, blood flow and tissue oxygen saturation. We monitored the cerebrovascular responses in a patient with Lundberg B waves following a SAH. The patient presented with a Fischer grade 4 SAH that required urgent left posterior communicating artery aneurysm coiling and ventricular drain insertion. On hospital day 4 oscillations or spikes on the invasive ICP were noted, consistent with Lundberg B waves. Brain pulse monitoring demonstrated concurrent pulse waveform features consistent with reduced brain compliance and raised ICP over both brain hemispheres. Oxygen levels also demonstrated slow oscillations correlated with the ICP spikes. Brief infrequent episodes of reduced and absent brain pulses were also noted over the right hemisphere. Our findings suggest that the brain pulse monitor holds promise for early detection of delayed cerebral ischemia and could offer insights into the vascular mechanisms at play.

Evaluation of techniques to improve a deep learning algorithm for the automatic detection of intracranial haemorrhage on CT head imaging.

BACKGROUND: Deep learning (DL) algorithms are playing an increasing role in automatic medical image analysis. PURPOSE: To evaluate the performance of a DL model for the automatic detection of intracranial haemorrhage and its subtypes on non-contrast CT (NCCT) head studies and to compare the effects of various preprocessing and model design implementations. METHODS: The DL algorithm was trained and externally validated on open-source, multi-centre retrospective data containing radiologist-annotated NCCT head studies. The training dataset was sourced from four research institutions across Canada, the USA and Brazil. The test dataset was sourced from a research centre in India. A convolutional neural network (CNN) was used, with its performance compared against similar models with additional implementations: (1) a recurrent neural network (RNN) attached to the CNN, (2) preprocessed CT image-windowed inputs and (3) preprocessed CT image-concatenated inputs. The area under the receiver operating characteristic curve (AUC-ROC) and microaveraged precision (mAP) score were used to evaluate and compare model performances. RESULTS: The training and test datasets contained 21,744 and 491 NCCT head studies, respectively, with 8,882 (40.8%) and 205 (41.8%) positive for intracranial haemorrhage. Implementation of preprocessing techniques and the CNN-RNN framework increased mAP from 0.77 to 0.93 and increased AUC-ROC [95% confidence intervals] from 0.854 [0.816-0.889] to 0.966 [0.951-0.980] (p-value = 3.91 × 10-12). CONCLUSIONS: The deep learning model accurately detected intracranial haemorrhage and improved in performance following specific implementation techniques, demonstrating clinical potential as a decision support tool and an automated system to improve radiologist workflow efficiency. KEY POINTS: • The deep learning model detected intracranial haemorrhages on computed tomography with high accuracy. • Image preprocessing, such as windowing, plays a large role in improving deep learning model performance. • Implementations which enable an analysis of interslice dependencies can improve deep learning model performance. • Visual saliency maps can facilitate explainable artificial intelligence systems. • Deep learning within a triage system may expedite earlier intracranial haemorrhage detection.

Tranexamic acid as a novel adjunct in the management of vessel perforation complicating Endovascular Clot Retrieval.

AIM: To assess the safety and utility of tranexamic acid (TXA) as an adjunct salvage therapy in iatrogenic vessel perforation complicating endovascular clot retrieval. Iatrogenic vessel perforation and extravasation are known and potentially fatal complications of endovascular clot retrieval (ECR). Various methods of establishing haemostasis post perforation have been reported. TXA is widely utilised intraoperatively to reduce bleeding in various surgical specialities. The use of TXA in endovascular procedures has not been previously described in the literature. METHODS: Retrospective case control study of all cases that underwent ECR. Cases where arterial rupture occurred were identified. Details of management and functional status at 3 months were recorded. Modified Rankin score (mRS) 0-2 was considered a good functional outcome. Comparison of proportions analysis was performed. RESULTS: Of 1378 cases of ECR, rupture complicated 36 (2.6%). TXA was administered in addition to standard care in 11 cases (31%). At 3 months, 4 of 11 cases (36%) where TXA was administered had a good functional outcome compared to 3 of 22 (12%) in the standard care group (P=0.09). Mortality at 3 months occurred in 4 of 11 cases (41.7%) where TXA was administered compared to 16 of 25 (64%) where it was not (P=0.13). CONCLUSION: Tranexamic acid administration in iatrogenic vessel rupture was associated with a lower mortality rate and a larger proportion of patients achieving a good functional outcome at 3 months. This effect trended towards but was not statistically significant. TXA administration was not associated with adverse effects.

Recent trends in publications in the Journal of Conservative Dentistry (2018-2022).

Aims and Objectives: The main goal of the present study is to analyze the pattern of article publication in the Journal of Conservative Dentistry (JCD) over 5 years. Materials and Methods: For the study, different parameters such as number of articles published, number of views per journal, types of articles (broadly categorized into editorial, case reports, reviews, and original research), citation of articles, subject of articles (conservative endodontics), and author institution mapping were assessed from the journal's official website. The results were tabulated and individually explained. Results and Conclusion: JCD has delivered broad-based and balanced coverage of endodontics and conservative dentistry between 2018 and 2022. The number of views and citations has increased over the years and JCD has begun to represent the global face of the Indian Association of Conservative Dentistry and Endodontics.

Sustainability in interventional radiology: are we doing enough to save the environment?

BACKGROUND: Healthcare waste contributes substantially to the world's carbon footprint. Our aims are to review the current knowledge of Interventional Radiology (IR) waste generation and ways of reducing waste in practice, to quantify the environmental and financial impact of waste generated and address green initiatives to improve IR waste management. METHODS: A systematic literature search was conducted in July 2022 using the Medline and Embase literature databases. The scope of the search included the field of IR as well as operating theatre literature, where relevant to IR practice. RESULTS: One-hundred articles were reviewed and 68 studies met the inclusion criteria. Greening initiatives include reducing, reusing and recycling waste, as well as strict waste segregation. Interventional radiologists can engage with suppliers to reformulate procedure packs to minimize unnecessary items and packaging. Opened but unused equipment can be prevented if there is better communication within the team and increased staff awareness of wasted equipment cost. Incentives to use soon-to-expire equipment can be offered. Power consumption can be reduced by powering down operating room lights and workstations when not in use, changing to Light Emitting Diode (LED) and motion sensor lightings. Surgical hand wash can be replaced with alcohol-based hand rubs to reduce water usage. Common barriers to improving waste management include the lack of leadership, misconceptions regarding infectious risk, lack of data, concerns about increased workload, negative staff attitudes and resistance to change. Education remains a top priority to engage all staff in sustainable healthcare practices. CONCLUSION: Interventional radiologists have a crucial role to play in improving healthcare sustainability. By implementing small, iterative changes to our practice, financial savings, greater efficiency and improved environmental sustainability can be achieved.

A Systematic Review of Neuropsychological Outcomes After Treatment of Intracranial Aneurysms.

BACKGROUND: Aneurysmal subarachnoid hemorrhage is a cause of profound morbidity and mortality. Its effects extend beyond functional neurological status to neurocognitive and psychological functioning. Endovascular treatment is becoming more prevalent after increasing evidence for its safety and efficacy; however, there is a relative paucity of evidence specific to neurocognitive status after treatment. OBJECTIVE: To assess and compare neuropsychological outcomes after the treatment of ruptured and unruptured intracranial aneurysms. METHODS: A systematic review of the literature was conducted searching for articles assessing the neuropsychological and cognitive outcomes after the treatment of ruptured and unruptured intracranial aneurysms. Inclusion criteria were English language, publication between January 2000 and October 2020, and discussion of neuropsychological outcomes in adequate detail. Outcomes were categorized into 8 domains: 5 Neurocognitive (Language, Executive Function, Complex Attention, Memory and Learning, and Perceptual motor function), Intelligence Quotient, Affect, and Quality of Life. RESULTS: Twenty-four articles were included comprising 2236 patients (924 surgical clipping, 1095 endovascular coiling, and 217 controls). These studies reported that most tests revealed no significant difference [n = 356/421 (84.56%)] between treatment modalities. More studies reported significantly superior test scores in the fields of language, executive function, and memory and learning after coiling [n = 53/421 tests (12.59%)] compared with clipping [n = 12/421 tests (2.85%)]. CONCLUSION: The current available data and published studies demonstrate a trend toward improved neurocognitive and psychological outcomes after endovascular treatment. Although these findings should be considered when deciding on the optimal treatment method for each patient, drawing definitive conclusions is difficult because of heterogeneity between patients and studies.

Clipping versus coiling: A critical re-examination of a decades old controversy.

BACKGROUND: Two major studies, The International Subarachnoid Aneurysm Trial and the Barrow Ruptured Aneurysm Trial, compare the long-term outcomes of clipping and coiling. Although these demonstrated coiling's initial benefits, rebleeding and retreatment rates as well as converging patient outcomes sparked controversy regarding its durability. This article will critically examine the available evidence for and against clipping and coiling of intracranial aneurysms. Critics of endovascular treatment state that the initial benefit seen with endovascular coiling decreases over the duration of follow-up and eventually functional outcomes of both treatment modalities are similar. Combined with the increased rate of retreatment and rebleeding, these trials reveal that coiling is not as durable and not as effective as a long-term treatment compared to clipping. Also, due to the cost of devices following endovascular treatment and prolonged hospitalization following clipping, the financial burden has been considered controversial. SUMMARY/KEY MESSAGES: Short-term outcomes reveal better morbidity and mortality outcomes following coiling. Despite the higher rates of retreatment and rebleeding with coiling, there was no significant change in functional outcomes following retreatment. Furthermore, examining more recent trials reveals a decreased rate of recurrence and rebleeding with improved technology and expertise. Functional outcomes deteriorate for both cohorts over time while recent results revealed improved long-term cognitive outcomes and levels of health-related quality of life after coiling in comparison to clipping. The expense of longer hospital stays following clipping must be balanced against the expense of endovascular devices in coiling.

Clinical Outcomes Following Rectal Artery Embolisation for the Treatment of Internal Haemorrhoids: A Systematic Review and Meta-Analysis.

OBJECTIVES: Haemorrhoidal disease (HD) is a common anorectal disorder which can substantially impair quality of life. Rectal artery embolisation (RAE) is a recently described technique for the management of HD, however, its clinical efficacy and safety are unclear at present. The objective of this systematic review and meta-analysis is to evaluate the clinical outcomes following RAE. METHODS: The PubMed, MEDLINE and EMBASE databases were searched for studies specifying the management of haemorrhoids with RAE from January 2000 to October 2021. Primary outcomes were: French bleeding score (FBS), Visual analogue scale (VAS) for pain, general quality of life (QoL) score, and the Goligher prolapse score (GPS). Secondary outcomes were technical success, clinical success, postoperative complications, and technical outcomes. A random-effects meta-analysis was conducted. Study heterogeneity was evaluated, and sensitivity analysis was performed. RESULTS: Thirteen eligible studies were identified including 381 patients. Rectal artery embolisation was associated with improvements in the FBS (mean difference [MD] 2.66; 95% confidence interval [CI] 2.10-3.23), VAS (MD 1.92; 95% CI 1.58-2.27) and QoL (MD 1.41; 95% CI 1.20-3.80), although the grade of internal haemerrhoids increased with uncertain clinical significance (MD 0.30; 95% CI 0.23-0.36). Technical success was achieved in almost all procedures (99%; 95% CI 94-100%) however clinical efficacy was lower (82%; 95% CI 73-89%). Procedural duration and radiation exposure were heterogeneous. No major complications occurred. CONCLUSION: RAE demonstrates early clinical efficacy with low rates of peri-procedural complications or morbidity. RAE is a promising addition to the treatment options available for HD and warrants ongoing research.

A Systematic Review and Meta-analysis of Patient Survival and Disease Recurrence Following Percutaneous Ablation of Pulmonary Metastasis.

BACKGROUND: Pulmonary metastasectomy has been widely adopted in the treatment of metastatic disease. In recent years image guided ablation has seen increased use in the treatment of thoracic malignancies. The objective of this study was to evaluate oncological outcomes following percutaneous ablation (PA) of pulmonary metastasis. METHODS: A comprehensive search of the PubMed, MEDLINE and EMBASE databases from January 2000 to August 2021 was performed to identify studies evaluating patient survival following ablation of lung metastasis. Pooled outcomes have been presented with a random effects model to assess primary outcomes of overall survival, progression free survival and 1-year local control. Secondary outcomes included procedural mortality, major complications, and the incidence of pneumothorax. RESULTS: A total of 24 studies were identified. The pooled median overall survival was 5.13 [95% confidence interval (CI): 4.37-6.84] years, and the 1-, 3-, 5-year progression free survival rates were 53%, 26% and 20% respectively. The 1-year local control rate was 91% (95%CI: 86-95%). Periprocedural mortality was rare (0%; 95%CI: 0-1%), as were major complications excluding pneumothorax (1%; 95%CI: 1-2%). Pneumothorax developed in 44% of ablation sessions, although only half of these required chest tube placement. Most patients were able to be discharged day one post-procedurally. CONCLUSION: PA demonstrates high overall, progression free and local tumour survival in patients with lung metastasis. Complications and mortality are also rare. Consideration of its use should be made in a tumour board meeting in conjunction with surgical and radiotherapy perspectives for targeted local control of metastases.

The Woven EndoBridge Device for the Treatment of Intracranial Aneurysms: Initial Clinical Experience within an Australian Population.

PURPOSE: Advances in endovascular technology have expanded the treatment options for intracranial aneurysms. Intrasaccular flow diversion is a relatively new technique that aims to disrupt blood inflow at the neck of the aneurysm, hence promoting intrasaccular thrombosis. The Woven EndoBridge device (WEB; MicroVention, Aliso Viejo, CA, USA) is an US Food and Drug Administration approved intrasaccular flow diverter for wide-necked aneurysms. We report the early interim clinical and radiological outcomes of patients with both ruptured and unruptured intracranial aneurysms (IAs) treated using the WEB device in an Australian population. MATERIALS AND METHODS: A retrospective analysis was done of patients with ruptured or unruptured IAs who received treatment with WEB across 5 Australian neuroendovascular referral centers between May 2017 and November 2020. Angiographic occlusion was assessed with time-of-flight magnetic resonance angiography. Complications were recorded and clinical outcomes were assessed using the modified Rankin scale at follow-up. RESULTS: In total, 66 aneurysms were treated in 63 patients, with successful deployment of the WEB device in 98.5% (n=65). Eighteen (26.9%) ruptured aneurysms were included. Failure of deployment occurred in a single case. Adjunct coiling and/or stenting was performed in 20.9% (n=14) cases. Sixty-two patients with 65 aneurysms using a WEB device were followed up (mean=9.1 months), and 89.4% of these had complete aneurysm occlusion while 1.5% remained patent. Functional independence was achieved in 93.5% of cases. CONCLUSION: Early results following the use of WEB devices in Australia demonstrate safety and adequate aneurysm occlusion comparable to international literature.

Nano eggshell-titanium-dioxide biocomposite in occluding opened dentine tubules.

It is of interest to synthesize Nano eggshell-titanium-dioxide (EB@TiO2) biocomposite and to evaluate its effectiveness in occluding opened dentine tubules. EB@TiO2 was synthesized and characterized using X-ray diffraction (XRD), and Transmission Electron Microscope (TEM). Sixteen simulated bovine dentine discs were prepared and randomly assigned into four groups according to the following treatment (n = 4): Group 1: No treatment; Group 2: eggshell powder; Group 3: EB@TiO2; and Group 4: GIC mousse. These were then, agitated in a solution of 1g powder and 40mL water for 3hours. Thereafter, each dentine discs from the respective groups were post-treated for 5 min with 2wt% citric acid to test their acid resistant characteristics. Scanning Electron Microscope (SEM) was used to observe the effectiveness of occluded dentine pre-treatment and post-treatment. The cytotoxicity of the synthesized EB@TiO2 was tested using NIH 3T3 assay. ANOVA was used to evaluate the mean values of the occluded area ratio and the data of MTS assay. This was followed by a multi-comparison test with Bonferroni correction (α = .05). The XRD confirmed that EB@TiO2 was successfully modified through ball-milling. The TEM revealed the presence of both spherical and irregular particle shape powders. The SEM result showed that EB@TiO2 could effectively occlude open dentine tubules. Equally, the result demonstrated that EB@TiO2 exhibited the highest acid resistant stability post-treatment. NIH 3T3 assay identified that EB@TiO2 had little effect on the NIH 3T3 cell line even at the highest concentration of 100µg/ml. This study suggests that the application of EB@TiO2 effectively occluded dentine tubules and the occlusion showed a high acid resistant stability.

Development of a machine learning-based real-time location system to streamline acute endovascular intervention in acute stroke: a proof-of-concept study.

BACKGROUND: Delivery of acute stroke endovascular intervention can be challenging because it requires complex coordination of patient and staff across many different locations. In this proof-of-concept paper we (a) examine whether WiFi fingerprinting is a feasible machine learning (ML)-based real-time location system (RTLS) technology that can provide accurate real-time location information within a hospital setting, and (b) hypothesize its potential application in streamlining acute stroke endovascular intervention. METHODS: We conducted our study in a comprehensive stroke care unit in Melbourne, Australia that offers a 24-hour mechanical thrombectomy service. ML algorithms including K-nearest neighbors, decision tree, random forest, support vector machine and ensemble models were trained and tested on a public WiFi dataset and the study hospital WiFi dataset. The hospital dataset was collected using the WiFi explorer software (version 3.0.2) on a MacBook Pro (AirPort Extreme, Broadcom BCM43x×1.0). Data analysis was implemented in the Python programming environment using the scikit-learn package. The primary statistical measure for algorithm performance was the accuracy of location prediction. RESULTS: ML-based WiFi fingerprinting can accurately predict the different hospital zones relevant in the acute endovascular intervention workflow such as emergency department, CT room and angiography suite. The most accurate algorithms were random forest and support vector machine, both of which were 98% accurate. The algorithms remain robust when new data points, which were distinct from the training dataset, were tested. CONCLUSIONS: ML-based RTLS technology using WiFi fingerprinting has the potential to streamline delivery of acute stroke endovascular intervention by efficiently tracking patient and staff movement during stroke calls.

Intracranial atherosclerotic disease and acute ischaemic stroke: A review of diagnosis and management.

Intracranial atherosclerotic disease is highly prevalent and a common cause of ischaemic stroke globally. With the increasing use of endovascular treatment for acute stroke management, computed tomography and magnetic resonance imaging have become an essential part of patient selection. In this review, we present the typical imaging findings of intracranial atherosclerosis and an overview of management as relevant to diagnostic and interventional radiologists.

CaRotid Artery Filtering Technique (CRAFT): A Technique for Carotid Artery Stenting with Intrinsic Embolic Protection.

PURPOSE: Carotid artery stenting (CAS) is an established treatment for symptomatic carotid artery stenosis as an alternative to carotid endarterectomy. A variety of techniques and devices have been devised to minimise periprocedural stroke risk using either proximal or distal embolic protection. This study presents a method of embolic protection during CAS-the CaRotid Artery Filtering Technique (CRAFT). MATERIALS AND METHODS: The CRAFT technique employs aspects of both proximal and distal embolic protection. The CASPER RX stent (MicroVention, Tustin, CA, USA), which is a double-layered, closed-cell, micromesh nitinol stent, is deployed across the carotid artery stenosis with the assistance of a FlowGate balloon guide catheter (Stryker Neurovascular, Fremont, CA, USA). The partially deployed stent acts as a distal filter while the balloon guide is deflated midway during stent deployment to prevent distal plaque embolisation, followed by completion of stent deployment and angioplasty. RESULTS: A total of 94 patients underwent CAS using the CRAFT technique between June 2016 and March 2021. Successful stent deployment was achieved in all patients. Preliminary results demonstrated acute stent occlusion in 6 patients (6.4%) and distal embolic stroke in 5 patients (5.3%). The median procedural fluoroscopy time was 34 minutes with an interquartile range of 22 to 55 minutes. CONCLUSION: The CRAFT technique of CAS presented by this study can be applied in the treatment of symptomatic carotid artery stenosis in both emergency and elective procedure settings with a high technical success and low distal embolic stroke risk.

Contemporary Treatment of Intracranial Blood Blister Aneurysms - A Systematic Review.

INTRODUCTION: Blood blister aneurysms (BBAs) are rare aneurysms affecting non-branched points of intracerebral arteries. Due to their small size and fragility, BBAs are prone to rupture, and can be challenging to diagnose and treat. Several treatment options have been suggested yet there is no consensus regarding the best modality to reduce morbidity and mortality. MATERIALS AND METHODS: A systematic review of the literature was conducted searching for articles discussing the treatment of BBAs. Inclusion criteria included: articles published between January 2010 and August 2020, English language, with each paper including at least 15 patients. Studies included required detailed reporting of patient demographics, treatment, and patient outcomes (including complications, recurrence, neurologic functional status, and mortality). RESULTS AND DISCUSSION: A total of 25 studies with 883 patients were included. Most were female (n = 594, 67.3%) and aneurysms were overwhelmingly located in the supraclinoid internal carotid artery (99%). Aneurysms were variable in size and mostly presented with subarachnoid haemorrhage. Endovascular treatment (n = 518, 58.7%) was more common than microsurgery (n = 365, 41.1%) while only 2 patients were managed conservatively. Complications were more common in patients treated microsurgically. Microsurgical procedures had an unfavorable outcome (mRS 4-6, GOS 1-3) rate of 27.8% (n = 100/360) while that of endovascular procedures was 14.7% (n = 70/477). Endovascular procedures had a lower mortality rate than microsurgical interventions (8.4% vs 11%). CONCLUSION: This review demonstrates that endovascular treatment of blood blister aneurysm has reduced morbidity and mortality when compared with microsurgical treatment. Small sample sizes and substantial study heterogeneity makes strong conclusions difficult.

Application of a computational model in simulating an endovascular clot retrieval service system within regional Australia.

INTRODUCTION: The global demand for endovascular clot retrieval (ECR) has grown rapidly in recent years creating challenges to healthcare system planning and resource allocation. This study aims to apply our established computational model to predict and optimise the performance and resource allocation of ECR services within regional Australia, and applying data from the state of South Australia as a modelling exercise. METHOD: Local geographic information obtained using the Google Maps application program interface and real-world data was input into the discrete event simulation model we previously developed. The results were obtained after the simulation was run over 5 years. We modelled and compared a single-centre and two-centre ECR service delivery system. RESULTS: Based on the input data, this model was able to simulate the ECR delivery system in the state of South Australia from the moment when emergency services were notified of a potential stroke patient to potential delivery of ECR treatment. In the model, ECR delivery improved using a two-centre system compared to a one-centre system, as the percentage of stroke patients requiring ECR was increased. When 15% of patients required ECR, the proportion of 'failure to receive ECR' cases for a single-centre system was 17.35%, compared to 3.71% for a two-centre system. CONCLUSIONS: Geolocation and resource utilisation within the ECR delivery system are crucial in optimising service delivery and patient outcome. Under the model assumptions, as the number of stroke cases requiring ECR increased, a two-centre ECR system resulted in increased timely ECR delivery, compared to a single-centre system. This study demonstrated the flexibility and the potential application of our DES model in simulating the stroke service within any location worldwide.