Metric based virtual simulation training for endovascular thrombectomy improves interventional neuroradiologists' simulator performance.

OBJECTIVE: Metric based virtual reality simulation training may enhance the capability of interventional neuroradiologists (INR) to perform endovascular thrombectomy. As pilot for a national simulation study we examined the feasibility and utility of simulated endovascular thrombectomy procedures on a virtual reality (VR) simulator. METHODS: Six INR and four residents participated in the thrombectomy skill training on a VR simulator (Mentice VIST 5G). Two different case-scenarios were defined as benchmark-cases, performed before and after VR simulator training. INR performing endovascular thrombectomy clinically were also asked to fill out a questionnaire analyzing their degree of expectation and general attitude towards VR simulator training. RESULTS: All participants improved in mean total procedure time for both benchmark-cases. Experts showed significant improvements in handling errors (case 2), a reduction in contrast volume used (case 1 and 2), and fluoroscopy time (case 1 and 2). Novices showed a significant improvement in steps finished (case 2), a reduction in fluoroscopy time (case 1), and radiation used (case 1). Both, before and after having performed simulation training the participating INR had a positive attitude towards VR simulation training. CONCLUSION: VR simulation training enhances the capability of INR to perform endovascular thrombectomy on the VR simulator. INR have generally a positive attitude towards VR simulation training. Whether the VR simulation training translates to enhanced clinical performance will be evaluated in the ongoing Norwegian national simulation study.

Simulation-based team-training in acute stroke: Is it safe to speed up?

BACKGROUND: In acute ischemic stroke (AIS), rapid treatment with intravenous thrombolysis (IVT) is crucial for good clinical outcome. Weekly simulation-based team-training of the stroke treatment team was implemented, resulting in faster treatment times. The aim of this study was to assess whether this time reduction led to a higher proportion of stroke mimics (SMs) among patients who received IVT for presumed AIS, and whether these SM patients were harmed by intracranial hemorrhage (ICH). METHODS: All suspected AIS patients treated with IVT between January 1, 2015 and December 31, 2020 were prospectively registered. In 2017, weekly in situ simulation-based team-training involving the whole stroke treatment team was introduced. To analyze possible unintended effects of simulation training, the proportion of SMs among patients who received IVT for presumed AIS were identified by clinical and radiological evaluation. Additionally, we identified the extent of symptomatic ICH (sICH) in IVT-treated SM patients. RESULTS: From 2015 to 2020, 959 patients were treated with IVT for symptoms of AIS. After introduction of simulation training, the proportion of patients treated with IVT who were later diagnosed as SMs increased significantly (15.9% vs. 24.4%, p = .003). There were no ICH complications in the SM patients treated before, whereas two SM patients suffered from asymptomatic ICH after introduction of simulation training (p = 1.0). When subgrouping SMs into prespecified categories, only the group diagnosed with peripheral vertigo increased significantly (2.5% vs. 8.6%, p < .001). CONCLUSIONS: Simulation training of the acute stroke treatment team was associated with an increase in the proportion of patients treated with IVT for a suspected AIS who were later diagnosed with peripheral vertigo. The proportion of other SM groups among IVT-treated patients did not change significantly. No sICH was detected in IVT-treated SM patients.

Thrombectomy in large vessel occlusion stroke-Does age matter?

OBJECTIVES: Endovascular treatment (EVT) is the gold standard treatment for emergent large vessel occlusion (LVO). The benefit of EVT for emergent LVO in elderly patients (>80 years old) is still debated as they have been under-represented in randomized controlled trials. Elderly patients with an emergent LVO are a growing population warranting further study. MATERIALS & METHODS: We included 225 consecutive patients treated with EVT for LVO either in the anterior or posterior circulation. The clinical outcome was assessed using the National Institute of Health Stroke Scale (NIHSS). Long-term functional outcome was assessed using 90-day modified ranking scale (mRS). RESULTS: Neurological improvement: A five-year higher age predicted a 0.43 higher mean NIHSS score after EVT (p = .027). After adjusting for confounders (influencing variables), the association between age and post-interventional NIHSS was reduced and non-significant (p = .17). At discharge, a five-year higher age predicted a 0.74 higher mean NIHSS (p = .003). After adjusting for confounders this association was reduced and non-significant (p = .06). Long-term functional outcome: A five-year higher age predicted a 0.20 higher mRS at three months (p < .001). When adjusting for confounders this number was reduced to 0.16, yet still highly significant (p < .001). CONCLUSIONS: Age seems to have a minor role in predicting neurological improvement after EVT but has an impact on long-term functional outcome. The decision to perform or withhold EVT should therefore not solely be based on age.

Cost-effectiveness of a quality improvement project, including simulation-based training, on reducing door-to-needle times in stroke thrombolysis.

BACKGROUND: Rapid revascularisation in acute ischaemic stroke is crucial to reduce its total burden including societal costs. A quality improvement (QI) project that included streamlining the stroke care pathway and simulation-based training was followed by a significant reduction in median door-to-needle time (27 to 13 min) and improved patient outcomes after stroke thrombolysis at our centre. Here, we present a retrospective cost-effectiveness analysis of the QI project. METHODS: Costs for implementing and sustaining QI were assessed using recognised frameworks for economic evaluations. Effectiveness was calculated from previously published outcome measures. Cost-effectiveness was presented as incremental cost-effectiveness ratios including costs per minute door-to-needle time reduction per patient, and costs per averted death in the 13-month post-intervention period. We also estimated incremental cost-effectiveness ratios for a projected 5-year post-intervention period and for varying numbers of patients treated with thrombolysis. Furthermore, we performed a sensitivity analysis including and excluding costs of unpaid time. RESULTS: All costs including fixed costs for implementing the QI project totalled US$44 802, while monthly costs were US$2141. We calculated a mean reduction in door-to-needle time of 13.1 min per patient and 6.36 annual averted deaths. Across different scenarios, the estimated costs per minute reduction in door-to-needle time per patient ranged from US$13 to US$29, and the estimated costs per averted death ranged from US$4679 to US$10 543. CONCLUSIONS: We have shown that a QI project aiming to improve stroke thrombolysis treatment at our centre can be implemented and sustained at a relatively low cost with increasing cost-effectiveness over time. Our work builds on the emerging theory and practice for economic evaluations in QI projects and simulation-based training. The presented cost-effectiveness data might help guide healthcare leaders planning similar interventions.

Time-Based Decision Making for Reperfusion in Acute Ischemic Stroke.

Decision making in the extended time windows for acute ischemic stroke can be a complex and time-consuming process. The process of making the clinical decision to treat has been compounded by the availability of different imaging modalities. In the setting of acute ischemic stroke, time is of the essence and chances of a good outcome diminish by each passing minute. Navigating the plethora of advanced imaging modalities means that treatment in some cases can be inefficaciously delayed. Time delays and individually based non-programmed decision making can prove challenging for clinicians. Visual aids can assist such decision making aimed at simplifying the use of advanced imaging. Flow charts are one such visual tool that can expedite treatment in this setting. A systematic review of existing literature around imaging modalities based on site of occlusion and time from onset can be used to aid decision making; a more program-based thought process. The use of an acute reperfusion flow chart helping navigate the myriad of imaging modalities can aid the effective treatment of patients.

Clinical outcomes and safety profile of Tenecteplase in wake-up stroke.

BACKGROUND: Tenecteplase has probably pharmacological and clinical advantages in the treatment of acute ischemic stroke. There are lacking data about safety and efficacy of tenecteplase in wake-up stroke (WUPS). AIMS: To investigate safety and efficacy of tenecteplase compared to alteplase in WUPS patients included in NOR-TEST. METHODS: WUPS patients in NOR-TEST were included in the study based on DWI-FLAIR mismatch. Included patients randomly assigned (1:1) to receive intravenous tenecteplase 0.4 mg/kg (to a maximum of 40 mg) or alteplase 0.9 mg/kg (to a maximum of 90 mg). Neurological improvement was defined as 1) favorable functional outcome at 90 days modified Rankin Scale (mRS) of 0 or 1 and 2) neurological improvement measured with the National Institutes of Health Stroke Scale (NIHSS) of 4 points within 24 hours as compared to admission NIHSS or NIHSS 0 at 24 hours. RESULTS: Of 1100 patients from 13 stroke centers included in NOR-TEST, 45 were WUPS patients. Of these, 5 patients were stroke mimics and excluded. Of the remaining 40 patients (3.6%), 24 were treated with alteplase (60%). There was no difference in the number of patients achieving a good clinical outcome (mRS 0-1) in either treatment group. Patients treated with tenecteplase showed a better early neurological improvement (87.5% vs 54.2%, P = 0.027). No ICH was detected on MRI/CT 24-28 hours after thrombolysis. CONCLUSIONS: In WUPS patients treated in NOR-TEST, there was no difference in clinical outcomes at 90 days and no ICH events or deaths were observed in either alteplase- or tenecteplase-treated patients. Clinical Trial Registration-URL: https://www.clinicaltrials.gov. Unique identifier: NCT01949948.

Improving Stroke Care in Times of the COVID-19 Pandemic Through Simulation: Practice Your Protocols!

During the coronavirus disease 2019 (COVID-19) pandemic, infectious disease control is of utmost importance in acute stroke treatment. This is a new situation for most stroke teams that often leads to uncertainty among physicians, nurses, and technicians who are in immediate contact with patients. The situation is made even more complicated by numerous new regulations and protocols that are released in rapid succession. Herein, we are describing our experience with simulation training for COVID-19 stroke treatment protocols. One week of simulation training allowed us to identify numerous latent safety threats and to adjust our institution-specific protocols to mitigate them. It also helped our physicians and nurses to practice relevant tasks and behavioral patterns (eg, proper donning and doffing PPE, where to dispose potentially contaminated equipment) to minimize their infectious exposure and to adapt to the new situation. We therefore strongly encourage other hospitals to adopt simulation training to prepare their medical teams for code strokes during the COVID-19 pandemic.

Endovascular thrombectomy at low-volume centres: A Bayesian solution.

PURPOSE: Endovascular treatment (EVT) is traditionally performed by neurointerventional radiologists at tertiary medical centres imposing long transport ways to large vessel occlusion (LVO) stroke patients in rural areas. The purpose of this study is to evaluate the technical and clinical results over time at Stavanger University Hospital, a hospital without neurointerventional expertise, where trained general interventional radiologist performs EVT. METHODS: All patients with LVO stroke treated with EVT from May 2009 to December 2018 were included in the analysis. Technical outcome was measured by the modified treatment in cerebral ischaemia (mTICI) score, functional outcome by the modified Rankin Scale (mRS), complications registered. RESULTS: A total of 235 patients were treated with EVT. An angiographically good result (mTICI 2b or 3) could be seen in 66.7% of the patients treated the first year. In 2011, the year EVT with stent retrievers was introduced, the recanalization rate rose to 81.8%, and from 2014 onwards, it was stable around 80%. After introduction of aspiration together with stent retrievers in 2012, a good functional outcome (mRS 0-2) was obtained in >40% of the treated patients. In 2018, 61.1% of the patients got a good functional outcome. CONCLUSIONS: Endovascular treatment of LVO stroke performed by general vascular interventional radiologist in close collaboration with diagnostic neuroradiologists and stroke neurologists can achieve technical revascularization results and clinical patient outcomes in line with international recommendations, and the randomized controlled studies performed. This approach may help to introduce EVT in geographical areas where this service is lacking due to the absence of neurointerventional specialists.

Endovascular Thrombectomy in the Elderly: Do Radiological and Clinical Outcomes Differ from Those in Younger Patients? A Prospective Single-Center Experience.

OBJECTIVES: Endovascular treatment (EVT) has emerged as the gold standard therapy for stroke due to large vessel occlusion (LVO). There is however limited evidence to suggest that similar efficacy can be expected in elderly patients. We aimed to assess the efficacy and safety of EVT in elderly patients (aged > 80), comparing outcomes to younger patients (aged < 80). MATERIAL AND METHODS: A total of 195 patients with LVO stroke treated with EVT were included and dichotomized by age. We compared neurological improvement, clinical 90 day outcome, technical recanalization rates, procedure-related complications, and mortality in between the groups. RESULTS: Both groups showed equally marked neurological improvement. A favorable outcome modified Rankin Scale (mRS < 2) was seen in 28% of the elderly patients compared to 46% of the younger patients (p = 0.01). mRS 0-3 was seen in 46% of the elderly patients and 58% of the younger patients (p = 0.09). The rates of successful technical recanalization did not differ between the groups and there were no differences in procedural complication rates or incidence of symptomatic intracranial bleeding. Three-month mortality rates were however higher in the elderly group. CONCLUSIONS: EVT in the elderly resulted in equally notable neurological improvement as compared to younger patients. Although the elderly had a higher mortality rate and fewer favorable clinical outcomes at 3 month follow-up, a strict upper age limit for EVT seems unjustified.

Headache and MRI Changes after Endovascular Treatment of a Cerebral Aneurysm.

BACKGROUND: The main complications after endovascular therapy of intracranial aneurysms are aneurysm rupture and thromboembolic events. Yet, the widespread use of magnetic resonance imaging (MRI) in follow-up of these patients also demonstrates other, rarely known complications such as aseptic meningitis and foreign body reaction. CASE PRESENTATION: A small aneurysm in the right posterior communicating artery was treated with endovascular therapy in a 65 year old woman. Two weeks after successful interventional treatment, the patient developed a headache. On MRI performed five months after intervention, vasogenic edema was seen in the vascular territory of the right internal carotid artery. The edema and the symptoms diminished without specific treatment within a year. INTERPRETATION: The clinical and radiological presentation of this case are suggestive of a foreign body reaction, a treatable condition that radiologists and clinicians should be aware of.

The golden hour of acute ischemic stroke.

BACKGROUND: Acute Ischemic Stroke (AIS) treatment has been revolutionised in the last two decades with the increasing use of Intravenous Thrombolysis (IVT) and with the advent of Endovascular therapy (EVT). AIS treatment and outcome are time dependant and time saving measures are being implemented at every step of the treatment chain. These changes have resulted in lower treatment times in-hospital, but it is unclear if this translates into more patients being treated within 60 min of symptom onset - the Golden Hour. The clinical outcome of IVT therapy in this patient group was our secondary outcome. METHODS: From 2009 onwards, systematic changes were made to the AIS treatment chain leading to a dramatic decrease in Door-to-Needle (DTN) time. Analyses were performed on the number of these treatments year on year and their clinical outcomes within the Golden Hour at Stavanger University Hospital (SUS). RESULTS: Six-hundred and thirteen patients were included; seventy-three were treated within the Golden Hour. The percentage of total IVT treatments occurring in the Golden Hour rose from 2.2% in 2009 to 14.5% in 2015 (p = 0.006) with a high of 18.3% in 2012 (p < 0.001). All of these patients had a Median NIHSS of 0 at discharge, irrespective of age and pre-existing comorbidity. There was no incidence of any ICH and in-hospital mortality was only 2.7% in this group. DISCUSSION: The time from AIS symptom onset to treatment is filled with delays. Despite the inherence of some delays,significant efforts on the part of the pre- and in- hospital treatment chain have made IVT therapy within 60 min a possibility. The allocation and use of resources in the setting of rapid AIS treatment is warrantedand yields unprecedented results. CONCLUSIONS: Our study shows that improved treatment routines led to an increase in the number of patients treated within the Golden Hour. Treatment in the Golden Hour leads to excellent outcomes in all patients, irrespective of age and pre-existing comorbidity.

Endovascular stroke treatment in a small-volume stroke center.

INTRODUCTION: Our purpose was to evaluate the safety and efficacy of endovascular treatment (EVT) of stroke caused by large vessel occlusions (LVO) performed by general interventional radiologists in cooperation with stroke neurologists and neuroradiologists at a center with a limited annual number of procedures. We aimed to compare our results with those previously reported from larger stroke centers. PATIENTS AND METHODS: A total of 108 patients with acute stroke due to LVO treated with EVT were included. Outcome was measured using the modified Rankin scale (mRS) at 90 days. Efficacy was classified according to the modified thrombolysis in cerebral infarction (mTICI) scoring system. Safety was evaluated according to the incidence of procedural complications and symptomatic intracranial hemorrhage (sICH). RESULTS: Mean age of the patients was 67.5 years. The median National Institutes of Health Stroke Scale (NIHSS) on hospital admission was 17. Successful revascularization was achieved in 76%. 39.4% experienced a good clinical outcome (mRS<3). Intraprocedural complications were seen in 7.4%. 7.4% suffered a sICH. 21.3% died within 3 months after EVT. DISCUSSION: The use of general interventional radiologists in EVT of LVO may be a possible approach for improving EVT coverage where availability of specialized neurointerventionalists is challenging. EVT for LVO stroke performed by general interventional radiologists in close cooperation with diagnostic neuroradiologists and stroke neurologists can be safe and efficacious despite the low number of annual procedures.

Are the current MRI criteria using the DWI-FLAIR mismatch concept for selection of patients with wake-up stroke to thrombolysis excluding too many patients?

BACKGROUND: Up to 25% of stroke patients wake up with a neurological deficit, so called wake-up stroke (WUS). Different imaging approaches that may aid in the selection of patients likely to benefit from reperfusion therapy are currently under investigation. The magnetic resonance imaging (MRI) diffusion weighted imaging - fluid attenuated inversion recovery (DWI-FLAIR) mismatch concept is one proposed method for identifying patients presenting within 4.5 hours of the ischemic event. PURPOSE: To report our experience with the DWI-FLAIR mismatch concept for selection of wake-up stroke patients to be thrombolysed at our centre. MATERIAL AND METHODS: Patients treated with off label intravenous thrombolysis (IVT) for WUS at our centre during a 6.5-month period were included. We performed MRI including DWI and FLAIR in all patients at admission. Each MRI examination was rated as either DWI-FLAIR mismatch or match. National Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale were used to measure clinical outcome. Cerebral computed tomography (CT) or MRI was performed within 24 hours after thrombolysis to determine the presence of any intracranial haemorrhage (ICH). RESULTS: Ten patients treated with IVT for WUS were included. Four patients had a DWI-FLAIR mismatch and after IVT treatment the mean reduction in NIHSS in the DWI-FLAIR mismatch group was 4.0. In the DWI-FLAIR match group the mean reduction in NIHSS after IVT therapy was 4.8. None of the ten patients had any signs of ICH on follow-up imaging. CONCLUSIONS: In this small series DWI-FLAIR mismatch was not associated with worse outcome or ICH. This suggests that selecting WUS patients using DWI-FLAIR mismatch in clinical trials may exclude a large group of patients who might benefit.

Evaluation of the implementation of a rapid response treatment protocol for patients with acute onset stroke: can we increase the number of patients treated and shorten the time needed?

AIMS: This study aims to evaluate the implementation of a rapid response treatment protocol for patients presenting with acute onset ischemic stroke. Improvements of routines surrounding the admission and treatment of patients with intravenous thrombolysis (IVT), such as door-to-needle (DTN) times, and increasing the numbers of patients treated are discussed. METHODS: We conducted a retrospective analysis of all patients (n = 320) treated with IVT for acute onset ischemic stroke at the Stavanger University Hospital, Norway, between 2003 and 2012. In 2009, a succession of changes to pre- and intra-hospital routines were made as well as an improvement in the education of primary health care physicians, nurses and paramedics involved in the treatment of acute onset stroke patients (rapid response treatment protocol). Analyses of DTN times, onset-to-needle times and the number of patients treated per year were carried out to ascertain the effect of the changes made. The primary aim was to analyze DTN times to look for any changes, and the secondary aim was to analyze changes in the number of patients treated per year. RESULTS: In the years after the implementation of the rapid treatment protocol, we saw an improvement in the median DTN time with a decrease from 73 to 50 min in the first year (p = 0.03), a decrease of 45 min in the second year (p = 0.01) and a decrease of 31 min in the third year (p < 0.001). Similarly, an improvement in the number of patients treated per year was seen after enhancements in the treatment chain were made. A significant, 27-fold increase was shown when the number of patients treated in 2012 was compared with all patients treated in all years prior to the implementation of the rapid treatment protocol. CONCLUSIONS: The implementation of the rapid treatment protocol for acute onset ischemic stroke patients led to a significant decrease in the DTN time at our center. These improvements also produced an increase in the number of patients treated per year. The extension of the therapeutic window from 3 to 4.5 h for the use of intravenous recombinant tissue plasminogen activator also played a role in the increased treatment numbers.

The Norwegian tenecteplase stroke trial (NOR-TEST): randomised controlled trial of tenecteplase vs. alteplase in acute ischaemic stroke.

BACKGROUND: Alteplase is the only approved thrombolytic agent for acute ischaemic stroke. The overall benefit from alteplase is substantial, but some evidence indicates that alteplase also has negative effects on the ischaemic brain. Tenecteplase may be more effective and less harmfull than alteplase, but large randomised controlled phase 3 trials are lacking. The Norwegian Tenecteplase Stroke Trial (NOR-TEST) aims to compare efficacy and safety of tenecteplase vs. alteplase. METHODS/DESIGN: NOR-TEST is a multi-centre PROBE (prospective randomised, open-label, blinded endpoint) trial designed to establish superiority of tenecteplase 0.4 mg/kg (single bolus) as compared with alteplase 0.9 mg/kg (10% bolus + 90% infusion/60 minutes) for consecutively admitted patients with acute ischaemic stroke eligible for thrombolytic therapy, i.e. patients a) admitted <4½ hours after symptoms onset; b) admitted <4½ hours after awakening with stroke symptoms c) receiving bridging therapy before embolectomy.Randomisation tenecteplase:alteplase is 1:1. The primary study endpoint is favourable functional outcome defined as modified Rankin Scale 0-1 at 90 days. Secondary study endpoints are: 1) haemorrhagic transformation (haemorrhagic infarct/haematoma); 2) symptomatic cerebral haemorrhage on CT 24-48 hours; 3) major neurological improvement at 24 hours; 4) recanalisation at 24-36 hours; 5) death. DISCUSSION: NOR-TEST may establish a novel approach to acute ischaemic stroke treatment. A positive result will lead to a more effective, safer and easier treatment for all acute ischaemic stroke pasients.NOR-TEST is reviewed and approved by the Regional Committee for Medical and Health Research Ethics (2011/2435), and The Norwegian Medicines Agency (12/01402). NOR-TEST is registered with EudraCT No 2011-005793-33 and in ClinicalTrials.gov (NCT01949948).

Wernicke's Encephalopathy Mimicking Acute Onset Stroke Diagnosed by CT Perfusion.

Background. Metabolic syndromes such as Wernicke's encephalopathy may present with a sudden neurological deficit, thus mimicking acute onset stroke. Due to current emphasis on rapid admission and treatment of acute stroke patients, there is a significant risk that these stroke mimics may end up being treated with thrombolysis. Rigorous clinical and radiological skills are necessary to correctly identify such metabolic stroke mimics, in order to avoid doing any harm to these patients due to the unnecessary use of thrombolysis. Patient. A 51-year-old Caucasian male was admitted to our hospital with suspicion of an acute stroke due to sudden onset dysarthria and unilateral facial nerve paresis. Clinical examination revealed confusion and dysconjugate gaze. Computed tomography (CT) including a CT perfusion (CTP) scan revealed bilateral thalamic hyperperfusion. The use of both clinical and radiological findings led to correctly diagnosing Wernicke's encephalopathy. Conclusion. The application of CTP as a standard diagnostic tool in acute stroke patients can improve the detection of stroke mimics caused by metabolic syndromes as shown in our case report.

Neurointerventional treatment in acute stroke. Whom to treat? (Endovascular treatment for acute stroke: utility of THRIVE score and HIAT score for patient selection).

PURPOSE: Intra-arterial therapy (IAT) is used increasingly as a treatment option for acute stroke caused by central large vessel occlusions. Despite high rates of recanalization, the clinical outcome is highly variable. The authors evaluated the Houston IAT (HIAT) and the totaled health risks in vascular events (THRIVE) score, two predicting scores designed to identify patients likely to benefit from IAT. METHODS: Fifty-two patients treated at the Stavanger University Hospital with IAT from May 2009 to June 2012 were included in this study. We combined the scores in an additional analysis. We also performed an additional analysis according to high age and evaluated the scores in respect of technical efficacy. RESULTS: Fifty-two patients were evaluated by the THRIVE score and 51 by the HIAT score. We found a strong correlation between the level of predicted risk and the actual clinical outcome (THRIVE p = 0.002, HIAT p = 0.003). The correlations were limited to patients successfully recanalized and to patients <80 years. By combining the scores additional 14.3 % of the patients could be identified as poor candidates for IAT. Both scores were insufficient to identify patients with a good clinical outcome. CONCLUSIONS: Both scores showed a strong correlation to poor clinical outcome in patients <80 years. The specificity of the scores could be enhanced by combining them. Both scores were insufficient to identify patients with a good clinical outcome and showed no association to clinical outcome in patients aged ≥80 years.