https://ogma.newcastle.edu.au/vital/access/ /manager/Index en-au 5 https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:35840 Wed 11 Dec 2019 09:40:13 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:31435 P < 0.001). For every millilitre of penumbra salvaged, 7.2 days of disability-adjusted life-year days were saved (ß = -7.2, 95% confidence interval, -10.4 to -4.1 days, P < 0.001). Each minute of earlier onset-to-treatment time resulted in a saving of 4.4 disability-free days after stroke (1.3-7.5 days, P = 0.006). However, after adjustment for imaging variables, onset-to-treatment time was not significantly associated with savings in disability-adjusted life-year days. Pretreatment perfusion computed tomography can (independently of clinical variables) predict significant gains, or loss, of disability-free life in patients undergoing reperfusion therapy for stroke. The effect of earlier treatment on disability-free life appears explained by salvage of penumbra, particularly when the ischaemic core is not too large.]]> Thu 17 Feb 2022 09:30:10 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:17430 2 s was the most accurate computed tomography perfusion threshold in predicting the extent of critically hypoperfused tissue with both receiver operating curve analysis (area under curve 0.86), and the volumetric validation (mean difference between computed tomography perfusion and 24-h diffusion-weighted imaging lesions = 2 cm², 95% confidence interval 0.5–3.2 cm²). Cerebral blood flow <40% (of contralateral) within the relative delay time >2 s perfusion lesion was the most accurate computed tomography perfusion threshold at defining infarct core with both receiver operating characteristic analysis (area under curve = 0.85) and the volumetric validation. Using these thresholds, the extent of computed tomography perfusion mismatch tissue (the volume of ‘at-risk’ tissue between the critically hypoperfused and core thresholds) salvaged from infarction correlated with clinical improvement at 24 h (R² = 0.59, P = 0.04) and 90 days (R² = 0.42, P = 0.02). Patients with larger baseline computed tomography perfusion infarct core volume (>25 ml) also had poorer recovery at Day 90 (P = 0.039). Computed tomography perfusion can accurately identify critically hypoperfused tissue that progresses to infarction without early reperfusion, and the computed tomography perfusion cerebral blood flow infarct core closely predicts the final volume of infarcted tissue in patients who do reperfuse. The computed tomography perfusion infarct core and at-risk measures identified are also strong predictors of clinical outcome.]]> Sat 24 Mar 2018 08:01:40 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:19818 Sat 24 Mar 2018 07:56:57 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:27117 Sat 24 Mar 2018 07:41:36 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:22755 1.8 and volume >15 ml, core <70 ml). In a second analysis, we compared outcomes of the perfusion computed tomography-selected rtPA-treated patients to an Australian historical cohort of non-contrast computed tomography-selected rtPA-treated patients. Of 635 patients with acute ischaemic stroke eligible for rtPA by standard criteria, thrombolysis was given to 366 patients, with 269 excluded based on visual real-time perfusion computed tomography assessment. After off-line quantitative perfusion computed tomography classification: 253 treated patients and 83 untreated patients had 'target' mismatch, 56 treated and 31 untreated patients had a large ischaemic core, and 57 treated and 155 untreated patients had no target mismatch. In the primary analysis, only in the target mismatch subgroup did rtPA-treated patients have significantly better outcomes (odds ratio for 3-month, modified Rankin Scale 0-2 = 13.8, P < 0.001). With respect to the perfusion computed tomography selected rtPA-treated patients (n = 366) versus the clinical/non-contrast computed tomography selected rtPA-treated patients (n = 396), the perfusion computed tomography selected group had higher adjusted odds of excellent outcome (modified Rankin Scale 0-1 odds ratio 1.59, P = 0.009) and lower mortality (odds ratio 0.56, P = 0.021). Although based on observational data sets, our analyses provide support for the hypothesis that perfusion computed tomography improves the identification of patients likely to respond to thrombolysis, and also those in whom natural history may be difficult to modify with treatment.]]> Mon 11 Mar 2019 12:14:50 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:41073 Fri 22 Jul 2022 16:57:34 AEST ]]>