scholarly journals qTICI: Quantitative assessment of brain tissue reperfusion on digital subtraction angiograms of acute ischemic stroke patients

2020 ◽  
pp. 174749302090963
Author(s):  
Haryadi Prasetya ◽  
Lucas A Ramos ◽  
Thabiso Epema ◽  
Kilian M Treurniet ◽  
Bart J Emmer ◽  
...  
Keyword(s):  
Functional Outcome ◽  
Digital Subtraction Angiography ◽  
Quantitative Measure ◽  
Receiver Operating Characteristics ◽  
Binary Logistic Regression Analysis ◽  
Digital Subtraction ◽  
Operating Characteristics ◽  
Vessel Occlusion ◽  
Receiver Operating Characteristics Curve ◽  
Receiver Operating

Background The Thrombolysis in Cerebral Infarction (TICI) scale is an important outcome measure to evaluate the quality of endovascular stroke therapy. The TICI scale is ordinal and observer-dependent, which may result in suboptimal prediction of patient outcome and inconsistent reperfusion grading. Aims We present a semi-automated quantitative reperfusion measure (quantified TICI (qTICI)) using image processing techniques based on the TICI methodology. Methods We included patients with an intracranial proximal large vessel occlusion with complete, good quality runs of anteroposterior and lateral digital subtraction angiography from the MR CLEAN Registry. For each vessel occlusion, we identified the target downstream territory and automatically segmented the reperfused area in the target downstream territory on final digital subtraction angiography. qTICI was defined as the percentage of reperfused area in target downstream territory. The value of qTICI and extended TICI (eTICI) in predicting favorable functional outcome (modified Rankin Scale 0–2) was compared using area under receiver operating characteristics curve and binary logistic regression analysis unadjusted and adjusted for known prognostic factors. Results In total, 408 patients with M1 or internal carotid artery occlusion were included. The median qTICI was 78 (interquartile range 58–88) and 215 patients (53%) had an eTICI of 2C or higher. qTICI was comparable to eTICI in predicting favorable outcome with area under receiver operating characteristics curve of 0.63 vs. 0.62 (P = 0.8) and 0.87 vs. 0.86 (P = 0.87), for the unadjusted and adjusted analysis, respectively. In the adjusted regression analyses, both qTICI and eTICI were independently associated with functional outcome. Conclusion qTICI provides a quantitative measure of reperfusion with similar prognostic value for functional outcome to eTICI score.

scholarly journals Evaluating and comparing biomarkers with respect to the area under the receiver operating characteristics curve in two-phase case–control studies

Biostatistics ◽  
2016 ◽  
Vol 17 (3) ◽  
pp. 499-522 ◽  
Author(s):  
Ying Huang
Keyword(s):  
Case Control ◽  
Receiver Operating Characteristics ◽  
Biased Sampling ◽  
Second Phase ◽  
Operating Characteristics ◽  
Case Control Studies ◽  
Two Phase ◽  
Receiver Operating Characteristics Curve ◽  
The Impact ◽  
Receiver Operating

Abstract Two-phase sampling design, where biomarkers are subsampled from a phase-one cohort sample representative of the target population, has become the gold standard in biomarker evaluation. Many two-phase case–control studies involve biased sampling of cases and/or controls in the second phase. For example, controls are often frequency-matched to cases with respect to other covariates. Ignoring biased sampling of cases and/or controls can lead to biased inference regarding biomarkers' classification accuracy. Considering the problems of estimating and comparing the area under the receiver operating characteristics curve (AUC) for a binary disease outcome, the impact of biased sampling of cases and/or controls on inference and the strategy to efficiently account for the sampling scheme have not been well studied. In this project, we investigate the inverse-probability-weighted method to adjust for biased sampling in estimating and comparing AUC. Asymptotic properties of the estimator and its inference procedure are developed for both Bernoulli sampling and finite-population stratified sampling. In simulation studies, the weighted estimators provide valid inference for estimation and hypothesis testing, while the standard empirical estimators can generate invalid inference. We demonstrate the use of the analytical variance formula for optimizing sampling schemes in biomarker study design and the application of the proposed AUC estimators to examples in HIV vaccine research and prostate cancer research.

Higher Baseline Cortical Score Predicts Good Outcome in Patients With Low Alberta Stroke Program Early Computed Tomography Score Treated with Endovascular Treatment

Neurosurgery ◽  
2020 ◽  
Author(s):  
Peng-fei Xing ◽  
Yong-wei Zhang ◽  
Lei Zhang ◽  
Zi-fu Li ◽  
Hong-jian Shen ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Endovascular Treatment ◽  
Receiver Operating Characteristics ◽  
Operating Characteristics ◽  
Good Outcome ◽  
Poor Outcome ◽  
Poor Outcome Group ◽  
Outcome Group ◽  
Receiver Operating Characteristics Curve ◽  
Receiver Operating

Abstract BACKGROUND Patients with large vessel occlusion and noncontrast computed tomography (CT) Alberta Stroke Program Early CT Score (ASPECTS) <6 may benefit from endovascular treatment (EVT). There is uncertainty about who will benefit from it. OBJECTIVE To explore the predicting factors for good outcome in patients with ASPECTS <6 treated with EVT. METHODS We retrospectively reviewed 60 patients with ASPECTS <6 treated with EVT in our center between March 2018 and June 2019. Patients were divided into 2 groups because of the modified Rankin Score (mRS) at 90 d: good outcome group (mRS 0-2) and poor outcome group (mRS ≥3). Baseline and procedural characteristics were collected for unilateral variate and multivariate regression analyses to explore the influent variates for good outcome. RESULTS Good outcome (mRS 0-2) was achieved in 24 (40%) patients after EVT and mortality was 20% for 90 d. Compared with the poor outcome group, higher baseline cortical ASPECTS (c-ASPECTS), lower intracranial hemorrhage, and malignant brain edema after thrombectomy were noted in the good outcome group (all P < .01). Multivariate logistic regression showed that only baseline c-ASPECTS (≥3) was positive factor for good outcome (odds ratio = 4.29; 95% CI, 1.21-15.20; P = .024). The receiver operating characteristics curve indicated a moderate value of c-ASPECTS for predicting good outcome, with the area under receiver operating characteristics curve 0.70 (95% CI, 0.56-0.83; P = .011). CONCLUSION Higher baseline c-ASPECTS was a predictor for good clinical outcome in patients with ASPECTS <6 treated with EVT, which could be helpful to treatment decision.

Abstract P337: RAPID-LVO for Automated Detection of Intracranial Large Vessel Occlusion in Ct Angiography of the Brain

Stroke ◽  
2021 ◽  
Vol 52 (Suppl_1) ◽  
Author(s):  
Seena Dehkharghani ◽  
Maarten G Lansberg ◽  
Chitra Venkatsubramanian ◽  
carlo W cereda ◽  
Fabricio O Lima ◽  
...  
Keyword(s):  
Ct Angiography ◽  
Sensitivity And Specificity ◽  
Large Vessel ◽  
Receiver Operating Characteristics ◽  
Subspecialty Training ◽  
Emergency Setting ◽  
Large Vessel Occlusion ◽  
Operating Characteristics ◽  
Vessel Occlusion ◽  
Receiver Operating

Background: Identification of large vessel occlusion (LVO) is paramount in the urgent evaluation of acute ischemic stroke (AIS). Emergent interpretation of large and high-complexity data sets, however, may impose strains upon imaging and clinical workflows, motivating development of fast and accurate computer-aided approaches to facilitate LVO detection in the emergency setting. This study investigates the performance of a fully automated LVO detection platform in a mixed cohort of stroke subjects with and without LVO on head and neck CT angiography (CTA). Methods: CTA from two cerebrovascular trials were enriched with cases from eleven global sites. Imaging and clinical variables were balanced between populations including in LVO positivity and across demographic and imaging environments to the extent achievable. Independent and fully blinded review for intracranial ICA or MCA M1 LVO was performed by two subspecialty neuroradiologists. A novel, user-independent imaging analysis application ( RAPID-LVO , iSchemaview inc) was used to predict LVO presence, location, and overall performance relative to reader consensus. Any discordance between readers was adjudicated by a blinded tertiary reader with subspecialty training. Sensitivity, specificity, and receiver-operating characteristics were determined by an independent statistician. Performance thresholds were set a priori, including a lower bound of the 95% CI of sensitivity and specificity of ≥0.8 at mean times-to-notification <3.5 minutes. Results: 217 CTA (median age 65.5, 53% male, 109 LVO(+)) were included. Lower confidence limits of sensitivity and specificity exceeded 90% (sensitivity 0.963, 95% CI 0.909-0.986; specificity 0.981, 95% CI 0.935-0.995), surpassing pre-specified performance benchmarks. Subgroup analyses revealed no decrement in performance relative to subject age or sex, vendor systems, or location of the examination within or outside the United States. The area under the receiver operating characteristics curve was 0.99 (95% CI: 0.971-0.999) and average time-to-notification was 3.18 minutes. Conclusion: RAPID-LVO offers fast, highly accurate, and fully user-independent large vessel occlusion detection across all tested clinical and imaging environments.

Preoperative Magnetic Resonance Volumetry in Predicting Myometrial Invasion, Lymphovascular Space Invasion, and Tumor Grade: Is It Valuable in International Federation of Gynecology and Obstetrics Stage I Endometrial Cancer?

2018 ◽  
Vol 28 (4) ◽  
pp. 666-674 ◽  
Author(s):  
Hilal Sahin ◽  
Fatma Ceren Sarioglu ◽  
Mustafa Bagci ◽  
Tugba Karadeniz ◽  
Hatice Uluer ◽  
...  
Keyword(s):  
Endometrial Cancer ◽  
Tumor Volume ◽  
Myometrial Invasion ◽  
International Federation ◽  
Stage I ◽  
Receiver Operating Characteristics ◽  
Operating Characteristics ◽  
Gynecology And Obstetrics ◽  
Receiver Operating Characteristics Curve ◽  
Receiver Operating

ObjectiveThe aim of this retrospective single-center study was to evaluate the relationship between maximum tumor size, tumor volume, tumor volume ratio (TVR) based on preoperative magnetic resonance (MR) volumetry, and negative histological prognostic parameters (deep myometrial invasion [MI], lymphovascular space invasion, tumor histological grade, and subtype) in International Federation of Gynecology and Obstetrics stage I endometrial cancer.Methods/MaterialsPreoperative pelvic MR imaging studies of 68 women with surgical-pathologic diagnosis of International Federation of Gynecology and Obstetrics stage I endometrial cancer were reviewed for assessment of MR volumetry and qualitative assessment of MI. Volume of the tumor and uterus was measured with manual tracing of each section on sagittal T2-weighted images. Tumor volume ratio was calculated according to the following formula: TVR = (total tumor volume/total uterine volume) × 100. Receiver operating characteristics curve was performed to investigate a threshold for TVR associated with MI. The Mann-Whitney U test, Kruskal-Wallis test, and linear regression analysis were applied to evaluate possible differences between tumor size, tumor volume, TVR, and negative prognostic parameters.ResultsReceiver operating characteristics curve analysis of TVR for prediction of deep MI was statistically significant (P = 0.013). An optimal TVR threshold of 7.3% predicted deep myometrial invasion with 85.7% sensitivity, 46.8% specificity, 41.9% positive predictive value, and 88.0% negative predictive value. Receiver operating characteristics curve analyses of TVR, tumor size, and tumor volume for prediction of tumor histological grade or lymphovascular space invasion were not significant. The concordance between radiologic and pathologic assessment for MI was almost excellent (κ value, 0.799; P < 0.001). Addition of TVR to standard radiologic assessment of deep MI increased the sensitivity from 90.5% to 95.2%.ConclusionsTumor volume ratio, based on preoperative MR volumetry, seems to predict deep MI independently in stage I endometrial cancer with insufficient sensitivity and specificity. Its value in clinical practice for risk stratification models in endometrial cancer has to be studied in larger cohort of patients.

scholarly journals Comparação entre diferentes escores de risco de mortalidade em unidade de tratamento intensivo neonatal

2003 ◽  
Vol 37 (5) ◽  
pp. 591-596 ◽  
Author(s):  
Mariani Schlabendorff Zardo ◽  
Renato S Procianoy
Keyword(s):  
Risk Index ◽  
Receiver Operating Characteristics ◽  
Operating Characteristics ◽  
Porto Alegre ◽  
G 32 ◽  
Clinical Risk ◽  
Receiver Operating Characteristics Curve ◽  
Terapia Intensiva ◽  
Receiver Operating

OBJETIVO: Avaliar peso de nascimento e os escores como preditores de mortalidade neonatal em unidade de terapia intensiva neonatal, comparando os seus resultados. MÉTODOS: Foram avaliados 494 recém-nascidos admitidos em uma unidade de terapia intensiva neonatal (UTIN) de um hospital geral de Porto Alegre, RS, logo após o nascimento, entre março de 1997 e junho de 1998. Foram avaliados o peso de nascimento e os escores considerando a variável óbito durante a internação na UTI. Os critérios de exclusão foram: alta ou óbito da UTIN com menos de 24 horas de internação, recém-nascidos cuja internação não ocorreu logo após o nascimento, protocolo de estudo incompleto e malformações congênitas incompatíveis com a vida. Para avaliação do CRIB (Clinical Risk Index for Babies) foram considerados somente os pacientes com peso de nascimento inferior a 1.500 g. Foram calculadas as curvas ROC (Receiver Operating Characteristics Curve) para SNAP (Score for Neonatal Acute), SNAP-PE (Score for Neonatal Acute Physiology Perinatal Extension), SNAP II, SNAP-PE II, CRIB e peso de nascimento. RESULTADOS: Dos 494 pacientes, 44 faleceram (8,9% de mortalidade). Dos 102 recém-nascidos com peso de até 1.500 g, 32 (31,3%) faleceram. As áreas abaixo da curva ROC variaram de 0,81 a 0,94. Todos os escores avaliados mostraram áreas abaixo da curva ROC sem diferenças estatisticamente significativas. Os escores de risco de mortalidade estudados apresentaram um melhor desempenho que o peso de nascimento, especialmente em recém-nascidos com peso de nascimento igual ou menor que 1.500 g. CONCLUSÕES: Todos os escores de mortalidade neonatal apresentaram melhor desempenho e foram superiores ao peso de nascimento como medidores de risco de óbito hospitalar para recém-nascidos internados em UTIN.

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