ROC Analysis of Three Perfusion Display Options for ECG-gated Perfusion SPECT in Severe CAD

1999 ◽  
Vol 38 (06) ◽  
pp. 172-177
Author(s):  
H. Bailer ◽  
Marianne Gwechenberger ◽  
Martha Pruckmayer ◽  
A. Staudenherz ◽  
G. Kronik ◽  
...  

Summary Aim: The simultaneous computation and display of wall motion and perfusion patterns in a single 3D ventricular model would considerably ease the assessment of ECG-gated Tc-99m-sestamibi SPECT, yet the effect on the accuracy of allocating regional perfusion has so far not been validated. Methods: 3D perfusion mapping (3D Perfusion/Motion Map Software) was compared to the visual assessment of ungated tomographic slices and polar perfusion mapping (Cedars-Sinai PTQ) by correlation analysis and receiver operating characteristics (ROC) analysis at different cut-off levels for coronary stenoses in 50 patients (11 single-, 22 two-, 16 three-vessel disease). Ungated SPECT data were obtained by adding the intervals prior to reconstruction and displaying conventional tomographic slices. All display options were visually assessed in 8 ventricular segments according to a 4-point scoring system and compared to the graded results of coronary angiography. Results: All three display options showed a comparable diagnostic performance for the detection of severe stenoses. The diagnostic gain for the detection of stenoses above 59% was highest for ungated tomographic slices, followed by ungated polar mapping and 3D mapping. Regional assessment revealed a limited performance of 3D mapping in the proximal anterior and distal lateral wall. Polar mapping showed a balanced regional performance. Conclusion: 3D Perfusion mapping provides comparable information to conventional display options with the highest diagnostic strength in severe stenoses. Further improvement of the algorithm is needed in the definition of the valve plane.

Author(s):  
Weiguo Cao ◽  
Marc J. Pomeroy ◽  
Yongfeng Gao ◽  
Matthew A. Barish ◽  
Almas F. Abbasi ◽  
...  

AbstractTexture features have played an essential role in the field of medical imaging for computer-aided diagnosis. The gray-level co-occurrence matrix (GLCM)-based texture descriptor has emerged to become one of the most successful feature sets for these applications. This study aims to increase the potential of these features by introducing multi-scale analysis into the construction of GLCM texture descriptor. In this study, we first introduce a new parameter - stride, to explore the definition of GLCM. Then we propose three multi-scaling GLCM models according to its three parameters, (1) learning model by multiple displacements, (2) learning model by multiple strides (LMS), and (3) learning model by multiple angles. These models increase the texture information by introducing more texture patterns and mitigate direction sparsity and dense sampling problems presented in the traditional Haralick model. To further analyze the three parameters, we test the three models by performing classification on a dataset of 63 large polyp masses obtained from computed tomography colonoscopy consisting of 32 adenocarcinomas and 31 benign adenomas. Finally, the proposed methods are compared to several typical GLCM-texture descriptors and one deep learning model. LMS obtains the highest performance and enhances the prediction power to 0.9450 with standard deviation 0.0285 by area under the curve of receiver operating characteristics score which is a significant improvement.


2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A308-A308
Author(s):  
Lingkang Huang ◽  
Jared Lunceford ◽  
Junshui Ma ◽  
Kenneth Emancipator

BackgroundPD-L1 is expressed on both tumor and immune cells; however, the mechanism by which PD-L1 modulates the adaptive immune response on tumor versus immune cells may differ. Additionally, the prevalence of PD-L1 expression and the partitioning between tumor and immune compartments varies by tumor type. While PD-L1 expression on tumor or immune cells can be scored separately, the PD-L1 combined positive score (CPS) captures both tumor and immune cell expression in one aggregate score. We performed a retrospective, exploratory analysis of the effectiveness of CPS as an enrichment biomarker across several studies of pembrolizumab monotherapy in patients with multiple tumor types.MethodsPD-L1 expression was assessed using PD-L1 IHC 22C3 pharmDx. Expression was measured using CPS (defined as the number of PD-L1–staining cells [tumor cells, lymphocytes, macrophages] divided by the total number of tumor cells, multiplied by 100) in tumor samples from single-arm (KEYNOTE-052 [UC], KEYNOTE-059 cohort 1 [G/GEJ], KEYNOTE-086 [TNBC], KEYNOTE-158 [cervical; SCLC], KEYNOTE-180 [EC], KEYNOTE-224 [HCC], KEYNOTE-427 [RCC]) and randomized (KEYNOTE-040 [HNSCC], KEYNOTE-045 [UC], KEYNOTE-061 [G/GEJ], KEYNOTE-119 [TNBC], KEYNOTE-240 [HCC]) pembrolizumab studies. Data were pooled across tumor types for pembrolizumab and for standard-of-care (in controlled studies), and then estimates of response rate, prevalence, and receiver operating characteristics (ROC) analysis were performed over various CPS cutpoints. CPS distribution by response, tumor type, and line of therapy were also assessed.ResultsThere were 3769 treated patients with available PD-L1 CPS (pembrolizumab, n=2678; standard-of-care, n=1091). The area under the ROC curve for ORR was 0.63 (95% CI, 0.61–0.66) for pembrolizumab and 0.48 (95% CI, 0.43–0.53) for standard-of-care when a positive association was evaluated between CPS and ORR (figure 1); individual cutpoints of 1, 10, 20, and 50 were examined (table 1). Figure 2 shows a boxplot of CPS distribution for response in pembrolizumab-treated patients.Abstract 282 Table 1Response Rates and Sensitivity at Individual CPS Cutpoints for Pembrolizumab-Treated PatientsAbstract 282 Figure 1ROC analysis of PD-L1 CPS for pembrolizumab versus standard-of-care therapyAbstract 282 Figure 2Boxplot of PD-L1 CPS distribution for responders versus nonresponders in pembrolizumab-treated patients by tumor type and line of therapy in order of descending median CPSConclusionsThis retrospective, exploratory pan-tumor analysis demonstrates that CPS is an effective scoring method for measuring PD-L1 expression and can be used as a predictive biomarker to identify patients likely to respond to pembrolizumab monotherapy. CPS demonstrated enrichment of response to pembrolizumab monotherapy across most, but not all, tumor types, including some tumor types for which efficacy favors pembrolizumab regardless of PD-L1 expression, and for which a companion diagnostic is therefore not needed. In the randomized studies, CPS did not show a consistent association with ORR for standard-of-care therapy.


Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Guanglei Xiong ◽  
Iksung Cho ◽  
Heidi Gransar ◽  
Deeksha Kola ◽  
Kimberly Elmore ◽  
...  

Introduction: Coronary CT angiography (CCTA) demonstrates improved performance for diagnosis of high-grade coronary stenoses, but may be affected by artifacts and overestimation of stenosis severity. Whether the addition of resting myocardial perfusion attenuation patterns subtended by stenosis seen on CCTA improves diagnostic performance has not been examined to date. Methods: We evaluated 127 patients (mean age 53.0, 54.3% male) who underwent CCTA and ICA. Percentage of coronary stenosis was assessed by quantitative coronary angiography (QCA), which served as the reference comparator to CCTA. CCTA stenosis was categorized as 0%, 1-24%, 25-49%, 50-69%, 70-99%, and 100% luminal diameter reduction. Automated software (SmartHeart, Redwood City, CA) was used to measure resting CT perfusion attenuation patterns in myocardial segments by AHA 17-segment model. Segmental CT attenuation values were assigned to territories subtended by left anterior descending (LAD), left circumflex (LCX), and right coronary arteries (RCA). Per-patient and per-vessel analyses were based on highest severity (maximal stenosis, minimal attenuation). On both per-patient and per-vessel basis, logistic regression was devised for CCTA stenosis alone and for CCTA plus resting myocardial attenuation. Diagnostic accuracy and area under the receiver operating characteristics curve (AUC) were determined. Results: Diagnostic accuracy of CCTA alone was 84.0%, 85.5%, 90.4%, and 88.6%, at per-patient, per-LAD, per-LCX and per-RCA level, respectively. In comparison, the accuracy of CCTA plus myocardial attenuation were 89.6%, 91.9%, 95.2%, and 92.7%. The AUCs using CCTA alone to discriminate QCA-confirmed coronary stenoses >70% were 0.823 (95% CI: 0.737-0.909), 0.782 (95% CI: 0.667-0.898), 0.690 (95% CI: 0.503-0.878), and 0.793 (95% CI: 0.640-0.945) for per-patient, per-LAD, per-LCX, and per-RCA analysis, respectively. The AUCs using CCTA plus myocardial attenuation improved to 0.864 (95% CI: 0.765-0.962), 0.881 (95% CI: 0.793-0.968), 0.772 (95% CI: 0.535-1.000), and 0.820 (95% CI: 0.685-0.954). Conclusions: The addition of resting CT myocardial perfusion attenuation patterns improves identification and discrimination of high-grade coronary stenosis by CCTA.


2009 ◽  
Vol 48 (04) ◽  
pp. 173-178 ◽  
Author(s):  
H. Ham ◽  
A. Dobbeleir ◽  
P. Santens ◽  
Y. D'Asseler ◽  
I. Goethals

SummaryThe aim of our study was to evaluate the value of a pictorial atlas of 123I FP-CIT SPECT images for aid in the visual diagnosis. Patients, materials, methods: Sixty patients, of whom 20 were clinically diagnosed as ‘non-parkinsonian’ and 40 as having Parkinson's disease or any related disorder, were included in the study. An atlas consisting of 12 123I FP-CIT SPECT images was constructed first. Validity of the atlas was investigated by performing a receiver operating characteristic (ROC) analysis with the clinical diagnosis as the gold standard. The remaining 48 SPECT images were visually assessed twice by 5 observers, first with and secondly without consulting the atlas, or vice versa. The added value of the atlas was investigated by comparing the diagnostic accuracy and the interobserver variability for both methods. Results: ROC analysis performed on the atlas yielded an area under the curve of 1 for a threshold discriminating between clinically non-parkinsonian and parkinsonian patients that was situated between image 4 and 5 of the atlas. For the diagnostic accuracy, we found that the area under the ROC curve was systematically higher if observers had access to the atlas compared to when they had not (Wilcoxon's test, p<0.05). Also, the interobserver variability was significantly lower when observers used the atlas when compared to when they did not (p = 0.05). Conclusion: Diagnostic accuracy was significantly higher and interobserver variability significantly lower if observers had access to the atlas compared to when they had not. Hence, having a pictorial atlas available may facilitate the visual assessment of 123I FP-CIT SPECT scans.


Author(s):  
E DENISENKO-KANKIYA ◽  
F.N. CHANAKHCHIAN ◽  
E.I. VASILENKO ◽  
M.N. VAKHROMEEVA

Известно, что дестабилизация атеросклеротической бляшки коронарных артерий (КА) играет ключевую роль в развитии осложнений хронической ишемической болезни сердца (ИБС). Ранняя диагностика ишемии миокарда и определение субклинического стеноза КА с помощью неинвазивного метода визуализации сердца может стать важным методом в предотвращении развития сердечно-сосудистых осложнений у данной популяции больных. Цель исследования. Определить выраженность преходящих нарушений перфузии миокарда, выявленных при однофотонной эмиссионной компьютерной томографии (ОЭКТ) миокарда у пациентов со стенозами КА различной степени тяжести. Материал и методы. В исследование включен 231 пациент (средний возраст 6210лет). Проанализированы факторы кардиального риска. Всем пациентам проводили ОЭКТ миокарда по стандартному протоколу. Региональную перфузию миокарда оценивали с использованием стандартизированной 20-сегментной модели, на которой оценивали: SSS общий счет снижения перфузии миокарда при нагрузке SDS общую разницу счета, соответствующую степени выраженности преходящей ишемии левого желудочка (ЛЖ). На основании полученных данных обследуемых пациентов классифицировали на группы: с нормальной перфузией (SSS4), незначительной (SSS4-6), умеренной и выраженной степенью снижения (SSS712 и SSS13 соответственно) перфузии миокарда ЛЖ. Результаты SDS классифицировали как: отсутствие ишемии (SDS2), умеренная преходящая ишемия (SDS2-6) и выраженная преходящая ишемия (SDS7). Количественные показатели перфузии миокарда сравнивали с результатами инвазивной коронароангиографии (КАГ). Результаты. Из 231 пациента у 69 (29,9) по данным КАГ были выявлены стенозы до 20, у 126 (54,5) стенозы 2049, у 36 (15,6) стенозы 50 и более. Сравнительный анализ количественных показателей перфузии миокарда (SSS и SDS) и результатов КАГ показал, что достоверные дефекты перфузии после нагрузки и преходящая ишемия ЛЖ определены в основном у пациентов со стенозами КА50 (47,2 и 63,9 соответственно, р0,01). В группе пациентов с стенозами КА 2049 у 42,1 показатели SSS соответствовали незначительной (25,4) и умеренной (16,7) степени снижения перфузии после нагрузки (р0,01). При сопоставлении данных перфузионной сцинтиграфии миокарда выявлена связь между показателем SSS, наличием факторов риска и наличием сопутствующих заболеваний у пациентов с ИБС (р0,05). Заключение. Перфузионная ОЭКТ миокарда может использоваться в качестве метода выявления преходящей ишемии миокарда у пациентов со стенозами КА различной тяжести. Ключевые слова: ишемическая болезнь сердца, однофотонная эмиссионная компьютерная томография, перфузия миокарда, сцинтиграфия миокарда, необструктивное поражение, обструктивное поражение, коронароангиография.Vulnerable atherosclerotic plaque in coronary arteries (CA) is the primary mechanism responsible for complications of CAD even in the terms of non-obstructive CAD. Early determination of myocardial ischemia and CA stenosis with non-invasive imaging technique could predict the development of major cardiac events in patients with CAD. Aim: evaluation the severity of myocardial perfusion defects with single photon emission computed tomography (SPECT) in patients with obstructive or non-obstructive CAD. Material and methods: Overall 231patients (average age of 6210) were analyzed. All patients underwent 1-day gated perfusion SPECT protocol before coronary angiography (CAG). SPECT images were quantified by SSS and SDS using Cedars-Sinai QPS. Normal myocardial perfusion was considered if SSS4 mildly abnormal: SSS4-7 moderate and significantly abnormal: SSS8-12 and SSS13, respectively. Reversible ischemia was defined as SDS2. Degree of ischemia was assessed to moderate (SDS2-7) and severe (SDS7). Obstructive CAD was defined as 50 stenosis in 1 vessel on CAG. Results: From 231 patients 69 (29,9) have non-significant CA stenosis (20), 126 (54,5) have non-obstructive CAD (20-49) and 36 (15,6) - obstructive CAD (50). There were significant differences between CA stenosis severity via CAG and SSS via SPECT. In obstructive CAD significant myocardial perfusion defect at stress (SSS) and reversible ischemia (SDS) were observed in 47,2 and 63,9 patients, respectively (p0,01). In patients with non-obstructive CAD although the majority has normal myocardial perfusion in stress (SSS4 55,6), 42,1 has both mild (25,4) and moderate (16,7) myocardial perfusion defects in stress (p0,001). In this subgroup 45,2 of patients have moderate and 18,3 - severe reversible ischemia according to SDS (p0,001). Abnormal perfusion in stress was associated with hazards of cardiac risk factors or associated diseases (p0,05). Conclusion: Perfusion SPECT has a prognostic value over invasive CAG. The addition SPECT quantitative analysis to CAG allows improved risk stratification of patients with non-obstructive CAD.


1999 ◽  
Vol 6 (3) ◽  
pp. 278-285 ◽  
Author(s):  
E DEPUEY ◽  
S PARMETT ◽  
M GHESANI ◽  
A ROZANSKI ◽  
K NICHOLS ◽  
...  

Circulation ◽  
2015 ◽  
Vol 132 (suppl_3) ◽  
Author(s):  
Anyu Zhou ◽  
Ning Jinag ◽  
Marco Denegri ◽  
An Xie ◽  
Guangbin Shi ◽  
...  

Objectives: To discover the role of altered gene expression regulation in Brugada Syndrome (BrS) and to find biomarkers for BrS diagnosis. Methods: Twenty-five control patients (Control), 25 BrS patients without SCN5A mutation (SCN5A(-)) and 20 BrS patients with SCN5A mutation (SCN5A(+)) were included in this study. Specified gene expression of white blood cells (WBC) were measured by RT-qPCR using TaqMan® Gene Expression assay. Results: MEF2C and MESP1 are the two major cardiac specific transcription factors expressed in WBC. The mRNA expression levels of SCN5A, MEF2C and HuR, one of mRNA stabilizers, were decreased in the SCN5A (+) group (P=0.047, 0.02, 0.000 vs. control group, respectively). The mRNA expression of MESP1 in WBCs was significantly lower in both SCN5A(-) (P=0.012 vs. control) and SCN5A(+) (P=0.000 vs. control) groups. There was no difference between the two BrS groups in MESP1 expression (P=0.215). The area under the Receiver Operating Characteristics (ROC) analysis curve for prediction of BrS using MESP1 levels was 0.775 (95% CI 0.668, 0.882, asymptotic Sig.=0.000). At the optimal cutoff, the corresponding maximum sensitivity and specificity were 0.62 (95% CI: 0.47, 0.76) and 0.88 (0.69, 0.97), respectively. The diagnostic odds ratio (DOR) of MESP1 for BrS diagnosis was 11.96 (95% CI: 5.79, 24.73). The assessment of the mRNA levels in blood SCN5A, MEF2C and HuR were useful for predicting BrS patients with an SCN5A mutation. The area under the ROC analysis curve for prediction of BrS with an SCN5A mutation using SCN5A, MEF2C and HuR mRNA levels in WBCs was 0.847 (95% CI 0.752, 0.942, asymptotic Sig.=0.000), 0.685 (95% CI 0.542, 0.828, asymptotic Sig.=0.016) and 0.777 (95% CI 0.652, 0.902, asymptotic Sig.=0.000), respectively. At the optimal cutoff, the DOR of SCN5A, MEF2C and HuR for SCN5A(+) BrS diagnosis was 17.5 (95% CI: 8.06, 37.86), 4.9 (95% CI: 2.61, 9.17) and 23.5 (95% CI: 9.39, 58.80), respectively. Conclusions: Our results suggest that assessment of circulating MESP1 may be used as a biomarker for BrS diagnosis while decreased SCN5A, MEF2C and HuR mRNA in WBCs is associated with BrS patients with an SCN5A mutation. Our results also suggest that decreased expression of SCN5A, MEF2C, MESP1, and HuR may be pathophysiologically related to BrS.


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