scholarly journals Automatic delineation and quantification of pulmonary vascular obstruction index in patients with pulmonary embolism using Perfusion SPECT-CT: a simulation study

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
David Bourhis ◽  
Laura Wagner ◽  
Julien Rioult ◽  
Philippe Robin ◽  
Romain Le Pennec ◽  
...  
Keyword(s):  
Pulmonary Embolism ◽  
Relative Difference ◽  
Phantom Study ◽  
Complete Analysis ◽  
Difference Threshold ◽  
Z Score ◽  
Lung Volumes ◽  
Phantom Data ◽  
Segmentation Methods ◽  
Perfusion Spect

Abstract Background In patients with pulmonary embolism (PE), there is a growing interest in quantifying the pulmonary vascular obtruction index (PVOI), which may be an independent risk factor for PE recurrence. Perfusion SPECT/CT is a very attractive tool to provide an accurate quantification of the PVOI. However, there is currently no reliable method to automatically delineate and quantify it. The aim of this phantom study was to assess and compare 3 segmentation methods for PVOI quantification with perfusion SPECT/CT imaging. Methods Three hundred ninety-six SPECT/CT scans, with various PE scenarios (n = 44), anterior to posterior perfusion gradients (n = 3), and lung volumes (n = 3) were simulated using Simind software. Three segmentation methods were assesssed: (1) using an intensity threshold expressed as a percentage of the maximal voxel value (MaxTh), (2) using a Z-score threshold (ZTh) after building a Z-score parametric lung map, and (3) using a relative difference threshold (RelDiffTh) after building a relative difference parametric map. Ninety randomly selected simulations were used to define the optimal threshold, and 306 simulations were used for the complete analysis. Spacial correlation between PE volumes from the phantom data and the delineated PE volumes was assessed by computing DICEPE indices. Bland-Altman statistics were used to calculate agreement for PVOI between the phantom data and the segmentation methods. Results Mean DICEPE index was higher with the RelDiffTh method (0.85 ± 0.08), as compared with the MaxTh method (0.78 ± 0.16) and the ZTh method (0.67 ± 0.15). Using the RelDiffTh method, mean DICEPE index remained high (> 0.81) regardless of the perfusion gradient and the lung volumes. Using the RelDiffTh method, mean relative difference in PVOI was − 12%, and the limits of agreement were − 40% to 16%. Values were 3% (− 75% to 81%) for MaxTh method and 0% (− 120% to 120%) for ZTh method. Graphycal analysis of the Bland-Altman graph for the RelDiffTh method showed very close estimation of the PVOI for small and medium PE, and a trend toward an underestimation of large PE. Conclusion In this phantom study, a delineation method based on a relative difference parametric map provided a good estimation of the PVOI, regardless of the extent of PE, the intensity of the anterior to posterior gradient, and the whole lung volumes.

P175 Prognostic value of 99mTc-ECD brain perfusion SPECT in patients with atrial fibrillation and dementia

2020 ◽  
Vol 41 (Supplement_1) ◽  
Author(s):  
H Hashimoto ◽  
R Nakanishi ◽  
S Mizumura ◽  
Y Hashimoto ◽  
Y Okamura ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Atrial Fibrillation ◽  
High Risk ◽  
Prognostic Value ◽  
Cox Model ◽  
Brain Perfusion ◽  
Z Score ◽  
Brain Perfusion Spect ◽  
Perfusion Spect

Abstract Background Atrial fibrillation (AF) is the most common cardiac arrhythmia, and those afflicted have reduced quality of life, functional status, and cardiac performance. The patients with AF have a high risk of coronary heart disease and cardiovascular disease. Although the prevalence of AF is increasing, cognitive disorders are also on the rise in tandem with the aging of the population. The patients with dementia have also experienced lower the quality of life and have increased mortality. Technetium 99m ECD brain perfusion single photon emission computed tomography (99mTc-ECD brain perfusion SPECT) is a useful modality for diagnosing dementia and identifying high risk patients with mild cognitive impairment. However, there are few reports about the relationship between the value of Z score calculated by 99mTc-ECD brain perfusion SPECT and prognosis of patients with AF and dementia. Purpose The aim of this study was to evaluate the prognostic values of brain perfusion using 99mTc-ECD SPECT in patients with AF and dementia. Methods Among 405 consecutive patients who were diagnosed as AF in cardiac outpatients and subsequently diagnosed as dementia using Mini-Mental State Examination by neurologists or psychiatrists, we identified 170 patients (81 ± 10 years) who underwent 99mTc-ECD brain perfusion SPECT for the current study. Of those, 73, 73, and 24 were diagnosed as Alzheimer’s dementia (AD), vascular dementia (VD), and non-specified dementia respectively. Multivariate Cox model was used to assess if higher Z score by 99mTc-ECD brain perfusion SPECT and clinical parameters were associated with major adverse cardiovascular events (MACE) including cardiac death, myocardial infarction, hospitalization for heart failure, and stroke. Sub-analyses of multivariate Cox models by AD or VD were also assessed. The cut-off values of Z score were determined using area under the curve by a receiver operating characteristic analysis based on MACE occurrences. Results During a mean follow-up of 1258 ± 1044 days, 62 MACE occurred. There was not significant difference of MACE between AD and VD (33%, vs. 44%, p = 0.153). By multivariable Cox model, the higher Z score of temporal-occipital-pariental lobe was associated with increased MACE compared to the lower group (HR 2.521, 95% CI 1.465–4.337, p < 0.001). In a sub-analysis of patients with AD, Z score was the most significant prognostic factor for MACE (HR 3.969, 95% CI 1.374–11.468, p = 0.011). The similar trend was observed in those with VD (HR 2.247, 95% CI 1.028–4.913, p = 0.043). Conclusion: This study demonstrated that the Z score of temporal-occipital-pariental lobe by 99mTc-ECD brain perfusion SPECT could be a potential prognostic value among patients with AF and dementia, regardless of type of dementia.

scholarly journals Identifying Influences on Catch-up Growth Using Relative versus Absolute Metrics: Evidence from the MAL-ED Study (P10-014-19)

2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
Stephanie Richard ◽  
Benjamin McCormick ◽  
Laura Murray-Kolb ◽  
Laura Caulfield
Keyword(s):  
Linear Regression ◽  
Relative Difference ◽  
Maternal Height ◽  
Z Score ◽  
Linear Regression Models ◽  
Negatively Associated ◽  
Growth Standards ◽  
Factors Associated ◽  
Catch Up ◽  
Protein Density

Abstract Objectives To identify factors associated with improvement (‘catch-up’) in height and weight from 24–60 mo of age, and to determine whether associated factors differ depending on the metric used (absolute or relative difference from WHO growth standards). Methods At seven MAL-ED sites, 942 children had anthropometry data at 24 and 60 mo, as well as information about socioeconomic status, maternal height, gut permeability (lactulose-mannitol z-score (LMZ)), dietary intake from 9–24 mo, and micronutrient status. Anthropometric changes were categorized in terms of positive changes in Height- or Weight for-Age Z-score (HAZ, WAZ) or their differences (HAD, WAD) and recovery from stunting/underweight, and then modeled using multivariate linear regression. Results 42% of the children were stunted at 24 or 60 mo, and 24% of the children were underweight at 24 or 60 mo. 44% of the children who were stunted at 24 mo were not at 60 mo, and 34% of those underweight at 24 mo were no longer at 60 mo. Among the sites, 49–92% of children had positive changes in their HAZ, whereas 25–60% had positive changes in HAD. Linear regression models indicate that female sex (-0.21 HAZ (95% CI -0.27, -0.15); -0.75 HAD (95% CI -1.07, -0.43)) and mean LMZ (-0.10 HAZ (95% CI -0.16, -0.04); -0.47 HAD (95% CI -0.73, -0.21)) were negatively associated with change in both HAZ and HAD, whereas maternal height was positively associated with change in both HAZ and HAD (0.09 HAZ (95% CI 0.03, 0.15); 0.45 HAD (95% CI 0.15, 0.75)). Similar relationships were identified for change in WAZ and WAD. Dietary protein density was negatively associated with change in WAZ and WAD (-0.05 WAZ (95% CI -0.09, -0.01); -0.11 WAD (95% CI -0.21, -0.01)), and plasma transferrin receptor concentration was positively associated with change in WAZ and WAD (0.02 WAZ (95% CI 0.0, 0.04); 0.04 WAD (95% CI 0.0, 0.08)). Conclusions Children in the MAL-ED study demonstrated recovery from stunting and underweight from 24 to 60 mo of age. Given the similarities in the factors associated with changes in HAZ and HAD (and WAZ and WAD), both be used as complementary approaches to characterize and explain catch-up growth during early childhood. Funding Sources The MAL-ED study was supported by the Bill & Melinda Gates Foundation, with grants to the Foundation for the NIH and NIH/FIC.

An easy Z-score imaging system for discrimination between very early Alzheimer??s disease and controls using brain perfusion SPECT in a multicentre study

2007 ◽  
Vol 28 (3) ◽  
pp. 199-205 ◽  
Author(s):  
Hiroshi Matsuda ◽  
Sunao Mizumura ◽  
Takehiko Nagao ◽  
Tsuneyoshi Ota ◽  
Tomomichi Iizuka ◽  
...  
Keyword(s):  
Multicentre Study ◽  
Imaging System ◽  
Brain Perfusion ◽  
Z Score ◽  
Brain Perfusion Spect ◽  
Perfusion Spect

Comparative analysis of cadmium-zincum-telluride cameras dedicated to myocardial perfusion SPECT: A phantom study

2015 ◽  
Vol 23 (4) ◽  
pp. 885-893 ◽  
Author(s):  
Orazio Zoccarato ◽  
Domenico Lizio ◽  
Annarita Savi ◽  
Luca Indovina ◽  
Camilla Scabbio ◽  
...  
Keyword(s):  
Comparative Analysis ◽  
Myocardial Perfusion ◽  
Myocardial Perfusion Spect ◽  
Phantom Study ◽  
Perfusion Spect

Childhood pneumonia, pleurisy and lung function: a cohort study from the first to sixth decade of life

Thorax ◽  
2019 ◽  
Vol 75 (1) ◽  
pp. 28-37 ◽  
Author(s):  
Jennifer L Perret ◽  
Caroline J Lodge ◽  
Adrian J Lowe ◽  
David P Johns ◽  
Bruce R Thompson ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Lung Function ◽  
Lower Limit ◽  
Transfer Factor ◽  
Study Cohort ◽  
Z Score ◽  
Lung Volumes ◽  
Current Asthma ◽  
Childhood Pneumonia ◽  
Lower Limit Of Normal

IntroductionAdult spirometry following community-acquired childhood pneumonia has variably been reported as showing obstructive or non-obstructive deficits. We analysed associations between doctor-diagnosed childhood pneumonia/pleurisy and more comprehensive lung function in a middle-aged general population cohort born in 1961.MethodsData were from the prospective population-based Tasmanian Longitudinal Health Study cohort. Analysed lung function was from ages 7 years (prebronchodilator spirometry only, n=7097), 45 years (postbronchodilator spirometry, carbon monoxide transfer factor and static lung volumes, n=1220) and 53 years (postbronchodilator spirometry and transfer factor, n=2485). Parent-recalled histories of doctor-diagnosed childhood pneumonia and/or pleurisy were recorded at age 7. Multivariable linear and logistic regression were used.ResultsAt age 7, compared with no episodes, childhood pneumonia/pleurisy-ever was associated with reduced FEV1:FVC for only those with current asthma (beta-coefficient or change in z-score=−0.20 SD, 95% CI −0.38 to –0.02, p=0.028, p interaction=0.036). At age 45, for all participants, childhood pneumonia/pleurisy-ever was associated with a restrictive pattern: OR 3.02 (1.5 to 6.0), p=0.002 for spirometric restriction (FVC less than the lower limit of normal plus FEV1:FVC greater than the lower limit of normal); total lung capacity z-score −0.26 SD (95% CI −0.38 to –0.13), p<0.001; functional residual capacity −0.16 SD (−0.34 to –0.08), p=0.001; and residual volume −0.18 SD (−0.31 to –0.05), p=0.008. Reduced lung volumes were accompanied by increased carbon monoxide transfer coefficient at both time points (z-score +0.29 SD (0.11 to 0.49), p=0.001 and +0.17 SD (0.04 to 0.29), p=0.008, respectively).DiscussionFor this community-based population, doctor-diagnosed childhood pneumonia and/or pleurisy were associated with obstructed lung function at age 7 for children who had current asthma symptoms, but with evidence of ‘smaller lungs’ when in middle age.

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