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Volumetric assessment of body composition from cardiac SPECT CT attenuation maps and association of sarcopenia measures with mortality

Jirong Yi, PhDa Anna M. Michalowska, MD,PhDa,b Aakash Shanbhag, MSca,c Robert J. Miller, MDa,d Jolien Geers, MDa,e Wenhao Zhang, PhDa Aditya Killekar, MSca Nipun Manral, MSca Mark Lemley, BSca Jianhang Zhou, MSca Joanna X. Liang, MPHa Valerie Builoff, BSca Terrence D. Ruddy, MDf Andrew J. Einstein, MD,PhDg Attila Feher, MD,PhDh Edward J. Miller, MD,PhDh Albert J. Sinusas, MD,PhDh Mikolaj Buchwald, PhDa Jacek Kwiecinski, MD,PhDi Paul B. Kavanagh, MSca Damini Dey, PhDa Daniel S. Berman, MDa

Piotr J. Slomka, PhDa

a Cedars-Sinai Medical Center, USA b National Medical Institute of the Ministry of the Interior and Administration, Poland c University of Southern California, USA d University of Calgary, Calgary, Canada e Vrije Universiteit Brussel (VUB), Belgium f University of Ottawa Heart Institute, Canada g Columbia University Irving Medical Center and New York-Presbyterian Hospital, USA h Yale University School of Medicine, United States i Institute of Cardiology, Poland

2024 SNMMI ABSTRACT #2167 [Yi et al., SNMMI 2024]

Slomka Laboratory, CSMC

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Body Composition

  • CT attenuation correction (CTAC)
    • to correct for soft-tissue attenuation
    • contains additional anatomic and pathological information, which is not typically utilized in clinical assessment

  • Body composition analysis
    • reflects the amount and distribution of body tissues, such as skeletal muscles or adipose tissue
    • patients with abnormal body composition measurements are associated with worse outcomes and increased mortality

CTAC

Segmentation

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  • To develop fully automated and annotation-free 6-tissue body composition segmentation algorithm from SPECT CT attenuation maps and evaluate its prognostic significance

Aims

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Cohort creation

  • Computed tomography for attenuation correction (CTAC)
  • Epicardial adipose tissue (EAT)

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Cohort creation

University of Calgary

Columbia University

University of Ottawa

Yale University

Patient number

N=2681

N=1858

N=1417

N=3962

kVp

130

120

120

120

Current

20 mAs

16 mAs

30 mAs

16 mAs

Slice thickness

5 mm

5 mm

3 mm

2.5 mm or 5 mm

4 sites from REFINE SPECT registry

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Methods

CTAC

Deep Learning

Epicardial Adipose Tissue

Subcutaneous Adipose Tissue

Visceral Adipose Tissue

Intramuscular Adipose Tissue

Bone

Skeletal Muscle

Tissue Segmentation

Coronary Artery Calcium

MPI

Analysis

Medical

History

SPECT/CT MPI

  • 10,369 patients
  • 4 sites

Volumetric

Quantification

Prognostic

Evaluation

CTAC – CT attenuation correction,

MPI – myocardial perfusion imaging

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Algorithm design

CTAC

Rib cage segmentation (convex hull)

[1] Wasserthal Radiology: AI 2023

[2] Miller npj Digital Medicine 2024

Intramuscular adipose tissue

Skeletal muscle

Bone

Visceral adipose tissue

Subcutaneous adipose tissue

Epicardial adipose tissue

Integration

CTAC – computed tomography attenuation correction

Pretrainedmodel [2]

Pretrainedmodel [1]

5 body composition tissues segmentation (thresholding)

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Volumetric Quantification

T5

T11

Compute volume index from T5-T11 (appear in 96.4% patient computed tomography attenuation correction scans)

Volume index: volume divided BSA, in cm3/m2

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Analysis

  • Risk stratification thresholds: Youden index-based

  • Kaplan-Meier curves

  • Unadjusted and adjusted Cox regression

Imaging quantification data (3):

stress total perfusion deficit, left ventricular ejection fraction, coronary artery calcium score

History:

Clinical data (8): age, body mass index, gender, family coronary artery disease history, diabetes, dyslipidemia, hypertension, smoking

11 covariates for adjustment

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Segmentation results

CTAC

Segmentation

Non-EAT visceral adipose tissue

Bone

Skeletal muscle

Subcutaneous adipose tissue

Intramuscular adipose tissue

Epicardial adipose tissue

Axial

Coronal

Sagittal

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Results: Volume index

Characteristics

Dead 610

Alive 9308

P-value

Volume index (cm3/m2), median

Bone

329

311

<0.01

Epicardial adipose tissue

55

48

<0.01

Intramuscular adipose tissue

91

87

0.01

Visceral adipose tissue

381

380

0.47

Subcutaneous adipose tissue

977

1,171

<0.01

Skeletal muscle

764

796

<0.01

Non-EAT visceral adipose tissue

Bone

Skeletal muscle

Subcutaneous adipose tissue

Intramuscular adipose tissue

Epicardial adipose tissue

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Cox Regression Hazard Ratio Results

Hazard Ratios [95% CI], p-value

Univariate

Adjusted for 11 factors*

Bone Volume Index

1.3 [1.1, 1.6], <0.01

1.0 [0.9, 1.3], 0.7

EAT Volume Index

1.7 [1.4, 2.0], <0.01

1.7 [1.4, 2.0], <0.01

IMAT Volume Index

1.3 [1.1, 1.6], <0.01

1.5 [1.3, 1.9], <0.01

VAT Volume Index

1.1 [0.9, 1.3], 0.21

1.1 [0.9, 1.3], 0.6

SAT Volume Index

0.6 [0.5, 0.7], <0.01

0.8 [0.7, 1.0], 0.1

SM Volume Index

0.5 [0.4, 0.6], <0.01

0.5 [0.4, 0.7], <0.01

EAT - Epicardial Adipose Tissue, IMAT - Intramuscular Adipose Tissue, SAT - Subcutaneous Adipose Tissue, SM - Skeletal Muscle, VAT - Visceral Adipose Tissue

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Results: Epicardial adipose tissue

Epicardial adipose tissue (EAT)

HR 1.7 [1.4, 2.0], <0.01

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Results: Intramuscular adipose tissue

Intramuscular adipose tissue (IMAT)

HR 1.3 [1.1, 1.6], <0.01

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Results: Skeletal muscle

Skeletal muscle (SM)

HR 0.5 [0.4, 0.6], <0.01

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Results

Intramuscular Adipose Tissue

Skeletal muscle

Bone

Visceral Adipose Tissue

Subcutaneous Adipose Tissue

D E F

A B C

2024 SNMMI ABSTRACT #2167 [Yi et al., SNMMI 2024]

Slomka Laboratory, CSMC

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Results

Intramuscular AT

Skeletal muscle

Bone

Visceral AT

Subcutaneous Adipose

Tissue (AT)

D E F

A B C

2024 SNMMI ABSTRACT #2167 [Yi et al., SNMMI 2024]

Slomka Laboratory, CSMC

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  • Volumetric body composition analysis can be performed automatically from chest CT attenuations scans and is related to all-cause mortality

  • Several volumetric

body composition

measures predict

all-cause mortality

Conclusions

Acknowledgement: Supported in part by Grants R01HL089765 and R35HL161195 from the National Heart, Lung, and Blood Institute/National Institutes of Health (NHLBI/NIH) (PI: Piotr Slomka).

Bone

Epicardial adipose tissue

Intramuscular adipose tissue

Visceral adipose tissue

Subcutaneous adipose tissue

Skeletal muscle

Multivariate analysis