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Automatic volume estimation of the thyroid gland using 2D Ultrasound Imaging
presented by
SUBBARAO NIKHIL NARAYAN
School of EEE
Supervisor: Assoc. Prof. Pina Marziliano, School of EEE
Co-Supervisor: Prof. Nadia Magnenat Thalmann, Institute for Media Innovation
Clinical Collaborator: Dr. Christopher Hobbs, Dept. of Otorhinolaryngology, Tan Tock Seng Hospital,
Singapore
11-04-2013
Outline
โข Fundamentals of Thyroid Gland
โขVolume estimation
โขProposed method on 2D US imaging
โข Experimental results
โข Future work
Fundamentals Anatomy Neck Lumps
*Images taken from the internet
- Hormone Regulation
- Iodine Metabolism - Controls energy
usage in body
Functions Pathophysiology
- Hypothyroidism - Hyperthyroidism - Benign Thyroid Disease - Thyroid Cancer
Confirming Diagnosis
- Fine Needle Aspiration Biopsy
Thyroid Imaging
Normal Thyroid Thyroid with disorders
Thyroid Imaging
*Images taken from : www.thyroidimaging.com
Ultrasound
Radiography
Scintiscanning
CT Scan
MRI
Problem Statement
Accurate volume estimation of the thyroid gland using 2D Ultrasound Image / Image Sequences
Objectives:
1. Segmentation of thyroid gland and nodules for volume estimation
2. To develop a mathematical model for accurate estimation of thyroid gland volume.
Importance of Thyroid Volume Estimates
โข Required for differential diagnosis
โข Normal gland volume 5-20ml depending age, gender etc..
โข Required for therapy using radioiodine 131 (131I) [1]
โข Dosage calculation for treatment [1]
๐ท = ๐ โ100
๐ โ ๐ถ
Where, D = 131I dosage (MBq), V = Thyroid volume (ml),
U = 24hr thyroidal 131I uptake(%) and C is a constant
[1]. van Isselt, J.W., et al., Comparison of methods for thyroid volume estimation in patients with Graves' disease. European Journal of Nuclear Medicine and Molecular Imaging, 2003. 30(4): p. 525-531.
Methods to Estimate Thyroid Volume
โข Modality based methods
โข Ellipsoid Method
โข Planimetry Method
โข Cavaliari Method
โข Anthropometric Methods
โข Computer Aided Methods
Ellipsoid Method
โข Thyroid modeled as an ellipse
โข ๐ = ๐
6 โ โ๐๐๐โ๐ก โ ๐ค๐๐๐กโ โ ๐๐๐๐๐กโ [2-4]
โข ๐ = 1.24101 โ ๐
6 โ โ๐๐๐โ๐ก โ ๐ค๐๐๐กโ โ ๐๐๐๐๐กโ + 3.6627[5]
[2]. Kollorz, E.N.K., et al., Quantification of thyroid volume using 3-D ultrasound imaging. Ieee Transactions on Medical Imaging, 2008. 27(4): p. 457-466. [3]. Nygaard, B., et al., Thyroid volume measured by ultrasonography and CT. Acta Radiologica, 2002. 43(3): p. 269-274. [4]. van Isselt, J.W., et al., Comparison of methods for thyroid volume estimation in patients with Graves' disease. European Journal of Nuclear Medicine and Molecular Imaging, 2003. 30(4): p. 525-531. [5]. Ruggieri, M., et al., The estimation of the thyroid volume before surgery - an important prerequisite for minimally invasive thyroidectomy. Langenbecks Archives of Surgery, 2008. 393(5): p. 721-724.
Planimetry Method
โข ๐๐ =๐
6ร ๐ท๐ ร 4
๐ด๐
๐ร๐ท๐ร 4
๐ด๐ก
๐ร๐ท๐ก [6]
where, Dl and Dt are the maximum depth in the longitudinal and transverse sections of the scan, Al and At are crosssectional areas in the longitudinal and
โข Used frequently with 3D imaging modalities like CT/MRI/3D Ultrasound
[6]. V. Brauer, P. Eder, K. Miehle, T. Wiesner, H. Hasenclever, and R. Paschke, Interobserver variation for ultrasound determination of thyroid nodule volumes, Thyroid, vol. 15, no. 10, pp. 1169{1175, 2005.
At
Dt
Cavaliari Method
โข Also known as point counting method [13]:
โข ๐ ๐๐ถ = ๐ ร๐๐ร๐
๐๐ฟ
2ร โ๐
Where ๐๐ and ๐๐ฟ are scaling parameters, ๐ is the number of points hitting the test grid and ๐ is the slice thickness
[13]. U. E. Vurdem, N. Acer, T. Ertekin, A. Savranlar, O. Topuz, and M. Keceli, Comparison of three volumetric techniques for estimating thyroid gland volume, Turkish Journal of Medical Sciences, vol. 42, no. 1, pp. 1299-1306, Dec 2012.
Anthropometric methods
โข Metrics used [14]:
โข ๐๐๐
โข Body Surface Area (๐ต๐๐ด)
โข log (๐) = 0.6089 + 0.832 ร ๐ต๐๐ด + 0.0403 ร ๐๐๐
โข log ๐ = 1.5988 + 0.7965 ร ๐ต๐๐ด โ 0.1755 ร ๐๐๐๐๐๐
where ๐๐๐๐๐๐ = 0 for male and 1 for female
โข All constants obtained by statistical models built using software like IBM SPSS etc.
[14]. C. Veres, J. Garsi, C. Rubino, F. Pouzoulet, F. Bidault, J. Chavaudra, A. Bridier, M. Ricard, I. Ferreira, D. Lefkopoulos et al., Thyroid volume measurement in external beam radiotherapy patients using ct imaging: correlation with clinical and anthropometric characteristics, Physics in medicine and biology, vol. 55, no. 21, p. N507, 2010.
โข [11] and [12] are the only papers that address the issue of Automatic Thyroid Segmentation and Volume estimation.
โข Segmentation Results in [11]: โข Volume estimation done using a new
scheme that makes use of Particle
swarm optimization
โข Drawback: Uses information obtained
from CT scans to determine volume
of US image
โข Volume Segmentation Results in [12]: โข Drawback: Uses biased ellipsoid model
[11] C.Y. Chang, Y. F. Lei, C.H. Tseng, and S.R. Shih, Thyroid Segmentation and Volume Estimation in Ultrasound Images, IEEE Trans. on biomedical engineering, vol. 57, no. 6, June 2010 [12]. Kollorz, E.N.K., et al., Quantification of thyroid volume using 3-D ultrasound imaging. Ieee Transactions on Medical Imaging, 2008. 27(4): p. 457-466.
Computer Aided Methods
Drawbacks of Existing methods
โข All volume estimates are lower than the actual volume
โข Ellipsoid Method is biased [1-4,7]
โข Doctors want new mathematical formulation of volume measurement โ NONE FOUND SO FAR!
โข Volume calculation inaccurate when a nodule(s) is present [1-4,7]
โข Volumes are mostly manually determined and have a high inter-observer variance.
[1]. Nygaard, B., et al., Thyroid volume measured by ultrasonography and CT. Acta Radiologica, 2002. 43(3): p. 269-274. [2]. van Isselt, J.W., et al., Comparison of methods for thyroid volume estimation in patients with Graves' disease. European Journal of Nuclear Medicine and Molecular Imaging, 2003. 30(4): p. 525-531. [3]. Kollorz, E.N.K., et al., Quantification of thyroid volume using 3-D ultrasound imaging. IEEE Transactions on Medical Imaging, 2008. 27(4): p. 457-466. [4]. Ruggieri, M., et al., The estimation of the thyroid volume before surgery - an important prerequisite for minimally invasive thyroidectomy. Langenbecks Archives of Surgery, 2008. 393(5): p. 721-724. [7]. Trimboli, P., et al., A mathematical formula to estimate in vivo thyroid volume from two-dimensional ultrasonography. Thyroid, 2008. 18(8): p. 879-882.
Proposed scheme
โข Use 2D of ultrasound images for volume estimation
Validation
Volume estimation
Thyroid gland segmentation
Preprocessing for artifact removal
Preprocessing for Artifact Removal
โข Manually Induced artifacts in Ultrasound Images:
โข Nodule markings by radiologists
โข Gland description
โข Machine induced markings
โข 150 out of 190 images had artifacts
โข Application of POC based methods [8-10].
[8]. P. Marziliano, M. Vetterli, Irregular sampling in approximation subspaces, SampTA, Loen, Norway, August 1999. [9]. Zhu, X., A.T.S. Ho, and P. Marziliano, Image authentication and restoration using irregular sampling for traffic enforcement applications. ICICIC 2006: First International Conference on Innovative Computing, Information and Control, Vol 3, Proceedings, ed. J.S. Pan, P. Shi, and Y. Zhao2006. 62-65. [10]. Zhu, X., A.T.S. Ho, and P. Marziliano, A new semi-fragile image watermarking with robust tampering restoration using irregular sampling. Signal Processing-Image Communication, 2007. 22(5): p. 515-528.
Artifact Removal - Results
Before artifact removal After artifact removal
N. S. Narayan, P. Marziliano and C. G. L. Hobbs, Automatic Removal of Manually Induced Artefacts in Ultrasound Images of Thyroid Gland, 35th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (IEEE EMBC), July 3-7, 2013.
Qualitative Analysis
โข Restored image PSNR ~ 40dB
โข Algorithm converges within 3 iterations
Convergence of POCS algorithm
Segmentation
โข Novelty:
โข Developed based purely on tissue echogenicity
โข Fully Unsupervised utilizing the state of the art automatic cluster estimation techniques
โข Speckle property of the image treated as a feature instead of noise
N. S. Narayan, P. Marziliano and C. G. L. Hobbs, Echogenicity Based Unsupervised Segmentation of Ultrasound Images of the Thyroid Gland, Submitted to The 16th International Conference on Medical Image Computing and Computer Assisted Intervention (MICCAI), 2013.
Segmentation - Results
N. S. Narayan, P. Marziliano and C. G. L. Hobbs, Echogenicity Based Unsupervised Segmentation of Ultrasound Images of the Thyroid Gland, Submitted to The 16th International Conference on Medical Image Computing and Computer Assisted Intervention (MICCAI), 2013.
Segmentation Accuracy
โข Accurate to a tune of 90%
โข Consistent cluster estimation up to very large thresholds
Stability of algorithm
Future work
โข Pre-process for image based artifacts like Shadow and Enhancement artifacts
โข Upgrade the segmentation algorithm
โข Use of cluster validity schemes
โข Active Contours to aid in segmentation
โข Segment the thyroid gland from the image
โข Developing model for volume estimation
โข Thyroid Volume Calculation
โข Validating the workflow
Questions??
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