Development and anatomical details of Japanese adult male/female voxel models

Transcription

1 Development and anatomical details of Japanese adult male/female voxel models Tomoaki Nagaoka, Soichi Watanabe, *Etsuo kunieda, **Masao Taki and Yukio Yamanaka National Institute of Information and Communications Technology * Department of Radiology School of Medicine, Keio University ** Department of Electrical Engineering, Tokyo Metropolitan University CONTENTS 1. Development and details of voxel models 2. Variable model (recent studies)

2 Objectives Today, modern medical imaging and computer technologies allow development of new realistic (anatomical) whole-body models Develop realistic whole-body models Average Japanese (Asian) body shape Adult male and female Applicable to high-frequency EM fields (over 1 GHz)

3 Procedures for Developing the Voxel Models

4 Step1 : Acquisition of Subject s Whole-body MRI Data (Axial Images) Cast Body Head MRI : Signa Advantage Lx 1.5T Scan parameters Pulse Sequence TR (ms) TE (ms) NSA Thickness (mm) Matrix FOV (mm) Head SE Body SE

5 Original Images for Numerical Models Male 22 Y cm 65 kg Voxel size 2 2 2mm Female 22 Y cm 53 kg Voxel size 2 2 2mm

6 Step4: Identification of Tissue/Organ Types Tissue/organ identification list (extract) ID Tissue/organ R G B ID Tissue/organ R G B 1 2 Skin Muscle Gray matter White matter Example of identification for transverse images Original Image Tissue-identified Image

7 Step5: Final Correction Using 3D Images Smoothing of tissue/organ boundaries Checking the three orthogonal planes(axial,sagittal and coronal) Before Supervision by medical doctors After

8 Details of Present Models

9 3-D Display of Present Models Voxel size: 2x2x2 mm Tissues and organs : 51 different types Mal e Mid-coronal Fema le Ma le Fem ale Mid-sagittal Male Fema le Bone enhancement

10 Body Dimensions (Comparison with average Japanese) Mean deviation of total measurement items Male, 4.03 % ; Female, 3.28 % Height Male H ead length Tibiale height Female H ead breadth 1.00 S ym physion height 0.92 Totalhead height 0.84 Trunk length C hest breadth Bideltoid breadth A bdom inaldepth Bicristalbreadth

11 Masses of tissues/organs (Comparison with average Japanese) Deviation of mass of tissue or organ < 30% Male, about 60% ; Female, :about 80 % Skeleton Muscle Fat Skin Brain Salivary gland Large intestine Heart Kidney Male Female Thyroid Liver Stomach Spleen Pancreas Small intestine

12 Summary of whole-body voxel models of Japanese Realistic high-resolution whole-body voxel models developed using MRI data from a Japanese adult male and female. Highly precise simulation for Japanese (Asian) subjects Electromagnetic exposure evaluation at high frequencies (up to 3 GHz) Applicable to a variety of research fields (Radiation dosimetry, elastic analysis and thermal analysis) Future Plans More suitable for masses of the tissues and organs of an average Japanese Addition of tissues and organs (Yellow and red marrow, etc)

13 Free sharing of database of developed voxel models Web site

14 Recent studies about voxel models Variable model Posture Voxel-dimension Age (figure) Pregnant woman model

15 Development of variable posture model Posture transformation

16 Free Form Deformation Object Control Cell :Control point

17 Posture transformation of developed model using FFD Example of flexion (arm) 0 degrees 45 degrees 90 degrees

18 Example of variable posture model

19 Development of variable voxel-dimension models Example of rescale Size:2 mm Size: 1 mm Smoothing ( The corner part is smooth) Voxel sizel : 2 mm Voxel sizel : 1 mm

20 Development of variable age (figure) models Figure s transformation Child voxel model Adult voxel model

21 Whole-body figures of Children Figure 1 Figure 2 Figure 3 About 3 years old 90cm, 13kg About 5 years old 105cm, 17kg About 7 years old 120cm, 23kg

22 Body-dimension measurements of child Total of measurement items = 66

23 Average figures of child Surface model 3 years old 5 years old 7 years old Figure s transformation (FFD algorithm) Child voxel models

24 Development of pregnant woman model

25 Body-dimension measurements of pregnant woman Subjects ( 5 volunteers) Height: about cm Progestational weight:50-52 kg Age: years old (Japanese woman) After 7 month pregnant Total of measurement items = 104 ( 66 items : same items as child, 37 items: only pregnant woman)

26 Surface model of pregnant woman 10 month

27 MR Image of fetus

28 Future prospects FFD and/or morphing

29 Summary and future plans of variable models and pregnant woman model Introduction of the variable models and pregnant woman model as the results of our present studies The functions of these voxel models are based on adult voxel models We are continuing to improve the models and functions.