a web interface for 3d visualization and interactive...

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A Web Interface for 3D Visualization and Interactive Segmentation of Medical

Images

H. Jacinto1,3, R. Kéchichian1, M. Desvignes2, R. Prost1, S. Valette1

1 : CREATIS2 : GIPSA-Lab3 : OneFit Medical SAS

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Some of our previous works

1998 : 3D progressive transmission

- html- Netscape plugin (c++)- Cosmo Player

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WebGL

2011 : Google BodyZygote Body

utf8 mesh encoder

→ Pure js is OK

65K limit

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Context

Female Virtual HumanCT scan512*512*1734 = 455 MB

Output :RenderingProcessing (segmentation, detection, ...)

Input :Imaging data : MRI, CT ScannersLarge Volumetric Data

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Medical visualization

MPRWhat physicians want

3D MeshesMedium Bandwidth

Remote Volume Renderinge.g. : ParaviewWebHigh bandwidthHigh server load

Volume RenderingHigh bandwidthHigh client load

MPR

Meshes

Volume Rendering

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MPR

Server-side : Precompute 2D slices

● In-core● about 1:1 RAM → DISK trade● slicing delay (fixable)

Client-side : WebGL (three.js)● <img> → texture● shaders provide:

• Contrast/brightness• HDR• Lookup Tables

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Under the hood

Server-side processing :

● Generic RPC framework● Bare filesystem as storage● RPC Caching

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Data Formats

Voxel Data: DICOM → RAW/ZRAW →Slices

Surfaces : .vtk, .ply, .stl → OpenCTM (just workstm)

utf8, x3d are a possibility,But no web format is the end-goal

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Interactive Segmentation

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Graph cuts

[Boykov & Jolly 2001]

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Graph cuts

Segmentation :Minimal cut

Multiple labels :α-expansion

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Dealing with complexity

[Kéchichian et al. 2011]

Pixels → Clusters → Segmentation

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Voronoi/Delaunay/Lloyd

Initial 2 iterations 50 iterations

E=∑i=1

N

∫V i

ρ(x ).d ( x , pi)2dx

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Anatomical priors

Fat

PatelaCartilage

F

CartilageT

Tibia

Femur

Misc.Outside

Fibula

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Results

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Meshing

Marching Cubes :Too many triangles

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Meshing

Approximated CentroidalVoronoi Diagrams[Valette & Chasserry 04]

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Experiments on tritons/newts

MRI

Segmentation/meshing

- 20 individuals- 2 postures 'I' and 'S'

Collaboration with T. Wardziak (U. Lyon)

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Arthroplasty

Orthopedics :The good angles

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One Fit adapters

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Some results

Reference Ours

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Source code

ClientJs (8 kLOC) + qooxdoo + three.js

Server.php (1 kLOC) OR .js (1 kloc) + node.js

RPC (c++)- slicing/meshing :

github.com/valette/ACVDVTKOpenCTMGDCM

- segmentation : proprietary license

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Thank you