DICOM International Conference & SeminarWork Item Implants – Current State and Outlook Michael Gessat email@example.com Thomas Trommer, Armin Löpfe, Oliver Burgert
Outline • Implant Templates and Implantation Planning • Motivation • Features • Information Models • Examples
Implant Templates & Implantation Planning • The pre-operative selection of the most suitable implant and the determination of the optimal position and fixation of an implant in the patient’s body is called implantation planning. • Planning is done with radiological images and graphical representations of implants, called implant templates.
Motivation • At present: • No standardized semantics and syntax for implant templates • No standardized format for planning results • No integration of information flow into PACS HIS PACS Server EHR Data Planning Report Patient Images Planning Workstation Required Templates Implant Templates Vendor Template Repository Intraoperative System Patient Images
Motivation • Our goal: • Implant templates standardized in DICOM • Implantation plans standardizes in DICOM • All data stored in PACS server • Whole data is exchanged via PACS Required Templates HIS Planning Workstation EHR Data Planning Report Planning Report PACS Server incl. Temp. Rep. Patient Images Required Templates Implant Templates Intraoperative System Patient Images
Required Concepts • Patient‘s Morphology • X-Rays, CTs, 3D Ultrasound • Segmentation and Classification • Implant Geometry • 2D • 3D • Result Simulation • Biomechanical properties • Tissue deformation • Transfer into the OR • Network technology & Displays • Transfer protocols and formats
DICOM Sup. 131 and 134 Implants Stents, Valves, … Bone MountedImplants Many more Implant Repository:Bone Mounted Implant Template Storage SOP Class Patient Specific Plan / Report:Implantation Plan Document SOP Class General SurfaceMesh Module EncapsulatedHPGL 2 Based on SR Spine Middle Ear Hip Shoulder Dental
Workshops • In workshops with representatives from the implant industry and implantation planning software industry. • Leipzig, December 13, 2007 • San Francisco, March 3, 2008 • A set of features and attributes was elaborated. • Working Group 24 is working on the translation of the workshop results into DICOM Supplements. • In parallel, ICCAS works on a test implementation of the new DICOM SOP Classes.
Features • Implant Templates • contain 2D and/or 3D representation, • contain (anatomical) landmarks for registration with patient images, • contain information about indication, and • can consist of several components, • Component assembly is described: compatibility, geometric constraints, and degrees of freedom.
1-n 1 Implant produces Manufacturer 1 consists of 1-n spatially defines Frame of Reference 1-n 1 0-n 1-n accepts Component 1 1 1 1 has has has has 0-n 0-n 0-n 0-1 Contact Surface Model 2D Template Fiducial Information Model - Implant Templates
Example Component 1 “Hip Joint Head” “Material: Porcelain” Contact 1 Coordinates Axes Link: Comp. 2, CP 1 Component 2 “Hip Joint Shaft” “Material: Titan” Contact 1 Coordinates Axes Link: Comp. 1, CP 1 Fiducial 1 Femur Axis
Implant Types • Implants for different purposes differ very much in the Attributes and landmarks that describe them. • We propose an encoding mechanism that leaves room for a lot of flexibility. • Only the Attributes that are applicable to the type of implant that is described in one Instance need to be present. General Implant Attributes Hip Joint Assembly Dental Implant
Implantation Plan SR Document: Features Implantation Plan Assembly description Planning Information Registration Templates (Implant Components) Derived Fiducials Anatomical Fiducials Patient Image Visualization Images: ENDOTEC
Image IOD Implantation Plan SR refers to Surface Seg. IOD references Spatial Fiducials IOD spatially aligns Registration IOD Implant IOD contains 2D Templates Fiducials Surface Model Information Model - Implantation Plan SR Document
Thank you very much for your attention! Acknowledgements The Innovation Center Computer Assisted Surgery (ICCAS) at the Faculty of Medicine at the University of Leipzig is funded by the German Federal Ministry for Education and Research (BMBF) and the Saxon Ministry of Science and the Fine Arts (SMWK) in the scope of the initiative “Unternehmen Region” with the grant numbers 03 ZIK 031 and 03 ZIK 032. Gefördert im Rahmen der Technologieförderung mit Mitteln des Europäischen Fonds für regionale Entwicklung (EFRE) und mit Mitteln des Freistaates Sachsen.