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Engineering Research Center for Computer Integrated Surgical Systems and Technology1 600.445 Fall 2006Copyright © R. H. Taylor

Applications of Simulation, Morphometrics and

Robotics in Craniofacial Surgery

C. B. Cutting, F. L. Bookstein

R. H. Taylor

In Computer-Integrated Surgery, R. H. Taylor, S. Lavallee, G. Burdea

and R. Mosges, Eds. Cambridge, Mass.: MIT Press, 1996, pp. 641-662.

Click here for preop/postop pictures

Engineering Research Center for Computer Integrated Surgical Systems and Technology2 600.445 Fall 2006Copyright © R. H. Taylor

GOALS• Computer-assisted planning

of craniofacial osteotomies based on optimal approximation to “normal”(i.e., average) skull shape

• Accurate intraoperative tracking and 6-dof positioning of bone fragments

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Engineering Research Center for Computer Integrated Surgical Systems and Technology3 600.445 Fall 2006Copyright © R. H. Taylor

Engineering Research Center for Computer Integrated Surgical Systems and Technology4 600.445 Fall 2006Copyright © R. H. Taylor

Cut and Move Simulators

C. B. Cutting, F. L. Bookstein and R. H. Taylor, "Applications of Simulation, Morphometrics and Robotics in Craniofacial Surgery," in Computer-Integrated Surgery, R. H. Taylor, S. Lavallee, G. Burdea and R. Mosges, Eds. Cambridge, Mass.: MIT Press, 1996, pp. 641-662.

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Engineering Research Center for Computer Integrated Surgical Systems and Technology5 600.445 Fall 2006Copyright © R. H. Taylor

Cut and Move Simulators

C. B. Cutting, F. L. Bookstein and R. H. Taylor, "Applications of Simulation, Morphometrics and Robotics in Craniofacial Surgery," in Computer-Integrated Surgery, R. H. Taylor, S. Lavallee, G. Burdea and R. Mosges, Eds. Cambridge, Mass.: MIT Press, 1996, pp. 641-662.

Engineering Research Center for Computer Integrated Surgical Systems and Technology6 600.445 Fall 2006Copyright © R. H. Taylor

Cut and Move Simulators

[R. A. Robb and D. P. Hanson, "The ANALYZE software system for visualization and analysis in surgery simulation," in Computer Integrated Surgery, E. S. Lavallee, R. Taylor, G. Burdea and R. Mosges, Eds.: MIT Press, 1996, pp. 175-189.

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Engineering Research Center for Computer Integrated Surgical Systems and Technology7 600.445 Fall 2006Copyright © R. H. Taylor

Physical Simulators: Rapid Prototyping

L. Klimek, H.-M. Klein and R. Mosges, "Simulation of Surgical Procedures in the Craniofacial Region," in Computer-Integrated Surgery, R. H. Taylor, S. Lavallee, G. Burdea and R. Mosges, Eds. Cambridge, Mass.: MIT PRess, 1996, pp. 663-669..

Engineering Research Center for Computer Integrated Surgical Systems and Technology8 600.445 Fall 2006Copyright © R. H. Taylor

Video Simulators

L. Klimek, H.-M. Klein and R. Mosges, "Simulation of Surgical Procedures in the Craniofacial Region," in Computer-Integrated Surgery, R. H. Taylor, S. Lavallee, G. Burdea and R. Mosges, Eds. Cambridge, Mass.: MIT PRess, 1996, pp. 663-669..

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Engineering Research Center for Computer Integrated Surgical Systems and Technology9 600.445 Fall 2006Copyright © R. H. Taylor

The ridge curves of the face

Courtesy: Court Cutting

Engineering Research Center for Computer Integrated Surgical Systems and Technology10 600.445 Fall 2006Copyright © R. H. Taylor

Courtesy: Court Cutting

Dr. Cutting’s map of the face

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Engineering Research Center for Computer Integrated Surgical Systems and Technology11 600.445 Fall 2006Copyright © R. H. Taylor

Computer mesh corresponding to Dr.

Cutting’s map

• Point landmarks• Ridge curves• Additional curves along

geodesic lines between landmarks

• Triangular and quadrangular patches

• Take this data for many patients and average to make atlas

Engineering Research Center for Computer Integrated Surgical Systems and Technology12 600.445 Fall 2006Copyright © R. H. Taylor

Click here for digression on skull averaging

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Engineering Research Center for Computer Integrated Surgical Systems and Technology13 600.445 Fall 2006Copyright © R. H. Taylor

Distance!

Fitting Error for Landmark Points

Engineering Research Center for Computer Integrated Surgical Systems and Technology14 600.445 Fall 2006Copyright © R. H. Taylor

Fitting Error for Ridge Curves

Area!

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Engineering Research Center for Computer Integrated Surgical Systems and Technology15 600.445 Fall 2006Copyright © R. H. Taylor

Fitting Error for Surfaces

Volume!

Engineering Research Center for Computer Integrated Surgical Systems and Technology16 600.445 Fall 2006Copyright © R. H. Taylor

Optimization

Given models bone fragments corresponding to parts of an ideal skull, the computer minimizes a weighted sum of these three distance metrics

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Engineering Research Center for Computer Integrated Surgical Systems and Technology17 600.445 Fall 2006Copyright © R. H. Taylor

Engineering Research Center for Computer Integrated Surgical Systems and Technology18 600.445 Fall 2006Copyright © R. H. Taylor

Automated Osteotomy Ranking

• Computer plans all common osteotomies

• Computer optimizes bone fragment motion and computes error score

• Systematically remove osteotomy lines one at a time in score order. Re-optimize positions and rescore

• Show clinician the plans• Clinician picks desired plan

and further refines based on anatomical/clinical knowledge

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Engineering Research Center for Computer Integrated Surgical Systems and Technology19 600.445 Fall 2006Copyright © R. H. Taylor

Engineering Research Center for Computer Integrated Surgical Systems and Technology20 600.445 Fall 2006Copyright © R. H. Taylor

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Engineering Research Center for Computer Integrated Surgical Systems and Technology21 600.445 Fall 2006Copyright © R. H. Taylor

Engineering Research Center for Computer Integrated Surgical Systems and Technology22 600.445 Fall 2006Copyright © R. H. Taylor

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Engineering Research Center for Computer Integrated Surgical Systems and Technology23 600.445 Fall 2006Copyright © R. H. Taylor

Surgical Execution

Engineering Research Center for Computer Integrated Surgical Systems and Technology24 600.445 Fall 2006Copyright © R. H. Taylor

Tripartite Osteotomies

• Proposed by Converse in 1971 to improve flexibility in shaping the midface.

• Abandoned due to technical difficulty of fragment positioning and fixation

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Engineering Research Center for Computer Integrated Surgical Systems and Technology25 600.445 Fall 2006Copyright © R. H. Taylor

Cutting and Grayson Technique: Inter-occlusal stents

Engineering Research Center for Computer Integrated Surgical Systems and Technology26 600.445 Fall 2006Copyright © R. H. Taylor

First Move

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Engineering Research Center for Computer Integrated Surgical Systems and Technology27 600.445 Fall 2006Copyright © R. H. Taylor

Second Move

Engineering Research Center for Computer Integrated Surgical Systems and Technology28 600.445 Fall 2006Copyright © R. H. Taylor

Third Move

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Engineering Research Center for Computer Integrated Surgical Systems and Technology29 600.445 Fall 2006Copyright © R. H. Taylor

Enter robotics …

• Surgeon did notwant help in making the cuts.

• Surgeon did want help in positioning and holding the bone fragments

• Robots can do this

Engineering Research Center for Computer Integrated Surgical Systems and Technology30 600.445 Fall 2006Copyright © R. H. Taylor

But there were some minor concerns …

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Engineering Research Center for Computer Integrated Surgical Systems and Technology31 600.445 Fall 2006Copyright © R. H. Taylor

Our approach: navigation + passive manipulation aid

Engineering Research Center for Computer Integrated Surgical Systems and Technology32 600.445 Fall 2006Copyright © R. H. Taylor

Optical tracking: NDI Optotrak

Accurate (±0.1 mm) tracking of infrared LED markers over approx 1 m3 workspace

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Engineering Research Center for Computer Integrated Surgical Systems and Technology33 600.445 Fall 2006Copyright © R. H. Taylor

Engineering Research Center for Computer Integrated Surgical Systems and Technology34 600.445 Fall 2006Copyright © R. H. Taylor

Passive Manipulation Aid

• LED markers on adjustable manipulation aid, pointer, and patient skull

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Engineering Research Center for Computer Integrated Surgical Systems and Technology35 600.445 Fall 2006Copyright © R. H. Taylor

Passive Manipulation Aid

• Adjustable surgical clamp holds bone forceps

• Six DOF motion with hand-set brakes

• Remote center-of-motion with iso-center in bone

Engineering Research Center for Computer Integrated Surgical Systems and Technology36 600.445 Fall 2006Copyright © R. H. Taylor

Assembled system

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Engineering Research Center for Computer Integrated Surgical Systems and Technology37 600.445 Fall 2006Copyright © R. H. Taylor

• Computer tracked position of tool optically

• Electric particle brake set when reached target

• Computer played tone to give audible feedback when got close to alignment

Brake

OptotrakRigid Bodies

Possible refinement: computer set brakes with audible feedback cue

Engineering Research Center for Computer Integrated Surgical Systems and Technology38 600.445 Fall 2006Copyright © R. H. Taylor

Possible refinement: computer set brakes with audible feedback cue

Results• Were able to achieve

very good alignments (sub-mm)

• Very tedious to use– Brake was too slow– No “d-tent” effect

Brake

OptotrakRigid Bodies

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Engineering Research Center for Computer Integrated Surgical Systems and Technology39 600.445 Fall 2006Copyright © R. H. Taylor

On to clinical use …• For legal reasons, the

IBM hardware was not used clinically.

• Dr. Cutting was able to re-implement the tracking system using a PIXSYS optical tracker

• First case encountered equipment difficulties and was completed manually

PIXSYS (hung from ceiling)

Engineering Research Center for Computer Integrated Surgical Systems and Technology40 600.445 Fall 2006Copyright © R. H. Taylor

2nd Clinical Case

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Engineering Research Center for Computer Integrated Surgical Systems and Technology41 600.445 Fall 2006Copyright © R. H. Taylor

2nd Clinical Case

• Patient had radiation therapy at relatively early age

• As a result bone around one eye socket failed to grow properly

• Goal was to fix this defect

Engineering Research Center for Computer Integrated Surgical Systems and Technology42 600.445 Fall 2006Copyright © R. H. Taylor

2nd Clinical Case

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Engineering Research Center for Computer Integrated Surgical Systems and Technology43 600.445 Fall 2006Copyright © R. H. Taylor

2nd Clinical Case

Engineering Research Center for Computer Integrated Surgical Systems and Technology44 600.445 Fall 2006Copyright © R. H. Taylor

2nd Clinical Case

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Engineering Research Center for Computer Integrated Surgical Systems and Technology45 600.445 Fall 2006Copyright © R. H. Taylor

2nd Clinical Case

Engineering Research Center for Computer Integrated Surgical Systems and Technology46 600.445 Fall 2006Copyright © R. H. Taylor

2nd Clinical Case

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Engineering Research Center for Computer Integrated Surgical Systems and Technology47 600.445 Fall 2006Copyright © R. H. Taylor

2nd Clinical Case: User Interface

Ergonomics!!!

Engineering Research Center for Computer Integrated Surgical Systems and Technology48 600.445 Fall 2006Copyright © R. H. Taylor

2nd Clinical Case: Display

Rendering

AlignmentIndicators

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Engineering Research Center for Computer Integrated Surgical Systems and Technology49 600.445 Fall 2006Copyright © R. H. Taylor

2nd Clinical Case: Display

• Full 3D display

Engineering Research Center for Computer Integrated Surgical Systems and Technology50 600.445 Fall 2006Copyright © R. H. Taylor

2nd Clinical Case: Display

• Full 3D display• Bone fragments

+ slider bars to show alignment

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Engineering Research Center for Computer Integrated Surgical Systems and Technology51 600.445 Fall 2006Copyright © R. H. Taylor

2nd Clinical Case: Display

• Full 3D display• Bone fragments

+ slider bars to show alignment

• Axes + slider bars to show alignment