Cover Sheet (turn in with assignment)cis/cista/445/Homework_2002/Homework-4/hw4.pdf · Cover Sheet (turn in with assignment) • Name: _____ • Email or other contact ... This problem

Engineering Research Center for Computer Integrated Surgical Systems and Technology1 600.445 Fall 2000; Updated: 28 November 2001

Copyright © R. H. Taylor

Cover Sheet (turn in with assignment)

• Name: _________________________________• Email or other contact: _____________________• I have followed the rules for this graded assignment

______________________Signature

201

202

PointsPoints PossibleProblem

100Total

304

303



600.445 Homework #4 – Fall 2001

• Remember that this is a graded homework assignment.• You are to work alone and are not to discuss the problem

with anyone other than the TAs or the instructor.• It is otherwise open book, notes, and anything else except

previous years’ homework problems and exams.• You may not refer to previous years’ homework & exams• Please refer to the course organizational notes for a fuller

listing of all the rules. I am not reciting them all here, but they are still in effect.

• Be neat and show enough work so TAs can grade this• Unless I say otherwise in class or the TA grant an

extension, this assignment is due before the start of class on October 26, 2000.



Problem BackgroundThis problem concerns CIS approaches to the problem of prostate brachytherapy. The next few slides, which were graciously provided by Dr. Gabor Fichtinger, give useful background on this procedure.



Why Prostate?

We can make a huge differenceWe can make a huge difference– 200,000 new prostate cancer per year– 1,000,000 biopsies per year– BPH: 11,000,000 current cases– 25% of males has prostate condition

• PC, BPH, Prostatitis (chronic testicular and pelvic pain)

• Seems to be doable• Drives core research• Pre-existing experience• Strong clinical support • Industrial participation



Prostate diseases and treatments• Adenocarcinoma

– Prostatectomy - resection

– External beam – high energy X-ray

– Bracytherapy – implanted radioactive sources

– Experimental local therapies• Thermal (RF, Magnetic, HiFu, US, cryosurgery)• Gene therapy

• BPH– TURP– Thermal (RF, HiFu)

• Biopsy– Sextant + targeted



Standard Approach Today

•TRUS•Template•Manual insertion

(Burdette’s Interplant®)



Transrectal US guided brachytherapy



Transrectal Ultrasound Probe,Template, and Stepper



Intraoperative Patient Position and Setup



Transrectal Ultrasound of the Prostate



Prostate Implant Preplanning

Obtain axial ultrasound images of the prostate from apex to base in 5 mm increments

Base 0 mm 5 mm 10 mm 15 mm

20 mm 25 mm 30 mm Apex 35 mm



Defining Regions of Interest



Isodoses and Selection of Seed Loading



The Brachytherapy Pre-Plan



Before insertion

(Burdette’s interplant®)



Urethral Sparing



Prescription Dose Coverage



3D Volume Visualization: Seeds



3D Volume Visualization: Seeds



Dose Volume Histograms (DVH)

Urethral (100%)

Prostate (94%)

Rectal (38%)



Traditional vs. Intraoperative Brachytherapy



Result: Implanted prostate



Transverse CT Slice with Dose



Orthogonal CT Views with Dose Overlay



Mess after insertion



The problem

Summary: You are to sketch and compare the designs of two clearly distinct approaches to improving the procedure of prostate brachytherapy. You will then be asked to provide additional information concerning your preferred approach. Some specific questions will be later.– You may employ any intraoperative or preoperative

imaging devices you desire, with whatever preparation (e.g., fiducial implantation) is appropriate. You should consider costs and other trade-offs however.

– You should recall that the prostate itself is not visible in fluoroscopy and does not show up well in CT. MRI gives superb tissue discrimination. Ultrasound will usually enable the surgeon to identify the prostate capsule but not to see the tumors.



Questions 1 and 2 (20 points each)1, 2 (20 points each ): Outline the design of two distinctsystems for computer-assisted prostate brachytherapy. Your designs should include a rough sketch and a data flow block diagram along the lines of the Surgical CAD/CAM diagrams introduced in class. You should include at least the following information:

– Images used for different phases of the procedure– Identification of key analysis components, algorithms and

interface devices, explaining key inputs and outputs– Outline of procedure and how the components are used.

The two systems need to be significantly different in at least one key respect (imaging, method of providing assistance, etc.). I am not looking for a book, 1-2 pages max plus sketches per system at this point. You should make reference to the systems, technology, and other material covered in class.



Question 3 (30 points)

3 (30 points) Analyze and compare your proposed systems from the following perspectives:

– What are likely to be the key technical problems in implementation?

– What are the cost/performance trade-offs?– What are the other advantages and disadvantages

from the surgeon’s perspective? From the hospital’s? From the patient’s?

– How long will each take to implement? To validate?

Based on this discussion, select a preferred embodiment and justify your choice.



Question 4 (30 points)

3 (30 points) Now flesh out the design of your preferred embodiment. This discussion should include:

– Provide additional detail about any special apparatus you propose to create, to sufficient detail so that your answers to the other questions is clear

– Outline the key coordinate transformations and other geometric relationships in your approach

– Outline the key factors affecting accuracy & show in formulas how they relate to the transformations

– Outline how you would approach solving the key problems you identified in question 2.

Documents

Cover Sheet (turn in with assignment)cis/cista/445/Homework_2002/Homework-4/hw4.pdf · Cover Sheet (turn in with assignment) • Name: _____ • Email or other contact ... This problem