Development of Patient Specific 3D Dose Real Evaluation Systems using a Novel Patient based 3

Dimensional Dose Scanner (P3DS) in Tomotherapy*Department of radiation Oncology, College of Medicine, Korea University, Seoul 136-705, Korea,

†INFINITT Healthcare, Seoul 182-4, Korea, $Medical System WILLMED, Seoul 470-8, KoreaSuk Lee*, Jang Bo Shim*, Kyung Hwan Chang*, Yuanjie, Cao*, Jin Kook Kim†,

Jin Soo Ko†, Hong Jung$, Dae Sik Yang*, Young Je Park*, Chul Yong Kim*

3D QA Solution (PDARTS) are …

CONCLUSIONS & DISCUSSIONS

Contact: Suk Lee, Ph.D., e-mail: sukmp@korea.ac.kr, Tel: 82-2-920-5519, FAX: 82-2-927-1419

RESULTS I. In-housed OCT (P3DS)

Schematic Diagram of 3D Patient Specific QA

PDARTS Program for 3D Dose Evaluation : key features In order to offer high-precision advanced radiotherapy to the patients, it is

important to confirm the three dimensional dose distribution and the efficiency of

the patient specific quality assurance which is produced.

Three dimensional dose verification which is using gel dosimeter and optical-CT

can be the best solution but is still lacking in clinical cases.

In this work, we compared planned 3D dose distribution with measured 3D dose

distribution using a non-scattering gel dosimeter and novel in-housed optical CT

scanner in radiotherapy case.

So, we present the preliminary results of the self-developed 3D dose evaluation

solution (patient based dose guided adaptive radiotherapy systems, PDARTS).

Motivation & GOALS

(a) IMRT planning (b) GEL DQA planning

(d) Comparison between plan and gel dose using our PDARTS.

(c) GEL IMRT planning

RTP Data

Gel Data

Block Diagram of 3D Dose Delivery using GEL The results from this study show that there are no significantly discrepancies

between the calculated dose distribution from treatment plan and the measured

dose distribution from a non-scattering gel scanned with a P3DS scanner.

The 3D dose evaluation solution (PDARTS) which is developed in this study

evaluates the accuracy of the three dimensional dose distributions. Further more

comfortable clinical implications could be expected in further study.

It used the tool which it develops from this study, it evaluates the accuracy of the

three dimensional dose distribution and patient specific quality assurance of each

patients with it will be able to confirm the possibility in clinical application.

3D QA Solution (PDARTS) : Clinical application

Case 1.

Diagnosis: Local recurrence of prostate cancer

Stage: T3bN0M0

Treatment aim: Radical

Plan technique: IMRT

Target volume: PTV

Prescribed dose: 200 cGy

Fraction number: 35

Case 2.

Diagnosis: Recurrent nasopharynx cancer

Stage: rcT1N0M0

Treatment aim: Combine

Plan technique: IMRT

Target volume: PTV

Prescribed dose: 180 cGy

Fraction number: 45

CT acquisition of calibration phantom Patient specific quality assurance planning Gel composition

Planning data deliveryData readout & analysis with in-housed scannerEvaluation with PDARTS

Laser alignment marking forthe adjustment between

water phantom and gel object

Alignment setup of gel object Alignment setup of laser CT scanning of DQA phantom

Patient Specific QA Phantom

Scanning

Picture of The New Optical CT Scanner (P3DS)

PDARTS Program for 3D Dose Evaluation : QA View

PDARTS Program for 3D Dose Evaluation : Clinic View

PDARTS by S. Lee

Initial window of PDARTS The view of the isodose between RTP & Gel data

The results of the profile between RTP & Gel data Image processing function of PDARTS

Case 1: Local Recurrence of Prostate

Case 2: Recurrent Nasopharynx

RTP Data

GEL Data

RTP Data

GEL DataIn-housed Scanner

RESULTS II. In-housed 3D Program

Optical Simulation and Preliminary Results

1. Reference Scanning 2. Data Scanning

Projection Dark image Projection Dark image

Water Irradiated gel

VISTATM In-housed Scanner (P3DS)

Scanning Process Projection Image Normalization

3D Reconstruction Results Bolt Experiment for 3D Reconstruction Check

u-offset

v-offset

DSO: distance from source to object

DSD: distance from source to detector Pixel pitch

Water tank Refractive index matching liquid

Gel dosimeter

Camera

Light diffusion sheet

Virtual position of camera

DSD

DSO Pixel size

At front At rear

Geometrical parameters for CBCT Geometry calibration

Refraction I Refraction II

PDARTS by S. Lee

* Acknowledgement: This work was supported by a Korea University Grant.

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