PET Project:

current and future developments

A. Trindade – PET/LIP Group

Jornadas LIP, January 2008

Outline:

Development of PET technologies applied to mammography (PET I)

Development of new technologies (PET II)

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Breast cancer is the most common form of cancer among women: 4500 new cases each year in Portugal

Whole body PET using 18F-FDG radiotracer has an increasing application for breast cancer detection

Breast Cancer and PET

infiltrating carcinoma

L. P A

dle

r, Fox C

hase

Cance

r Cente

r

PET: physiological functions of the tissue

There is a need to improve the sensitivity and specificity of PET for small lesions

X-ray: lesion size, shape and tissue density

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Dedicated PET scanners for breast imaging

ClearPEM requirements:

High detection sensitivity

Spatial resolution (1-2 mm FWHM)

Time resolution for backgr. rejection (1-2 ns)

Shorter exams and/or less dose (370 MBq)

Detector concept:

Two planar heads (FOV ~ 15 cm x 17 cm)

Mammary gland and axilla region exams

Exam with the patient in prone position

Ajustable distance between heads and rotation

angle

Breast exam

Axilla exam

Positron Emission Mammography (PEM)

IBEB (Inst. Biofísica e Engª Biomédica - FCUL)

HGO (Hospital Garcia de Orta)

IBILI (Inst. Biomédico Invest. Luz e Imagem - FMUC)

INOV / INESC-ID (Inst. Engª Sistemas Computadores)

INEGI (Inst. Engª Mecânica e Gestão Industrial)

The PET-Mammography Consortium

8 Institutes

40 People

Crystal Clear Collab.

LIP (Lab. Instrumentação e Física Exp. de Partículas)

TagusPark S.A.Financiamento: AdI (Agência de Inovação)

The PET-Mammography consortium was created in December 2002

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Scientific coordination

R&D activities on radiation detectors

Electronic systems arquitecture and development

Data acquisition software development

Detector design and performance studies

Detector integration

Commissioning and pre-clinical tests

PET/LIP Group

R. Bugalho, B. Carriço,

M. Ferreira, R. Moura,

C. Ortigão, J. Pinheiro,

J. C. Silva, P. Rodrigues,

A. Trindade, J. Varela

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Detector Module Performance

Optimization studies:

Crystal surface roughness

Reflector type

Optical coupling medium

Characterization studies:

Energy resolution: 15% @ 511 keV

Ligth collection

DOI resolution: 2.2 mm FWHM

Cross-talk contamination: 4-5%

Ageing effects

Discrete 32 channels electronic setups

Single readout(flood irradiation)

Double readout(flood and colimated

irradiations)

LIP

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APD Quality Control

400 Hamamatsu APD quality control

Gain vs bias voltage

Dark current

Gain gradient

One person full time for 4 months (2006)

Development of an automated setup (2007):

Slots for 16 APDs

Settings - Altera DE2 board/Labview

10 days for 400 APDs

LIP

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ClearPEM at Hospital Garcia de Orta(Installation in 2008, clinical trials with 300 patients)

Control Rack

Robot

INEGI

DetectorHeads

Data Acquisition Electronics

(L1 hardware trigger)

Cooling System(working Temp.=18ºC)

INEGI

Service Rack

1. FE Emulator Electronics (LIP, INOV)2. DAE Server (L2 software trigger) (LIP)3. Service Manager (slow control sw) (LIP)4. High Voltage Supplys5. Low Voltage Supplys

1.

2.

3.

4.

5.

Scanner Operator Workstation

Reconstruction andvisualization software

Acquisition tool (LIP, IBEB, IBILI)

Detector and data info.

First ClearPEM Image (Na-22 source)

Acquired Data

Simulated Data

LIP, IBEB

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Lesion Detectability (5 min. exam)

LIP, IBEB

3D-OSEM images of a breast phantom from simulated dataImages not corrected for attenuation, scatters or randoms

Results support that ClearPEM scanner can improve the detection of breast lesions

5 mm lesions: 100% detectability for all L/B FDG ratios

3 mm lesions: 100% detectability for the highest L/B FDG ratios

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PET I Activities

Detector Integration

First full integration exercice of the ClearPEM system: May 2007 at TagusLIP

All the sub-systems were tested (next talk):

Detector heads integration Front-End electronics Data acquisition electronics Data acquisition and slow control software

Some revisions are currently in progress before the final integration

Commissioning and Pre-clinical tests

Detector calibration methods Image correction techniques: normalization Tests with radioactive phantoms Definition of the scanner operation protocols

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TagusLIP: LIP Laboratory at TagusPark Reorganization of the laboratory in

2007

Inside the bunker Bunker for work withradioactive sources

Laboratory AreaFirst floor

First floor

Computing

Internal network upgraded to Gigabit

Dedicated servers for data analysis and electronics developments

Mass storage in NFS server

Automatic synchronization with PET storage dCache area (FTP Grid)

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PET II Activities

New PET detector modules

Revised APD array / evaluation of Silicon Photomultipliers (SiPMTs)

Revised electronics: frontend and off-detector data acquisition (next talk)

Small animal imaging platform

ClearPEM-Sonic (PET-US)

PET insert for Magnet Resonance Imaging (PET-MRI)

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Baseline design like ClearPEM but several upgrades foreseen

To be installed at TagusLIP:

A technological demonstrator for future PET R&D developments

Link with institutes interested in PET for biomedical applications

Small Animal Imaging Platform

Moby (mouse) phantom Planar geometry

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Small Animal Images

Soft tissuein gray

Bone squeletonin white

Phantom Geometry

Reconstructed Activity

Anatomy/Activity Fusion

3D-OSEM images of a mouse bone scan (18F) from simulated data

Bone uptake

LIP, IBEB