performance comparison of different dr detectors using … · 2017-05-03 · performance comparison...

Performance Comparison of Different DR Detectors Using

Simplified eDQE Approach

Dogan Bor1, Ahmet Guven2, Turan Olgar1, Ozlem Birgul2

1 Ankara University, Faculty of Engineering, Department of Physics Engineering2 Ankara University, Institute of Nuclear Sciences, Department of Medical Physics.

OBJECTİVE

Simplification of eDQE formalism by excluding the beam stop measurements

Comparison of different system performance in terms of eDQE

Use of eDQE for the optimization of clinical image qualities

DETECTIVE QUANTUM EFFICIENCY-DQE

RQABeam quality

Detector

0

0,2

0,4

0,6

0,8

1

0 1 2 3 4

MT

F

freq (mm-1)

1,0E-07

1,0E-06

1,0E-05

1,0E-04

0 1 2 3 4

NN

PS

freq(mm-1)

0

0,2

0,4

0,6

0,8

0 1 2 3 4

DQ

E

freq(mm-1)*IEC-62220-1

W Edge phantom10x10x1 mm

IonChamber

DQE (f) = MTF(f)2

NNPS (f) . K.q

Physical performance of the detector

EFFECTIVE DETECTIVE QUANTUM EFFICIENCY- EDQE-

0

0,2

0,4

0,6

0,8

1

0 1 2 3 4

eMT

F

freq(mm-1)

1,0E-07

1,0E-06

1,0E-05

1,0E-04

0 1 2 3 4

eNN

PS

freq(mm-1)

*Samei et al Med. Phys. 2009

Detector

Grid10:1, 40 lp/mm

0

0,05

0,1

0,15

0,2

0 1 2 3 4eD

QE

freq(mm-1)

IonChamber

eDQE (f) = MTF(f)2 (1 – SF)2

NNPS (f) . TF. K.q

Performance of the system as a whole

INCLUSION OF SCATTER DATA TO THE MTF

Use of Beam Stop Technique

SF =PVAtten.

PVBackg.

0

0,1

0,2

0,3

0,4

0,5

0,6

0,7

0,8

0,9

1

0 0,5 1 1,5 2 2,5 3 3,5 4

MTF

freq(mm-1)

MTF no scatter

MTF x (1-SF)

-0,2

0

0,2

0,4

0,6

0,8

1

-30 -20 -10 0 10 20 30

LSF for different ROI size

50mm

40mm

30mm

20mm

10mm

0

0,2

0,4

0,6

0,8

1

0 0,5 1 1,5 2 2,5 3 3,5

MT

F

freq(mm-1)

10mm(roi)

20mm(roi)

30mm(roi)

40mm(roi)

50mm(roi)

INCLUSION OF SCATTER DATA TO THE MTF

NHSBSP OBJ_IQ (NW. Marshall)

• No truncation and windowing of LSF• Include all the tail of LSF with a large ROI• No normalization of the zero frequenc to unity for MTF

0

0,2

0,4

0,6

0,8

1

0 1 2 3

MT

F

freq(mm-1)

10cm PMMA

0

0,2

0,4

0,6

0,8

1

0 1 2 3

MT

F

freq(mm-1)

25cm PMMA

0

0,2

0,4

0,6

0,8

0 1 2 3

eD

QE

freq(mm-1)

10cm PMMA

0

0,2

0,4

0,6

0,8

0 1 2 3

eD

QE

freq(mm-1)

25cm PMMA

SF = 0.38

SF = 0.44

IncreasingROI size (mm)

1020..

70

COMPARISON OF TWO TECHNIQUE

Systems Kodak DRX-1 Kodak DRX-1C Toshiba FDX4343RPhilips l Pixium

4600

Conversion

phosphorGd2O2S:Tb CsI CsI CsI

Pixel area 35x43cm 43x43cm 43x43cm

Pixel matrix 2544x3056 3072x2560 3008x3072 3001x3001

Pixel pitch 139µm 143µm 143µm

Grid type Stationary Stationary Moving

Grid ratio 10:1 12:1 12:1

Focal spot

size(mm)2.0 1.2 1.2 1.2

TECHNICAL CHARACTERISTICS OF THE FOUR SYSTEM EVALUATED

90 kVp, 25 cm PMMA, AEC control, AK measurements in the Bucky

ACQUISITION GEOMETRIES

IEC Methodology Low scatter, focus unsharpness (G2)

Scatter + focus un harpness (G3)Beam hardening filtering (G1)

SIGNAL TRANSFER PROPERTY-STP

1,0E+02

1,0E+03

1,0E+04

1,0E+05

0,0 5,0 10,0 15,0

Pix

el v

alu

e (L

og

axe

s)

Detector Dose(uGy)

STP-RQA7(IEC geometri)

DRX-1C

DRX-1

Toshiba

Pixium 46001,00E+02

1,00E+03

1,00E+04

1,00E+05

0,00 2,00 4,00 6,00 8,00 10,00

Pix

el v

alu

e (L

og

axe

s)

Detector Dose(uGy)

STP-90kVp_G1

DRX-1C

DRX-1

Toshiba

Pixium 4600

Signal Transfer Properties Functions

Systems RQA Geometry G1 Geometry

DRX-1C y=435.62ln(K)+1166 y=515.71ln(K)+947.45

DRX-1 y=442.29ln(K)+1180.9 y=416.89ln(K)+1071.6

Toshiba FDX4343R y=164.83K+53.535 y=144.87K+56.106

Pixium 4600 y=2509.9ln(K)+14450 y=2560.8ln(K)+14593

MTF RESULTS FOR DIFFERENT DIGITAL RADIOGRAPHY SYSTEMS

0,0

0,2

0,4

0,6

0,8

1,0

0 1 2 3 4 5

MT

F

freq(mm-1)

DRX-1C(4.99µGy)

DRX-1(4.7µGy)

FDX4343R(4.7µGy)

Pixium 4600-II(6.44µGy)

RQA7

G3G1

0,0

0,2

0,4

0,6

0,8

1,0

0 1 2 3 4 5

eMT

F

freq(mm-1)

DRX-1C(4.87µGy)

DRX-1(4.39µGy)

FDX4343R(5.4µGy)

Pixium4600-II(8.16µGy)

0

0,2

0,4

0,6

0,8

1

0 1 2 3 4 5

MT

F

freq(mm-1)

DRX-1C(5.64µGy)

DRX-1(5.17µGy)

FDX4343R(12.79µGy)

Pixium 4600-II(9.44µGy)

NNPS RESULTS FOR DIFFERENT DIGITAL RADIOGRAPHY SYSTEMS

1,0E-07

1,0E-06

1,0E-05

1,0E-04

0 1 2 3 4

NN

PS

freq(mm-1)

DRX-1C(5.64µGy)

DRX-1(5.17µGy)

FDX4343R(5.06µGy)

Pixium 4600-II(4.6µGy)

1,0E-07

1,0E-06

1,0E-05

1,0E-04

0 1 2 3 4

eNN

PS

freq(mm-1)

DRX-1C(4.87µGy)

DRX-1(4.39µGy)

FDX4343R(5.4µGy)

Pixium4600-II(5.09µGy)

RQA

G3G1

1,0E-07

1,0E-06

1,0E-05

1,0E-04

0 1 2 3 4

NN

PS

freq(mm-1)

DRX-1C(4.99µGy)

DRX-1(4.69µGy)

FDX4343R(4.7µGy)

Pixium 4600-II(5.12µGy)

DQE-EDQE RESULTS FOR DIFFERENT DIGITAL RADIOGRAPHY SYSTEMS

0

0,2

0,4

0,6

0,8

0 1 2 3 4

DQ

E

freq(mm-1)

DRX-1C(5.71µGy)

DRX-1(5.17µGy)

FDX4343R(5.06µGy)

Pixium 4600-II(4.66µGy)

0,0

0,2

0,4

0 1 2 3 4

eDQ

E

freq(mm-1)

DRX-1C(4.87µGy)

DRX-1(4.39µGy)

FDX4343R(5.4µGy)

Pixium 4600-II(5.09µGy)

0,0

0,2

0,4

0,6

0,8

0 1 2 3 4

DQ

E

freq(mm-1)

DRX-1C(4.99µGy)

DRX-1(4.69µGy)

FDX4343R(4.7µGy)

Pixium 4600-II(5.12µGy)

RQA

G3G1

COMPARISON OF THREE GEOMETRIES FOR DRX -1C SYSTEM

0

0,2

0,4

0,6

0,8

1

0 1 2 3 4

MT

F

freq (mm-1)

G1-90kVp-(4.99µGy)

G2_LF-90kVp-(4.99µGy)

G2_SF-90kVp-(4.99µGy)

G3_90kVp-(4.87µGy)

0

0,2

0,4

0,6

0,8

1

0 1 2 3 4

eDQ

E

freq(mm-1)

G1_90kVp-(4.99µGy)

G2_LF-90kVp-(4.99µGy)

G2_SF-90kVp-(4.99µGy)

G3_90kVp-(4.87µGy)

Optimization of clinical image quality

CONCLUSION

Could we do some standardization for eDQE ?

Could we simplify the eDQE procedure ?

Optimization of the clinical techniques

Comparison of the clinical performance of different systems

Reliable definition of speed for digital system

Why to measure the eDQE ?

Thank you

bor@eng.ankara.edu.tr