1Development of a spreadsheet and a database for

recording, reporting and archiving data from quality

assurance tests of radiological equipment

Samuel Kuttner, Medical Physicist

Department of radiology

UNN, Tromsø, Norway

2012

2HistoryFeb 2009

2 Radiography/CT

Feb 2010

1 Radiography/CT

Sep 2011

1 Radiography/CT

Jan 2012

1 MR1 NM0,5 Radiography/ CT

3

GravdalGravdalGravdalGravdal

KirkenesKirkenesKirkenesKirkenes

LongyearbyenLongyearbyenLongyearbyenLongyearbyen

MosjMosjMosjMosjøenenenen

SandnessjSandnessjSandnessjSandnessjøenenenen

NordreisaNordreisaNordreisaNordreisa

FinnsnesFinnsnesFinnsnesFinnsnes

Number of modalities

Radiography: 67

C-arms 57

CT 15

Workstation monitors~50

Total 189

Northern Norway Regional Health

Authority (Helse Nord RHF)

4Background• Prioritied tasks

• Establish procedures for quality assurance (QA):

• Radiography

• Computed Tomography

• Workstation monitors

• Challenges

• No exsisting procedures – everything had to be ”invented”

• Many modalities (~190 pc)

• 190 constancy controls annually

• 190 reports annually

• Lot of time for report writing!

• Large amount of data to be handled

• We didn’t want this!

5Purpose• Construct a robust system for:

• Recording data from annual QA

• Producing readable reports

• Storing the data in a safe and convinient way

• Excel

• Powerful spreadsheet possibilities

• MySQL

• Free database environment

• May be integrated easily into Excel

MySQL

relational

database

structure

Equipment table

QA session table

QA data table(Partly shown)

Table

Columns

Relations

List of

equipment

Matching by relation

8Automated excel-sheetEnter ID#Query result

Scan parameters

CTDI100 measurements

Scan parameters Measurement dataMySQL query & Trend analysis

10ResultsTolerance

level

Measurement

data Conclusion

11Trend analysis

Baseline values

(MySQL queries)

Measurement

dataDeviations

Conclusion

12Automatically

generated report

How to add data to MySQL?

1. , = .

2. Copy values

3. Paste

4. Ctrl+Shift+Enter

How to query data from MySQL?

• MySQL-editor command line

• One line syntaxes

• Must copy/paste data manually

• Microsoft query (Excel)

• Visual representation of commands

• Returns data to Excel directly

Example queries• Half value layer (HVL)

• Thickness of aluminium required to half the intensity of an x-ray beam

• Plot ALL measured HVL [mmAl], 70kVp, small focal, 2011Measured HVLs in 2011

0

0,5

1

1,5

2

2,5

3

3,5

4

4,5

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58

Modality #

HV

L [

mm

Al]

Top 6 highest HVLs

0

0,5

1

1,5

2

2,5

3

3,5

4

4,5

Varian Acuity Philips BV

Libra

Philips Libra

9

Philips BV

Libra

Philips BV

Libra

Philips BV

Libra

Modality #

HV

L [

mm

Al]

HVL of two identical modalities

0

0,5

1

1,5

2

2,5

3

3,5

4

4,5

Varian Acuity Hospital 1 Varian Acuity Hospital 2

Modality #

HV

L [

mm

Al]

HVL trend analysis• Stationary radiology systems

• Period: 2009-2011

• Increase of HVL over time

HVL trend

2,5

2,6

2,7

2,8

2,9

3

3,1

3,2

3,3

2009 2010 2011

Year

HV

L [

mm

Al]

CT dose in air• 120 kVp, head mode, normalized to mAs, all scanners

• Higher dose for small collimations, due to lower geometric efficiency

Measured CTDI100 air, isocenter, head mode

0

0,2

0,4

0,6

0,8

1

1,2

0 5 10 15 20 25 30 35 40Total collimation, NxT [mm]

CT

DI 1

00/

mA

s [m

Gy

/m

As]

Dual slice 4 slice 16 slice 64 slice

• Dual slice

• Constant dose for all total total collimations.

• Multi slice

• Dose increase with decreasing total collimation

• Due to finite size of the focal spot increases the penumbra.

Larger part of the beam for smaller collimations.

HU of water and air• All kVps, Body mode, all scanners in 2011

Measured HU of water in 2011, Body mode, all 80-140kVp

-8

-6

-4

-2

0

2

4

6

8

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39

Scanner #

CT

DI 1

00/

mA

s [m

Gy/

mA

s]

Measured HU of air in 2011, Body mode, all 80-140kVp

-1060

-1050

-1040

-1030

-1020

-1010

-1000

-990

-980

-970

-960

38 16 9 3 18 11 7 13 34 21 24 27 28 25 23 33 35 37 30 31

Scanner #

CT

DI 1

00/

mA

s [m

Gy/

mA

s]

Water

Air

High voltage measurements

• Measured on radiography and fluoroscopy systems, 2009-2012

• Deviation of measured kVp from nominal values

• 5% tolerance level seems OK!

Deviation of measured kVp from nominal value, 2009-2012

0 %

5 %

10 %

15 %

20 %

25 %

30 %

1 97 193 289 385 481 577 673 769 865 961 1057 1153 1249 1345 1441 1537 1633 1729 1825 1921 2017 2113

Measurement #

Ab

solu

te v

alu

e o

f d

evia

tio

n [

%]

5% of measurements outside 5% tolerance

level

20Ambient light measurements

Same room:

Light on Light offBakgrunnslys

0

20

40

60

80

100

120

140

B2.64

9 (N

evro

gr. 3

)

Ultr

alydg

rans

knin

g (B3.6

88) v

enstr

e

Ultr

alydg

rans

knin

gen

(B3.6

88) h

oyre

Røntg

engr

ansk

ning

stas

jon

3

B2.64

3 (D

emor

om-A

nne-

May

)

Røntg

engr

ansk

ning

stas

jon

2

Røntg

engr

ansk

ning

stas

jon

1

Røntg

engr

ansk

ning

stas

jon

6

Røntg

engr

ansk

ning

stas

jon

4

B3621

(Bar

ngr.

Thore

sten)

Røntg

engr

ansk

ning

stas

jon

5

Røntg

engr

ansk

ning

stas

jon

12

Røntg

engr

ansk

ning

stas

jon

10

Røntg

engr

ansk

ning

stas

jon

11

Røntg

engr

ansk

ning

stas

jon

7

Røntg

engr

ansk

ning

stas

jon

9

Røntg

engr

ansk

ning

stas

jon

8

B3621

(Bar

ngr.

Lill-So

fie)

B2.64

9 (N

evro

gr. T

orgrim

)

Und

ervis

ningsro

m (B

3-61

6)

B3.62

2 (T

horax

gr. S

igne)

B2.64

9 (N

evro

gr. G

ry)

21

Non-diagnostic monitor

Luminance ratio (LR) • LR = Lmaks/Lmin

• LR > 250 (TG-18)

• MDView193 performs better!

MDView 193

22Conclusions

• A comprehensive system for recording, reporting and

archiving data from quality assurance tests of radiological

equipment was developed

• Excel and MySQL are excellent tools for the handling of dose

and image quality data generated from QA tests

• Benchmarking

• Purchasing processes

• Problem solving

• National databases

• Still missing a really user friendly interface

23

Thank you

for your attention!

Reference litterature• IEC, 61223-3-5, Part 3-5: Acceptance tests, 2004

• IEC, 61223-2-6, Part 2-6: Constancy tests, 2006

• ImPACT, Information Leaflet No.1: CT scanner

Acceptance Testing (2001)

• IPEM Report 32. Part III (2003)

• IPEM Report 91 (2005)

• AAPM report 39 (1993)

• AAPM report no.74 (2002)

• AAPM Task group 18 report (2005)

• AAPM Task group 66 report (2003)

• CT manufacturer manuals

• Phantom manuals