How to minimize

radiation

Nicolaus Reifart

Bad Soden / Wuppertal

10 important steps to lower

radiation exposure in CTO PCI

Deterministic & stochastic effect of

radiation

YOUR PATIENT YOU

04.04.2016

By James Heilman, MD - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=18076961

By Rakesh Ahuja, MD - Own work, CC BY-SA 3.0,

https://commons.wikimedia.org/w/index.php?curid=966501

Important for both of you

Golden Rule:

The ALARA principle

AS LOW AS REASONABLY

ACHIEVABLE

The most important question:

The indication -

Does this patient need to be

cathed?04.04.2016

1

04.04.2016

Shield close to patients body and

close to access -50% scatter

radiation (Fetterly, Magnuson et al. 2011)

2

- 50 %

Good radiation habits

04.04.2016

Detector closer to patient:

Less scatter radiation

Better image quality

(Haqqani, Agarwal et al. 2011 Vascular Annual

Meeting of the Society for Vascular Surgery)

Also: Table height matters.

3

- 20 %

Good radiation habits

04.04.2016

Avoid strong angulationsJournal of Vascular Surgery 2012 55, 799-805

Worst angulations: LAO lateral, caudal and

cranial. Use PA angulations if possible

(Kuon , JACC 2004)

Avoid “ dark” obstacles: Bones, metal

belly and liver (deep breath)

4

- 80 %

Good radiation habits

3.3 mGy/s 2.9 mGy/s

4

Dont forget to collimate

- 12 %

+

Shade the „sunny“ part

• Reduces

radiation

• Improves

picture-quality

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7

- 10 %

+

Good radiation habits

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Step back while

filming5

- 80 %

Tube: 1m

Cost: 0.5€

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- 75 %

The fantastic little tube saves you…

Fluoroscopy Cine

Fluoro instead of Cine

0.1 mGy/sec 1.0 mGy/sec

- 90 %

6

Fluoro

Store/Last

Image Hold for

documentation

Know your machine

Film runs as short as

possible

• 2 heartbeats are sufficient to

visualize lesions

–If you need to visualize late

filling: start with fluoro with

cine to follow

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7

- 40 %

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When performing dual injection to

visualize collaterals:

Start with fluoro till the distal

vessel is filled via collaterals,then

inject antegrade and start cine - 50 %

Film runs as short as possible

Frame rate 7.5/s = 1 mGy/sFrame rate 15/s =2.2 mGy/s

8

Reduced frame rate!

- 55 %

Avoid magnification!

Increases radiation for the

patient 2 to 4 fold

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9

- 60%

x 1.6 - 4

Reduction in CTO98 vs 98 patients; single operator 7.5 F/s

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10 p < 0.000002

J. Reifart, DGK Mannheim 2016

- 30 %

-30% off total dose

regardless of user

CTOs on your best

machine

• best

resolution

• lowest

exposure

• biplane not

mandatory04.04.2016

CTO Lab

The 10 + Take home

messages:

1. Proper indication

2. Use all kinds of shielding (transparent,

leaden curtain, legs and abdomen)

3. Adjust detector & table

4. Collimation

5. Avoid magnification

6. Avoid bones, metal and liver (deep breath)

The 10 + Take home

messages:

7. Avoid LAO lateral/caudal/ cranial if

possible

8. Keep Cine runs short, Fluoro instead of

Cine

9. 7.5 frames/sec not 15 or 30

10. Step back while filming (tube!)

11.Use optimal equipment

€-CTO: Dye Consumption (ml)

2008 2009 2010 2011 2012 2013

Retrograde: 359 ml

My basic rules to save dye

• Dye – alert at GFR x 4

• Upper limit of dye: GFR x 6

• Dye dilution 1:1 at 15 frames / min in

patients with GFR<30

• Never inject twice: Store every fluoro-shot

• Superselective injection if possible

Checking

collaterals:

10 ml of

dye

Super-

selective:

2 ml of dye

Severe renal

dysfunction

GFR 28

Dye: NaCl

1:1

Set at high

resolution

5 runs

Total

volume of

Dye:

18 ml

Save dye =

save the

kidney

Thankyou

for

considering

Thank you

04.04.2016

Methods

04.04.2016

We used the doseaware

system to compare

different radiation safety

techniques.

Know what you want

to see

5

8 Frames without

information

+

Know what you want to see

Time radiation with contrast

application

• start radiation when contrast dye is

already in guide

5

- 20 %

+

Fluoroscopy / Procedure (min)

Ante - versus Retrograde 2011-13

+120%

+ 77%

+37%

Success Antegrade vs Retrograde

75

Success Retrograde related to

„accceptance“

%

Success Retro related to

experience

%

Operators* related Fluoro time

and exposure (cGy) 2012/13

* > 50 cases registrated>7 Gy

< 0.9 Gy

Operators* related Fluoro time

2012/13

* > 50 cases registrated

min

cGy per minute Fluoro-Time

Operators with > 50 pts 2012/13

Diff. up to 250%