Teaching Digital Radiography and Fluoroscopic Radiation Protection

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Flora Banks
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Teaching Digital Radiography and Fluoroscopic Radiation Protection WCEC 20 th Student Educator Radiographer Conference Dennis Bowman, RT(R), CRT (R)(F) Community Hospital of the

for educators and my evaluation afterwards ASRT Best Practices in Digital Radiography Radiographers need to take responsibility for understanding and appropriately performing digital

1 Teaching Digital Radiography and Fluoroscopic Radiation Protection WCEC 20 th Student Educator Radiographer Conference Dennis Bowman, RT(R), CRT (R)(F) Community Hospital of the Monterey Peninsula (CHOMP) - Staff Radiographer Owner/Consultant - Digital Radiography Solutions, FluoroRadPro Speaker - MTMI 2013 WCEC Teaching DR/CR with Best Dose Practices course for educators and my evaluation afterwards ASRT Best Practices in Digital Radiography Radiographers need to take responsibility for understanding and appropriately performing digital radiography procedures because it is their professional duty and an essential component of the radiographers practice standards and code of ethics. We should all be using much higher kv CR 1

DR 50 Kv 60 Kv 70 kv These are the 15-20 kv (higher than film) digital optimum kvs developed by Barry Burns 80 kv 90 kv 100 kv From London, Ontario, a peer reviewed research article published for

Included 91 practitioners (radiologists, radiology residents, radiographers and radiography students).

2 DR 50 Kv 60 Kv 70 kv These are the kv (higher than film) digital optimum kvs developed by Barry Burns 80 kv 90 kv 100 kv From London, Ontario, a peer reviewed research article published for Elsevier s Medical Imaging and Radiation Sciences Examining Practitioners Assessments of Perceived Aesthetic and Diagnostic Quality of High kvp-low mas Pelvis, Chest, Skull, and Hand Phantom Study: Included 91 practitioners (radiologists, radiology residents, radiographers and radiography students). Images: Taken 20 and 30 kv higher (with mas compensation) than the standard preprogrammed technical factors used at the clinical sites. Conclusion: You can go up 20 kvp higher with a compensated lower mas and acquire images of diagnostic quality Of the 4 groups of examiners (radiologists, radiology residents, radiographers and radiography students), who do you believe were the most exacting and hard to please when it came to critiquing the quality of the images? ASRT Best Practices concerning kvp Use the highest kvp within the optimal range for the position and part coupled with the lowest amount of mas as needed to provide an adequate exposure to the image receptor. Here is how much dose you save your patient when you increase the kv and decrease the mas at a 72 SID. Radiation Dose Saved SID kv mas ESE Dose (mr) Radiation Saved (%) 50% EI Decrease (mas) 50% EI Dose (mr) Total Dose Reduction (%) 72" " % % 72" % % 72" % % 72" % % 2

PinnacaleHealth in Harrisburg, PA proves these numbers After giving a presentation for them, their medical physicist wanted to prove my dose savings were accurate.

3 PinnacaleHealth in Harrisburg, PA proves these numbers After giving a presentation for them, their medical physicist wanted to prove my dose savings were accurate. After months of collecting data in specific rooms they used 260 procedures for AP and lateral lumbar spines and extremity s. He discovered that the average dose saved was 30.3% while my chart averages 33.0%. The new standards have 3 important definitions Exposure Index (EI) measure of the radiation in the region of interest (ROI) which may vary depending on manufacturer. Target Exposure Index (EI T ) is the exposure index number when an image is optimally exposed. This will be determined by each facility depending on body part, view, procedure, image receptor and radiologist. Deviation Index (DI) quantifies how much the EI varies from the EI T. How to use the DI numbers or How to Fix an Incorrect mas for repeats Middle column is mas obtained, Top row is DI obtained. The junction of the two is the mas necessary to get a DI of mas Best Practice with Exposure Indicators As a best practice in digital radiography, radiographers must become familiar with the specific EI standards for their equipment, and with the newer standardized EI and DI as they become available in new and upgraded equipment used for digital radiography. 3

I always thought ours was the bad side as the exiting

stand behind the II and usually stands like this, or

Ion chamber is even with patient s hip Readout was 0.

4 I always thought ours was the bad side as the exiting radiation was now larger than the II and would keep coming back towards the tech. We put the ion chamber at 4 because the tech can rarely stand behind the II and usually stands like this, or sometimes even a bit closer. Ion chamber is even with patient s hip Readout was 0.0 ur and it stayed that way everywhere on this side. Ion chamber is now 4 from patient and even with hip on surgeon s side of table. 4

5 Because the surgeon and nurse are always closer than 4 they will get even more exposure. Proving that everyone on the tube side is getting infinitely more radiation than the II side. It s time to give away over $600 in door prizes Instructional DVD Edition 2 Instructional DVD Edition 2 5

6 For instructors to request a free copy Online courses - 4 CEU in Fluoroscopic Radiation Protection and 4 in Digital Radiography Our goal is to show what the exit dose is after 1 min. of exposure and how it will increase with more SID. II touching patient. Dose = mr II 6 above patient. Dose = mr Dose = +7.1% 6

7 II 12 above patient. Dose = mr Dose = +23.2% We wanted to show you what the patient gets as an entrance dose compared to the exit dose. 60 second exposure II 1 off patient. ESE = R II 6 off patient. ESE = R Dose = +33% II 12 off patient. ESE = R Dose = +63% 7

With increased SID, the equipment needs this much more mas because of the Inverse Square Law. How much scatter radiation occurs during an AP chest?

And this one we are calling 0 degrees. Here are all the doses for 0, 45 and 90 degrees (arrows at 6 ) 85@3.

4 90 3 21.1 22.0 21.6 90 4 13.3 12.7 13.0 90 5 10.6 9.0 9.8 90 6 6.9 6.1 6.5 45 1 195.5 196.2 195.9 45 2 79.3 80.7 80.0 45 3 38.3 39.2 38.8 45 4 24.3 23.8 24.1 45 5 16.2 17.9 17.1 45 6 11.6 12.0 11.

0 0.0 0 15 0.0 0.0 0.0 0 16 0.0 0.0 0.0 Dose exposure due to scatter from Portable Chest Xrays Angle of Average Chamber Distance Dose #1 Dose #2 Dose (Deg) (ft) (micror) (micror) (micror) 90 1 316.

3 97.6 98.0 45 5 66.2 65.2 65.7 45 6 48.6 47.4 48.0 45 7 33.6 32.7 33.2 45 8 27.6 27.5 27.6 0 6 76.0 75.1 75.6 0 7 50.5 51.8 51.2 0 8 39.3 39.8 39.6 0 9 32.3 31.9 32.1 0 10 25.4 27.0 26.2 0 11 22.

8 With increased SID, the equipment needs this much more mas because of the Inverse Square Law. How much scatter radiation occurs during an AP chest? We did this experiment many times with and without grids, at 115 and 85 kv, and at 3 different angles. This one is taken at 90 degrees to the patient. This one is taken at 45 degrees to the patient. And this one we are calling 0 degrees. Here are all the doses for 0, 45 and 90 degrees (arrows at 6 ) 85@3.2 and 115@4 Dose exposure due to scatter from Portable Chest Xrays Angle of Average Chamber Distance Dose #1 Dose #2 Dose (Deg) (ft) (micror) (micror) (micror) Dose exposure due to scatter from Portable Chest Xrays Angle of Average Chamber Distance Dose #1 Dose #2 Dose (Deg) (ft) (micror) (micror) (micror) Chest technique of 85@3.2 was used for all exposures. Ionization Chamber angle is measured from mid sagittal plane. Chest technique of 115@4 was used for all exposures. Ionization Chamber angle is measured from mid sagittal plane. 8

9 This demonstration used the arm/hand phantom and a 10x12 CR cassette. We set it up where many techs stand when making a PCXR exposure. This photo and the following image have the cassette at: 45 degrees and 12 feet from the patient. An image cannot lie. Even though the scatter dose is way down in the micro R s, there is enough radiation to make this image with 1 exposure!! This photo and the following image was taken with the phantom/cassette 12 feet from the patient directly behind the tube (which is 6 feet from the patient). This just proves that a few MicroR is still enough radiation to do the job. Ion chamber just above top of phantom, 18 away. 9

10 Ion chamber same height and distance but now at 45 degrees. Ion chamber at 90 degrees with lead apron hanging. Ion chamber still at 90 degrees, but with lead apron removed. Ion chamber at foot end. 10

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patient dose Entrance surface dose, including backscatter was reduced by 39% and effective dose by 41% when the SID was

Also the image quality is increased because the magnification and geometric unsharpness are reduced (because there is

1 New SID 30in (76cm) 36in (91cm) 40in (102cm) 42in (107cm) 44in (112cm) 46in (117cm) 48in (122cm) 50in (127cm) 55in

42in 44in 48in 60in 72in 100in 120in (91cm) (102cm) (107cm) (112cm) (122cm) (152cm) (183cm) (254cm) (305cm) 0.7 0.6 0.5 0.

2 1.1 1.0 0.8 0.5 0.4 0.2 0.1 1.6 1.3 1.2 1.1 0.9 0.6 0.4 0.2 0.2 1.8 1.4 1.3 1.2 1.0 0.6 0.4 0.2 0.2 1.9 1.6 1.4 1.3 1.1 0.7 0.

12 72 (SID) is the new 40! Peer Reviewed article in the Jan/Feb 2015 issue of Radiologic Technology, it was proven that increasing SID will decrease patient dose Entrance surface dose, including backscatter was reduced by 39% and effective dose by 41% when the SID was increased from 100 cm (40 ) to 140 cm (55 ). Also the image quality is increased because the magnification and geometric unsharpness are reduced (because there is less elongation). Exposure-Distance Conversion Chart 40 SID collimated to 16.1 x16.1 New SID 30in (76cm) 36in (91cm) 40in (102cm) 42in (107cm) 44in (112cm) 46in (117cm) 48in (122cm) 50in (127cm) 55in (140cm) 60in (152cm) 72in (183cm) 100in (254cm) 120in (305cm) Exposure- Distance Conversion Chart Original SID 36in 40in 42in 44in 48in 60in 72in 100in 120in (91cm) (102cm) (107cm) (112cm) (122cm) (152cm) (183cm) (254cm) (305cm) SID collimated to 16.1 x16.1 Figuring out attenuation with my body phantom using polyethylene blocks and 500cc saline bags. 12

13 85 14 mas 45 14x17 Entrance 2.13 R 0% Anterior Quarter 1.05 R -50.7% (+49.3%) Middle Midline Dose (MD) R -78% (+22%) Posterior Quarter R -90.8% (+9.2%) Exit R -97.6% (+2.4%) Under Grid (in bucky) R -99.6% (+.4%) 13

A very important legal issue Coming will be a lawsuit for

All radiologists are legally responsible for everything that

To use post collimation, you must show a border of white or

ASRT Best Practices in Digital Radiography Collimation and

to collimate the x-ray beam to the anatomic area appropriate

Electronic masking to improve image viewing conditions should

14 A very important legal issue Coming will be a lawsuit for post collimation (shuttering). All radiologists are legally responsible for everything that is on the original image. To use post collimation, you must show a border of white or pure black to prove you did not crop out any anatomy. Here s a portable humerus on a newborn. The tech could have shuttered like this. ASRT Best Practices in Digital Radiography Collimation and Electronic Masking A best practice in digital radiography is to collimate the x-ray beam to the anatomic area appropriate for the procedure. Electronic masking to improve image viewing conditions should be applied in a manner that demonstrates the actual exposure field edge to document appropriate collimation. Masking must not be applied over anatomy that was contained in the exposure field at the time of image acquisition. 14

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Exposure Indices and Target Values in Radiography: What Are They and How Can You Use Them?

Exposure Indices and Target Values in Radiography: What Are They and How Can You Use Them? Definition and Validation of Exposure Indices Ingrid Reiser, PhD DABR Department of Radiology University of Chicago