Transcript Productivity Comparison CR vs. DR

Productivity
Comparison
CR vs. DR
The Economic Reason for CR &
DR
CR Defined
CR Equipment
DR Defined
DR Equipment
Introduction
 Workflow: CR-
based
 Workflow: DRbased
Assumptions
 The comparison will look at radiographic
imaging, not the production of crosssectional imaging on film, nor imaging for
interventional radiology
Assumptions
 CR and DR operation
 An
RIS and PACS are in place
 The systems support DICOM MWL and
PPS
 Reading is done on PACS diagnostic
workstations
Fundamental Steps in the Process
 End the examination
 Move the patient out of the examination
room
 Move images to the radiologist to be read
CR-based Workflow (Steps 1-2)
 From the reception
desk or inpatient
schedule,
determine the next
patient to be
examined
 Call for the patient
from the waiting
room or floor
CR-based Workflow (Steps 3-4)
 While the patient is changing or being put
into the room, call up the worklist on the CR
workstation
 Select the appropriate patient and exam
from the worklist
CR-based Workflow (Steps 5-8)
 ID the plate
 Position the patient and the CR plate
 Set the generator and make the exposure
 If there is more than one view, repeat the
above three steps until done
CR-based Workflow (Steps 9-11)
 Carry the CR plates to the plate reader
 Stack the plates in the reader input
 View the images on the CR reader
workstation to be sure of correct position
and exposure
CR-based Workflow (Steps 12-14)
 If the images are not acceptable, return to
re-take the necessary views
 If the images are acceptable, check the
patient ID and request number
 If correct, send the study to PACS
CR-based Workflow (Steps 15-16)
 If not correct, edit
as needed, then
send the study to
PACS
 Return to the exam
room and have the
patient dress or
move to the
holding area
CR-based Workflow
 16 steps
 No film library steps
 The major change is eliminating separate
interaction with the RIS
CR-based Workflow: Variations
 Some systems have the technologist
select the patient and exam at the plate
reader
 Others use the ID and information
recorded on the cassette to associate the
images with the patient and exam
 This changes where a step is done; it does
not add a step
CR Alternatives
 Dedicated chest
and rapid-type
rooms
 Many CR Vendors
are setting up
relationships with
DR vendors to
meet this need
DR-based Workflow (Steps 1-3)
 From the reception desk or
inpatient schedule, determine
the next patient to be
examined
 Call for the patient from the
waiting room or floor
 Have the patient change or
moved into the exam room; log
into the DR system
DR-based Workflow (Steps 4-7)
 Select the patient and examination from the
worklist
 Position the patient
 Set the generator and make the exposure
 If more than one view is needed, repeat the
above two steps
DR-based Workflow (Steps 8-11)
 On the DR system or a QC workstation,
view the images taken
 If not acceptable (photon
starvation/positioning), repeat the needed
views
 If acceptable, end the examination on the
DR system
 Discharge patient
DR-based Workflow
 Reduced to 10 to 11
steps
 No file room tasks
 No interaction with
cassettes
DR-based Workflow
 A single system for capture, QC, and
sending to PACS
 Uses DICOM MWL and PPS to eliminate
technologist interactions with the RIS
 Eliminates carrying cassettes or plates
 Eliminates a separate ID step
Additional Pros for DR Technology
Direct capture means:
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No phosphors
No scintillators
No intermediate steps
No light to diffuse or scatter
Nothing to degrade the quality of the digital signal
Downside of DR
 Replace existing tables/wall Buckys
 May have to replace the generator if the
system cannot be integrated with it
 Not having DICOM MWL and PPS
obviates many of the advantages
 Portable?
Schematic of Workflows
Film-based
Find study to do
Get paperwork
Get patient
Begin exam RIS
Position patient
Expose
Add views?
Flash ID
Log exam in RIS
Locate master
Make exam folder
Put in TBR slot
Load alternator
Log loc in RIS
Carry cassettes
Process films
Reload film
Pick up films
QC films
Films OK?
Films to FL
Discharge Pt
Log into RIS
Complete exam
Log exam
CR-based
DR-based
Find study to do
Find study to do
Get patient
Get patient
Login to DR
Pick from WL
Call up WL
Pick from WL
ID Plate
Position patient
Expose
Position patient
Expose
Add views?
Add views?
Carry plates
Run plates
View images
Images OK?
ID OK?
Images to PACS
Discharge Pt
View images
Images OK?
Edit info
End DR exam
Discharge Pt
Other Workflow Considerations
 Poor planning can defeat the advantages
of CR and DR
 If you design a department for technologist
and patient movement as though you were
using film, you may create problems
Planning Considerations
 For CR, a rate-limiting step may be how far
the plate readers are from the examination
rooms
 Technologist walking time may become
significant
Planning Considerations
 For DR, poor layout may make moving
patients into and out of the rooms a ratelimiting step
 Don’t just consider space when designing
for film replacement; plan around “traffic
flow” as well26
Additional Workflow
 These workflow examples stop at the step
at which the radiologist would interpret the
exam
 There are additional workflow
improvements for PACS over film, but
there is less of an impact from particular
imaging methods
CR vs. DR
 An objective assessment and comparison of
computed radiography (CR) versus digital
radiography (DR) and screen-film for
performing upright chest examinations on
outpatients is presented in terms of:
 Workflow
 Productivity
 Speed
of service
 Potential cost justification
How Was The Study Conducted
 Perceived ease of use and workflow of each device was
collected via a technologist opinion survey.
 Productivity is measured as the rate of patient throughput
from normalized timing studies.
 The overall speed of service is calculated from the time of
examination ordering as stamped in the RIS, to the time of
image availability on the PACS, to the time of interpretation
rendered (from the Transcription System).
 A cost comparison is discussed in terms of potential
productivity gains and device expenditures. Comparative
results of a screen-film (analog) dedicated chest unit
versus a CR reader and a DR dedicated chest unit show a
higher patient throughput for the digital systems.
The Statistics
 A mean of 8.2 patients were moved through the
analog chest room per hour, versus 9.2 patients
per hour using the CR system and 10.7 patients
per hour with the DR system.
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This represents a 12% increase in patient
throughput for CR over screen-film;
a 30% increase in patient throughput for DR
over screen-film, which is statistically
significant; and
a 16% increase in patient throughput for DR
over CR, which is not statistically significant.
Measurements
 Measured time to image availability for interpretation is
much faster for both CR and DR versus screen-film:
 With the mean minutes to image availability
calculated as 29.2 ± 14.3 min for screen-film
6.7 ± 1.5 min for CR
 5.7 ± 2.5 min for DR
 This represents an improved time to image availability of:
 77% for CR over screen-film
 80% for DR over screen-film
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15% for DR over CR
These results are statistically significant (P < .0001) for both CR
over screen-film and DR over screen-film but not statistically
significant for DR over CR.
Conclusion
 A comparison of the digital technology costs
illustrates that the high cost of DR may not be
justifiable unless a facility has a steady high
patient volume to run the device at or near 100%
productivity.
 Both CR and DR can improve workflow and
productivity over analog screen-film in a PACS for
delivery of projection radiography services in an
outpatient environment.
 Cost justification for DR over CR appears to be
tied predominantly to high-patient volume and
continuous rather than sporadic use patterns.
Additional Notes
 There is a potential for workflow
improvement in moving from film to CR and
from CR to DR
 These improvements require integration
with HIS, RIS as well as the
Transcription/Dictations Systems
 Don’t forget department layout effects on
workflow (location, location, location)