Diabetic Retinopathy-screening training course for nurses St John Eye Hospital and UNRWA nurses

1. UNIT 1:
DIABETIC RETINOPATHY SCREENING
PROGRAMS, PRINCIPLES AND
PROCESSES
Dr. Riyad Banayot
St. John of Jerusalem Eye Hospital
Diabetic Retinopathy Screening

2. Diabetic Retinopathy Screening
Programs, Principles and Processes
A. The purpose of screening
B. The impact that screening may have on the patient
C. The procedures in a Screening Program
D. Quality assurance in the Screening Program
E. Understand the factors which lead to effective
screening
F. Impact of screening on Ophthalmology services
G. Guidelines to help identify patients currently
attending hospital ophthalmology clinics who are
suitable for transfer to the screening program

3. The purpose of screening
a. What does screening mean?
b. The prime purpose of screening for DR.
c. Why is it important to screen for diabetic
retinopathy?
d. Limitations of the screening test and
process.

4. What does screening mean?
 A screening test should be:
 Simple to apply
 Easy to perform
 Can identify those with disease and exclude those
without.
 The validity of screening lies in its ability to
correctly categorize cases with:
 “Sight threatening DR” (usually symptomatic) or
 Those without symptoms (includes “No DR” and
“Non Proliferative Diabetic Retinopathy”).

5. What does screening mean?
 A screening test should be:
 Simple to apply
 Easy to perform
 Can identify those with disease and exclude those
without.
 The validity (strength) of screening lies in its
ability to correctly categorize cases with:
 “Sight threatening DR” (usually symptomatic) or
 Those without symptoms (includes “No DR” and
“Non Proliferative Diabetic Retinopathy”).

6. For screening to be effective;
Screening should:
 Be suitable, reliable, sensitive and specific
 Offer effective treatment
 Offer high level of acceptance among target
population
 Comply with treatment and minimal costs so
as not to outweigh its benefits
 Be a continuous process, not a one-off

7. For screening to be effective;
Screening should:
 Be suitable, reliable, sensitive and specific
 Offer effective treatment
 Offer high level of acceptance among target
population
 Comply with treatment and minimal costs so
as not to outweigh its benefits
 Be a continuous process, not a one-off

8. Goal of DR screening
 To detect the maximum number of cases of
sight-threatening retinopathy and refer
these for further examination and
management by an Ophthalmologist
 Keeping those with non-sight-threatening
disease under periodic review

9. Goal of DR screening
 To detect the maximum number of cases of
sight-threatening retinopathy and refer
these for further examination and
management by an Ophthalmologist
 Keeping those with non-sight-threatening
disease under periodic review

10. Three-stage process
1. Macular single field digital retinal photography,
without mydriasis, for each eye.
2. If there is a technical failure, macular single field digital
retinal photography, with mydriasis for each eye.
3. If there is a technical failure with mydriatic digital
photography, biomicroscopy with a slit lamp is
performed.
4. Patients from with ungradable images have a 10.5%
incidence of sight threatening diabetic retinopathy.
Arrangements must be made within a screening
program for these patients to be examined by an
ophthalmologist.
5. Technical failures (i.e. ungradable images) must be
contained within the screening program in order to
prevent ophthalmology services from being
overwhelmed.

11. Three-stage process
1. Macular single field digital retinal photography,
without mydriasis, for each eye.
2. If there is a technical failure, macular single field digital
retinal photography, with mydriasis for each eye.
3. If there is a technical failure with mydriatic digital
photography, biomicroscopy with a slit lamp is
performed.
4. Patients from with ungradable images have a 10.5%
incidence of sight threatening diabetic retinopathy.
Arrangements must be made within a screening
program for these patients to be examined by an
ophthalmologist.
5. Technical failures (i.e. ungradable images) must be
contained within the screening program in order to
prevent ophthalmology services from being
overwhelmed.

12. Why is it important to screen for
diabetic retinopathy?
 DR is the most important preventable cause
of blindness & major cause of blindness in
people of working age
 DR is asymptomatic (silent)until it is in its
advanced stages (sudden drop of vision)
 Treatment of DR has a better prognosis if it
is done in the earlier stages
 When symptoms occur, treatment is more
complicated and often difficult with poorer
outcome

13. Why is it important to screen for
diabetic retinopathy?
 DR is the most important preventable cause
of blindness & major cause of blindness in
people of working age
 DR is asymptomatic (silent)until it is in its
advanced stages (sudden drop of vision)
 Treatment of DR has a better prognosis if it
is done in the earlier stages
 When symptoms occur, treatment is more
complicated and often difficult with poorer
outcome

14. Limitations of the diabetic
screening program 1/2
 Screening for diabetic retinopathy is a test;
therefore, it is not perfect. It does not find
every abnormality in every patient.
 Accelerated forms of diabetic retinopathy can
develop between screening intervals.
 Even with effective treatment performed to
the highest standards, some patients will not
respond.
 False positive/Negative results.

15. Limitations of the diabetic
screening program 1/2
 Screening for diabetic retinopathy is a test;
therefore, it is not perfect. It does not find
every abnormality in every patient.
 Accelerated forms of diabetic retinopathy can
develop between screening intervals.
 Even with effective treatment performed to
the highest standards, some patients will not
respond.
 False positive/Negative results.

16. Limitations of the diabetic
screening program 2/2
 Diabetic eye screening is not designed to detect
other eye problems. Patients with other eye
problems should be encouraged to see their own
doctor and not wait their diabetes eye screening
appointment.
 Not all images are gradable
 Communication between screening and
ophthalmology
 Communication with patients
 Human errors
 Grading
 Training

17. Limitations of the diabetic
screening program 2/2
 Diabetic eye screening is not designed to detect
other eye problems. Patients with other eye
problems should be encouraged to see their own
doctor and not wait their diabetes eye screening
appointment.
 Not all images are gradable
 Communication between screening and
ophthalmology
 Communication with patients
 Human errors
 Grading
 Training

18. Criteria for exclusion from
screening:
 A Patient who has made his/her own informed
consent
 A patient under the age of 12 years
 No-Perception-of-Light vision
 Terminally ill / deceased
 Has physical or mental disability preventing
either screening or treatment
 Currently under treatment of ophthalmologist
for management of diabetic retinopathy

19. The impact that screening may have
on the patient
a. The psychological impact that screening
might have on the patient
b. Importance of patients’ informed
decision making in a screening program

20. The psychological impact of
screening on the patient 1/3
 Screening by using retinal photography has been
shown in a number of studies to be an
acceptably sensitive test to screen for the
presence of any diabetic retinopathy in people
with diabetes who do not visit ophthalmologists.
 It is believed that screening modifies health
beliefs but had limited effect on behavioral
intentions, with patients of longer disease
duration being more reluctant to change their
self-management.

21. The psychological impact of
screening on the patient 1/3
 Screening by using retinal photography has been
shown in a number of studies to be an
acceptably sensitive test to screen for the
presence of any diabetic retinopathy in people
with diabetes who do not visit ophthalmologists.
 It is believed that screening modifies health
beliefs but had limited effect on behavioral
intentions, with patients of longer disease
duration being more reluctant to change their
self-management.

22. The psychological impact of
screening on the patient 2/3
 Unnecessary patient stress and anxiety may
be caused by:
 Missing disease or
 False positive findings
Ultimately, any of these might put patients off the
screening process.
 The public may have an unrealistic
judgment, that screening is expected to
guarantee prevention of disease or its
complications.

23. The psychological impact of
screening on the patient 2/3
 Unnecessary patient stress and anxiety may
be caused by:
 Missing disease or
 False positive findings
Ultimately, any of these might put patients off the
screening process.
 The public may have an unrealistic
judgment, that screening is expected to
guarantee prevention of disease or its
complications.

24. The psychological impact of
screening on the patient 3/3
 The screening program must ensure patients
have a realistic expectation of what the
program is designed to achieve.
 It should be emphasized that diabetic
retinopathy screening could not offer any
guarantee that a patient would never suffer
loss of vision.

25. The psychological impact of
screening on the patient 3/3
 The screening program must ensure patients
have a realistic expectation of what the
program is designed to achieve.
 It should be emphasized that diabetic
retinopathy screening could not offer any
guarantee that a patient would never suffer
loss of vision.

26. Importance of patients’ informed
decision-making in “screening”
 What is involved?
 Any risks?
 What happens if they test positive?
 How often they need to attend if they test
negative?
 How their information is stored and used?
 The potential consequences of choosing to
refuse screening

27. Patients’ decision-making
 An information booklet(s)/ leaflets for people
with diabetes and their families regarding eye
checks and treatment of diabetes-related eye
disease can help people to become involved
in making decisions about their treatment.

28. Patients’ decision-making
 An information booklet(s)/ leaflets for people
with diabetes and their families regarding eye
checks and treatment of diabetes-related eye
disease can help people to become involved
in making decisions about their treatment.

29. Procedures in a Screening Program
a. Components of any screening program for
diabetic retinopathy
b. Advantages and disadvantages

30. Components of any screening program
for diabetic retinopathy
 A screening program needs to be provided by
a multidisciplinary team of:
 Administrators
 Photographers
 Graders
 Ophthalmologists

31. Components of a screening program
 Administration
 Screening test
 Grading
 Referrals
 Treatment and follow-up
 Information system to manage the above
 Quality assurance

32. A screening program for DR will
include four-key components:
1. Call-and-recall, and program administration
(should include accurate patient register)
• Call for appointment time and date and details of what
happens at examination
• Call saying that they did not attend and requesting them
to make a another appointment
2. Digital photography
3. Grading of digital photographs: Photographers and
graders need to work closely together. In some
programs the photographers perform initial risk assessment whilst
the patient is present. In others they rotate between days out taking
photographs in the community and days at base grading images.
4. Assessment and treatment of screen-detected
retinopathy

33. A screening program for DR will
include four-key components:
1. Call-and-recall, and program administration
(should include accurate patient register)
• Call for appointment time and date and details of what
happens at examination
• Call saying that they did not attend and requesting them
to make a another appointment
2. Digital photography
3. Grading of digital photographs: Photographers and
graders need to work closely together. In some
programs the photographers perform initial risk assessment whilst
the patient is present. In others they rotate between days out taking
photographs in the community and days at base grading images.
4. Assessment and treatment of screen-detected
retinopathy

34. Call-and-recall
 Recall methods are essential to the continued success of regular
screening. A much higher number of people with diabetes will
have their eyes examined when reminded to do so.
 An assessment of a program’s effectiveness in reaching the
target population should be conducted periodically to evaluate a
screening program. Other issues that warrant the collection of
data from screening participants include the identification of
barriers to screening and information to monitor screening
outcomes.
 A measure of the success of the screening program will be the
proportion of people with diabetes screened each year. But, it
is recognized that screening rates depend on the decisions of
individual patients whether or not they wish to attend.The
program cannot be held responsible for those who choose not to
attend
 Diabetic screening should be part of a “comprehensive care for
people with diabetes” and embedded in the health service
system.

35. Call-and-recall
 Recall methods are essential to the continued success of regular
screening. A much higher number of people with diabetes will
have their eyes examined when reminded to do so.
 An assessment of a program’s effectiveness in reaching the
target population should be conducted periodically to evaluate a
screening program. Other issues that warrant the collection of
data from screening participants include the identification of
barriers to screening and information to monitor screening
outcomes.
 A measure of the success of the screening program will be the
proportion of people with diabetes screened each year. But, it
is recognized that screening rates depend on the decisions of
individual patients whether or not they wish to attend.The
program cannot be held responsible for those who choose not to
attend
 Diabetic screening should be part of a “comprehensive care for
people with diabetes” and embedded in the health service
system.

36. Screening program outcomes:
 No retinopathy
 Mild background retinopathy
exists
 Observable maculopathy exists
 Ungradable photograph, bad
photograph
 Recall in 1 year
 Recall in 1 year
 Recall in 6 months
 Call/Request to attend a slit lamp
examiner for further examination
 Referral to an ophthalmologist for further examination
 Report to GP with results of retinal screening/slit lamp examination
 Report to ophthalmologist with results of retinal screening
examination (maculopathy, severe background retinopathy,
proliferative retinopathy)

37. Advantages and disadvantages
Advantages:
 The service is delivered in locations with easy access and, offers a
wide choice of appointment times.
 Patients are able to have an eye examination at the same time
(Slit lamp is available).
 Capacity of screening is elastic as it can easily accommodate an
increase in number of screenings.
 Good quality of screening is assured by images being
independently re-evaluated.
 Software/Hardware enables the patient details to be effectively
delivered stored and graded and managed, including
communicating results to the patient and relevant health
professionals.
Disadvantages:
 Generally, photographic screening is often said to be that it
cannot detect macular edema as effectively as slit lamp.

38. Advantages and disadvantages
Advantages:
 The service is delivered in locations with easy access and, offers a
wide choice of appointment times.
 Patients are able to have an eye examination at the same time
(Slit lamp is available).
 Capacity of screening is elastic as it can easily accommodate an
increase in number of screenings.
 Good quality of screening is assured by images being
independently re-evaluated.
 Software/Hardware enables the patient details to be effectively
delivered stored and graded and managed, including
communicating results to the patient and relevant health
professionals.
Disadvantages:
 Generally, photographic screening is often said to be that it
cannot detect macular edema as effectively as slit lamp.

39. Quality assurance in Screening
 Internal and external quality assurance
 Performance monitoring

40. Aims of Quality Assurance
 Reduce the probability of error
 Ensure that errors are dealt with competently
and sensitively
 Help professionals and organizations improve
year on year
 Set and re-set standards
 Specific standards have been set for the program
at two levels
 Minimum acceptable
 Minimum achievable

41. Aims of Quality Assurance
 Reduce the probability of error
 Ensure that errors are dealt with competently
and sensitively
 Help professionals and organizations improve
year on year
 Set and re-set standards
 Specific standards have been set for the program
at two levels
 Minimum acceptable
 Minimum achievable

42. Categories of quality assurance
Internal quality assurance
 Part of the everyday processes in a screening
program
External quality assurance
 A completely objective assessment of program
with a comparative analysis of the outcomes.
 Quality assurance functions:
 Monitoring of program performance against quality
standards
 Administration of proficiency testing for all graders

43. Categories of quality assurance
Internal quality assurance
 Part of the everyday processes in a screening
program
External quality assurance
 A completely objective assessment of program
with a comparative analysis of the outcomes.
 Quality assurance functions:
 Monitoring of program performance against quality
standards
 Administration of proficiency testing for all graders

44. Auditing screening failures
 A screening program should include an audit of
screening failures, to review the screening history,
and previous images/results where appropriate.
 Screening failures may include:
 Patients who present with symptomatic diabetic
retinopathy in the interval between screens
 Patients who present with symptomatic diabetic
retinopathy but were not invited or did not attend for
screening
 Patients in whom there has been a marked and unexpected
deterioration in retinopathy since the previous screen (in
this case previous images should be reviewed to ensure that mis-grading
had not occurred).

45. Auditing screening failures
 A screening program should include an audit of
screening failures, to review the screening history,
and previous images/results where appropriate.
 Screening failures may include:
 Patients who present with symptomatic diabetic
retinopathy in the interval between screens
 Patients who present with symptomatic diabetic
retinopathy but were not invited or did not attend for
screening
 Patients in whom there has been a marked and unexpected
deterioration in retinopathy since the previous screen (in
this case previous images should be reviewed to ensure that mis-grading
had not occurred).

46. Monitoring/Evaluation
 Monitoring/Evaluation make judgments about the
value of a program.
 It is a process that determines whether a program
has achieved its goals and objectives.
 Monitoring is incorporated into the initial project
planning and take place throughout the program.
 Monitoring assesses:
 if the program is doing as planned
 Compares progress against objectives (preventing vision
loss from DR)
 The results from monitoring can identify what is
working (and what is not) to guide future decision
making and planning.

47. Monitoring/Evaluation
 Monitoring/Evaluation make judgments about the
value of a program.
 It is a process that determines whether a program
has achieved its goals and objectives.
 Monitoring is incorporated into the initial project
planning and take place throughout the program.
 Monitoring assesses:
 if the program is doing as planned
 Compares progress against objectives (preventing vision
loss from DR)
 The results from monitoring can identify what is
working (and what is not) to guide future decision
making and planning.

48. Monitoring/Evaluation
 Simply monitoring of referral rates is not sufficient. In the
case of diabetic retinopathy the rate of referrals in existing
photographic programs is between 3% and 10%.
 It is necessary to monitor:
 Disease-negatives, to ensure that disease is not being
missed
 Disease-positives, to minimize inappropriate referrals (and
associated patient anxiety). It is recommended that 10% of
disease negative cases should be re-graded independently as
part of the internal QA system.
 All disease-positive cases should be reviewed prior to issue
of a referral appointment.This will ensure prompt referral
to an ophthalmology clinic of serious disease without
swamping clinics and causing unnecessary alarm to
patients.

49. Monitoring/Evaluation
 Simply monitoring of referral rates is not sufficient. In the
case of diabetic retinopathy the rate of referrals in existing
photographic programs is between 3% and 10%.
 It is necessary to monitor:
 Disease-negatives, to ensure that disease is not being
missed
 Disease-positives, to minimize inappropriate referrals (and
associated patient anxiety). It is recommended that 10% of
disease negative cases should be re-graded independently as
part of the internal QA system.
 All disease-positive cases should be reviewed prior to issue
of a referral appointment.This will ensure prompt referral
to an ophthalmology clinic of serious disease without
swamping clinics and causing unnecessary alarm to
patients.

50. Evaluation
Evaluation takes place on three levels:
 Process evaluation: monitoring of activities and
strategies
 Impact evaluation: identifying achievement of
the project objectives (what has changed)
 Outcome evaluation: identifying achievement
of project goal.

51. Evaluation
Evaluation takes place on three levels:
 Process evaluation: monitoring of activities and
strategies
 Impact evaluation: identifying achievement of
the project objectives (what has changed)
 Outcome evaluation: identifying achievement
of project goal.

52. Process evaluation
Monitoring of activities and strategies
 Documenting activities:
 Health promotion activities undertaken
 Utilization of materials
 Collaboration with existing eye care resources and practitioners
that can be involved in screening
 Training sessions conducted
 Referral networks established
 Referral protocols developed
 Number of screening sessions conducted
 Estimate of local needs
 Quality and Satisfaction with Program
 Accuracy and quality of materials
 Participant satisfaction with program
 Staff and participant reaction to how the program is going.

53. Impact evaluation
Identifying achievement of the project objectives (what
has changed)
 Awareness and knowledge resulting from the health
promotion campaign
 Asking people who attend screening how they heard about
diabetic eye disease or the need for screening.
 Active involvement of health professionals in referral
and screening
 Numbers of health professionals who attend training or conduct
screening
 Compliance with referrals and utilization of the screening
program
 Monitoring of the quality of photographs by camera operators
and graders.
 Proportion of the target group(s) screened.

54. Outcome evaluation
Identifying achievement of project goal.
The reduction of vision loss in the population is not able to be
determined over a short time period or in a local project. This
can only be demonstrated through a population-based survey to measure
change from baseline data.
 Cases where vision loss has been avoided can be documented
through case studies.
 Stories of people newly diagnosed who have commenced
screening as soon as they were diagnosed with diabetes.
 Other cases of adolescents or adults who have had diabetes
for 10-20 years who have retained good vision as they have
attended for screening at least every two years.
 Contrast stories by ophthalmologists who have had people
referred with severe retinopathy with vision loss where vision
could not be restored.

55. Understand the factors which lead
to effective screening
a. Importance of maintaining accurate
registers on patients with diabetes
b. Factors that might lead to non-compliance
with screening and why this might be
important
c. Importance of monitoring the progress of
referred patients

56. Understand the factors which lead
to effective screening
a. Importance of maintaining accurate
registers on patients with diabetes
b. Factors that might lead to non-compliance
with screening and why this might be
important
c. Importance of monitoring the progress of
referred patients

57. Importance of maintaining accurate
registers on patients with diabetes
 The target population must be accurately
identified
 A register of all patients with diabetes within
the area covered by the screening program
must be created
 The register should be kept up-to-date at all
times

58. Barriers to screening (patients)
1/2
 Barriers related to cultural backgrounds
 They did not know of the need for eye exams
 The belief “nothing is wrong with my eyes”
 Poor access and transport to services
 Cost of the service
 Knowledge of who can screen for retinopathy
 Perception that their diabetes is “only mild”
 Other health priorities
 Don’t want drops in eyes

59. Barriers to screening (patients)
2/2
 Language and modes of communication
 Process been inadequately explained and they do not
understand the consequences
 They believe that, as they can see perfectly well, there
cannot be anything wrong
 Do not wish to find out that they may have a problem
 Housebound and physically unable to leave the house
 They may be housebound and able to leave the house
with assistance, but have no-one to accompany them
 They may have physical disabilities which prevent
successful photography or slit lamp and so they choose
not to attend.

60. Barriers to screening (Health
Professionals)
 Knowledge or attitudes
 Limited time and heavy case loads
 Limited knowledge of recommended
frequency for screening
 Lack of awareness of cultural views of health,
prevention and treatment
 Referral networks

61. Barriers to screening (Health
Services)
 Costs associated with attending
appointments
 Long waiting lists
 Availability of providers in rural areas
 Lack of recall or reminders for appointments
 Linkages between services or providers

62. Impact of screening on
Ophthalmology services
 The screening program will be expected to have some impact on
ophthalmology services.
 According to the DR screening services in Scotland “For a
population of 600,000 (prevalence of diabetes 2.5%) 8% would be
referred in the first year with referrals falling to about 3% only by
year 4. For the first 3,000 patients screened, the referral rate for
patients new to ophthalmology has been 4.2%... New referrals to
ophthalmology have consistently been in the range of 3-4% over an
eight-year period, screening 3,500-4,500 patients per annum”.
 Ophthalmology departments should discharge patients safely
back to the screening program after treatment.This is crucial to
allow ophthalmology departments to absorb the impact of the
screening program.
 Stable patients, who at present have to attend hospital
ophthalmology clinics for regular review, should in the future
attend the screening program.

63. Guidelines for patients attending
hospital ophthalmology clinics who
are suitable for transfer to the
screening program 1/2
 Patients with moderate background retinopathy can
be discharged to the screening program provided
there are facilities for 6-monthly follow-up within
the program.
 Patients with observable maculopathy can be
discharged to the screening program provided there
are facilities for 6-monthly follow-up within the
program.
 Patients with maculopathy or macular edema can be
discharged following successful laser treatment if
they no longer meet the criteria for referral.

64. Guidelines for patients attending
hospital ophthalmology clinics who
are suitable for transfer to the
screening program 2/2
 Patients with complete regression of proliferative retinopathy
can be discharged following successful laser treatment if they no
longer meet the criteria for referral.
 Patients with proliferative retinopathy who have had laser
treatment but who have residual new vessels can be discharged
to the screening program provided there is photographic
evidence that there has been no progression of the new vessels
over a period of 6 months.
 The presence or absence of laser burns should have no effect on
the decision to refer, monitor or discharge patients.
 All patients that are discharged must have baseline digital retinal
photographs sent to the screening program