INCIDENCE PATHOPHYSIOLOGY EPIDEMIOLOGY CLINICAL EATURES CLINICAL PRESENTATION CLASSIFICATION (CSME) CAUSES RISK FACTORS HISTORY PHYSICAL EXAMINATION STAGE SLASSIFICATION PSYCHOLOGICAL COMPONENTS DIFFERENTIAL DIAGNOSIS ACTION PLAN PROTOCOL - T GUIDELINE SUMMARY LIMITATIONS OF PHYSICAL EXAMINATIONS PRINCIPLES PREVENTION MANAGEMENT

1. Capstone Project

2. • The incidence of CSME is reported to be correlated with the increase in the number of retinal
microaneurysms (Girach and Lund-Andersen, 2007) and the duration of the disease.
• American Caucasians with a diabetes duration of over 10 years:
1. Type 1 patients - 20.1%
2. Type 2 patients - 13.9%
• Australian population - as high as 7% per year
• Scandinavian population :
1. Type I diabetic patients over a 4-year period - 3.4%
• The 4-year incidence of CSME in : (Williams et al., 2004)
1. type I insulin treated diabetic patients - 4.3 %
2. type II insulin treated diabetic patients - 5.1%
3. type II noninsulin-treated patients - 1.3%

3. The hallmark of diabetes mellitus is hyperglycemia, and chronic hyperglycemia lies at the root of all
complications of diabetes through its detrimental effects on blood vessels, leading to vascular dysfunction and
eventually vascular occlusion. Diabetes is likely also a chronic low-grade inflammatory disease, a recent finding
that may have important therapeutic implications. Chronic inflammation may also promote vascular
dysfunction and occlusion.
Hypoxia is the natural consequence of vascular dysfunction, and local hypoxia occurs in diabetic eye disease as
a consequence of retinal vascular dysfunction. In response to local hypoxia, affected tissues in the retina and
elsewhere upregulate the production of growth factors, such as vascular endothelial growth factor (VEGF).
This action of VEGF may be mediated by reductions in the levels of occlusion at tight junctions within the retinal vessels, leading to impaired cellular
interactions and adhesion, with resulting breakdown of the blood-retina barrier and accumulation of extracellular fluid.
On a cellular level, hypoxia results in thickening of the basement membrane of the vascular endothelium, and
also in a reduction of the supportive pericytes lining retinal blood vessels. These changes also promote
incompetence of the retinal vasculature, with leakage of extracellular fluid and the manifestation of macular
edema.

4. • Diabetic retinopathy occurs in 1 out of 3 people with diabetes, with reported rates of DME reaching 7% in this
group of patients . In fact, DME is the leading cause of visual loss and legal blindness in people with diabetes.
• DME occurs in approximately 14% of diabetics and can be found in both type I and type II patients (Girach and
Lund-Andersen, 2007).
• Patients with DME present with a range of visual symptoms depending on the degree to which the fovea is involved and the
chronicity of the edema.
• If the macula center is not involved patients are rarely symptomatic.
• Some patients with central macular involvement have excellent acuity and no visual complains, presumably because of only
recent involvement of the center.
• Patients may complain of loss of color vision, poor night vision and washing-out of vision in bright sunlight with poor dark-
light adaptation.
• Metamorphopsia is often seen.
• Frequently, patients with center involved DME note fluctuation of vision from day-to-day or even over the course of a day.
• In some cases, the patient may relate such changes to fluid retention, hyper or hypoglycemia, or ambient lighting.
• On fundus examination with slit lamp biomicroscopy or contact lens, retinal thickening may present in some
commonly identified patterns. Focal edema often occurs associated with a cluster of microaneurysms,
sometimes surrounded by an incomplete ring of hard exudates.
• Clues include the height of the retinal blood vessels over the pigment epithelium, loss of the foveal
depression or even cystoids spaces. Other features sometimes seen with macular edema include variable loss
of retinal transparency, a large burden of microaneurysms and intraretinal hemorrhages, and dispersed flecks
of hard exudates.

5. • Macular thickening with or without hard exudates
as judged with stereobiomicroscopy
• thickening can occur in various patterns: focal,
multifocal, and diffuse areas of retina thickening
• Hard exudates (consisting of lipoproteins) in
various patterns, e.g., circinate rings
Clinically Significant Macular Edema (CSME) is seen when
one of the following occurs:
1) Retinal thickening at or within 500 microns or 1/3 disc
diameter of center of macula.
2) Hard exudates at or within 500 microns of the center of
the macula with adjacent retinal thickening.
3) Retinal thickening GREATER than 1 disc diameter in size
which is within 1 disc diameter from the center of the
macula.
It is important to bear in mind that a classification relying
on a retinal biomicroscopic patient examination, not
fluoresceinangiography, is the determination of the
existence of CSME.
 77-year-old man
 Blurred vision to 20/40 in his left eye from clinically
significant macular edema (CSME)

6. • DME begins when the blood glucose is not well regulated. High blood sugar consistently harms the
whole bodily organs, like heart, and the retina's tiny blood vessels.
• Without healthy blood vessels, your retina can't work the way it's supposed to.
• Your body tries to help out by making more of a protein called vascular endothelial growth factor, or
VEGF. But too much of it weakens those blood vessels. In time, they can tear and leak blood and
fluid into your retina. your retina will swell and get thicker, a condition called diabetic retinopathy.
• The leaking fluid also causes swelling in the macula, the place in the center of the retina that gives you
sharp, clear vision.
• Diabetes is the main cause of macular edema. But it can happen for other reasons, too, including
cataract surgery or other operations on your eyes, macular degeneration, swelling in the uvea (the
middle part of your eye), and blocked veins in your retina or damage from radiation. Some medicines
for diabetes, cancer, and multiple sclerosis can cause macular edema.
• The hallmark of diabetes Mellitus is hyperglycemia, and chronic hyperglycemia lies at the root of all
complications of diabetes through its detrimental effects on blood vessles, leading to vascular
dysfunction and eventually vascular occlusion.
• Diabetes is likely also a chronic low-grade inflammatory disease, a recent finding that may have
important therapeutic implications. Chronic inflammation may also promote vascular dysfunction and
occclusion.
• Hypoxia results in thicening of the basement membrane of the vascular endothelium, and also in a
reduction o the supportive pericytes lining retinal blood vessels.changes also promote incompetence
of the retinal vasculature, with leakage of extracellular fluid and the manifestatio of macular edema.

7.  NON-MODIFIABLE :-
• Duration of Diabetes : Cohort studies with the longest follow-up times found that almost all patients
with type 1 diabetes develop some degree of retinopathy if duration of disease exposure is long
enough.
• Pregnancy : DME can progress rapidly during pregnancy, especially in patients with type 1 diabetes.
 MODIFIABLE :-
• Hyperglycemia
• Hypertension
• Dyslipidemia
• Obesity
• Obstructive sleep apnea : A separate study on patients with CSME found high prevalence of sleep-
disordered breathing in these patients, but severity of sleep-disordered breathing was not
correlated with severity of DR or DME in this study.
• Nephropathy :Proteinuria is a good marker for the development of diabetic retinopathy.
• Anemia
• Glitazone usage (Despite their effect on blood glucose levels, they have been reported to worsen
DME )

8. • Specific inquiry of type of diabetes, the duration, and the degree of control.
• After 20 years of disease, nearly all patients with type 1 and 60% of patients with type 2 diabetes
have some degree of retinopathy. The risk increases with the duration of disease. Hence, diabetic
retinopathy is more likely to be present in patients older than 40 years.
• tighter control of blood sugar is associated with reduced incidence of diabetic retinopathy.
Glycosylated hemoglobin [HbA1c] should be less than 7%.
• patients with diabetic nephropathy should be observed more closely.
• Elevated blood pressure increases the risk of retinopathy; patients with diabetes and hypertension
may develop diabetic retinopathy with superimposed hypertensive retinopathy.
• Elevated triglyceride and lipid levels increase the risk of retinopathy, while normalization of lipid
levels reduces retinal leakage and deposition of exudates.
• diabetic retinopathy can progress rapidly in pregnant women, especially those with preexisting
diabetic retinopathy.

9. • Funduscopy under stereopsis and high magnification should be performed on every
patient with diabetes to assess for diabetic macular edema (DME) and diabetic
retinopathy.
• An indirect ophthalmoscope does not provide adequate magnification for the diagnosis
of diabetic macular edema.
• The status of the posterior hyaloid should also be determined. In CSME, the posterior
hyaloid is detached, taut, and thickened.
CIRCULAR AREA OF
STAGING
STAGE CLASSIFICATION

10. • OCT is now regarded as the most sensitive method in the detection and assessment of DME. The retinal map scan
is useful in locating the area with retinal thickening; single line scans are useful in detailing the specific DME
morphologic changes such as intraretinal cysts, subretinal fluid or detachment, and vitreoretinal traction.
However, because of the high costs of the imaging equipment as well as requirement of skilled training of
ophthalmologists, assessment of DME by OCT is currently considered feasible only for countries with high
resources.
• Fluorescein angiography does not aid in the diagnosis of clinically significant macular edema (CSME) but should
be performed if treatment of CSME is being considered. Fluorescein angiography distinguishes and localizes areas
of focal versus diffuse leakage, thereby guiding the placement of laser photocoagulation. The proximity of the
leakage to the foveal avascular zone should be noted.
• Color stereo fundus photographs provide an opportunity to evaluate long-term changes in the retina.
 FA of the Left Eye: confirmed the presence of leaking microaneurysms centered supranasal to the
fovea.
 OCT : minimal thickening in the right macula, but identifies foveal-involving macular edema and
subfoveal fluid in the left eye.
 FUNDUS PHOTOGRAPHY : highlights his bilateral parafoveal microaneurysms, which were more
pronounced in the left eye.

11. • The findings of a study demonstrate that severe NPDR or PDR and moderate or severe
vision impairment, but not DME, were independent risk factors for depressive symptoms
in people with diabetes.
• The same study showed that Diabetic macular edema was associated with lower
treatment satisfaction.
• association between DR or DME and anxiety was not observed in that study.
• Branch Retinal Vein Occlusion (BRVO)
• Central Retinal Vein Occlusion (CRVO)
• Exudative (Wet) Age-Related Macular Degeneration (AMD)
• Hypertension
• Pseudophakic (Irvine-Gass) Macular Edema
• Uveitis Evaluation and Treatment

12. • Informed consent.
• Attitudes towards DME treatment adherence appear to mirror patients' views and health behaviours in
relation to the management and care of their own diabetes.
• Text message reminders could be more widely utilised to reinforce and encourage good patient attendance for
scheduled appointments and minimise ‘did not attend' rates.
• Nurse-led structured education programmes encourage people to manage modifiable risk factors for onset
and progression of diabetic eye disease, by optimising control of blood glucose levels, blood pressure and lipid
management.
• The main modifiable risk factors for type 2 diabetes are overweight and obesity, insufficient physical activity
and unhealthy dietary practices.
• Smoking cessation is stressed, as is the importance of regular eye examination for early identification and
initiation of care for patients with retinopathy.
 ASSISTING :
 GENERAL :

13.  SUSPECTED DME IN DIABETIC PATIENTS :
• People living with diabetes are advised to have a comprehensive dilated eye exam at least once a year, or more
often as directed by the eye doctor. If blurred vision occurs, the patient should visit an eye doctor immediately. At
the visit, the eye doctor will conduct the following tests.
• Visual acuity - Although visual acuity does not aid in the diagnosis of CSME—initially, at least, patients may have a
visual acuity of 20/20—it is an important parameter in following the progression of CSME.
• Dilation - The eye doctor will dilate, widen the pupil of the eye, with eye drops to allow a closer look at the inside of
the eye. If the eye doctor suspects DME, then the following tests may be conducted:
1. Optical coherence tomography (OCT) - The OCT examination provides a cross sectional image of the eye which can
show if the macula is thickened or if fluid is leaking.
2. Fluorescein angiography - During this test, a dye is injected into the arm that “lights up” the blood vessels in the
eye while multiple photos are taken of the back of the eye. These images will show if there are new blood vessels
in macula and /or there is leaking of dye to determine if an individual has DME.
 After receiving the results from the diagnostic tests, the ideal treatment would have been intravitreal injections.
 The patient was extremely averse to needles, and he also had difficulty returning to the office for regular visits.
 Thus, we decided to proceed with the focal laser.

14.  TREATMENT :
The treatment plan is based oe presenting complaints, findings on diagnostic test
and patient's choice.
• The ETDRS conclusively demonstrated that focal/grid laser photocoagulation
was safe and effective in reducing vision loss due to DME.
• Significant visual improvement is uncommon.
• Photocoagulation reduced the risk of moderate visual loss from diabetic
macular edema by 50%, from 24% to 12%, 3 years after initiation of treatment.
• the technique involves placement of light, small (around 50 micron) laser
burns only within thickened areas of the macula, including direct (focal)
treatment of microaneurysms as well as spots scattered approximately two to
three burn widths apart (grid) within other areas of edema not accounted for
by microaneurysms.
• In addition to the traditional argon or diode laser used for macular
photocoagulation, several newer laser technologies are being evaluated. One
of these is a navigated laser photocoagulator (NAVILAS) that integrates a
scanning laser slit camera with fluorescein angiography and employs computer
aided steering of the laser.
BEFORE
AFTER FOCAL LASER
PHOTOCOAGULATION

15. • Mounting evidence exists that inflammation plays a significant role in the
development of diabetic macular edema. Given the apparent role of
inflammation in the pathogenesis of DME, steroids have more recently
been utilized for the treatment of DME.
• Their mode of action may be largely through their ability to inhibit the
expression of VEGF.
• The anti-inflammatory, angiostatic, and antipermeability properties of
these compounds have gained interest in chronic retinal conditions such
as DME.
• Several intravitreal steroid-releasing implants have been designed in an
attempt to provide longterm drug delivery to the macular region. These
include nonbiodegradable and biodegradable dexamethasone,
fluocinolone acetonide, and TA implants.
• Because of its central role in the pathogenesis of DME, VEGF (Vular
Endothelial Growth Factor) was a logical target for therapy.
• Several anti-VEGF agents are available. The first anti-VEGF agent used in
ophthalmology was pegaptanib (OSI Pharmaceuticals, Long Island, NY,
USA).
• RANIBIZUMAB, BEVACIZUMAB
 FOCAL LASER TREATMENT :
• A whitening of microaneurysms with 50- to
100-μm spots for a duration of 0.1 s. 2.
• Repeat focal burns are applied, if needed, to
obtain the desired effect, especially for
microaneurysms larger than 40 μm.
• Retreatment is required if macular edema
persists and the above-mentioned criteria
are not met.
• Clusters of microaneurysms could be treated
with larger and confluent spots (200–500
μm), if lesions are not located within 750μm
from the center of the macula.
• Post-operative treatment :
1. Investigate long-term visual acuity and
macular thickness on OCT post-treatment.
2. Additional treatment is recommended if 4
months following initial treatment, residual
CSME with treatable lesions is seen on
examination.
3. Intervals between laser sessions need to
be at least 4 months

16. DRCR.net Protocol T, which looked at the efficacy of Eylea (aflibercept), Lucentis
(ranibizumab) and Avastin (bevacizumab) in the treatment of diabetic macular edema.
INTRAVITREAL
ANTI-VEGF
INJECTIONS
FOR 6 MONTHS
• if there’s
persistent edema,
you perform laser
• but you don’t
keep giving
injections after six
months if it’s not
improving.
• there’s been
gradual
improvement at six
months, you don’t
do the laser
• but instead keep
giving the
injections

17. • Diabetic macular edema is an additional important vision-threatening manifestation of DR
that is assessed separately from the stages of DR because DME can be seen in eyes at any
DR severity level and can run an independent course.
• Conventionally, based on the International Classification, DME has been defined and
classified based on a clinical examination or retinal photography results according to its
proximity to fovea.
• In the current guidelines, the definition and classification of DME are updated with
information from OCT, if available :
1. No DME :- absence of retinal thickening or hard exudates in the macula region.
2. non–center-involving DME :- retinal thickening in the macula that does not involve a
central subfield zone that is 1 mm in diameter.
3. center-involving DME :- retinal thickening in the macula that involves a central subfield
zone that is 1 mm in diameter.
• The determination of DME severity based on these 3 categories also will determine the
need for treatment and follow-up recommendations.
• It is important to note that advanced stages of DR and DME may be present even in
patients who are not experiencing visual symptoms.

18. • Although many current screening programs are efficient in detecting referable DR, the accurate diagnosis of DME is
more challenging.
• An especially problematic aspect of two-dimensional fundus photography for DME detection is the inability to reliably
identify retinal thickening.
• The English National Screening Program (ENSP) for DR employs three photographic markers, namely
1. exudates within one disc diameter of the fovea,
2. circinates within the macula, and
3. microaneurysms or hemorrhages within one disc diameter of the fovea associated with best corrected visual acuity of
worse than 6/12, as surrogates for DME.
• This approach, while reasonable within the limits of currently used imaging platforms, has limited diagnostic accuracy.
Only 17% of patients with hemorrhages or microaneurysms within one disc diameter of the fovea and reduced visual
acuity had thickening on macular OCT, while only 6% had macular edema.
• Similarly, only 27% of those with macular exudates within one disc diameter of the fovea or circinates within two disc
diameters of the fovea had thickening on macular OCT.
• A cross-sectional observational study from Hong Kong recorded a false-positive rate of 86.6% for macular edema using
conventional fundus photography screening methods. Among eyes proven to have macular edema on OCT,
approximately one quarter to one-third are missed by fundus photography screening .
• A cost-effectiveness study of DME screening in Hong Kong found that although the screening cost per patient increased
by 35% if OCT was performed on all patients undergoing color fundus photography, the cost per quality-adjusted life-
year was reduced by 45% (RW, unpublished).

19. Practice
• Foster closer working relationships between diabetes management, general practitioners, and
ophthalmology specialties.
• Consider the benefits of establishing a dedicated DMO eye clinic service for management and follow-up
of patients with diabetic eye disease, for example, facilitate integration of a DSN-led review service and
enhance efficiency of diabetes care.
• Explore aspirations and opportunities to expand the role of the DSN in the hospital eye clinic, with the
specialist nurse acting as the main hub between ophthalmology, endocrinology, diabetology, and
primary care services/support.
• Tailor clinical practice and follow-up initiatives to improve treatment adherence in DMO.
• Set realistic patient expectations when initiating treatment of DMO.
• Perform a regular audit of practice outcomes and benchmark performance, preferably using an EMR
system.

20. Management
• In general, the modified Early Treatment Diabetic Retinopathy Study focal or grid laser photocoagulation protocol has
been proposed as a preferred protocol for laser treatment of clinically significant macular edema.
• Although clinically significant macular edema continues to be used widely, the guidelines recommend
DME be classified into center-involving and non–center-involving DME according to clinical findings and
OCT results where available.
• Patients with non–center-involving DME may be observed until there is progression to central involvement, or focal laser
can be performed to treat leaking microaneurysms if DME is threatening the fovea, according to the modified Early
Treatment Diabetic Retinopathy Study focal or grid laser photocoagulation protocol.
• No treatment should be applied to lesions closer than 300 to 500 μm to the center of the macula.
• Treatment of Center-involving Diabetic Macular Edema with Anti–Vascular Endothelial Growth Factor Agents and
Steroids :
1. Although there are different treatment regimens, the guidelines recommend a regimen that includes an initiation of monthly loading-dose injections followed by
treatment interruption and reinitiation based on visual stability and OCT findings.
2. Patients should be monitored almost monthly with OCT to consider the need for treatment.
3. Typically, the number of injections is 6 to 8 in the first year, 2 or 3 during the second year, 1 to 2 during the third year, and 0 to 1 in the fourth and fifth years of
treatment.
4. For eyes with persistent retinal thickening despite anti-VEGF therapy, consider laser treatment after 24 weeks.
5. In countries with low or intermediate resources, where possible, physicians can consider off-label alternatives such as bevacizumab (Avastin) to more expensive
drugs such as ranibizumab (Lucentis) or aflibercept (Eylea). Otherwise, focal or grid laser treatment should be considered as a primary method of treatment for
DME in low- or intermediate-resource settings.

21.  In general population : by preventing development of risk factors -
• Obesity, inactivity
• Diabetes
• Hypertension
• Hyperglycemia
• Dislipidemia
• regular body checkup
 In diabetic/high risk patients :
• Regular exercise regimen
• Well controlled diabetes, hypertension, and hypercholesterolemia.
• Regular eye checkups to check for development of DME, DR etc.
• Diet modification
• Check levels of HbA1c (Glycated Hemoglobin), Hemoglobin (anemia exacerbates diabetic
retinopathy, may be associated with diabetic nephropathy), Fasting Blood Sugar (FBS), Post
Prandial Blood Sugar (PPBS), Urea, Creatinine, Lipid Profile, Blood pressure, urinary microalbumin.

22. If you or someone you know has lost some sight to DME, low vision aids can help you stay
independent.
Special training, called vision rehabilitation, can provide skills for living with low vision. A low
vision specialist will help determine the right combination of aids for your needs. Ask your eye
doctor about the possibility of seeing a low vision specialist.
Low vision aids include:
Magnifying glasses, screens and stands
Telescopic lenses
High-intensity reading lamps
Large-print newspapers, magazines and books
Close-circuit TVs that magnify a printed page on screen
Computers and tablets