Diabetic Retinopathy Flashcards
Examples of anterior segment complications of diabetes
- Aqueous Deficient Dry eye – microvascular damage to lacrimal gland due to high blood sugar levels so reduced aqueous production, if underlying diabetic neuropathy then leads to reduced lacrimal innervation, reduced corneal sensitivity so reduced reflex tearing and can develop aqueous deficient
- Diabetic neurotrophic keratopathy
- Epithelial fragility
- Delayed epithelial healing
- Superficial punctate keratopathy
- Persistent epithelial defects
- Recurrent corneal erosions
- Neurotrophic corneal ulceration
- Filamentary keratitis
- Descemet‘s folds
Corneal involvement is a common factor, need to look at cornea thoroughly
what is Diabetic Keratopathy
Diabetic keratopathy is when the cornea that does not have normal wound healing or healing mechanism which can lead to persistent or recurrent corneal epithelial defects and unresponsive to treatment especially when person’s blood glucose level is out of control or really high
why do more diabetic patients suffer from corneal complications
70% of diabetic patients suffer from corneal complications
Since diabetic cornea experiences 4-fold higher glucose level in diabetics
Examples:
1. Superficial punctate keratitis
2. Recurrent corneal erosion
3. Persistent epithelial defect (corneal)
4. Diabetic neurotrophic keratopathy
Diabetic Neurotrophic Keratopathy - what is it
- Occurs in up to 64% of diabetic patients
- Involves reduction of corneal nerve density so impaired corneal sensitivity - not enough nerves in cornea
- May lead to permanent vision loss
- Characterised by structural and functional changes of cornea
o Impaired corneal sensitivity
o Epithelial defects (loss of protective function)
o Impaired healing
o Corneal ulceration
o Loss of vision
what are the 3 stages of Diabetic Neurotrophic Keratopathy
o Three stages –
stage 1 could have no symptoms- could say eye is red than normal, reduced TBUT, could see punctate epithelial keratopathy. Need to catch at this stage.
cornea can be hazy in periphery
stage 3 stroma involved, ulceration, whole cornea oedematous, neovascularisation. High risk of perforation – could end up even more advanced infection – harder to control because of DM, such as endophthalmitis
When epithelial defect and does not heal properly and is slow healing or recurring, with the eye rubbing over it can lead to corneal ulceration and then vision loss.
corneal sensitivity in DM
Up to 55 % of diabetic patients have reduced corneal sensitivity.
Corneal sensitivity still difficult to measure and quantify. Need to consider if they want CLs!
When assessing cornea and adding NaFl,, does patient say eye is stingy once it goes in – shows cornea sensation, some reaction, does not mean if they don’t feel NaFl that they don’t have corneal sensitivity.
Not recommended to fit DM patients with CLs, fi already reduced corneal sensitivity and then training eye to forget anything on the eye with the cls, or only for occasional wear and monitor very frequently
Anterior Uveitis in DM
- Presenting feature
- Poor glycaemic control
- Type 1
- Advanced Type 2 (Neuropathy etc.)
- Acute
- Anterior
can be a presenting feature of undiagnosed diabetes, recurrent, thought to be because of disruption in blood retina barrier – increases inflammation, increases risk of anterior uveitis, seen in poorly controlled diabetics, advanced type 2 in older patients and type 1 for younger patients usually
cataract in DM
- Cortical
- Nuclear
- Snowflake
More prone to develop cataract earlier in DM
if someone had juvenile onset, type 1 mainly, and is difficult to control then snowflake cataract, would develop this at a young age as well
how many diabetics have DR
a third
main risk factors of DR
- Hyperglycemia – poor blood glucose level control, or varied control
- Hypertension – another vascular issue
- Diabetes duration – generally the longer the more likely to have DR
- Ethnicity (African, Hispanic, South Asian)
- Puberty and pregnancy (DM type 1) – if significant change in body then higher risk of DR
clinical signs of DR
- Microaneurysms
- Retinal haemorrhages – flame, dot or blot, dot haemorrhages are smaller and rounder, blot are larger and uneven
- Hard exudates – causes by lipid leaking from BVs due to damaged blood retinal barrier
- Cotton-wool spots – accumulation of axoplasmic debris within the bundles of ganglion cell axons, tells us those areas in the retina are ischemia – not enough blood and oxygen – indication of underlying nerve fiber layer damage
- Venous tortuosity and beading
- Neovascularisation in retina or in posterior vitreous, which can lead to tractional RD
- Tractional retinal detachment
- Macular oedema
History and Symptom: First Presentation DM
- Px may tell you that their vision fluctuates throughout the day – may be worse when they are hungry or after exercise.
General Health: - Px may tell you they are being investigated for diabetes – prediabetic
- They may be diet controlled (no meds)
Family History: - Who (immediate family) had DM? TYPE? Age of Onset? Any effect on this family members eyes?
History and Symptoms: Monitoring, General Health:
If Px is already diagnosed, you need to ask:
- Type
- Duration – shows risk, longer
- Medications
- Stability with meds/lifestyle
- Who monitors it? – may monitor themselves with home monitor or could be GP if new or uncontrolled.
- When was the last check-up with GP? – even if monitored by themselves, since have annual check up in most cases
- Are they attending DRS?
- If yes – when was it? Were they advised of any changes in the back of their eye?
- If no – any reason why not – accesses issue, nervous on going, any vlaid reason? Consider putting them on annual recall and monitoring them within your practice.
if they don’t want to go to DRS then should consider seeing them sooner like 12/12
refraction signs DM
Biggest indication (of blood sugar level vascular issue): Fluctuating visual acuity throughout refraction.
You should consider DM as part of your differential diagnosis whilst refracting if this is the case, especially if there are other risk factors.
anterior eye health DM
- Quantitative and qualitative evaluation of tear film
- Measurement of corneal sensitivity
- Treat any dry eye and monitor corneal defects
- Look for inflammation in the anterior chamber – may be asymptomatic
- Look for any structural changes in the lens
- Refer if persistent visual impairment
