Diabetic retinopathy and other retinal vascular disorders Flashcards
Leading cause of working-age adult blindness
Diabetic retinopathy
Type 1 DM risk
30% >10 years
90% >30 years
Type 2 DM risk
5% at dx
Diabetic retinopathy pathophysiology
Occlusion
Microvascular disease -> BM thickening + endothelial dysfx -> haematological changes -> thrombus -> retinal hypoxia -> ischaemia -> VEGF -> neovascularisation
Leakage
Oedema
Majority of diabetic retinopathy symptoms caused by
Macular oedema
Vitreous haemorrhage
Signs of diabetic retinopathy
Microaneurism Exudate Cotton wool spot Macular oedema Vitreous haemorrrhage Venous beading IRMA Neovascularisation
Diabetic retinopathy classifications
Background Preproliferative Proliferative Maculopathy Advanced disease
Background diabetic retinopathy
Microaneurism
Exudates
Dot blot haemorrhage
Preproliferative diabetic retinopathy
Cotton wool spots
Venous beading
IRMA
Proliferative diabetic retinopathy
NVD
NVE
Maculopathy
Cystoid macular oedema
w/wo other signs
Advanced diabetic retinopathy
Vitreous haemorrhage
Retinal detachment
NVI
Diabetic retinopathy screening
Ocular exam
VA
Dilated fundoscopy
Fundus camera
Refer if decreased VA or abnormal fundus
Diabetic retinopathy screening
Comorbidities
HbA1c control (DMI) BP control (DMII)
Diabetic retinopathy treatment
Control comorbidities (blood sugar, BP, cholesterol, lifestyle)
Metformin oral tx
Laser photocoagulation
AntiVEGF injection
Retinal vein occlusion epidemiology
> 50% occur in pt >65yo
Assoc with HT, dyslipidaemia, diabetic, smoking, contraceptive pill
Retinal vein occlusion pathophysiology
Raised IOP
Atherosclerosis
Hypercoaguability
Virchow’s triad
Central retinal vein occlusion
Occlusion at lamina cribrosa where v exits
Severe congestion (no blood exits therefore no blood enters)
Extensive oedema and haemorrhage
Blood and thunder
VA 6/60 to HM
RAPD present
Branched retinal vein occlusion
Occlusion at AV crossing
Severe congestion but only portion of retinal involvement
VA 6/9 to 6/60 and loss of vision over affected retina
No RAPD
Retinal vein occlusion treatment
Macular oedema - antiVEGF
Neovascularisation - antiVEGF or focal laser
Surgery for neovascular glaucoma
Retinal artery occlusion epidemiology
HT
Smoker
Dyslipidaemia
Cardiac pt
Inflammatory vasculopathies
Blood dysacrasia
Retinal artery occlusion pathophysiology
Embolic event
Permanent or temporary obstruction
Often carotid artery is the source
Retinal artery occlusion temporary obstruction
Transient monocular vision loss
Amaurosis fugax
Retinal artery occlusion permanent obstruction
Infarct in retina
Pale colour
Attenuated arteries
Permanent visual loss
Central retinal artery occlusion
Emboli obstruct in lamina cribrosa region
Cherry red spot
Extensive visual loss
Profound RAPD
Branch retinal artery occlusion
Sectoral vision loss
RAPD present
Retinal artery occlusion investigations
BP
HBA1C
Cardiac exam, ECG, carotid auscultation
ESR, CRP (giant cell arteritis)
Special:
Carotid imaging
Cardiac imaging
Haematological testing to exclude hypercoag
Retinal artery occlusion management
Treat comorbidities
Optimise patient
Retinopathy of prematurity
Prem/VLBW infant
O2 used postdelivery
Hyperoxia inhibits vessel growth and then hypoxic retina releases VEGF
Retinopathy of prematurity screening
<30/32 weeks
<1500g
Severe systemic illness
Retinopathy of prematurity investigation
Dilated fundoscopy w indirect opthalmoscope every 1-3 weeks until zone 3 vascularised
Retinopathy of prematurity treatment
Laser photocoagulation
Cryotherapy
AntiVEGF
Surgical vitrectomy
Hypertensive retinopathy clinical signs
Generalised narrowing copper/silver wiring AV nipping focal narrowing Flame haemorrhage Cotton wool spots Exudates (macular star) Microaneurism Papilloedema
Hypertensive retinopathy staging
1 - minimal retinal artery narrowing
2 - (1) + focal narrowing and AV nipping
3 - (1) + (2) + retinal haemorrhage, hard exudate, cotton wool spots
4 - (1), (2), (3) + optic n swelling + macular star
1/2 nonmalignant
3/4 malignant
Sickle cell retinopathy
Hb S+C abnormal while Hb A+B normal
Sickled RBCs not flexible enough therefore cause obstruction
Non-proliferative sickle cell retinopathy
Arterial occlusion
Venous occlusion
Salmon patch retinal haemorrhage
Black sunburst scars
Proliferative sickle cell retinopathy
Arterial obstruction -> AV malformation -> seafan neovascularisation -> vitreous haemorrhage -> retinal detachment
Sickle cell retinopathy treatment
Screen known pt regularly
Laser photocoagulation
Surgical vitrectomy