OPHTHALMOLOGY
Microsoft Office User
[COMPANY NAME] [Company address]
,CATARACTS
AETIOLOGY PATHOPHYSIOLOGY
Ocular causes Any light-scattering opacity within the lens
- Trauma Can cause visual loss if extensive or lying on the visual
- uveitis axis
- high myopia Most treatable cause of blindness worldwide
- steroid eye drops
- intraocular tumour Lens is mostly made of water + protein. The protein is
arranged to let light pass through and focus on the
systemic causes retina. If the proteins clump together it can start to
- diabetes, other metabolic disorders cloud a small area of the lens, blocking some light from
- systemic steroids, chlorpromazine reaching the retina and interfering with vision
- XR
- Congenital rubella
- Atopic dermatitis
- Myotonic dystrophy CLINICAL FEATURES
- Down’s syndrome - Painless loss of vision
Risk factors - Glare
- Age - Change in refraction
- Smoking - Altered colour vision
- Long term UV exposure - Decreased VA (especially in bright light)
- FHx - Difficulty driving at night
- Dark silhouette against red reflex
- Loss of red reflex
DIAGNOSIS MANAGEMENT
Look for systemic cause if < 60 years, or unilateral Surgery – phacoemulsification
cataract Uses US to break up cataract and replace with an
Biometry to enable accurate intraocular lens power artificial intraocular lens
(IOL) calculatory
COMPLICATIONS OF SURGERY
1/1000 have reduced sign
1/10,000 lead to loss of eye
- Iris prolapse
- Posterior capsule opacification
o Decreased VA over months
o Treated with laser capsulotomy – hole created in posterior capsule in the pupillary axis
- Endophthalmitis – vitreal infection
- Cystoid macular oedema
o Severe decreased VA
o Treated with steroids, NSAIDs
- Vitreous loss and retinal detachment
, DIABETIC RETINOPATHY
SUMMARY PATHOPHYSIOLOGY
Affects 40% of diabetic population Microangiopathy with damage to small vessels.
T1DM > T2DM Intracellular accumulation of sorbitol cellular
damage.
Proliferative DR affects about 10% of the diabetic
population – T1DM particularly at risk - Death of pericytes
- Thickening of capillary BM
Risk factors - Loss of vascular smooth muscle cells
- Duration of diabetes - Proliferation of endothelial cells
- Poor diabetes control - Abnormal RBCs
- Pregnancy, sometimes associated with rapid - Increased plasma viscosity
progression All of which lead to capillary occlusion and leakage
- HTN
- Nephropathy Capillary non-perfusion causes retinal hypoxia
- Smoking release of VEGF neovascularisation
- Obesity Release of VEGF also causes breakdown in the blood-
retinal barrier which can cause diabetic macular
oedema
PRESENTATION
Visual symptoms CLASSIFICATION
- Asymptomatic 1. Non-proliferative DR
- Decreased VA 2. Diabetic maculopathy – foveal oedema,
- Distortion exudates, or ischaemia
- Floaters a. Most common cause of visual
Non-proliferative: dot/blot haemorrhages around impairment in diabetes (particularly T2)
the periphery, microaneurysms b. Diffuse – caused by extensive capillary
leakage
- Cotton wool spots
c. Local – focal leakage from
- Hard exudates
microaneurysms and dilated capillaries
- Blot haemorrhages
3. Proliferative DR – neovascularisation within 1 disc
diameter and/or new vessels elsewhere in the
fundus
MANAGEMENT 4. Advanced diabetic eye disease – tractional
Non-proliferative: observation retinal detachment, significant persistent
vitreous haemorrhage, neovascular glaucoma
Diabetic macular oedema
- Centre-spared = macular laser therapy
- Centra-involved = COMPLICATIONS
o VA < 6/9 = anti-VEGF injection - Retinal haemorrhage
o VA > 6/9 = observation - Vitreous haemorrhage
Proliferative DR = panretinal photocoagulation - Rubeosis iridis (formation of new blood vessels in
the iris)
Anti-VEGF injections can’t be used as it only lasts ~1
- Optic neuropathy
months (not practical). PRPC aims to decrease
- Cataracts
oxygen requirement of retina by destroying the
peripheral retina and leaving the macular –
preventing release of VEGF
It does cause a decrease in the visual field. Since the
peripheral retina is largely made of red cells –
ablation of the periphery means patient will be
night-blind.
Microsoft Office User
[COMPANY NAME] [Company address]
,CATARACTS
AETIOLOGY PATHOPHYSIOLOGY
Ocular causes Any light-scattering opacity within the lens
- Trauma Can cause visual loss if extensive or lying on the visual
- uveitis axis
- high myopia Most treatable cause of blindness worldwide
- steroid eye drops
- intraocular tumour Lens is mostly made of water + protein. The protein is
arranged to let light pass through and focus on the
systemic causes retina. If the proteins clump together it can start to
- diabetes, other metabolic disorders cloud a small area of the lens, blocking some light from
- systemic steroids, chlorpromazine reaching the retina and interfering with vision
- XR
- Congenital rubella
- Atopic dermatitis
- Myotonic dystrophy CLINICAL FEATURES
- Down’s syndrome - Painless loss of vision
Risk factors - Glare
- Age - Change in refraction
- Smoking - Altered colour vision
- Long term UV exposure - Decreased VA (especially in bright light)
- FHx - Difficulty driving at night
- Dark silhouette against red reflex
- Loss of red reflex
DIAGNOSIS MANAGEMENT
Look for systemic cause if < 60 years, or unilateral Surgery – phacoemulsification
cataract Uses US to break up cataract and replace with an
Biometry to enable accurate intraocular lens power artificial intraocular lens
(IOL) calculatory
COMPLICATIONS OF SURGERY
1/1000 have reduced sign
1/10,000 lead to loss of eye
- Iris prolapse
- Posterior capsule opacification
o Decreased VA over months
o Treated with laser capsulotomy – hole created in posterior capsule in the pupillary axis
- Endophthalmitis – vitreal infection
- Cystoid macular oedema
o Severe decreased VA
o Treated with steroids, NSAIDs
- Vitreous loss and retinal detachment
, DIABETIC RETINOPATHY
SUMMARY PATHOPHYSIOLOGY
Affects 40% of diabetic population Microangiopathy with damage to small vessels.
T1DM > T2DM Intracellular accumulation of sorbitol cellular
damage.
Proliferative DR affects about 10% of the diabetic
population – T1DM particularly at risk - Death of pericytes
- Thickening of capillary BM
Risk factors - Loss of vascular smooth muscle cells
- Duration of diabetes - Proliferation of endothelial cells
- Poor diabetes control - Abnormal RBCs
- Pregnancy, sometimes associated with rapid - Increased plasma viscosity
progression All of which lead to capillary occlusion and leakage
- HTN
- Nephropathy Capillary non-perfusion causes retinal hypoxia
- Smoking release of VEGF neovascularisation
- Obesity Release of VEGF also causes breakdown in the blood-
retinal barrier which can cause diabetic macular
oedema
PRESENTATION
Visual symptoms CLASSIFICATION
- Asymptomatic 1. Non-proliferative DR
- Decreased VA 2. Diabetic maculopathy – foveal oedema,
- Distortion exudates, or ischaemia
- Floaters a. Most common cause of visual
Non-proliferative: dot/blot haemorrhages around impairment in diabetes (particularly T2)
the periphery, microaneurysms b. Diffuse – caused by extensive capillary
leakage
- Cotton wool spots
c. Local – focal leakage from
- Hard exudates
microaneurysms and dilated capillaries
- Blot haemorrhages
3. Proliferative DR – neovascularisation within 1 disc
diameter and/or new vessels elsewhere in the
fundus
MANAGEMENT 4. Advanced diabetic eye disease – tractional
Non-proliferative: observation retinal detachment, significant persistent
vitreous haemorrhage, neovascular glaucoma
Diabetic macular oedema
- Centre-spared = macular laser therapy
- Centra-involved = COMPLICATIONS
o VA < 6/9 = anti-VEGF injection - Retinal haemorrhage
o VA > 6/9 = observation - Vitreous haemorrhage
Proliferative DR = panretinal photocoagulation - Rubeosis iridis (formation of new blood vessels in
the iris)
Anti-VEGF injections can’t be used as it only lasts ~1
- Optic neuropathy
months (not practical). PRPC aims to decrease
- Cataracts
oxygen requirement of retina by destroying the
peripheral retina and leaving the macular –
preventing release of VEGF
It does cause a decrease in the visual field. Since the
peripheral retina is largely made of red cells –
ablation of the periphery means patient will be
night-blind.
