Systemic Disease Flashcards
Ocular complications of diabetes can be reduced by
Early detection/monitoring
Good diabetic control
Modification of risk factors - blood sugars, lipids, blood pressure, stop smoking
Ocular complications of diabetes
Diabetic retinopathy Diabetic maculopathy Extra-ocular muscle palsy Retinal vascular occlusions Cataracts
Diabetic retinopathy
Characteristic retinal abnormalities that occur throughout the retina
Include retinal micro-haemorrhage, exudates (hard exudate are lipid deposits), cotton wool spots
Diabetic maculopathy
Characteristic macula abnormalities
Most commonly macula oedema, exudates, retinal thickening and ischaemia
Starts with slight central visual loss but is often progressive
Major cause of vision loss in diabetic retinopathy
Macula oedema is clinically significant, and should be treated if
- If there is retinal thickening/exudates within 1/3 optic disc diameters from the centre of the macula
- If there is one disc area of retinal thickening or more, part of which is within one disc area of the centre of the macula
Diabetic extra-ocular muscle palsy
Diabetes can cause an isolated 3rd, 4th or 6th nerve palsy with pain around the eye
Diabetic 3rd nerve palsy spares the pupillary function
Diabetes and cataracts
Posterior subcapsular cataracts are frequently seen in diabetics
Diabetic retinopathy - risk in diabetic patients
20yrs after diagnosis 95-100% type 1s and 60% of type 2s will show retinopathy
30 years after diagnosis 30% of type 1 and 3% type 2 will have proliferative disease
Proliferative disease (proliferative diabetic retinopathy)
new vessel growth in the disc and elsewhere in the retina
Loss of sight in diabetes can be due to
Macula oedema Macula ischaemia Haemorrhage from new vessels Tractional retinal detachment Field loss due to laser treatment
Causes of diabetic retinopathy
Its due to hyperglycaemia
Clinical signs are due to small vessel occlusion, increased vascular permeability and changes in vessel walls die to loss of pericyte cells
Proliferative disease is caused by VEGF from ischaemic retina
Vitreous haemorrhage
Second most common cause of visual loss in diabetic retinopathy
Can cause acute vision loss and floaters
Retinal signs of diabetic retinopathy
Micro-aneurysms Dot & blot haemorrhages Exudates & Cotton wool spots Retinal oedema and thickening Neovascular and venous changes --> new vessels at the disc (NVD) and elsewhere (NVE)
Ocular ischaemia syndrome
A rare disease which occurs as a result of atherosclerotic vessels, generally the internal carotids.
The resulting ischaemia causes retinopathy and produces similar signs to diabetic micro vascular ischaemia
Investigating diabetic retinopathy
Duration and type of diabetes - HbA1c
Smoking
Other diabetes associated disease
Visual symptoms and past eye disease/treatment
Check red reflex for cataracts then dilated fundoscopy
Management of diabetic retinopathy
Screening of diabetic patients
Control diabetes and risk factors
Refer to ophthalmologist if - severe non-proliferative/proliferative retinopathy or maculopathy
Treatment of diabetic retinopathy
Classify the retinopathy - monitor. Treat any associated disease
PRP for new vessel growth,
Focal macula laser to reduce macula oedema, also Intravitreal anti-VEGF injections (ranibizumab) but multiple may be needed
Vitrectomy surgery is occasionally used for vitreous haemorrhage or relieve tractional retinal detachment
fluorescein angiography
Used to identify leaking new blood vessels and oedema
Classification of diabetic retinopathy
Mild non-proliferative DR -> Moderate non-proliferative DR ->
Severe non-proliferative DR -> Very severe non-proliferative DR ->
Non-high risk proliferative DR -> High risk proliferative DR -> Advanced proliferative DR -> Maculopathy
More recently UK ophthalmologists have started using
A system like tumour grading Retinopathy - R0, R1, R2, R3 or R4 Maculopathy - M0 or M1 Photocoagulation - P0 or P1 Unclassifiable - U
Thyroid eye disease - introduction
An inflammatory disease affecting the extra ocular muscle and the orbital connective tissues
There is an initial inflammatory stage followed by an inactive fibrotic state
Thyroid eye disease - epidemiology
An idiopathic autoimmune disorder - usually associated with hyperthyroidism but can occur in normal or hypothyroid
Peak incidence at 30-50yrs, more common in women
Worst cases are smokers, males and older people
Can lead to sight threatening optic neuropathy or exposure keratopathy
NOSPECS
A classification of the severity of symptoms:
(1) No symptoms or signs (5) Extraocular muscle palsy
(2) Only lid retraction +- lid lag (6) Corneal disease
(3) Soft tissue involvement (7) Sight threatening optic
(4) Proptosis Neuropathy
Thyroid eye disease - symptoms
Conjunctival injection & redness
Dryness, watering
Photophobia, Visual loss & Diplopia
Thyroid eye disease - history
Smoking
Family history of thyroid eye disease
Thyroid eye disease - signs
Conjunctival inflammation/chemosis
Upper lid retraction +- lid lag on looking down
Proptosis and Lagophthalmos
Reduced eye movements due to muscle palsies (inferior rectus)
If severe - Exposure keratopathy and optic neuropathy
Proptosis
Forward bulging of the globe in the orbit
Lagophthalmos
Inability to completely close the lids
Exposure keratopathy
Drying of the inferior part of the cornea due to incomplete lid closure
Symptoms of optic neuropathy
Reduced visual acuity
Reduced colour vision
Visual field defects
Thyroid eye disease - Investigations
Thyroid function tests and TSH
CT of orbit if uncertain, or to check for optic nerve compression
Thyroid eye disease - management
Refer to endocrinologist to manage systemic thyroid disease
Exposure keratopathy –> artificial tears
Elevate the head at night if eyelid oedema is a problem
May require systemic steroids –> must monitor IOP
Radiation can be used if that doesn’t work
Ocular symptoms of MS
Optic neuritis –> inflammation of the optic nerve is common symptom of MS
visual field defects
Cranial nerve palsies -> most commonly the 6th
Nystagmus
Optic neuritis in MS
Dysfunction developing over hours/days - painful eye movement
Variable reduction in visual acuity, Visual field defects & reduced colour vision (red desaturation because red vision goes first)
Typically 18-45yrs
Uhotoff’s sign
Uhtoff’s sign
Worsening of symptoms on exercise or increased body temperature –> symptoms are worse in the bath
Optic neuritis in MS - signs
RAPD
Colour vision defect
Visual field defect
May have swollen optic discs –> may not if inflammation is further back –> retrobulbar optic neuritis
Optic neuritis in MS - investigations
Ask about - age, duration/nature of visual loss, previous episodes, pain on moving the eye
Check for any other focal neurological signs
Optic neuritis in MS - management
Quantify deficit –> test pupils and eye movements, check level of red desaturation, confrontation visual field testing, fundoscopy
Full neurological exam
Refer to neurology –> MRI to confirm
Ocular problems in immunocompromised patients
Most commonly due to HIV –> varies with severity of compromise/infection
CD4 count >1000cells/mL is normal, CD4 count <50 is very low with high risk of CMV retinitis or other infections
When seeing a patient with HIV about their eyes you should check
Acuity and function
Eyelids and the external eye
Dilated fundoscopy including the peripheral retina
Ask about systemic illnesses and duration of HIV
CMV retinitis
Normally causes subacute infections in the salivary glands
Ocular infections only in the immunocompromised
On fundoscopy:
Para-vascular (following the vessels) opacification with associated haemorrhage
Blepharitis
An eye condition characterised by chronic inflammation of the eyelid which is usually self-limiting
Can be caused by staphylococcal species
Presents with sticky debris at eyelash roots, secondary punctate corneal erosions and may have conjunctival hyperaemia
Mollescum contagiosum
A condition caused by a poxvirus infection causing a small eyelid nodule, mild mucoid discharge and an inferior fornix follicle
Occurs in immunocompromised and immunocompetent patients
Consider in cases of recurrent or refractory conjunctivitis
HIV retinopathy
A condition characterised by retinal possible micro-haemorrhages with cotton wool spots on fundoscopy
A rare condition of unclear Pathophysiology
Toxoplasmosis of the retina
Common parasitic infection which is only active in the retina of immunocompromised patients
On fundoscopy: dark areas of older disease and active disease appearing as white retinitis
Spread by cats
Conjunctival kaposi sarcoma
A condition characterised by a red-violent nodule on the eyelid which is associated with HIV
Hypertensive retinopathy
Similar to hypertensive changes elsewhere in the body but easier to see
A serious complication of uncontrolled hypertension
Hypertensive retinopathy - fundoscopy signs
cotton wool spots due to retinal ischaemia
hard yellow lipid exudates, ‘copper and silver wiring’
flame haemorrhages in the retinal nerve fibre layer
macro-aneurysms (red dots), macula oedema, optic disc swelling, venous nipping at arteriovenous crossings,
Symptoms of hypertensive retinopathy
Usually asymptomatic but can experience visual loss
Copper and silver wiring
A fundoscopy sign of hypertensive retinopathy
Vessels have an altered reflex giving a different appearance
A hard sign to detect in practice
Differential diagnosis for hypertensive retinopathy
Ask about control and measure blood pressure
Diabetic retinopathy –> exclude by history and check BM
Diabetic/hypertensive retinopathy look similar and can co-exist
Consider Retinal vein occlusion
Hypertensive retinopathy - treatment
Control blood pressure
Hypertensive retinopathy - classifications
Grade 0 - normal
Grade 1 - arteriolar narrowing
Grade 2 - focal arteriolar narrowing + arteriovenous nipping
Grade 3 - haemorrhages, exudates and cotton wool spots
Grade 4 - grade 3 but with disc swelling
