Eye Conditions

Orbital Cellulitis

This is an infection of the structures which lie behind the orbital septum.

It is usually seen in young children. It is more severe than pre-septal cellulitis and will have worse symptoms (e.g., proptosis, ophthalmoplegia).

Patients usually have a history of an URTI (e.g., sinusitis) or pre-septal cellulitis.

Symptoms

Redness and swelling around eye with pain

Painful eye movements

Proptosis (bulging of the eye)

In preseptal cellulitis, you do not get reduced visual acuity or painful eye movements

Key tests

Bloods show raised inflammatory markers

Blood cultures to assess for bacteremia

CT with contrast of the orbit

Management

IV antibiotics

Cataract

This refers to clouding of the lens which leads to a progressive reduction in vision.

It is a significant cause of blindness worldwide.

It mostly occurs due to age, but can be accelerated by factors such as trauma, smoking, diabetes and steroids.

Symptoms

Progressive reduction of vision with increased glare and halos around lights

Faded colour vision, but there is not usually pain or severe irritation to the eyes

Absent red reflex – cataracts prevent light from getting to the retina, so red light is not reflected back

Key tests

Slit lamp examination shows visible cataract

Fundoscopy will show normal retina and optic disc

Management

Surgery (e.g., phacoemulsification uses ultrasound to break up the cataract)

AMD (age-related macular degeneration)

This is the most common cause of blindness in adults in the UK, which is due to progressive damage to the macula cells in the eye.

There is accumulation of drusen, small yellow deposits of lipids, between the retina and choroid, which damages the retina over time. This is known as dry AMD.

In addition, there can be abnormal vessel growth on the retina causing leakage of fluid/blood that further damages the retina. This is known as wet AMD.

Risk Factors

Age

Smoking

Positive family history

Symptoms

Blurred vision in the centre of the visual field, making it harder to see nearby objects

Difficulties in dark adaptation

Increased glare around objects

Key tests

Slit-lamp microscopy – identifies changes affecting the retina

If wet AMD is suspected – angiography is used to see new abnormal vessel growth

Management

For dry AMD – no curative treatment available

For wet AMD – VEGF inhibitors e.g., bevacizumab is used to prevent vessel growth 

Anterior Uveitis

This is a condition which describes inflammation of the uvea, the vascular middle layer of the eye that separates the outer fibrous sclera from inner neural retina layer.

It results in the accumulation of inflammatory cells and debris which appear as a fluid level (hypopyon) in the anterior chamber of the eye.

Risk factors

HLA-B27 arthropathies

Inflammatory bowel disease

Behcet’s disease

Symptoms

Acute onset of red eye with ocular pain and lacrimation

Pupil is small and irregular

Blurred visual acuity with photophobia and hypopyon

Management

Urgent referral to ophthalmology

Steroid eye drops and mydriatic eye drops (e.g., cyclopentolate)

Glaucoma

This is a group of diseases characterized by raised intraocular pressure which damage the optic nerve:

Open-angle (chronic) glaucoma

This is the commonest form of glaucoma due to clogging of the drainage canals.

The iridocorneal angle between the iris and cornea remains open but the trabecular network is obstructed raising intraocular pressure.

It develops slowly and is a lifelong chronic condition which progresses with age.

It is associated with a positive family history, diabetes, steroids and hypertension.

Symptoms

Decreased visual acuity over time with optic disc cupping

Peripheral visual field loss leading to “tunnel vision”

Management

Refer to ophthalmology

1st line medication is prostaglandin eye drops (e.g., latanoprost)

If unsuccessful, can use topical beta-blockers (timolol), carbonic anhydrase inhibitors (e.g., dorzolamide) or sympathomimetic eye drops

If uncontrolled, options include laser (trabeculoplasty) or surgery (trabeculectomy)

Angle-closure (acute) glaucoma

This occurs due to the acute blockage of drainage canals, causing an acute increase in intraocular pressure over a very short time frame.

There is a closed or narrow iridocorneal angle.

The disease progresses quickly and visual acuity decreases very noticeably.

Symptoms

Severe pain around the eye giving a hard red-eye

Decreased visual acuity with halos around lights

Semi-dilated non-reactive pupil and hazy cornea

Symptoms are more noticeable when the eye is dilated (in the dark)

Management

Urgent referral to ophthalmology

IV acetazolamide and pilocarpine drops (to constrict the pupil)

Painless Loss of Vision

There are a group of conditions which are characterised by a sudden painless loss of vision:

Retinal Detachment

This is where the retina detaches leading to an acute, painless loss of vision. It is usually due to a break in the retina which allows the eye fluid to get behind the retina.

It can be preceded by posterior vitreous detachment which is the separation of the vitreous membrane from the retina.

This can give rise to blurred vision, floaters and flashes of light in the visual field.

Symptoms

May have symptoms of vitreous detachment, e.g., floaters and flashes of light

Presents as a shadow that starts on the edge of the visual field moving inwards like a dark veil

Painless loss of vision

Straight lines may appear curved

Management

Surgery to restore the retina

Central Retinal Vein occlusion

This is a blockage of the central retinal vein (more common than arterial occlusion).

The incidence increases with age, but it also occurs secondary to conditions like glaucoma, hypertension and polycythaemia. 

Symptoms

Acute, painless loss of vision

It can be preceded by blurring of vision, worse on waking, which improves duringthe day

Key tests

Fundoscopy shows retinal haemorrhages

Management

Includes laser treatment and anti-VEGF injections

Central Retinal Artery Occlusion

This is a condition which occurs due to a blockage of the retinal artery, which originates from the ophthalmic artery and supplies the inner retina and optic nerve.

It is due to conditions which disrupt vascular structures, e.g., carotid artery disease, atherosclerosis, diabetes and giant cell arteritis.

Symptoms

Acute, painless loss of vision

Afferent pupillary defect (pupil constricts less in response to light)

Key tests

Fundoscopy shows an apparent red lesion amidst a pale surround retina (“cherry red spot”)

Management

Options include fluid removal to lower pressure, hyperbaric oxygen, ocular massage

Vitreous Haemorrhage

This is a caused by bleeding into the eye, which causes painless loss of vision.

The most common underlying cause is diabetes, which causes abnormal blood vessel growth on the retina. These vessels are much weaker and are prone to tearing.

It can also occur secondary to trauma, retinal tears or detachment.

Symptoms

Acute, painless loss of vision or blurry vision

May experience floaters, faint cobweb-like apparitions in the field of vision

Flashes of light in the peripheral vision

Key tests

Fundoscopy – inability to visualise the retina due to blood blocking the light

Management

If the haemorrhage is small, treatment may not be required

In severe cases, options include vitrectomy, cryotherapy and laser photocoagulation