Ophthalmology: Sub-specialty—Eyelid, lacrimation and orbit

Common eyelid lumps

Eyelid lumps are common and include benign cysts and tumours as well as malignant skin and adnexal tumours. Tumours can arise from the skin, the deeper layers of the eyelid, the conjunctiva or the orbit.

Aims

• Recognize a chalazion and understand its treatment.
• Recognize a basal cell carcinoma and distinguish it from a squamous cell carcinoma.
• Treat periocular basal cell carcinoma.

Differential diagnosis of periocular tumours

Many different lumps are found on the eyelids. An incision or excision biopsy is often required for histological analysis.

• Benign: chalazion, papilloma, retention cyst and sebaceous cyst.
• Malignant (in order of prevalence):
  ○ basal cell carcinoma (BCC)
  ○ squamous cell carcinoma (SCC)
  ○ sebaceous gland carcinoma (SGC)
  ○ malignant melanoma (MM)
  ○ Merkel cell tumour
  ○ other rare tumours (e.g. tumours of the sweat gland).

Benign lumps

Chalazion or meibomian cyst

There are at least 27 meibomian glands in each eyelid. The meibomian glands secrete oil and if the oil becomes too thick, for instance in blepharitis and meibomianitis, a single duct can obstruct. Giant cells go in to try to remove the oil, but can accumulate and form a chalazion.
The eyelid should be everted to see if there is a typical granuloma or grey appearance of the chalazion and to exclude other tumours.
A chalazion can be inflamed or quiet. Initial treatment of an inflamed chalazion is by hot compresses and topical antibiotic ointment four times a day for 2 weeks. If the lump persists as a quiet chalazion, surgical incision and curettage (I&C) is done.

If an assumed chalazion recurs, particularly in an older person, do an incisional biopsy urgently for histopathological analysis as this may be a sebaceous gland carcinoma (meibomian gland carcinoma), a highly malignant tumour.

Solar keratosis (actinic keratosis)

These are dry scaly patches due to dysplastic intraepidermal proliferation of atypical keratinocytes, and they occur on the face in older, fair-skinned persons who have lived in sunny climates. There is a low risk of malignant transformation into SCC. Fortunately, many solar keratoses regress spontaneously over 1–2 years, but 15% recur. Treatment is with cryotherapy or 5-fluorouracil.

Malignant lumps

Basal cell carcinoma (‘rodent ulcer’)

BCC is the commonest periocular malignant tumour. It occurs most frequently on the lower eyelid, the medial canthus, the upper lid and lastly the lateral canthus. It is typically a nodular pearly lump with no hair or lashes on it, with telangiectatic blood vessels. The central zone may bleed and ulcerate. It is usually nodular with distinct borders but can be morphoeic and have indistinct margins. BCC grows slowly by direct extension and destroys tissue locally. It can invade the orbit if neglected or inadequately treated. Early treatment is recommended by first doing an incisional biopsy to make the diagnosis and an excisional biopsy with a 2–4 mm margin of clear tissue or Mohs’ micrographic surgery to completely remove the tumour.
BCC does not metastasize. After surgical excision there, the oculoplastic surgeon does the eyelid reconstruction. Cryotherapy and radiotherapy are occasional treatment options.

Mohs’ micrographic surgery

Mohs’ micrographic excision of BCC is a special technique to remove the BCC with frozen sections of the deep bed of the tumour to ensure complete excision. It is done by dermatological surgeons especially trained in the technique. It provides good clearance of tumour with maximum normal tissue preservation and low recurrence; therefore, it is ideal for the eyelids where complete tumour excision and tissue preservation for reconstruction are essential.
Mohs’ micrographic excision is also used for SCC and meibomian cell carcinoma.
An oculoplastics-trained ophthalmologist does the periocular reconstruction after Mohs’ micrographic excision.

Squamous cell carcinoma

SCC is rarer than BCC but is more rapidly growing and has a greater potential for spread, especially perineurally. It is a red lump with a variable appearance. It is much more common in immunosuppressed patients, for instance post renal or liver transplant patients on long-term immunosuppression drugs.

Sebaceous gland carcinoma

SGC may masquerade as a recurrent chalazion or unilateral blepharitis in an elderly female patient. A large incisional biopsy is required for histopathologic analysis. This tumour can spread by lymphatics, and the patient requires radical neck excision. There is a significant 5-year mortality.

Malignant melanoma

Very rare but potentially very serious. Most pigmented lesions around the eye are benign, but the usual caveats apply—if there is an increase in size or if it bleeds, urgent referral is needed.

Common eyelid malpositions

As patients age, you will find that the eyelids change position; they become more lax and turn inwards (entropion) or outwards (ectropion) or droop (ptosis). Occasionally with disease, an eyelid can also turn in, turn out, droop or even open more due to retraction.

Aims

• Examine an eyelid.
• Identify entropion (lid in) and ectropion (lid out).
• Identify ptosis (lid down) and eyelid retraction (lid up).

Eyelid anatomy

It is important to understand the bilaminar structure of the eyelids, which have an anterior lamella and a posterior lamella.

Eyelid function

The eyelids are mobile and serve to protect the eye and distribute the tears. They also contain the oily glands (meibomian glands) which produce the oil for the tear film. When assessing eyelid malposition, you have to observe and make measurements.

Eyelid examination

• Measure visual acuity!
• Look at the whole face, eyebrow height and symmetry.
• Measure the vertical palpebral aperture (PA) and margin reflex distances (MRDs) and the amount of scleral show (SS) above or below the limbus in millimetres.
• Measure the levator function (LF) in millimetres—upper-lid excursion from full downgaze to full upgaze.
• Assess the orbicularis strength and Bell’s phenomenon (do the eyes roll upwards under upper eyelid on closure?).
• Exclude aberrant eyelid movements.
• Lag on downgaze—eyelid hangs up on downgaze.
• Detect lagophthalmos—eye remains partially open on attempted closure.
• Exclude distichiasis, trichiasis, entropion and ectropion.
• Examine tarsal conjunctiva and conjunctival fornices to exclude scar or tumour.

Eyelid malpositions

Entropion

In entropion, the eyelid turns in towards the cornea and the lashes touch the surface of the eye. Another cause of eyelashes touching the eye is distichiasis, where an aberrant row of eyelashes arises from the meibomian orifices with the eyelid margin in a normal position.

Aetiology

• Involutional—older persons.
• Spastic (causes by severe squeezing of the eyelids in response to ocular discomfort).
• Cicatricial entropion secondary to conjunctival scarring, such as staphylococcal lid margin disease (mild entropion), ocular cicatricial pemphigoid (severe entropion) or trachoma.

Pathogenesis

Thinning of the lamellae and disinsertion of the lower lid retractors.
The pre-septal overrides the pretarsal orbicularis, causing in-turning of the lower lid.

Symptoms

Ocular irritation, discomfort, reflex watering (hypersecretion), redness and occasionally keratitis if left untreated. It is worse when lying down (e.g. reading in bed).

Treatment

• Temporary treatment: lid taping and topical lubricants; botulinum toxin A injected into the pre-septal orbicularis alleviates symptoms for up to 4 months but has to be repeated.
• Surgery is the mainstay of treatment.
• Lateral tarsal strip with everting sutures (LTS + ES). This shortens the lower eyelid horizontally and everts the eyelid.
• Simple everting sutures (ES) alone.

Ectropion

In ectropion, the lower eyelid turns outwards away from the eye.

Aetiology

• Involutional—older persons.
• Cicatricial causes (e.g. post blepharoplasty, actinic, following skin tumour excision or from contact dermatitis).
• Mechanical—the weight of an eyelid tumour pulling the eyelid outwards.
• Facial palsy—paralytic (seventh cranial nerve (CN) palsy).

Symptoms

Watering, irritation, grittiness and redness.

Treatment

• Involutional ectropion—shorten the eyelid horizontally and turn the medial part inwards using a lateral tarsal strip and excision of a diamond shape of medial tarsal conjunctiva or medial spindle (LTS + MS).
• Cicatricial ectropion—skin graft or flap to lengthen the anterior lamella; horizontal shortening may also be required.
• Contact dermatitis—stop the causative eye drops or change to preservative-free drops. No surgery needed.
• For facial palsy.

Ptosis

Eyelid ptosis is abnormally low position of the upper eyelid margin.

Congenital paediatric ptosis

Aetiology

• Involutional or aponeurotic (thinning or dehiscence of the anterior part of the levator, the aponeurosis): good levator function (LF).
  Occurs commonly in the elderly and with contact lens wear.
• Myogenic: LF is very poor. Includes the congenital dystrophic (fatty) levator muscles in children and myopathies in adults (e.g. chronic progressive external ophthalmoplegia).
• Neurogenic: the LF is usually poor (e.g. third CN palsy).
• Mechanical: usually good LF (e.g. neurofibromatosis).
• Traumatic ptosis may be aponeurotic, myogenic or neurogenic.

Symptoms

• Cosmetically poor appearance
• Functional—reduces the visual field.

Management

Depends on the type of ptosis and LF.

• Normal or good LF is >10 mm, moderate LF is 5–10 mm and poor LF is <5 mm.
• Good and moderate LF: anterior levator resection (ALR)—tuck or advance the levator aponeurosis or muscle.
• Poor LF: frontalis suspension with autogenous fascia lata.

Eyelid retraction

Lower motor neurone facial palsy (seventh CN palsy) and thyroid eye disease can both cause exposure keratitis.

Lacrimation (tearing)

Watering eyes occur when there are too many tears or poor tear drainage.

Lacrimal anatomy and physiology

Lacrimal anatomy

The lacrimal drainage system consists of the punta, canaliculi, lacrimal sac and nasolacrimal duct (NLD).

Lacrimal physiology

The tears are produced by the lacrimal gland and the accessory lacrimal tissue (the glands of Krause and Wolfring) and are swept over the eye surface with each blink. Tear evaporation occurs (approximately 25%). The marginal tear strip drains via the lower canaliculus predominantly (70%) and 30% via the upper canaliculus. The lacrimal pump mechanism is the action of the eyelids contracting and pumping the tears into the lacrimal sac.

Aims

• Understanding the difference between hypersecretion and epiphora.
• Using syringing in assessment of epiphora.
• Dacryocystorhinostomy.
  Nasolacrimal duct obstruction is a common cause of epiphora (watering eye). Surgery to correct this is called dacryocystorhinostomy (DCR) in which an opening between the lacrimal sac and the nose is made.
  DCR is done via the nose (endonasal) or via the skin (external approach).

Watering eyes

There are many causes of a watering eye, and careful assessment is required.

• Hypersecretion: excess production of tears in response to stimulation of the trigeminal nerve from corneal irritation (e.g. a corneal foreign body), dry eye or conjunctival irritation (e.g. blepharitis or conjunctivitis).
• Epiphora: reduced tear drainage from lacrimal system obstruction at any point from the punctum, canaliculus, sac or nasolacrimal duct.
  Nasolacrimal duct obstruction is the commonest cause.
  The commonest cause of epiphora is a blocked nasolacrimal duct (NLD). This can be primary from chronic inflammation with subsequent fibrosis and stenosis, or, less commonly, secondary from sarcoidosis, Wegener’s granulomatosis, tumour or trauma.
  DCR is the treatment of choice.

Mucocoele

A mucocoele is a dilated lacrimal sac containing mucous. It is often seen as a lump at the medial canthus, and it is caused when the nasolacrimal duct distal to it is blocked.
Functional epiphora: epiphora in the presence of patent syringing without hypersecretion due to:

• eyelid malposition (e.g. lower lid ectropion)
• lacrimal pump failure (e.g. facial palsy)
• punctual, canalicular and nasolacrimal duct stenosis (without a complete obstruction).

Investigation of a watering eye

History

Stickiness or worse watering occurs outside or constantly. Often patient has a history of nasal disease, sinusitis, polyps or nasal trauma, previous conjunctivitis, eye drops and/or drugs.

Assessment of the watering eye

• External examination of the forehead and the periocular and medial canthus is performed to exclude eyelid malposition and mucocoele.
• Fluorescein dye retention test: watch a drop of fluorescein 2% rapidly disappear from the conjunctiva if the system is patent or show dye retention if it is blocked.
• Slit lamp examination can do the following:
  ○ Exclude blepharitis.
  ○ Exclude punctual stenosis.
  ○ Determine tear meniscus height.
• Probe and then syringe and irrigate the lacrimal system with saline.
• Nasal endoscopy
  ○ The nasal endoscope is used to look inside the nasal space to exclude nasal pathology such as tumours, inflammation and polyps as well as anatomical variations.
• Radiology imaging studies
  ○ Dacryocystography (DCG) with radio-opaque material for anatomical detail is used to determine the site of the
  obstruction.
  ○ Lacrimal scintigraphy is a nuclear scanning technique using a drop of technetium 99 placed in the conjunctival fornix and a gamma camera to observe its passive drainage.
  ○ It is used to detect physiological tear drainage in the assessment of functional NLD obstruction with partial obstruction.

Surgery

DCR can be external (via the skin) or endonasal (via the nose).

• Aim of DCR: create a functioning rhinostomy between the lacrimal sac and the nasal space.
• External (skin incision) approach.
• Endonasal DCR (via the nose) is less invasive (Figure 28.9). The rigid nasal endoscope provides good illumination and magnification transnasally. Many patients prefer endonasal DCR because it avoids a skin incision. Figure 28.10 shows a functioning DCR ostium in the nose.

Basic orbital assessment

The orbit is a space: the eye, eye muscles, fat, nerves, vessels and optic nerve are all enclosed on four sides by the bony orbit.
This chapter covers the anatomy of the orbit and the systematic approach to examining a patient with proptosis. The most common cause of proptosis in adult patients is thyroid eye disease, also known as Graves’ orbitopathy.

Aims

• Assessment of a patient with proptosis.
• Orbital imaging techniques.
• Differential diagnosis of proptosis.

Orbital anatomy

The bony orbit has four margins anterior and four walls. It lies adjacent to the ethmoid sinus (medial) and maxillary sinus (inferior). It contains the optic foramen for the optic nerve and ophthalmic artery, the superior orbital fissure (cranial nerves and blood vessels) and the inferior orbital fissure. The infraorbital nerve lies in the floor, partly in a bony canal. The orbit contains a lot of fat and connective tissue septae that support and cushion the eye and its muscles, optic nerve, nerves and blood vessels.

Orbital terms

• Proptosis: eye protrudes forwards out of orbit; also called exophthalmos.
• Enophthalmos: eye is sunken into orbit.
• Anophthalmia: socket contains no eye.
• Pseudophthalmia: socket contains an orbital implant.
• Microphthalmia: socket contains a very small eye or ocular remnant.
• Phthisical eye: a blind shrunken eye.

Loss of an eye

• Enucleation: removal of an eye in its entirety—detaching it from the optic nerve and the extraocular muscles.
• Evisceration: removal of the contents of the eye, leaving the outer sclera, the attached optic nerve and extraocular muscles.
• Post-enucleation socket syndrome: deep sunken ‘eye’ when the volume of the removed eye has not been adequately replaced.
• Prosthetic eye: artificial eye, usually made of acrylic.

Expansion of the orbital space

Orbital decompression is removing (usually) the medial and lateral orbital walls to expand the orbit in thyroid eye disease.

Orbital assessment

History

• Gradual or sudden onset. If slow and non-inflamed, it is more likely to be benign.
• Unilateral or bilateral.
• Orbital swelling, or sunken.
• Orbital pain.
• Periorbital redness (e.g. orbital cellulitis).
• Periorbital numbness.
• Visual disturbance.
• Double vision.
• Drooping eyelid.
• Systemic: malignancy or thyroid problem.
• Previous trauma.
• An ascultation for a bruit is a caroticocavernous fistula.

Clinical examination

Visual function (if eye is present) and eye examination

• Visual acuity and pupil reactions.
• Colour vision ± visual fields.
• Retina and optic disc.

Globe position

Measure proptosis with Hertel exophthalmometry (Figure 29.4)—is it axial or non-axial?

Measure proptosis or enophthalmos

Assess type of proptosis:

• Axial proptosis (anteroposterior protruding globe) without horizontal or vertical displacement. This suggests a generalized orbitopathy such as thyroid eye disease or an intraconal mass.
• Non-axial proptosis. Horizontal or vertical displacement of the globe is caused by a mass pushing it sideways. For instance, a lacrimal gland tumour in the superolateral quadrant pushes the globe inferomedially.
  Assess enophthalmos
• Is there a history of trauma and possible orbital floor fracture?
• Is there a phthisical eye?
• Is there an ocular prosthesis?
• Has the patient had an eye enucleated?
• Was there an orbital implant placed after enucleation or evisceration?
• Is there a secondary post-enucleation socket syndrome?
• Are the eye movements restricted? Is the socket lining contracted?

Check the cranial nerve (CN) function

• Third, fourth and sixth CN: extraocular muscle movement.
• Seventh CN: upper facial musculature.
• Fifth CN: corneal, periorbital and forehead sensation.

Feel the orbit

Palpate the orbital rim. If a mass is detected, is it separate from the rim? Describe its feel and shape, and draw a picture of its shape and location.

Complete the examination

Palpate the temporal fossa for extension of swelling. Exclude preauricular, submandibular and cervical lymphadenopathy. Examine the neck for thyroid enlargement or thyroid scar. Check sensation in the skin around the orbit.

Investigations

• Computed tomography scanning (Figure 29.5): axial and coronal views show the position of the optic nerve well, and also the sinuses and orbital walls (request bone window settings, too). Suspected vascular lesions need contrast.
• Magnetic resonance imaging: good for soft tissue but does not show bone as well.
• Orbital ultrasound: colour Doppler ultrasound to measure size and show blood flow and velocity within lesion.

Orbit disease, thyroid eye disease and facial palsy

Graves’ orbitopathy and facial palsy are common problems managed by the oculoplastic surgeon in conjunction with the endocrinologist, neurologist, neurosurgeon and plastic surgeon. The aim of the oculoplastic surgeon is to ensure that the patient maintains good vision, a comfortable eye and surgically rehabilitates.
Orbital tumours are a rare cause of proptosis.

Aims

• Manage Graves’ orbitopathy.
• Manage facial palsy.
• Differential diagnosis of orbital proptosis.

Common orbital problems

• Adult:
  ○ Graves’ orbitopathy (thyroid eye disease) (most common)
  ○ idiopathic orbital inflammation
  ○ cavernous haemangioma
  ○ lacrimal gland tumour
  ○ secondary tumours
  ○ nerve cell or sheath tumours.
• Child:
  ○ dermoid cyst
  ○ haemangioma
• ○ rhabdomyosarcoma
• ○ craniofacial abnormality.

Graves’ ophthalmopathy

This is also known as thyroid eye disease, dysthyroid eye disease, Graves’ orbitopathy and Von Below disease.
Patients with Graves’ ophthalmopathy usually develop their exophthalmos within 6–12 months of becoming hyperthyroid. Male patients and smokers have a more aggressive disease.
There is an active phase with inflammation which lasts up to 1 year (Figure 30.1a), and a subsequent inactive stable phase (Figure 30.2).
During the active phase there is increased fibrosis of the muscles and fat, contributing to the signs and symptoms of exophthalmos, eyelid retraction and restricted eye movement. The active phase is treated medically with immunosuppression (e.g. steroids and azathioprine).
Once the disease is inactive, surgery to the orbit, muscles and eyelids can be considered.

There is a varied presentation:

• Proptosis.
• Reduced colour vision from optic nerve compression.
• Restrictive strabismus with mainly inferior and/or medial rectus
  muscle enlargement causing diplopia.
• Eyelid retraction.
• Lagophthalmos.
• Exposure keratitis.
• Conjunctival redness and cheimosis.
• Periorbital swelling.
  The aim of treatment is to preserve vision, with eyes comfortable and looking normal, with full lid closure.

Orbital and lacrimal gland tumours

Orbital and lacrimal gland tumours cause proptosis and require incisional or excisional biopsy by a trained oculoplastics orbital surgeon.
Lymphoma and metastases are the commonest malignant tumours.
Many anterior and mid-orbital tumours can be biopsied via a skin approach. More posterior intraconal and lacrimal gland tumours (pleomorphic adenoma) may require excision via a lateral orbitotomy.

Facial palsy

This is caused by Bell’s palsy, herpes virus or posterior fossa tumour (sphenoidal meningioma).
The eye symptoms include:

• lagophthalmos (inability to close the eye fully)
• tearing
• red sore eye
• exposure keratitis
• reduced visual acuity
• brow ptosis
• upper eyelid ptosis
• lower eyelid paralytic ectropion
• cheek ptosis.
  Management is initially to preserve vision and keep the eye comfortable, and it is followed by surgical oculoplastic rehabilitation.

Treatment: Lubricant drops and ointment, punctual plugs, lower eyelid horizontal tightening, insertion upper eyelid gold weights, lower upper eyelid, cheek lift and hyaluronic acid gel cheek volumization.

Removal of an eye—enucleation and evisceration

Enucleation is done if there is severe ocular trauma which cannot be salvaged, for painful blind eye and for large intra-ocular tumour (e.g. malignant melanoma) where there is no other treatment option.
Evisceration is done if there is endophthalmitis and the walls of the eye can be preserved. The intraocular contents including the lens, vitreous, retina and choroid are removed as well as the cornea.
When an eye is removed by enucleation or its contents removed by evisceration, its volume must be replaced in order to avoid a sunken orbital appearance.
A buried spherical orbital implant (Figure 30.6) is inserted to which the rectus muscles are attached either directly or indirectly via a cover material. An ocular prosthesis (artificial eye) is then made to match the normal eye; usually it is acrylic and hand painted (Figure 30.5b).
If the volume of the enucleated or eviscerated eye is not replaced, the patient has a sunken socket appearance called post-enucleation socket syndrome and will need a secondary buried orbital implant.

Ocular oncology

Introduction

Neoplasia of the eye, although uncommon, can be devastating, as some tumours are not only sight threatening but also life threatening.
Ophthalmologists with an interest in ocular oncology manage cancers of the eye and adnexae. Benign and malignant tumours affect the eye, including naevus, melanoma, haemangioma, metastasis, retinoblastoma, lymphoma, astrocytoma, osteoma as well as others. Pattern recognition is important, as biopsy for diagnosis is performed rarely and in some cases, such as retinoblastoma, it is contraindicated due to risk of tumour seeding.

Choroidal naevus

The commonest fundus tumour is a benign naevus, which arises from melanocytes of the choroidal stroma; it is often discovered as an incidental finding and is rarely symptomatic. It is a flat or minimally elevated grey, dark or sometimes pale lesion (Figure 31.1). Overlying changes such as drusen or retinal pigment epithelial changes imply chronicity. Subretinal fluid, lipofuscin and growth raise the suspicion for malignancy (melanoma). Approximately 10% of the white population has a choroidal naevus, and the risk of malignant transformation is low.

Choroidal melanoma

The most common primary malignant tumour of the posterior uvea (choroid and ciliary body) is melanoma (Figure 31.2). Symptoms include blurred vision and flashing lights (photopsiae), depending on the size and location of the tumour, but they are frequently asymptomatic and found on routine check by an optometrist. Very large melanomas can present with a painful blind eye from neovascular glaucoma. Any retinal detachment should have a careful fundus check to rule out the presence of a tumour. The incidence of uveal melanoma is 6 cases per million people.
Examination reveals a dome-shaped or ‘collar stud’ mass which is located in the choroid (deep to the retina) and usually pigmented, but can occasionally be partly or entirely non-pigmented (amelanotic).
Retinal detachment and lipofuscin deposition are common features.
Management options include charged particle irradiation, plaque brachytherapy, local resection, enucleation, laser treatment or rarely observation. Deciding on which treatment modality should be employed depends on multiple factors including the tumour size, visual acuity of the affected eye and contralateral eye, age and general health of the patient and presence of metastases. Metastatic spread at the time of treatment is unusual, but systemic screening is advised for detection of liver involvement, even years after treatment of the ocular primary.

Retinoblastoma

Retinoblastoma is the most common intraocular malignancy of childhood, and its incidence is 1 in 15 000 live births. It can be unilateral or bilateral, and the overall mean age at diagnosis is 18 months. The most common and best known initial clinical sign is a white pupillary reflex, called leukocoria (Figure 31.3), but other presentations include a squint, raised intraocular pressure and orbital cellulitis. It is known to have one of the best cure rates (>95%) of all childhood cancers in the developed world.
There are two forms of the disease: a heritable (40%) and nonheritable form (60%). Also, two-thirds of the cases are unilateral, and the other third are bilateral. The retinoblastoma gene, Rb1 (chromosome 13), is a tumour suppressor, and both alleles need to have the mutation for retinoblastoma to manifest (Knudson’s double-hit hypothesis). If both mutations are in somatic cells, this is the nonheritable form and these cases are unifocal and unilateral. If one mutation occurs in a germ line cell, then one somatic mutation in a retinal progenitor cell results in usually multifocal, bilateral tumours that present earlier. These patients have a cancer syndrome, and once they survive retinoblastoma, they are prone to develop systemic cancers such as osteosarcoma and melanoma.
Retinoblastomas usually begin as small, transparent retinal tumours.
As they enlarge, they become white, opaque and calcified. Tumours can grow into the vitreous cavity (endophytic), under the retina (exophytic) or both. The management of retinoblastoma is complex.
Options include chemotherapy, cryotherapy, laser photocoagulation, thermotherapy and enucleation.

Vascular tumours

Vascular tumours include haemangiomas of the choroid or retina, they and are benign. Retinal capillary haemangiomas (Figure 31.4) are associated with von Hippel–Lindau syndrome. Choroidal haemangiomas that are circumscribed are non-syndromic (Figure 31.5), but diffuse ones are a feature of Sturge–Weber syndrome. Treatment modalities for haemangiomas are designed to reduce leakage and preserve vision, and these include laser photocoagulation, photodynamic therapy and external beam radiotherapy.

Ocular metastasis

Secondary deposits occur in the eye, particularly in the choroid due to its vascular nature. These present as yellow creamy subretinal deposits that grow rapidly, and in two-thirds of cases the primary site is already known. Staging investigations may reveal intracranial metastases. Treatment involves controlling the primary tumour site, and also local treatment to the eye with external beam radiotherapy or photodynamic therapy to try to preserve as much vision as possible.
The commonest primary sites are lung in men and breast in women.

Conjunctival squamous cell carcinoma (SCC)

SCC is the most common malignancy of the conjunctiva, and its incidence is about 1 to 2.8 per 100 000 people per year. Chronic sun exposure and immunosuppression are risk factors. Presentation is with red eye, pain, watering, burning and decreased vision. The appearance is of gelatinous, papillary, leukoplakic, diffuse or nodular lesions on the conjunctiva (Figure 31.6). Treatment is by excision and cryotherapy.
Adjuvant treatments include radiotherapy and topical chemotherapy agents.

Conjunctival melanoma

This arises most commonly from primary acquired conjunctival melanosis with cancer predisposing atypical cells, but it can arise from a naevus or de novo (Figure 31.7). Most cases occur in patients in their seventh decade, and they are managed with excision and cryotherapy.
Adjuvant treatments include radiotherapy and topical chemotherapy.
Distant metastasis can occur, and involvement of the orbit requires exenteration.

Conclusion

Ocular oncology is an important branch of ophthalmology as many of these patients have diseases that carry significant morbidity and mortality.
Pattern recognition of clinical signs that point towards malignancy is imperative.