Chapter 7
The Conjunctiva
Introduction
The conjunctiva is a thin, transparent mucous membrane lining the upper and lower lids and covering the globe up to the limbus.
Areas of the conjunctiva
There are three areas to the conjunctiva:
•Palpebral conjunctiva – lines the upper and lower lids.
•Bulbar conjunctiva – reflects back to cover the sclera up to the limbus.
•Fornices – the upper and lower fornices are blind sacs, formed where the bulbar and palpebral conjunctiva fold back over each other.
Layers of the conjunctiva
The epithelial layer contains the goblet cells; the stromal layer contains the blood vessels, nerves and the glands of Krause and Wolfring (in upper only).
The conjunctiva is connected to Tenon’s Capsule around the limbus. Elsewhere it is loosely attached, especially in the fornices where there are folds of the conjunctiva. This allows for easy mobility of the eyeball.
Functions of the conjunctiva
•Allows easy movement of the eyeball.
•Goblet cells provide mucin for the tear film.
•It is a protective layer to the eyeball by being a physical barrier and by its rich blood supply.
Blood supply
There is a rich blood supply, especially in the fornices, delivered and drained via:
•anterior ciliary artery and vein
•superior and inferior medial palpebral artery and vein
•conjunctival artery and vein.
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Nerve supply
The nerve supply to the conjunctiva is by the long ciliary branch of the nasociliary nerve from the trigeminal nerve.
Lymphatic drainage
Lymphatic drainage is through the pre-auricular, parotid and submaxillary nodes.
Conditions of the conjunctiva
Conjunctivitis
Conjunctivitis is inflammation of the conjunctiva, which has several causes:
•bacterial
•viral
•allergic
•chlamydial
•fungal
•parasitic
•associated with other diseases
•other ophthalmic conditions
•mechanical.
Bacterial conjunctivitis
Bacterial conjunctivitis can be either acute or chronic.
Causative organisms
•Streptococcus.
•Staphylococcus aureus.
•Pneumococcus.
•Gonococcus.
•Haemolytic Streptococcus.
Signs
Typically there is conjunctival injection, especially in the fornices where the blood supply is rich (Fig. 7.1). The eye may, on the other hand, be white or only mildly red. Discharge is variable, but typically is present in the mornings, and on waking the eye is difficult to open because the eyelids are stuck together. This is a very important point when taking a history from a patient with suspected conjunctivitis. The eyelids may be red and inflamed. The condition may be unilateral or bilateral. The vision is always unaffected and
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Fig. 7.1 Bacterial conjunctivitis. (Reproduced with permission from Khaw, P.T. & Elkington, A.R. (1985) Disorders of the external eye, The Practitioner, 229, 317.)
there is usually no pain. The patient may complain of a gritty or foreign body sensation, some discomfort and very occasionally very mild photophobia.
Nursing action
•Check the patient’s visual acuity.
•Swabs are only necessary if there is any doubt of the diagnosis or if the condition has not resolved.
•Obtain an accurate history from patient to determine a correct diagnosis.
•Examination of the eye on slit lamp to confirm diagnosis
•Clean the eye(s) and instruct the patient on cleaning it (them), using cooled, boiled water.
•Give verbal and written instruction on how to instil the eye drops. This is usually Chloramphenicol drops, which may be prescribed four times a day for a period of 7–10 days. In severe cases, Chloramphenicol drops may be prescribed every two hours for two days and then four times a day for 7–10 days. If warranted, an ointment can also be prescribed for night-time application. In order to reduce the risk of complication arising from the use of chloramphenicol drops, it is advisable to check for any family/history of blood disorder since there have been reported cases of aplastic anaemia (Field, Martin & Witchell, 1999). Caution should also be exercised in women who are pregnant. If in doubt, Fucidic Acid (Fucithalmic) can be prescribed instead. In children, it is wise to prescribe Fucidic Acid as this only necessitates a twice-daily drop regime.
•Instruct patient on how to prevent the spread of infection either to his other eye or to other members of the household:
Wash hands before and after instilling eye medications.
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Use separate face flannels and towels in the home, as this is the usual method of spread of infection. Change face flannels and towels daily.
Use clean tissues rather than handkerchief to reduce the spread of infection.
Change pillowcases daily.
•Keep Chloramphenicol drops in a cool place, preferably in a fridge.
•Never share drops and ointment with anyone else.
•It is important that patients are reminded to finish all the prescribed course of treatment.
•Warn him not to wear a pad over the eye, as it provides a suitable environment for a further bacterial growth.
•If eye make-up is used, advise the patient to discard and buy new cosmetics when infection has cleared up.
Ophthalmia neonatorum
Severe conjunctivitis occurring in a baby less than 28 days old is a notifiable disease. This may be caused by Gonococcus, Streptococcus, or Chlamydia which is the most common cause. However, this condition needs to be distinguished from the neonatal conjunctivitis caused by nasolacrimal obstruction with other bacterial infection, trauma and inclusion conjunctivitis agents.
Signs
•severe discharge
•red, swollen eyelids (Fig. 7.2)
•chemosis
•unilateral or bilateral infection.
Fig. 7.2 Ophthalmia neonatorum.
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Nursing action
•The condition must be clearly and sensitively explained to both parents (or carers). They should be told of the baby’s diagnosis and the likelihood of how the baby has the infection.
•Both parents must be screened and examined at the genito-urinary medicine clinic.
•Clean/instruct the parent to instil the prescribed antibiotics.
•Topical Tetracycline is the treatment of choice.
•This condition can be associated with Otitis media and gastrointestinal tract infections so oral antibiotics are usually prescribed.
Complications of chronic conjunctivitis
•conjunctival scarring
•chronic blepharitis due to upset in the tear film
•conjunctival ulceration leading to perforation due to decreased conjunctival nutrition
•marginal corneal ulcer.
Viral conjunctivitis
Causes
•Adenovirus
•Measles
•Varicella
•Herpes simplex (see p. 108)
•Chlamydia.
Signs
•red/pink eye (Fig. 7.3)
•chemosis, if severe
•follicles may be present on the palpebral conjunctiva
•cornea – superficial punctate keratitis
•enlarged pre-auricular nodes, which may be tender
•bleeding from conjunctival vessels in severe adenoviral conjunctivitis.
Patient’s needs
•Relief of symptoms:
watering eye
irritation, which may be present
photophobia
generally unwell feeling.
•Instruction on treatment.
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Fig. 7.3 Adenoviral conjunctivitis. (Reproduced with permission from Khaw, P.T. & Elkington, A.R.(1985) Disorders of the external eye, The Practitioner, 229, 317.)
Nursing action
•Treatment is mainly supportive and educative since there is no effective treatment for adenovirus conjunctivitis.
•Usually no treatment is given as viral infections are self-limiting, running a course of 7–10 days.
•Artificial lubricant can be prescribed for patient comfort.
•Full explanation of the condition to increase patient awareness and reduce discomfort.
•General advice for hygiene is the same as for bacterial conjunctivitis.
•Thorough cleaning of slit lamps using HAZ or Milton solutions.
•If prisms are used during the examination, where possible, use disposable tonoshield or tonosafe. If these are unavailable, then the prism must be wiped clean while moist before the face of the lens is immersed in the disinfection fluid normally used. At the end of each clinic session, the prisms should be cleaned with detergent, rinsed thoroughly in sterile saline and then wiped dry (RCO guidelines, 2002).
•Vigilant hand washing by all medical and nursing personnel.
•If photophobia is present, advise patient to wear dark glasses.
Allergic conjunctivitis
Causes
• hay fever – tends to be seasonal.
Signs
•severe chemosis
•red eye
•papillae may be present on the palpebral conjunctiva.
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Symptoms
•irritation of the eye
•watering eye
•nasal signs of hay fever may be present.
Treatment
•antihistamines such as Xylometazoline Hydrochloride (Otrivine Antisin) drops four times a day or
•G. Sodium Cromoglycate (Opticron) 2% four times a day
•steroids, if condition is severe.
Vernal conjunctivitis or spring catarrh
A common seasonal, warm-weather condition, some patients being affected annually in the spring or early summer (see Fig. 7.4). It usually affects the 10–14 years age group, boys more than girls.
Signs
•giant papillae on subtarsal conjunctiva, called ‘cobblestones’ (see Colour Plate 1)
•corneal punctate epithelial erosions.
Symptoms
• irritation, foreign body sensation in the eye.
Treatment
•G. Sodium Cromoglycate 2%; steroids, if severe
•test for allergy and avoid cause, if possible.
Fig. 7.4 spring catarrh.
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Eczema
Signs
•redness of eye
•red, dry, scaly eyelid
•skin around eye may be affected
•slight discharge may be present
•fine papillae on palpebral conjunctiva.
Symptoms
•burning sensation
•photophobia.
Treatment
•antibiotic drops to prevent secondary infection
•steroid cream, e.g. betamethasone or sodium phosphate or hydrocortisone to eyelid and affected skin around the eye.
Chlamydia trachomatis/adult inclusion conjunctivitis
Chlamydia or adult inclusion conjunctivitis is caused by serotypes D to K. It typically affects young adults, with eye symptoms appearing a week after sexual activity. It is important to obtain an accurate history from patient and this should include duration of eye problems, any systemic symptoms, any known sexual contact and any treatment for sexually transmitted disease.
Signs
•red eye
•discharge
•follicles and papillae on palpebral conjunctiva
•chemosis of bulbar conjunctiva
•small tender pre-auricular nodes
•keratitis
•pannus formation on upper portion of the cornea; this is the development of new blood vessels growing into the cornea and is usually a later sign of the disease.
Patient’s needs
•Relief of symptoms, pain, photophobia, watering eye.
•Instruction on treatment.
Nursing action
•Take swab for testing for Chlamydia ensuring sufficient material is obtained (see p. 27).
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•Instruct the patient on the treatment:
Oc. chlortetracycline 1% four times a day for six weeks
oral tetracycline 250 mg four times a day for six weeks
sulphonamides may also be given.
•Sensitivity and tact must be shown to the patients and their partners when informing them of the diagnosis.
•Importance of treating the partners even though they maybe asymptomatic.
•Appointment must be made for them to attend the genito-urinary medicine clinic
Trachoma
Trachoma also known as Egyptian ophthalmia or granular conjunctivitis is caused by an organism called Chlamydia trachomatis which is a parasite closely related to bacteria. Trachoma is caused by serotypes A, Ba, C. It is common in hot, dry climates where there is a low standard of hygiene and flies are abundant. The disease runs a long and chronic course. The incubation period is 5–14 days. In a child, the onset is insidious, but it is acute in an adult.
Signs and symptoms
•oedematous eyelids
•discharge
•pain
•follicles especially on upper lid
•photophobia
•repeated attacks leading to entropion and corneal involvement
•long term – corneal scarring leading to severe loss of vision and blindness.
Treatment
•Early stages – antibiotic treatment of tetracyclines, erythromycin or sulphonamides for four to six weeks.
Complications
•Conjunctival scarring and fibrosis resulting in:
blockage to the drainage of the accessory tear glands and lacrimal gland resulting in a reduced tear film
reduction in secretion of mucin.
Both these results will cause a reduction in lysozyme in the tear film and therefore the patient will be prone to chronic conjunctivitis
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blocked lacrimal ducts from conjunctival scarring, which could cause dacryocystitis
entropion and trichiasis
ptosis, due to scarring under the top lid.
•Scarring of the cornea due to pannus formation, trichiasis and scarred palpebral conjunctiva.
Treatment of the complications
•Scarred conjunctival tissue can be treated by expressing and curetting the follicles. Plastic surgery may be necessary to correct lid deformities.
•Corneal graft to replace the scarred cornea. This can only be performed once the lid deformities have been corrected so that they will not abrade the grafted cornea.
•Administration of replacement teardrops to treat the dry eyes.
•Use of antibiotic drops for chronic bacterial conjunctivitis.
•Antibiotic treatment for dacryocystitis.
•A dacryocystorhinostomy to correct the blocked nasolacrimal ducts.
Fungal conjunctivitis
Fungal conjunctivitis is caused by Candida albicans. Babies can be affected during birth through an infected birth canal. Fine white plaques are apparent on the conjunctiva. Affected adults have blepharitis.
The treatment is with nystatin drops and ointment.
Parasitic conjunctivitis
In hot climates, parasites causing onchoceriasis (river blindness) and schistosomiasis (bilharzia) can induce conjunctivitis.
Conjunctivitis caused by other diseases
General diseases which cause conjunctivitis are:
•skin diseases: psoriasis, pemphygoid, acne rosacea and pemphigus
•Sjögren’s syndrome (p. 88)
•thyroid disease
•Reiter’s syndrome.
Ophthalmic conditions causing conjunctivitis
•dacryocystitis
•canaliculitis
•dry eyes.
The treatment is that of the general disease or ophthalmic condition.
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Mechanical conjunctivitis
Conjunctivitis can occur after the conjunctiva has been exposed to:
•wind
•fumes
•smoke
•dust
•dirt particles
•chemicals.
Subconjunctival haemorrhage
Subconjunctival haemorrhage occurs as a result of blunt or penetrating injury (see Chapter 14) but it can also occur spontaneously or as a result of a sudden increase in pressure in the eye, as occurs with violent sneezing or heavy lifting. The subconjunctival blood vessels burst, with the affected area varying in size; in severe cases the haemorrhage can cover the whole of the sclera causing swelling but usually sparing the superior aspect as it pools inferiorly from gravity. In cases occurring spontaneously, the patients usually have few symptoms apart from a dull ache. It is a condition that looks more severe than it is. It can be a sign of hypertension, vascular disease or a blood clotting disorder.
Patient’s needs
• Location of the cause, if any, of spontaneous haemorrhage.
Nursing action
•Ask the patient if he had exerted any undue pressure before the haemorrhage occurred, e.g. by heavy digging in the garden, sneezing fit, rubbing the eye.
•Take the blood pressure; if abnormal, inform the doctor.
•Reassure the patient that the haemorrhage will not cover the cornea.
•Inform him that it may spread further before it begins to resolve and that it may take two to three weeks to clear completely, similar to a bruise. Usually there is no specific treatment.
•Check if patients are on Aspirin, Warfarin or any other relevant medication.
•Advise patient to see GP for advice such as INR check if appropriate.
•If sub-conjunctival haemorrhage is as a result of trauma, the eye has to be carefully examined under the slit lamp for any other injuries.
Pterygium
A pterygium is a triangular-shaped nodule in the conjunctiva (Fig. 7.5), usually occurring on the nasal side, but it can be temporal. It usually occurs
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Fig. 7.5 Pterygium.
in people who live in hot, dry climates or who work in the open air. It is a degenerative process and can encroach on the cornea. If it affects the vision, it can be removed under local anaesthetic. Beta rays or cytotoxic eyedrops can be given following removal to prevent recurrence.
Pinguecula
A pinguecula is a yellow, triangular nodule found in the conjunctiva of the elderly and in people who work in exposed conditions. It affects the nasal side and later the temporal side. It does not spread to the cornea and no treatment is necessary unless it becomes inflamed, when steroid drops will reduce the condition. It can be removed for cosmetic reasons.
Concretions
Concretions are white deposits found in the conjunctiva. They are fairly common and are usually symptomless. Occasionally they are large enough to give a foreign-body sensation, when they can be removed under local anaesthetic (see p. 51). If bleeding occurs during this procedure, a pad and bandage should be applied.
Conjunctival cysts
Cysts can occur in the conjunctiva. If they cause symptoms, they are easily punctured under local anaesthetic (see p. 51). This can be a recurrent condition.