Ординатура / Офтальмология / Английские материалы / Fundamentals of Clinical Ophthalmology Cornea_Coster_2002

CORNEA

● Squamous cell carcinoma of the cornea

●

Terrien’s dystrophy

●

Squamous papilloma

●

Thygeson’s punctate keratitis

●

Superior limbic keratoconjunctivitis

●

Vernal keratoconjunctivitis

Indication for treatment

1.

Alter natural history of disease: eradicate infection

2.

Symptomatic: decrease pain

3.

Decrease disability: reduce blinding sequelae of inflammation

Preferred treatment

1.

Antiamoebic therapy: propamidine isothianate 0.1%

2.

Cycloplegia

Alternative treatment

Anti-amoebic therapy: polyhexamethylene biguanide 200 mg/ml

Complications of treatment

1.

Drug toxicity

2.

Hypersensitivity

Follow up

Daily until healed

Indication for treatment

1.

Symptomatic: relief of severe pain

2.

Alter natural history: achieve epithelial closure and prevent recurrence

Preferred treatment

1.

Dilate pupil to reduce spasm

2.

Pad

Alternative treatment

Bandage contact lens

Complications of treatment

–

Follow up

daily until healed

Indication for treatment

Symptomatic: to decrease pain and photophobia if severe

Preferred treatment

1.

Prednisolone phosphate 0.5% four times/day then titrate against level of

corneal inflammation.

2.

Only effective in controlling stromal inflammation. If the stroma is not

involved this approach will not help. There is no place for antiviral therapy

Alternative treatment

Withhold ocular medication

Complications of treatment

Ocular hypertension

Follow up

Every two weeks then on topical corticosteroids to monitor intraocular pressure

THERAPY OF CORNEAL DISORDERS

Allergic conjunctivitis

Indication for treatment

Symptomatic: to reduce inflammation

Preferred treatment

1.

Removal of the offending antigen (if known)

2. Topical corticosteroids (short term to relieve acute symptoms). Prednisolone

phosphate or

3. Topical mast cell stabiliser – as a prophylactic treatment, e.g. topical

lodexamide 0.1% or

4. Topical H1 receptor antagonist, e.g. levocabastine 0.05%

Alternative treatment

–

Complications of treatment

Long term topical steroids are associated with glaucoma

Follow up

Review regularly if on topical corticosteroids

Bacterial keratitis

Indication for treatment

1. Alter natural history of disease: eradicate infection

2. Symptomatic: decrease pain

3. Decrease disability: reduce blinding sequelae of inflammation

Preferred treatment

1. Antibiotics: cephalothin 50 mg/ml, gentamicin 14 mg/ml. Hourly for first

24 hours, then hourly during the day for three days then four times a day for

the next three days. Antibiotic choice modified following Gram stain, culture,

clinical course

2. Corticosteroids: prednisolone phosphate 0.5% 4/day after

organism identified and favourable response to antibiotics

Alternative treatment

Ciprofloxacin or ofloxacin as alternative to cephalothin or gentamicin

Complications of treatment

1.

Drug allergy

2.

Drug toxicity

Follow up

Daily until epithelium healed, then as required

Chemical injury to cornea

Indication for treatment

1. Symptomatic: to overcome pain

2. To improve natural history of disease by encouraging epithelial healing and

reducing corneal inflammation and lysis

Preferred treatment

Emergency lavage of conjunctiva

Pupil dilation – atropine 1% daily

Topical antibiotics if infection threatens

Topical corticosteroids (prednisolone phosphate 0.5%) if inflammation with

white cell recruitment ensues

Alternative treatment

Acetyl cysteine and ascorbic acid are currently being assessed in clinical trials

Amniotic membrane grafting is also being assessed

Complications of treatment

Toxicity. Excessive topical medication impairs wound healing, particularly

epithelial healing

Follow up

1. Severe burns should be hospitalised

2. Less severe cases need regular obsessive review, every 48–72 hours until

epithelium has healed, then as required

Indication for treatment

1.

Symptomatic: pain, photophobia

2.

Alter natural history: encourage epithelial healing

Preferred treatment

1.

Dilate pupil – homatropine 2%

2.

Pad

Alternative treatment

Prophylactic topical antibiotic, e.g. chloramphenicol 2/day until healed

Complications of treatment

Impeded epithelial healing, recurrent erosion, microbial keratitis

Follow up

Daily until healed

One week later and examine angle and posterior segment

Indication for treatment

1.

Symptomatic: pain

2.

Alter natural history: encourage epithelial healing

Preferred treatment

1.

Remove foreign body

2.

Prophylactic antibiotic, e.g. chloramphenicol twice daily until epithelium has

healed

3.

Cycloplegia – homatropine 2% at time of foreign body removal

Complications of treatment

Perforation, microbial keratitis, recurrent erosion

Follow up

Daily until epithelium has healed

Indication for treatment

To relieve the patient of symptoms of discomfort or redness

Preferred treatment

Topical steroids for 2–3 weeks

Alternative treatment

Mild cases – nothing

Severe cases – oral flurbiprofen 100 mg 3/day or oral indomethacin 25 mg

3/day

Complications of treatment

Gastritis secondary to non-steroidal anti-inflammatories

Follow up

May have recurrence and is seldom associated with a systemic disorder

Filamentary keratitis

Indication for treatment

To relieve pain

Preferred treatment

Depends on the underlying cause

1. Tear substitutes

2. Mucolytic agents – acetyl cysteine 10% twice daily

Follow up

As symptoms demand

THERAPY OF CORNEAL DISORDERS

Fungal keratitis – filamentous organism

Indication for treatment

1.

Alter natural history of disease: eradicate infection

2.

Symptomatic: decrease pain

3.

Decrease disability: reduce blinding sequelae of inflammation

Preferred treatment

1.

Natamycin 5% drops

2.

Miconazole 1% drops

Hourly for the first day

Hourly during the day for the second day

Then three hourly for the next five days

Then as required

Alternative treatment

Other imidazole, e.g. fluconazole, ketaconazole

Hourly for first day

Hourly during day for second day

Complications of treatment

1.

Sensitivity

2.

Toxicity

Follow up

Daily until healed

Indication for treatment

1. Alter natural history of disease: eradicate infection

2.

Symptomatic: decrease pain

3.

Decrease disability

Preferred treatment

1. Antifungal: flucytosine 1% drops, miconazole 1% drops

2.

Oral flucytosine 100 mg/kg/day

Drops hourly for first 24 hours

Hourly during the day for the second day

Then three hourly for the next five days

Then as required

Complications of treatment

1.

Sensitivity

2.

Toxicity

Follow up

Daily until healed

Indication for treatment

Symptomatic: cosmesis, discharge

Preferred treatment

Prednisolone phosphate 0.5% four times/day

Complications of treatment

Elevated intraocular pressure

Follow up

Weekly until lesion has disappeared

Indication for treatment

To alter natural history of disease by encouraging epithelial healing

Preferred treatment

Oc Acyclovir five times a day until epithelium healed, then 3/day for three days

Alternative treatment

1.

Other antivirals, e.g. triflurothymidine, idoxuridine

2.

Debridement plus antiviral

Complications of treatment

1.

Allergy

2.

Toxicity

Follow up

Review regularly while on therapy

Indication for treatment

To alter natural history of disease by encouraging epithelial healing

Preferred treatment

Oc Acyclovir 5/day until epithelium healed then 3/day for three days

Alternative treatment

Triflurothymidine 5/day until healed then 3/day for three days

Complications of treatment

1.

Allergy

2.

Toxicity

Follow up

Review regularly while on therapy

Indication for treatment

1.

Symptomatic: to reduce pain

2.

Decrease disability: improve vision

3.

Alter natural history: reduce scarring

Preferred treatment

Topical corticosteroids with antiviral cover. Commence prednisolone phosphate

0.5% 4/day and Oc acyclovir 3. Titrate steroid against inflammatory score.

Reduce Oc acyclovir to 2/day after one week then daily at the end of the

second week. Cease antiviral when steroid down to once a day administration

Alternative treatment

Nil

Complications of treatment

1.

Corneal ulceration: enhanced viral replication in epithelium

2.

Ocular hypertension

3.

Allergy

4.

Toxicity

Follow up

Initially every week

Later every 2–3 weeks

THERAPY OF CORNEAL DISORDERS

Herpetic uveitis

Indication for treatment

1.

Symptomatic: to reduce pain

2.

Decrease disability: to improve vision

3.

Alter natural history: reduce intraocular inflammation, reduce raised

intraocular pressure

Preferred treatment

Topical corticosteroids with antiviral cover. Prednisolone phosphate 0.5% and

Oc acyclovir to 2/day after one week then daily at the end of the second week.

Cease antiviral when steroid down to once a day administration

Alternative treatment

Nil available

Complications of treatment

1.

Corneal ulceration: enhanced viral replication in epithelium

2.

Ocular hypertension

3.

Allergy

4.

Toxicity

Follow up

Initially weekly reducing to every second or third week

Indication for treatment

1. Alter natural history of disease: eradicate infection

2. Decrease disability: reduce blinding sequelae of infection

Preferred treatment

Antibiotics: ciprafloxicin (3 mg/ml) or G. ofloxacin (3 mg/ml) 4/day

for weeks

Alternative treatment

G.penicillin (5000 U/ml) for nutrient variant streptococci

Complications of treatment

1.

Sensitivity

2.

Toxicity

Follow up

Frequent observation

Indication for treatment

To relieve symptoms of reduced vision and prevent further reduction in vision

Preferred treatment

1.

Topical corticosteroids

2.

Topical cycloplegics

3.

Treatment of the underlying aetiology (although often this has no beneficial

effect on the course of the interstitial keratitis)

Alternative treatment

Penetrating keratoplasty following treatment of the acute interstitial keratitis has

its limitations due to thin cornea, potential for recurrent iritis

Complications of treatment

Prolonged corticosteroid can result in the development of secondary cataract

and glaucoma

Follow up

1.

Residual corneal haze, scarring, thinning, astigmatism and calcification

remain following treatment

2.

Prolonged corticosteroids may result in secondary cataract and glaucoma

Indication for treatment

1.

Disability: to improve vision

2.

Symptomatic: decrease pain and photophobia

3.

Alter natural history of disease: to prevent visually damaging sequelae of

inflammation

Preferred treatment

1.

Anti-inflammatory: prednisolone phosphate 0.5% four times/day initially –

after three weeks titrated topical steroids against inflammatory score

2.

Antitreponemal therapy: systemic penicillin, if active disease identified

Alternative treatment

May need oral corticosteroids if scleral involvement

Complications of treatment

Elevated intraocular pressure

Follow up

Monthly until intraocular pressure confirmed to be normal on steroids then as

required

Indication for treatment

1.

Alter natural history of disease: to avoid invasive neoplasia

2.

Disability: to improve vision

Preferred treatment

Topical mitomycin C 0.02% four times/day or 5FU 1% in pulse doses

Alternative treatment

1.

Excision

2.

Excision and cryotherapy

Complications of treatment

1.

Limbal insufficiency

2.

Recurrence

Follow up

1. Weekly during treatment

2.

Six monthly for the first year

3.

Every year after this

Indication for treatment

Visual disability

Preferred treatment

1.

Spectacle correction

2.

Contact lens correction

3.

Corneal transplantation

Contact lenses are required when spectacles are not effective. Corneal

transplantation is reserved for those who cannot use contact lenses

Alternative treatment

Thermokeratoplasty in some cases

Complications of treatment

See Complications of Contact Lens Wear and Corneal Transplantation (p. 76)

THERAPY OF CORNEAL DISORDERS

Limbal dermoid

Indication for treatment

Symptomatic: cosmesis

Preferred treatment

Surgical excision and lamellar corneoscleral graft

Complications of treatment

1.

Infection

2.

Rejection

Follow up

1. End of week one

2.

End of week six

3.

End of three months

4.

End of six months

5.

End of nine months

6.

End of 12 months for suture removal

Metaherpetic ulceration

Indication for treatment

1. Symptomatic: to reduce pain

2.

Decrease disability: to improve vision

3.

Alter natural history: achieve epithelial closure

Preferred treatment

Treat stromal inflammation to improve epithelial healing. Topical corticosteroids

with antiviral cover. Commence prednisolone phosphate 0.5% and

Oc acyclovir 3. Titrate steroid against inflammatory score. Reduce Oc acyclovir

to 2/day after one week then to daily at the end of the second week. Cease

antiviral when steroid has been reduced to once a day administration

Alternative treatment

Contact lens

Complications of treatment

1. Ocular hypertension

2.

Allergy

3.

Toxicity, including impaired epithelial healing

Follow up

Weekly until epithelium healed

Indication for treatment

1.

Symptomatic: decrease discharge and discomfort

2.

Decrease disability: maintain vision through continued contact lens wear

Preferred treatment

1.

Improve lens care and cleaning

2.

Change to new lenses

3.

Decrease wearing time

4.

Suppress inflammation with prednisolone phosphate 0.1% four times daily

Alternative treatment

Mast cell stabiliser – disodium chromoglycolate four times a day

Complications of treatment

Elevated intraocular pressure

Follow up

Monthly when on steroids until sure that patient is not a steroid responder

Indication for treatment

1.

Symptomatic: cosmesis, discharge

2.

Confirm clinical diagnosis

Preferred treatment

Excisional biopsy

Complications of treatment

1.

Haemorrhage

2.

Infection

3.

Recurrence

Follow up

Weekly until healed

Indication for treatment

Visual disability

Preferred treatment

1.

Spectacles

2.

Contact lenses

3.

Corneal transplantation

Contact lenses are used when spectacle correction is inadequate. Corneal

transplantation is used when contact lens correction is inadequate

Alternative treatment

With extreme peripheral thinning an early peripheral lamellar graft may be

preferable to a penetrating corneal graft

Complications of treatment

See Complications of Contact Lens Wear and Implications of Corneal

Transplantation (pp. 76, 132)

Indication for treatment

Alter natural history: to prevent recurrences

Preferred treatment

Micropuncture

Alternative treatment

1.

Bandage contact lens

2.

Therapeutic photokeratectomy

Complications of treatment

1.

Recurrent erosion

2.

Infection

Follow up

Review as symptoms recur

Indication for treatment

Symptomatic: cosmesis

Preferred treatment

Excision: leave sclera bare

Complications of treatment

Infection

Follow up

Review until healed

Indication for treatment

Not indicated

Indication for treatment

1. Symptomatic: cosmesis

2.

Reduce disability: improve vision

Preferred treatment

Excision and conjunctival autograft

Alternative treatment

1.

Excision and flap repair

2.

Excision leaving sclera base

3.

Excision and irradiation

Complications of treatment

1.

Infection

2.

Recurrence

Follow up

Weekly until healed, then at six and 12 months

Indication for treatment

1.

To relieve symptoms of vernal keratoconjunctivitis

2.

To heal the ulcer

3.

Prevent secondary infective keratitis

Preferred treatment

1.

Treatment of vernal keratoconjunctivitis

2.

Scraping of the base of the ulcer combined with a bandage soft contact lens

3.

Treat the giant papillae (as already described)

Alternative treatment

1.

Superficial keratectomy or excimer laser may be required in recalcitrant cases

Complications of treatment

Iatrogenic corneal perforation

Follow up

The management is often difficult and prolonged. The shield ulcer may heal with

corneal scarring