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This may decrease the intraocular pressure by allowing the lens and iris to “sink” posteriorly, opening up the drainage angle. The Ophthalmologist may recommend an immediate dose of acetazolamide 500 mg, orally or IV, before a patient travels from a remote location.Management of keratitis, iritis and scleritisKeratitis can result from several aetiologies, including bacterial keratitis (most commonly secondary to contact lens use) or herpetic keratitis (see “Herpes simplex keratitis”). Key featuresHerpes simplex keratitis (dendritic ulcer)Reactivation of the herpes simplex type 1 virus (“cold sores”) can, in some people, result in ocular symptoms; the patient may not always be aware of a previous herpetic infection.Active herpes simplex keratitis is an inflammation of the corneal epithelium due to viral replication and infection causing characteristic dendritic corneal ulcers. Ulcers can be seen with fluorescein dye and appear as fine, branching (i.e. dendritic) lesions (Figure 4).6 Without the use of a slit lamp, these lesions can easily be confused with an abrasion (and vice versa).Subsequent complications can include an inflammatory response (without active viral replication) inside the middle layer of the cornea (stromal keratitis), or inside the eye (iritis/uveitis). There is usually no corneal epithelial defect, therefore fluorescein staining is not seen in these conditions, although the cornea is usually hazy in stromal keratitis.6Patients with suspected herpes simplex keratitis should be referred for ophthalmological assessment (or consider Optometrist triage if uncertain and the use of a slit lamp would assist in diagnosis). Ocular anti-viral treatment isare pain, photophobia and decreased vision. In severe cases, a level of purulent exudate within the anterior chamber may be seen (a hypopyon). Refer to an Ophthalmologist for treatment, which usually involves intensive topical antimicrobials.1Iritis (anterior uveitis) is often very painful due to ciliary muscle spasm. Key features also include photophobia and decreased vision, and the pupil will usually appear constricted with a poor light response and will sometimes be distorted due to adhesions. Ophthalmological assessment will confirm the diagnosis and exclude any possible infectious cause. Treatment (of non-infectious uveitis) involves topical, peri-ocular or systemic corticosteroids, as well as cycloplegics (dilating drops) to reduce pain and prevent adhesions in the eye.Scleritis (Figure 5) is characterised by severe, intense eye pain, described as deep, drilling pain, like a toothache.1

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