Punctate keratopathy

Adverse reactions may include mild, transient burning or stinging upon instillation palpebral edema superficial punctate keratopathy epithelial keratopathy ... 

The most frequent adverse reactions to trifluridine administration are transient burning or stinging and palpebral edema. Other adverse reactions include superficial punctate keratopathy, epithelial keratopathy, hypersensitivity, stromal edema, irritation, keratitis sicca, hyperemia, and increased intraocular pressure. 

In some patients, especially those over age 50 years, a localized or diffuse desquamation of corneal epithelium becomes evident (figure 6-3). This epithelial reaction usually consists of superficial punctate keratitis and probably results from exposure and tear film instability associated with decreased reflex tearing, infrequent blinking, and increased tear evaporation. The punctate keratopathy is frequently absent immediately after anesthetic instillation but may appear 5 to 30 minutes later (Figure 6-4). 

Goldstein MH, Eeistmann JA, Bhatti MT. PRK-pTK as a treatment for a patient with Thygeson s superficial punctate keratopathy CLAOJ 2002 28 172-173-... 

Watson SL, Hollingsworth J, TuUo AB. Confocal microscopy of Thygeson s superficial punctate keratopathy. Cornea 2003 22 294-299. 

Corneal involvement, in the form of superficial punctate keratopathy of the epithelium, is common and is found in 100% of patients. More serious changes include corneal ulceration, with subsequent loss of vision in 70% of patients, neovascularization, pannus, and scarring. Other corneal findings include Trantas dots, keratoconus, and filamentary keratitis. 

HSV = herpes simplex virus NSAIDs = nonsteroidal anti-inflammatory drugs SPK = superficial punctate keratopathy. 

Adverse reactions are remarkably few. The ophthalmic ointment causes a mild transient stinging sensation and a diffuse superficial punctate keratopathy which clears when the drug is stopped. Oral or i.v. use may cause gastrointestinal symptoms, headache and neuropsychiatric reactions. Extravasation with i.v. use causes severe local inflammation. 

All ophthalmic medications are potentially absorbed into the systemic circulation (Figure 63-3), so undesirable systemic side effects may occur, as well as potential local toxic effects due to hypersensitivity reactions or to direct toxic effects on the cornea, conjunctiva, periocular skin, and nasal mucosa. Eyedrops and contact lens solutions commonly contain preservatives such as ben-zalkonium chloride, chlorobutanol, and chelating agents for their antimicrobial effectiveness. In particular, benzalkonium chloride may cause a punctate keratopathy or toxic ulcerative keratopathy. 

Because of controversy regarding the specificity and sensitivity of the conjunctival changes, some investigators have based the clinical assessment of the prevalence of xerophthalmia only on the appearance of corneal signs. From the preceding discussion, it is obvious that except for a punctate keratopathy, corneal involvement is a late manifestation and would far under assess the prevalence of hypovitaminosis A, and even of xerophthalmia. 

Ophthalmic - Latanoprost-associated ocular adverse events reported at an incidence of 5% to 15% included the following Blurred vision, burning and stinging, conjunctival hyperemia, foreign body sensation, itching, increased pigmentation of the iris, punctate epithelial keratopathy. 

If NaFl stain is instilled for a TBUT measurement, it is a natural extension to then look for corneal and/or conjunctival staining. The presence of NaFl staining, rather than representing a true stain, indicates epithelial disruption, because the NaFl pools in areas of intercellular defects. Typically, the distribution of dry eye-related punctate epithelial keratopathy is in the lower third of the cornea and/or conjunctiva. 

Examination typically reveals diffuse SPK erosions and also may disclose punctate epithelial keratopathy that is visible as small grayish opacities in the epithelium. The location and pattern of this keratitis can be helpful in determining the etiology (Box 26-1) and in distinguishing the condition from bacterial-related causes. SPK from blepharitis usually is more severe in the inferior one-third of the cornea where it contacts the staphylococcal exotoxins from infection of the lower lid. In cases of SPK caused by bacterial conjunctivitis, the entire cornea may be involved. 

Recurrent HSK has accompanying lid and conjunctival involvement in about 31% of cases. This involvement typically appears as unilateral follicular conjunctivitis with moderate to severe diffuse conjunctival hyperemia. The initial epithelial lesions of HSK are small vesicles that are generally described as punctate epithelial keratopathy. Although dendritic or ameboid keratitis is the most common manifestation of HSK (Figure 26-47), a diffuse... 

The differential diagnoses of TSPK include viral, toxic, bacterial, chlamydial, exposure, and dry eye causes of punctate epithelial keratopathy. Most of these conditions resolve in shorter time periods and are found to have a more obvious conjunctival involvement. Considering the lack of laboratory confirmatory tests, the diagnosis of TSPK remains solely clinical. 

The corneal response in VKC occurs with varying levels of severity. The changes initially begin with punctate epithelial keratopathy, which may be serious enough to cause a decrease in vision to 20/200, with associated photophobia. Corneal epithelial macroerosion or areas... 

Local apphcation of 3% ophthalmic ointment can cause mild transient stinging. Diffuse, superficial, punctate, non-progressive keratopathy can develop. This quickly resolves after withdrawal (12,13). 

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