"Shield ulcers" are seen in:

Ans. C. Vernal Keratoconjunctivitis. (Ref: Khurana 3rd Edition page 100.)Vernal corneal ulcers, also known as shield ulcers, are usually horizontally oval in orientation and involve the upper third of the cornea.Vernal Keratoconjunctivitis# Vernal keratitis is characterized by a combination of punctate epithelial erosions and keratitis. Punctate epithelial erosions are areas of absent epithelium that stain with fluorescein. Punctate epithelial keratitis is an influx of white cells into the corneal epithelium. The epithelium in this area stains with rose bengal, which stains devitalized cells.# Keratitis epithelialis of Tobgy is the early phase of vernal keratitis, consisting of minute white dots in the epithelium.# When the keratitis coalesces, a vernal (shield) ulcer is formed. There is often white material at the base of the ulcer, which has been reported to be mucopolysaccharides. In general, these ulcers are sterile, but there have been rare reports of superimposed infectious corneal ulcers occurring in VKC. These ulcers differ from vernal shield ulcers, which are indolent and often have a plaque at the base.# Horner-Trantas' dots are small white elevated lesions that appear at the apices of limbal excresences that consist of desquamated epithelial cells and eosinophils.# Subepithelial scarring and pseudogerontoxon also known to occur.Vernal conjunctivitis (Spring catarrh) : key facts- Bulbar and palpebral conjunctivitis- Bilateral and recurrent- Ropy discharge- 'Cobble stone' palpebral conjunctiva- Gaint papilla- Horner-Trantas spots- Maxwell-Lion sign- Pseudogerontoxon- Treatment with steroids, acetyl cysteine and topical NSAID