Pterygium :A pterygium is a benign proliferation of fibrovascular tissue covered by conjunctival-like epithelium extending onto the peripheral cornea.Pterygia are often preceded by pingueculae. Histopathologically, pterygia consists of subepithelial,fibrovascular tissue and elastotic degeneration of collagen. Pterygia can be located above or within Bowman's layer. A corneal epithelial iron line (Stockers line) can be seen in advance of the head of a pterygium on the cornea. The main risk factor for the development of pterygia appears to be exposure to ultraviolet light, because the prevalence of pterygia is positively correlated with proximity to the equator. Chronic environmental exposure to wind and dust might also play a role. Indications for surgical removal include reduced vision due to invasion of the visual axis or irregular astigmatism, unsatisfactory cosmetic appearance, and significant ocular irritation. A 15% to 50% recurrence rate has been reported following bare-sclera excision techniques. Postoperative therapy with beta- irradiation with Strontium 90, topical mitomycin-C drops, or conjunctival autografting have been recommended to decrease the risk of recurrence. 

Pyogenic Granuloma : This is a raised, fleshy, red, pedunculated lesion which can arise from the skin or conjunctiva. It is often accompanied by mucopurulent or purulent discharge. A pyogenic granuloma probably represents an exuberant healing process. Histopathologically, the lesion is composed of proliferating capillaries and fibroblasts without granulomatous inflammation. Pyogenic granulomas occur most often in association with inflammatory conditions, such as chalazia or chemical burns, or after conjunctival surgery, 9 such as pterygium excision. Pyogenic granulomas that do not resolve spontaneously may be excised or treated with topical corticosteroids. 

Phlyctenulosis : Phlyctenules (or phlyctens) are focal, translucent, lymphocytic nodules generally located at the limbus and usually accompanied by significant inflammation. Neutrophils enter the nodule a few days after onset as necrosis develops. Phlyctenules are believed to result from a delayed cell- mediated hypersensitivity reaction to staphylococcal antigens or to other exogenous sources. In developing countries, tuberculosis may be a significant cause. A conjunctival phlyctenule usually resolves without sequelae, although a limbal phlyctenule may result in localized fibrosis and vascularization of the peripheral cornea. A corneal phlyctenule can "wander" across the cornea, producing vascularization and scarring. Phlyctenules are generally responsive to low-dose topical corticosteroids, usually in combination with lid hygiene and topical antibiotic therapy. 

Conjunctival Viral Papilloma : Papillomas can occur on the eyelid margin, tarsal or bulbar conjunctiva, or limbus. They may have a pedunculated or sessile appearance. Pedunculated papillomas most often occur on the posterior eyelid margin, tarsal conjunctiva, or media] canthus of young patients. These lesions have been found to contain human papillorna virus (HPV) DNA that is characteristic of strains associated with non-malignant skin lesions, such as verruca vulgaris (cutaneous warts). If pedunculated papillomas are small, and if the patient has few symptoms, the lesions be observed, since they will often resolve spontaneously over months to years. If the patient is bothered by the lesions, options for management include cryotherapy, surgical excision, or intralesional alpha interferon injection. Minimal manipulation of the papilloma at the time of surgical excision is recommended to prevent dissemination of HPV to other conjunctival sites. Sessile lesions are more likely to occur in older patients and to be premalignant or malignant squamous tumors.