Since normal corneal tissue should be avascular (no blood vessel) and therefore clear to allow light to pass, the presence of blood vessel and the infiltration of cells as part of the inflammatory process results in scarring or hazing of the cornea. Diagnosis
A positive VDRL of Treponema pallidum immobilization test confirms diagnosis of luetic(syphilitic) interstitial keratitis

Treatment
The underlying cause must be treated as soon as possible to stop the disease process. Corticosteroid drop can be used to minimize the scarring on the cornea along with antibiotic cover. However, residual scarring cannot be avoided which can result in long term visual impairment and corneal transplantation is not suitable due to high rejection rate from the corneal vascularization. History
Previous long-standing eye infection which possibly during childhood time recalled as being treated with antibiotic and/or hospitalized over long period of time. == References ==
A topical spray consisting of an aerosol formulation of lidocaine and prilocaine was evaluated under the name PSD502 for use in treating premature ejaculation. The spray is applied on the penile skin prior to intercourse. While this formulation was not approved by the FDA, a similar product, Promescent, is available over-the-counter in the U.S. Dosage forms
Lidocaine/prilocaine eutectic mixture is marketed as a 5% oil-in-water emulsion incorporated in a cream base (EMLA cream) or  a cellulose disk (EMLA patch). The cream is applied under an occlusive dressing, while the patch incorporates an occlusive dressing to facilitate absorption of lidocaine and prilocaine into the area where anaesthesia is required. Local dermal anaesthesia is achieved after approximately 60 minutes, whereupon the occlusive dressing (or patch) is removed. The duration of anaesthesia is approximately two hours following removal of the occlusive dressing. E. Fougera & Co., makers of the generic cream widely used in the United States as Lidocaine and Prilocaine Cream, 2.5%/2.5%, recommends different timing for application of the cream as well as length of anesthesia. They state the cream must be applied at least one hour before the start of a routine procedure and for two hours before the start of a painful procedure. Additionally, they state that the duration of effective skin anesthesia will be at least one hour after removal of the occlusive dressing.