OCULAR ALLERGIC DISEASES: DIFFERENTIAL DIAGNOSIS, EXAMINATION TECHNIQUES, AND TESTING

The eye is a common site for the development of allergic inflammatory disorders. Ophthalmologists and allergists frequently encounter allergic diseases of the eye in their general practice. Although the eye may be the only organ system involved in an allergic reaction, typically there also exists a systemic allergic component. Even so, ocular signs and symptoms often are the most prominent features of the entire allergic response. [1,2] The differential diagnoses of conditions presenting with a red eye include allergic disorders and a variety of other ocular abnormalities, some of which can produce profound visual loss if not treated appropriately. The signs and symptoms associated with these conditions often overlap, and it can be difficult to differentiate one ocular disease from another. Therefore, an understanding of ophthalmologic examination techniques and diagnostic procedures can help a health care provider make an accurate diagnosis of ocular allergy. This chapter provides a review of the various forms of allergic inflammation and focuses on the clinical characteristics that help to differentiate allergic disorders, both from each other and from other ocular conditions. The technique for the use of a direct ophthalmoscope in ocular examination is also outlined. Finally, various procedures and tests used to formulate the diagnosis and treatment of ocular allergy are discussed.