Pathognomonlc feature of trachoma is
TRACHOMA Trachoma (previously known as Egyptian ophthalmia) is a chronic keratoconjunctivitis, primarily affecting the superficial epithelium of conjunctiva and cornea simultaneously. It is characterised by a mixed follicular and papillary response of conjunctival tissue. It is still one of the leading causes of preventable blindness in the world. Clinical Signs : A. Conjunctival signs : 1. Congestion of upper tarsal and forniceal conjunctiva. 2. Conjunctival follicles. Follicles look like boiled sagograins and are commonly seen on upper tarsal conjunctiva and fornix; but may also be present in the lower fornix. Follicles may be seen on the bulbar conjunctiva (pathognomic of trachoma). 3. Papillary hyperplasia: Papillae are reddish, flat topped raised areas which give red and velvety appearance to the tarsal conjunctiva. Each papilla consists of central core of numerous dilated blood vessels surrounded by lymphocytes and covered by hyperophic epithelium. 4. Conjunctival scarring: which may be irregular, star-shaped or linear. Linear scar present in the sulcus subtarsalis is called Arlt&;s line. 5. Concretions may be formed due to accumulation of dead epithelial cells and inspissated mucus in the depressions called glands of Henle. Corneal signs : 1. Superficial keratitis may be present in the upper pa. 2. Herbe follicles refer to typical follicles present in the limbal area. These are histologically similar to conjunctival follicles. 3. Pannus i.e., infiltration of the cornea associated with vascularization is seen in upper pat. The vessels are superficial and lie between epithelium and Bowman&;s membrane. 4. Corneal ulcer. 5. Herbe pits: are the oval or circular pitted scars, left after healing of Herbe follicles in the limbal area 6. Corneal opacity may be present in the upper pa. It may even extend down and involve the pupillary area. It is the end result of trachomatous corneal lesions. Image: Features of Trachoma Reference :- A K KHURANA; 6th edition, page:-62,64,65
Palpebral papillae
Bulbar papillae
Bulbar follicles
Palpebral follicles
Conjunctiva