Papillae

Papillae are vascular changes seen most easily in the palpebral conjunctiva where fibrous septa anchor the conjunctiva to the tarsus. With progression, these dilated vessels sprout spokelike capillaries that become surrounded by edema and a mixed inflammatory cell infiltrate, producing raised elevations under the conjunctival epithelium (Fig 3-1).

A mild papillary reaction produces a smooth, velvety appearance (Fig 3-2A). Chronic or progressive changes result in enlarged vascular tufts that obscure the underlying blood vessels (Fig 3-2B). Connective tissue septa restrict inflammatory changes to the fibrovascular core, producing the appearance of elevated, polygonal, hyperemic mounds. Each papilla has a central red dot that represents a dilated capillary viewed end-on. Examination of the palpebral, bulbar, and forniceal conjunctivae beyond the tarsus is less helpful in revealing the nature of an inflammatory reaction, because the anchoring septa become sparser toward the fornix and permit undulation of less adherent tissue. With prolonged, recurrent, or severe conjunctival inflammation, the anchoring fibers of the tarsal conjunctiva stretch and weaken, leading to confluent papillary hypertrophy. Giant papillae are defined as those with a diameter greater than 0.3 mm (Fig 3-2C). The furrows between these enlarged fibrovascular structures collect mucus and purulent material. After treatment, a fibrotic subepithelial scar may be seen at the apex of the former giant papilla.

Table 3-2 Conjunctival Signs

Figure 3-1 Cross-sectional diagram of a conjunctival papilla with a central vascular tuft surrounded by acute and chronic leukocytes.

Figure 3-2 Papillary conjunctivitis. A, Mild papillae. B, Moderate papillae. C, Marked (giant) papillae.

Follicles

Conjunctival lymphoid tissue is normally present within the substantia propria except in neonates, who do not have visible follicles. Conjunctival follicles are round or oval clusters of lymphocytes (Fig 3-3). Small follicles are often visible in the normal lower fornix. Clusters of enlarged, noninflamed follicles are occasionally seen in the forniceal or inferior palpebral conjunctiva of children and adolescents, a condition known as benign lymphoid folliculosis (Fig 3-4).

Follicular conjunctivitis is characterized by conjunctival injection and the presence of new or enlarged follicles (Fig 3-5). Vessels surround and encroach on the raised surface of follicles but are not prominently visible within the follicle. Follicles can be seen in the inferior and superior tarsal conjunctiva and, less often, on the bulbar or limbal conjunctiva. They must be differentiated from cysts produced by tubular epithelial infoldings during chronic inflammation and lymphangiectasis.

Figure 3-3 Cross-sectional diagram of a conjunctival follicle with mononuclear cells obscuring conjunctival blood vessels.

Figure 3-4 Benign lymphoid folliculosis.

(Courtesy of Kirk R. Wilhelmus, MD.)

Figure 3-5 Follicular conjunctivitis. A, Inflammation of the right eye from glaucoma medication. B, Right eye showing follicular conjunctivitis in the inferior fornix.

(Courtesy of John E. Sutphin, MD.)

See also BCSC Section 4, Ophthalmic Pathology and Intraocular Tumors.

Stern G. Chronic conjunctivitis, Parts 1–2. Focal Points: Clinical Modules for Ophthalmologists. San Francisco: American Academy of Ophthalmology; 2012, modules 11–12.

Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.