Fig. 3.8 Characteristic rheumatoid joint disease with the ÒZÓ deformity of wrist and metacarpal joints

Fig. 3.9 Three vascular networks can be distinguished in the anterior segment of the eye: the conjunctival network, the superÞcial episcleral network, and the deep episcleral network

Fig. 3.10 Episcleritis. The edema is localized to the episcleral tissue; the superÞcial episcleral network is displaced forward because of underlying episcleral edema, and the deep episcleral network remains ßat

to distinguish the benign, self-limiting, and frequently symptomless episcleritis from the much more severe, destructive, and often painful scleritis, which can lead to loss of vision and portend serious systemic disease. Early diagnosis may lead to early treatment of the ocular and general condition. Differentiation between the two entities and further characterization of each can be accomplished if the eye is examined methodically and thoroughly, following a strict routine of examination.

3.1.7.1 Episcleral and Scleral Examination

Three vascular networks can be distinguished in the anterior segment of the eye: a conjunctival network, a superÞcial episcleral network, and a deep episcleral network (Fig. 3.9). In episcleritis, maximum congestion is in the superÞcial episcleral vascular network, with no changes in the deep episcleral network. The edema is localized to the episcleral tissue; the superÞcial episcleral network is displaced forward because of underlying episcleral edema, and the deep episcleral network

Fig. 3.11 Scleritis. The edema is localized to the scleral and episcleral tissue; the deep and superÞcial episcleral networks are displaced forward because of underlying scleral and episcleral edema

Fig. 3.12 External examination in daylight may show an obvious diffuse, grayish blue tinge of the eye with scleritis; the presence of brownish areas indicates a necrotizing process

remains undisturbed, thereby separating the two networks compared to the normal relationship (Fig. 3.10). In scleritis, maximum congestion is in the deep episcleral network, although there is also some congestion in the superÞcial episcleral network. The edema is localized to the scleral and episcleral tissue; the deep episcleral network is displaced forward because of underlying scleral edema and the superÞcial episcleral network is also displaced forward because of underlying episcleral and scleral edema (Fig. 3.11).

External Examination of the Eye in Daylight

External evaluation of the eye in daylight is sometimes helpful in distinguishing episcleritis from scleritis because tungsten and ßuorescent lights do not disclose subtle color differences. In episcleritis, the eye appears bright red. In deep scleritis, the eye has a diffuse, grayish blue tinge; this is because after several attacks of scleral inßammation, the sclera may become more translucent and sometimes thinner, allowing the dark uvea to show through (Fig. 3.2).

A dark brown or black-tinged area surrounded by active scleral inßammation indicates that a necrotic process is taking place (Fig. 3.12). If tissue

Fig. 3.13 Necrotizing scleritis. Note the dark area surrounded by active inßammation, characteristic of a necrotizing process

Fig. 3.14 Necrotizing scleritis. The sequestrum is partially removed