Examination of the sclera
- Discolorations : yellow= jaundice (e.g.marfans syndrome)
- Inflammation: episcleritis (circumscribed ) or deep + ciliary congestions indicated scleritis
- Staphylomas: bulging of uveal tissue at weak sclera
- Traumatic perforation : blunt trauma in limbus or equator
Scleritis Topic 30
Anatomy
- Forms posterior 4/5ths of the external fibrous tunic of the eyeball
- It is covered by the Tenons capsule
- In the anterior part also by the bulbar conjunctiva
- It inner surface lines the choroid &potential space= suprachoroidal space
- Near the limbus , it has a furrow which encloses the Schlemm’s canal
- Thickness varies with age; thickest posteriorly 1mm , thinnest anteriorly 0.3mm
- It is pierced in three locations posterior: optic nerve +short ciliary nerves & vessels
- Middle (posterior to equator ) 4 vortex veins aka vena verticosae
- Anterior (3-4mm from limbus)→ anterior ciliary vessels
- Microscopically of 3 layers : Episcleral tissue (outer )& sclera proper ; lamina fascia(inner)
Episcleral tissue → thin, dense, vascularised containing fibroblast, macrophages + lymphocytes
Sclera proper→ avascular consist of dense bundles of collages fives crossing in all directions
Lamina fascia→ blends with suprachoroidal & supraciliary laminae, contains pigmented→ brown