and human immunodeficiency virus seropositivity [167, 170]. Necrotizing scleritis may occasionally be the initial manifestation of the invasive tumor [169].

8.4.3Dense Connective Tissue Tumors

8.4.3.1 Nodular Fasciitis

Nodular fasciitis is a benign nodular reactive proliferation of fibroblasts and vascular tissue within the fascias of the trunk, upper extremities, scalp, neck, and face, including the ones in the eye [171]. The lesion appears as a tender, isolated, vascularized, round or oval nodule with a size ranging from 0.5 to 1.5 cm in diameter; sometimes, the rapid growth suggest a malignant tumor, particularly a lymphoma or sarcoma, but excisional biopsy reveals proliferating fibroblasts varying in configuration from spindle to stellate. In the eye, the nodule may involve Tenon’s capsule, eyelid, periorbital tissue, and the ligaments of the extraocular muscles [172–174]. Episcleral nodules usually occur at the limbus or under the bulbar conjunctiva anterior to the insertion of the recti muscles. Episcleral tissue heals well after excision of the nodule and there are no recurrences.

8.4.3.2 Fibroma

Fibroma of the episclera may occur anywhere but usually arises adjacent to the limbus. They are vascularized, firm, of variable size, and not adherent to the sclera. Histologically, fibroma is a tumor composed by packed fibroblasts intermingled with inflammatory cells. If extracellular matrix components outnumber the fibroblasts, the tumor may be termed a myxoma. If extracellular matrix components and fibroblasts are present in similar amounts, the tumor may be termed a myxofibroma [118].

8.4.3.3 Fibrous Histiocytoma

Fibrous histiocytoma is a tumor composed of fibroblasts and histiocytes which arises from primitive mesenchymal cells with capacity to differentiate into either or both cell lines. The orbit is one of the most common locations of the tumor. Rarely, fibrous histiocytoma may originate in the

episclera and, although it usually remains localized, metastasis may occur. Excisional biopsy is essential for diagnosis and therapy. Histologically, there may be interweaving fascicles of fibroblasts (storiform pattern) and stellate deposits of dense collagen with fibroblasts intermingling with lipid-laden histiocytes [55]. Recurrences may occur after excision.

8.4.3.4 Sarcomas

Although primary sarcomas of the episclera and sclera are exceptionally rare [38, 175], secondary invasion from adjacent ocular structures occasionally may occur [176]. Rhabdomyosarcoma in a child has been reported to manifest as nodular episcleritis [38].

8.4.4Vascular Tumors

8.4.4.1 Hemangiomas

Episcleral capillary hemangioma occurs early in life, may grow rapidly, and often regresses before the child is 5 years old. Sometimes, however, the small and circumscribed tumor may be present for many years without any further growing, in which case it can be mistaken for nodular episcleritis; in the episcleral capillary hemangioma, the new vessels appear to radiate from the mass rather than skirt it, as in the inflammatory conditions [38]. Episcleral capillary hemangioma may be the only external manifestation of Sturge– Weber syndrome, which usually presents with facial (port-wine stain, nevus flammeus) and leptomeningeal angiomas. Because of its small size, it usually does not require to be removed.

Episcleral cavernous hemangiomas are often a peripheral manifestation of an orbital cavernous hemangioma. They present as a mass of vessels associated with an overlying conjunctival overgrowth which may bleed spontaneously and severely. Both episclera and conjunctiva are readily moveable over the underlying sclera. They are present at birth, grow rapidly, and often regress before the child is 5 years old. Conservative therapy is advised unless it is cosmetically intolerable, in which case, surgical removal is the proper treatment.