See Chapter 12.

Hemochromatosis

Systemic iron overload is not associated with corneal deposits or changes. In rare cases, congenital spherocytosis has been associated with deep intraepithelial reddish brown deposits in an oval shape of unknown pathogenesis. Iron depositions are discussed further in Chapter 12.

Corneal and External Disease Signs of Systemic Neoplasia

Chapter 8 discusses neoplastic disorders in greater depth. See also BCSC Section 7, Orbit, Eyelids, and Lacrimal System.

Enlarged Corneal Nerves

Several conditions feature enlarged corneal nerves. The most important of these conditions is multiple endocrine neoplasia (MEN) type 2B. This autosomal dominant (band 10q11.2) disease is characterized by medullary carcinoma of the thyroid gland, pheochromocytoma, and mucosal neuromas in patients who frequently have a marfanoid habitus. Besides the thickened corneal nerves, conjunctival and eyelid neuromas and keratoconjunctivitis sicca may occur. Patients with MEN type 2A also have been noted to have enlarged corneal nerves. Other causes of prominent corneal nerves from either true enlargement or increased visibility are listed in Table 11-5.

Table 11-5

Appendix

Skeletal/connective tissue disorders associated with corneal changes are summarized in the following table. For further discussion of some of the topics mentioned in the table, please see the appropriate sections in the chapter.

Table 11-6