Clinical Pearls & Morning Reports
Published July 12, 2023
Amyloidosis can involve any tissue of the ocular adnexa, but such involvement is very uncommon. Read the NEJM Case Records of the Massachusetts General Hospital here.
Q: What is the most common cause of orbital inflammation?
A: The most common cause of orbital inflammation is thyroid eye disease. Eyelid edema and erythema, orbital resistance to retropulsion, limited extraocular motility, impaired levator-muscle function, and conjunctival chemosis and injection are consistent with thyroid eye disease. Eyelid retraction, lag, or flare are also typical findings of thyroid eye disease. Patients with thyroid eye disease occasionally present with ptosis, but it is uncommon. More than 20% of patients present with thyroid eye disease before systemic thyroid disease is diagnosed.
Q: Is metastatic cancer in the differential diagnosis for extraocular-muscle enlargement?
A: Metastatic cancer, lymphomatous or leukemic infiltration, or paraneoplastic disease can cause extraocular-muscle enlargement, at times with an inflammatory clinical appearance. Patients with these diseases may present with unilateral or bilateral limitation of extraocular motility, conjunctival chemosis and injection, resistance to retropulsion, or eyelid edema. Metastatic lesions that affect the extraocular muscles typically manifest as nodular or focal enlargement; in rare cases, lymphoma or leukemia manifests as bilateral, diffuse extraocular-muscle involvement. Extraocular-muscle enlargement can be the presenting sign of cancer.
A: Orbital sarcoidosis is an inflammatory process that can have slow progression with no pain. Sarcoidosis can cause bilateral extraocular-muscle enlargement, but in such cases, it would usually also cause lacrimal-gland enlargement or orbital masses. IgG4-related disease is another inflammatory process that can have orbital involvement with slow progression and minimal pain. Orbital IgG4-related disease most often results in lacrimal-gland enlargement and tends to cause enlargement of trigeminal nerve branches, particularly the infraorbital nerve, but extraocular-muscle enlargement can also occur. Orbital granulomatosis with polyangiitis usually causes lacrimal-gland enlargement or orbital masses, but isolated extraocular-muscle enlargement can occur occasionally.
A: Affected patients usually present to ophthalmologists with localized disease, most often with unilateral eyelid ptosis or an eyelid mass. Less than 10% of patients with ocular adnexal amyloidosis have systemic amyloidosis, with involvement of other organs. Only 2 to 16% of patients with ocular adnexal amyloidosis have extraocular-muscle involvement. Among such patients, those with bilateral, diffuse extraocular-muscle enlargement are more likely to have systemic amyloidosis than those with unilateral extraocular-muscle enlargement. Some patients with amyloidosis affecting the extraocular muscles can present with eyelid edema, and when there is extensive amyloid deposition in the ocular adnexa, the eyelids can take on an inflammatory appearance, with festoons and red discoloration of the skin.