One of the reasons I chose ophthalmology is that I am able to directly visualize the pathology — cataracts, macular edema, esotropia from a sixth nerve palsy, optic nerve edema.
Sometimes, however, the cause of pathology is not obvious. Being able to identify and diagnose these occult diseases may allow you to save your patient’s vision or life.
1. That’s not a stye?
Sebaceous carcinoma can mimic chalazia or styes. It can metastasize and sometimes needs to be treated with an orbital exenteration (removing the entire contents of the orbit!). You can discriminate a sebaceous carcinoma by looking for the yellow growth along the lid margins, flipping the eyelid and looking for spread to the palpebral conjunctiva and keeping a high index of suspicion in patients over the age of 50 with a “chalazion” that will not go away. Stage the cancer and treat with wide surgical excision and conjunctival map biopsy.
2. What’s going on back there?
Patients with painless vision loss over the past several weeks or months, including unabating photopsias and night blindness, can have cancer-associated retinopathy. Patients with melanoma-associated retinopathy can also acquire night blindness. These types of retinopathies are the result of autoantibodies to the eye from a nonocular cancer.
As an ophthalmologist, you can diagnose carcinomas, melanomas or recurrences of cancer and save a patient’s life. Work up with visual fields (central or cecocentral scotomas) and an electroretinogram (attenuated or absent photopic and scotopic response).
3. Can’t see 20/20, despite glasses?
Keratoconus can now be treated early with corneal cross-linking, potentially avoiding a penetrating keratoplasty (full thickness corneal transplant). Pay attention to those young adults who may frequently rub their eyes and who, despite best correction, you can’t get to 20/20. On retinoscopy (it’s not just for kids!) look for an oil droplet appearance from the conical shape of the cornea or scissoring of the red reflex (instead of the light coming back as a straight line, it reflects as a V-shape). In advanced keratoconus, you see can also see Munson’s sign: a V-shaped deformation of the lower lid when the eye is in downgaze.
4. Nevi, nevi, everywhere
Like your skin, your eye has pigment — especially in the uvea (choroid, ciliary body and iris). Melanocytes can get out of control and cause nevi or cancer. Always examine your patient’s iris and retina to look for these freckles or signs of melanoma. To distinguish between a choroidal nevus and a melanoma, Carol L. Shields, MD, has developed a mnemonic to help you: “To Find Small Ocular Melanoma Using Helpful Hints Daily.” Look for three or more of the following: Thickness > 2 mm, Fluid (subretinal), Symptoms, Orange pigment (presence of), Margin within 3 mm of the optic disc, Ultrasonographic Hollowness, absence of surrounding Halo, absence of Drusen.
5. What’s with all this swelling?
Nonspecific orbital inflammation (idiopathic orbital inflammation syndrome or IOIS) is a common diagnosis of exclusion marked by an edematous orbit. Disease can involve certain tissues — extraocular muscles, the lacrimal gland, anterior orbit, orbital apex — or be diffuse. Many patients improve with systemic steroid treatment. It’s important to rule out orbital lymphoma, sarcoidosis, primary tumors, metastases, infections and arteriovenous fistulas.
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Evan Silverstein, MD, is a pediatric ophthalmologist and an assistant professor of ophthalmology and associate resident program director at Virginia Commonwealth University in Richmond, Va.