Ocular Infection Consultations
Infections of the eye are caused by a variety of factors, many of which are treatable. It is important, however, to address emerging eye infections early in order to prevent permanent vision impairment and contagious spread of the disease. The ophthalmologists at Mass. Eye and Ear accept consult requests from other practices to assist in providing a thorough evaluation and diagnosis.
Click on the links below to learn more about common ocular infections:
The cornea can be damaged after a foreign object has penetrated the tissue, such as from a poke in the eye. At other times, bacteria, fungi, or parasites from a contaminated contact lens can pass into the cornea. Situations like these can cause painful inflammation and corneal infections called keratitis. These infections can reduce visual clarity, produce corneal discharges, and perhaps erode the cornea. Severe corneal infections can lead to corneal scarring, which can impair vision and may require a corneal transplant. For more information on corneal diagnoses and testing, please visit our Cornea Diagnostics page.
Ocular infections with the Herpes simplex virus (HSV, the cold sore virus) or Herpes zoster virus (HZV, the shingles or recurrent chicken pox virus) are the two most common causes of infectious corneal blindness in the industrialized world. It is important to seek qualified medical care as early as possible in the course of these diseases and to take measures to avoid transmitting the virus to others. Frequent and careful hand-washing, as well as avoidance of hand-eye contact, are the most important precautions.
HSV, the cold sore virus, usually presents with a red, somewhat painful and watery eye with blurred vision. The examining physician will discover characteristic sores on the surface of the eye, caused by live virus in the cornea, the round window at the front of the eye. Treatment consists of oral antiviral medication for about 10 to 14 days. Topical antiviral drops are also effective, but in less use because of the required dosage frequency and potential toxicity if used longer than three to four weeks.
Other forms of HSV are immune or inflammatory reactions deeper in the cornea. These may cause significant scarring despite the best of treatment. There may also be iritis (inflammation of the tissue behind the cornea that gives us our eye color). Therapy of all of these conditions includes steroid eye drops, with prophylactic antibiotic drops or ointment and oral antiviral to prevent a secondary corneal infection with bacteria or HSV.
HZV, or shingles, usually presents with moderate to severe pain in the eye and forehead region on one side. A few hours or days later, blisters appear in the area of pain. The eyeball, if involved, becomes red and may have corneal ulcers, immune disease in the deeper corneal tissues, and/or iritis, all similar to HSV. Treatment consists of antiviral medication daily for 7 days, at doses much higher than those used for HSV. Ocular treatment of inflammatory HZV disease is similar to that of HSV.
The pain of shingles can be severe, and in 9 percent of patients, it lasts a lifetime. Therefore, in addition to the treatment already mentioned, patients may be put on low doses of a tricyclic antidepressant (which also blocks pain transmission). Other pain medications may include anticonvulsants and certain oral or topical analgesics for the first few months.
Both ocular HSV and HZV are illnesses that can recur so patients should not delay seeing their ophthalmologist if they feel that something is going wrong again in one or both eyes. While there is no vaccine yet for HSV, there is a very effective vaccine for shingles, Zostavax™, which every adult should get from their primary care physician even if they have already had a case of shingles.
Viral infections of the eye are of particular clinical interest to Dr. Deborah Pavan-Langston of the Mass. Eye and Ear Cornea Service.
Toxoplasma gondii is a protozoan parasite that is present globally and causes a common infection in animals and humans. There are several strains of this parasite which can lead to substantial eye inflammation and repeat occurrences. Some strains stimulate the immune system, which leads to toxic levels of proteins. In turn, this results in extensive vasculitis and macular edema. Other strains cause significant retinal destruction because of the large amount of parasites present in the retina.
On-going research and treatment for these classes of disease are underway. We hope to further understand how to identify specific parasite strains and then develop targeted treatment for the virulence of the strains.
Ocular toxoplasmosis is of particular clinical and research interest to Dr. Lucy Young of the Mass. Eye and Ear Retina Service.