treatment plan
Finding Relief for a Light-Sensitive Patient
BY LEO SEMES, OD, FAAO
A 22-year-old white female complained of glare at ambient light levels. She had noticed this for most of her life and had become increasingly concerned that it may be significant.
The patient was taking no medications and denied all allergies. She had blond hair, blue eyes and fair skin. She did not report any history of ocular surgery or trauma. When asked specifically, she did not admit to photic sneeze response — sneezing in response to light, which practitioners sometimes encounter when examining patients at the slit lamp or with an ophthalmoscope. She reported no family history of eye diseases or surgery.
Finding the Cause
The patient's best corrected visual acuity was 20/20 in each eye with –1.00D sphere in each eye. The anterior segments of each eye were unremarkable for diseases and disorders. Specifically, the anterior chamber was clear, deep and quiet. She had a tear breakup time >10 seconds, normal blinking, appropriate lid apposition to the globe and normal lashes. Goldmann tonometry was 14mmHg in each eye.
The dilated fundus examination revealed a healthy optic nerve head, macular area with foveal reflex, intact retinal vasculature and the absence of predisposing conditions to retinal detachment. The vitreous was clear and attached. As you might expect, the fundus was lightly pigmented throughout except for the posterior pole, which showed typically increased macular pigment density.
The Diagnosis
This patient suffers from light sensitivity. A great deal of confusion surrounds appellations for photophobia.
In its strictest sense, photophobia occurs in patients with ocular inflammation who exhibit painful increased sensitivity at normal light levels. This has been explained as a reflex arc involving the edematous inflamed iris in patients who have anterior uveitis, for example. This patient's response was one of increased sensitivity but without pain. In addition, her anterior chamber did not manifest cells or flare.
Other types of glare are typically related to environmental situations. These may include disability and discomfort glare associated with stray light scattered within the eye and may be secondary to media opacities. Disability or discomfort glare also occurs in patients who have clear media as a result of unwanted reflections or above-threshold background brightness.
A Compound Treatment Option
For this patient, I suggested a 30-day regimen of 2mg zeaxanthin daily by mouth. Recently, a study of 40 patients demonstrated improved contrast sensitivity and decreased glare symptoms with increased macular pigment optical density (MPOD) measurements following daily dosing of lutein (6mg) and zeaxanthin (2mg). Both of these compounds can reach the macula when ingested orally, and their effect can be assayed using various clinical instruments specific to the task.
By the end of the dosing period, the patient reported subjective improvement in her glare symptoms.
MPOD measurements are being used to demonstrate a variety of effects, and this is one example of how nutritional supplementation can improve symptoms of discomfort glare. It's been shown that the effects of the zeaxanthin wear off when the supplementation is discontinued, so this patient will likely maintain the regimen to enjoy continued relief from glare. CLS
To obtain references for this article, please visit http://www.clspectrum.com/references.asp and click on document #158.
Dr. Semes is an associate professor at the University of Alabama at Birmingham School of Optometry.