Dexamethasone Disodium Phosphate Penetration Into the Human Aqueous Humor After Topical Application.

PURPOSE: To study the amount of steroids that is found in the aqueous humor after topical administration of dexamethasone solution eye-drops and dexamethasone suspension eye-drops. MATERIALS AND METHODS: One hundred seventeen consecutive patients of both genders 18 years or older, candidates for cataract surgery were randomly assigned to one of three groups. Fifty-one patients (group A) received a single instillation of a suspension containing tobramicin 0.3% mg/ml + dexamethasone 0.1% mg/ml; 56 patients (group B) received a single instillation of a solution containing tobramicin 0.3% mg/ml + dexamethasone 0.1% mg/ml; 10 patients (group C), control group, did not receive any drops. Samples were taken immediately before surgery from the anterior chamber and dexamethasone levels were measured using gas chromatography/mass spectrometry. RESULTS: The mean dexamethasone concentrations were 0.56 µM (min 0.00, max 3.25) in group A and 0.15 µM (min 0.00, max 2.93) in group B. Dexamethasone was not detected in samples from group C. CONCLUSIONS: Dexamethasone suspension gives concentrations of steroids in the aqueous humor approximately three times higher than with dexamethasone solution drops.

Retinopathy during interferon-ß treatment for multiple sclerosis: case report and review of the literature.

The onset of new visual symptoms in patients with multiple sclerosis is often associated with a neuro-ophthalmologic manifestation of the disease. However, other possible differential diagnoses need to be ruled out, including drug-induced retinal side effects. Although uncommon, retinal side effects of interferon-beta formulations may occur, and need to be promptly recognized and treated by neurologists. In this manuscript, we report the case of a 37-year-old woman affected by multiple sclerosis diagnosed with interferon beta-associated retinopathy and we review the literature with regard to the epidemiology, clinical presentation, management and follow-up of interferon beta-associated retinopathy. Interferon-beta induced retinopathy seems to be an uncommon and a dose-related side effect in multiple sclerosis patients. Retinopathy tends to completely resolve after treatment discontinuation. Neurologists must be aware that immune-modulatory drugs, in particular interferon beta, have been reported to cause retinal side effects. In multiple sclerosis patients complaining of new visual symptoms during interferon-beta treatment, it is thus advisable to perform an ophthalmological assessment to rule out and properly manage retinopathy.