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Updated: Feb 10, 2026

Recurrent Herpetic Stromal Keratitis in Mice, a Model for Studying Human HSK
Published on: December 18, 2012
Queratitis Estromal en el Estudio de Enfermedades Oculares por Zóster (ZEDS): Lecciones Aprendidas
Deborah S Jacobs1, TingFang Lee2, Penny Asbell3
1Harvard Medical School, Boston MA.
Purpose:
To report on the presentation, treatment, and visual outcome of stromal keratitis (SK) in the Zoster Eye Disease Study (ZEDS).
Design:
Secondary analysis of SK endpoint of randomized clinical trial.
Subjects:
Herpes Zoster Ophthalmicus (HZO) patients were randomized in a double-masked clinical trial of oral valacyclovir 1g daily or placebo for 1 year. They were followed prospectively every 3 months for 18 months for endpoints of SK, iritis (IR), endothelial keratitis (EK), or dendritiform epithelial keratitis (DEK).
Methods:
Presentation of recurrent, new, or worsening SK was evaluated retrospectively by treatment assignment, randomization strata, and use of topical steroids. Investigators had been allowed discretionary treatment of endpoints including open label valacyclovir and topical steroids. Visual outcome and treatment with open label oral valacyclovir and topical steroids were evaluated.
Main Outcome Measures:
Use of open label valacyclovir and topical steroid treatment of recurrent, new, or worsening SK, and visual acuity at 12 months.
Results:
Recurrent, new, or worsening SK occurred in 105/527(20%) participants. Randomization group was not associated with this complication. Mean best corrected visual acuity at enrollment was logMAR 0.10±0.14 with no difference at 1 year, logMAR 0.13±0.2, and no difference between valacyclovir and placebo groups at enrollment or at 1 year. Among the 105 instances of SK, 79(75%) were recognized at scheduled study visits rather than at episodic visits. In only 11/105(10%) of recurrent, new, or worsening SK, did masked investigators opt to treat with open label oral antiviral. At the time of SK complication, 52/105(50%) were on topical steroid, but 47/52(90%) on topical steroids were using 1x daily or less, 21/47(45%) high potency and 26/47(55%) low potency (p=0.47). Of 48/105(47%) on no topical steroids at recurrent, new, or worsening SK, 18/48(38%) had discontinued steroids in the prior 3 months. 38/48(75%) on no topical steroids at complication SK were subsequently treated with high potency steroids 2x daily or more. Of 26/52(50%) on low potency steroids at complication SK, 23/26(88%) were treated with increase in frequency only.
Conclusions:
Individuals with ocular complications of HZO who develop SK generally maintain very good vision without use of oral antiviral therapy when monitored closely and SK is recognized and treated. Low potency topical steroids should be considered for treatment and ongoing suppression of SK in HZO.
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