Abstract
Purpose: :
To describe the appearance, frequency, and clinical consequences of corneal endothelial involvement in human herpes simplex virus (HSV) keratitis as seen by in vivo confocal microscopy (IVCM).
Methods: :
We used slit-lamp examination and IVCM to study the eyes of 285 patients with HSV keratitis who visited the corneal department of the Rotterdam Eye Hospital between May 2005 and May 2008. The control groups comprised the unaffected fellow eyes of patients with HSV keratitis, the eyes of 58 healthy volunteers, and the affected eyes of 62 patients with inflammatory corneal disorders other than HSV. For IVCM, corneas were scanned either with Confoscan 3 or 4 (Nidek Technologies, Albignasego, Padova, Italy). All IVCM exams were qualitatively reviewed for signs of endothelial deviations characteristic of endotheliitis. Endothelial cell density (ECD) was evaluated on the first and last visits of patients who were followed for more than 100 days. The differences in ECDs were calculated and converted to percent ECD change per year.
Results: :
Endothelial alterations characteristic of endotheliitis were detected by IVCM in 107 eyes of 250 patients with HSV keratitis (43%). Neither the unaffected fellow eyes nor the eyes of healthy volunteers showed endothelial alterations. The endotheliitis-specific deviations consisted of pseudoguttata, enlarged intercellular gaps, infiltration of inflammatory cells into the endothelial layer, loss of defined cell boundaries, spot-like holes, and endothelial denudation. All of these signs disappeared with appropriate antiviral and anti-inflammatory treatment. However, the endothelium in eyes with endotheliitis-characteristic alterations showed significant decreases in ECD (10.3% per year) as compared to healthy fellow eyes. Similar endothelial alterations were detected in adenoviral, fungal, bacterial, and acanthamoeba keratitis. The same applied for non-infectious inflammatory corneal disorders.
Conclusions: :
IVCM allows earlier detection of endothelial alterations in patients with HSV keratitis than does slit-lamp examination. Although endotheliitis-specific alterations appear to resolve, the corneal endothelium can become irreversibly damaged. The endothelial deviations described herein are not specific for HSV keratitis. However, monitoring endothelial involvement and the consequent therapeutic adjustments might reduce the associated endothelial cell loss.
Keywords: herpes simplex virus • cornea: endothelium • imaging/image analysis: clinical