Granulomatous reaction to Bowman's layer in herpetic keratitis and band keratopathy

Abstract

Objective: To characterize granulomatous reactions around Bowman's layer.

Design: Case series.

Setting: Registry of Ophthalmic Pathology, Armed Forces Institute of Pathology, Washington.

Patients: All patients with a code for granulomatous reactions to Bowman's (membrane) layer or Descemet's membrane. In addition, all corneas identified as having elastotic or calcific degeneration of Bowman's layer were reexamined to identify a possible granulomatous reaction to Bowman's layer.

Results: Review of 210 corneal buttons and enucleated eyes yielded eight cases in which evidence of a granulomatous reaction to Bowman's layer was present: five patients with chronic keratitis, including three with herpetic keratitis (disciform in two and ulcerative in one), and three patients whose corneas had old degenerative pannus with calcification of Bowman's layer. In the patients with chronic keratitis the reaction tended to be focal and accompanied by inflammation; in those with degenerative pannus the reaction was diffuse and accompanied by minimal inflammation.

Conclusions: Granulomatous reactions to Bowman's layer are observed much less frequently than granulomatous reactions to Descemet's membrane. Although the pathogenesis of granulomatous reaction to Bowman's layer is unclear, a change in the antigenic properties of Bowman's layer may be implicated.