Pressure-Induced Interlamellar Stromal Keratitis After Laser In Situ Keratomileusis

Abstract

PISK appears clinically almost identical to diffuse lamellar keratitis after LASIK. It is important to measure the IOP and be suspicious when a diffuse interface haze occurs after the first postoperative week, is resistant to or even exacerbates in response to an increase in topical steroid treatment, and is not associated with other causative events. Slit-lamp optical coherence tomography is a valuable tool that allows differentiation between space-occupying interface fluid collection and non-space-occupying interface fluid collection to avoid falsely low or normal IOP measurements in PISK.

Delayed-onset interface fluid syndrome after laser in situ keratomileusis secondary to combined cataract and vitreoretinal surgery

“…It is often caused by a steroid-induced IOP increase and responds quickly to discontinuation of topical steroids and IOP-lowering medications. 8 However, it can also be caused by disorders resulting in compromise of the corneal endothelium and subsequent corneal edema, such as uveitis; preexisting endothelial cell dysfunction or decompensation, such as corneal endothelial dystrophy; or low endothelial cell count due to previous intraocular surgery. 6,8 In normal corneal structure, endothelial decompensation causes fluid transudation across the endothelium and subsequent microcystic edema due to the fluid collection in the basal epithelium.…”

“…8 However, it can also be caused by disorders resulting in compromise of the corneal endothelium and subsequent corneal edema, such as uveitis; preexisting endothelial cell dysfunction or decompensation, such as corneal endothelial dystrophy; or low endothelial cell count due to previous intraocular surgery. 6,8 In normal corneal structure, endothelial decompensation causes fluid transudation across the endothelium and subsequent microcystic edema due to the fluid collection in the basal epithelium. 8 However, the LASIK interface wound heals in a limited fashion and leaves a central and paracentral hypocellular primitive interface wound, creating potential space in the central stroma that requires less force to open than the tight junctions between corneal epithelial cells.…”

“…6,8 In normal corneal structure, endothelial decompensation causes fluid transudation across the endothelium and subsequent microcystic edema due to the fluid collection in the basal epithelium. 8 However, the LASIK interface wound heals in a limited fashion and leaves a central and paracentral hypocellular primitive interface wound, creating potential space in the central stroma that requires less force to open than the tight junctions between corneal epithelial cells. 6 In the post-LASIK cornea, fluid migration across the endothelium tends to collect in the potential space.…”

Laser in situ keratomileusis in 2012: a review

“…Pressure-induced interlamellar stromal keratitis has been described recently in peerreviewed literature. 8,119 This condition represents a case of interlamellar stromal keratitis induced by an acute steroid response and subsequent IOP rise following LASIK surgery. The condition appears to mimic diffuse lamellar keratitis in the time of onset following surgery and clinical signs.…”

Corneal Densitometry as a Tool to Measure Epithelial Ingrowth After Laser In Situ Keratomileusis

“…A more common complication that occurs at the interface is diffuse lamellar keratitis (DLK (Hamilton et al, 2002) and beginning anti-glaucoma medication (Tourtas et al, 2011) until the IOP goes down. If not treated appropriately, optic nerve damage and visual field loss can occur (Hamilton et al, 2002).…”