Early post-phacoemulsification hypotony as a risk factor for intraocular contamination: in vivo model.

PURPOSE: To observe cataract wound dynamics and determine the risk for intraocular contamination under induced conditions of early postoperative hypotony after anterior chamber decompression for high intraocular pressure (IOP) spikes after uneventful phacoemulsification surgery.
SETTING: Department of Ophthalmology, Queen's Hospital, Burton-on-Trent, United Kingdom.
METHODS: In a prospective case series, 30 patients were treated with anterior chamber decompression for elevated IOP (>35 mm Hg) 1 to 2 hours after uneventful phacoemulsification through clear corneal temporal incisions. A drop of 2% fluorescein was instilled in the conjunctival sac before aqueous release to study the ocular fluid movements during and after the decompression procedure. The patterns of fluorescein movement were observed and photographed under cobalt blue light.
RESULTS: Fluorescein staining of the entire corneal tunnel was observed in all 30 eyes after decompression. An immediate fluorescein flare was observed in the anterior chamber after aqueous release in 24 eyes (80%) (P<.001). Observations over several seconds after decompression found a frank influx of fluorescein-stained fluid into the anterior chamber in 12 eyes (40%) (P<.001), giving rise to an "inverse Seidel's test." An intermittent ingress of fluorescein-stained fluid continued for several minutes after the procedure in 6 eyes (20%) (P<.05).
CONCLUSIONS: An incompetence of clear corneal cataract wound with intraocular contamination was observed during the period of induced hypotony after anterior chamber decompression in the early post-phacoemulsification period.