Visual acuity prognosis after anterior chamber air replacement to prevent pseudo-anterior chamber formation after deep lamellar keratoplasty

To investigate the prognosis of patients who received anterior chamber air replacement after deep lamellar keratoplasty (DLKP) during the study period, January 1995 to April 2000. The records were studied of 47 patients (54 eyes) (60.6 +/- 21.3 years of age) who underwent DLKP at Dokkyo University Hospital. Visual acuity and endothelial cell loss were assessed in patients (1) with and without Descemet's membrane perforation; (2) with and without the use of anterior chamber air replacement, and for different durations of air replacement; and (3) in the presence or absence of a pseudo-anterior chamber, and in relation to its duration if present. No significant differences in relation to the above three items were found in endothelial cell loss in study years 1 to 5. Average best visual acuity was 0.61 in perforated eyes, 0.54 in unperforated eyes, 0.54 in eyes that received air replacement, and 0.57 in eyes that did not. The average best visual acuity was 0.38 in eyes with a pseudo-anterior chamber and 0.68 in eyes without one. There was a significant correlation between the duration of the pseudo-anterior chamber and loss of visual acuity. The prolongation of a pseudo-anterior chamber eventually impairs visual acuity, whereas anterior chamber air replacement, used to prevent the development of a pseudo-anterior chamber, causes minimal endothelial cell damage. Anterior chamber air replacement, therefore, is an effective technique by which to prevent the development of a pseudo-anterior chamber.