Abstract
Abstract: :
Purpose: To study the associated factors for development of hypotonous maculopathy (HM) in patients with ocular hypotony following glaucoma filtering surgery. Methods: Retrospective review of consecutive patients who presented with hypotony (intraocular pressure (IOP) < 6 mmHg, persisting for at least one month or presence of clinical signs of hypotonous maculopathy, independent of IOP level). Patients had previously undergone a filtration surgery (either trabeculectomy or combined trabeculectomy–phacoemulsification) with or without antimetabolite. Comprehensive patient information was recorded which included age, IOP, central corneal thickness (CCT), occurrence of hypotony and its management, as well as final outcome. Factors associated with maculopathy were investigated by univariate analysis and by a multivariate logistic regression analysis. Results: 15 eyes with HM and 25 hypotonous eyes without maculopathy were included. Among the predictable variables evaluated, a significant difference between the two groups was observed in the age of the patients; patients with maculopathy being significantly younger (55.9 ± 19.2 versus 72.4 ± 9.9 years; p = 0.004) and in CCT, with eyes that developed maculopathy having significantly thicker cornea (561.7 ± 48.0 versus 506.7 ± 32.0 µm; p = 0.001). Both groups had the same proportion of phaco–trabeculectomies with mitomycin C ( MMC) (40%) and trabeculectomies with or without MMC (60%). The IOP at the time maculopathy was diagnosed did not differ significantly from the IOP of hypotonous eyes without maculopathy (5.40 ± 3.58 and 4.16 ± 1.43 mm Hg, respectively, p = 0.412). Both predictive factors (younger age and thicker CCT) persisted as significant in the multivariate logistic regression analysis. Conclusions: Younger age has been previously identified as a risk factor for the development of hypotonous maculopathy. To the best of our knowledge, this is the first report of an association of thicker CCT and development of HM. This association might be the result of the influence of CCT on applanation tonometry, but we cannot rule out that thicker cornea might be a risk factor for maculopathy independently of its effect on the measurement of IOP. This study suggests that CCT should be considered when setting a target pressure after glaucoma filtering surgery, particularly if the target is very low.
Keywords: macula/fovea • intraocular pressure • clinical (human) or epidemiologic studies: outcomes/complications