Objective documentation of anterior chamber depth following trabeculectomy and its correlation with intraocular pressure and bleb functionality

The purpose of this study was to objectively evaluate the anterior chamber depth (ACD) after trabeculectomy and to correlate its variations with the intraocular pressure (IOP) and bleb functionality. Fifty eyes (46 patients) were included in this prospective study. ACD was documented with the use of a non-contact optical device (IOL Master-Carl Zeiss Meditec) and IOP was measured with the Goldmann applanation tonometer. Ophthalmological examination, IOP, and ACD measurements were performed before surgery, the day after and weekly thereafter. Linear regression Analysis between the 2 variables was performed and correlation coefficients were estimated. A 2-tailed t test was used and a P value < .05 was considered as statistically significant. Correlation coefficients between ACD and IOP, during the follow-up period, resulted in a moderate to strong positive relationship (r = 0.2–0.7), which since the 1st week resulted statistically significant at 5%. Twenty seven eyes (54%) needed at least 1 needling procedure. Considering each group separately, until the 3rd post-op week, the correlation coefficients in the needling group resulted higher than those in the non-needling group. Furthermore, in the needling group, the relationship between ACD and IOP, for the 1st, 2nd, 3(rd), and 4th week was statistically significant at 5%. The objective documentation of the ACD in the early post-trabeculectomy period presents a moderate to strong positive correlation with the IOP. Furthermore, the brisk deepening of the ACD during the first 2 to 4 post-operative weeks is strongly correlated with the increase of the IOP and early signs of bleb encapsulation.