Purpose
The aim of this study was to evaluate the relationship between filtering bleb
parameters (height, extent) and the wideness of the aqueous drainage route
beneath the scleral flap using ultrasound biomicroscopy (UBM) in patients who
have undergone trabeculectomy with and without mitomycin-C (MMC).
Design
This was a prospective interventional observation uncontrolled study.
Patients and methods
A total of 30 patients undergoing 30 glaucomafiltering surgeries were assessed for at
least 6 months using UBM to evaluate the bleb reflectivity, the visibility of the route
under the scleral flap, the bleb height, and the extent in correlation with the mean
intraocular pressure. Patientswere divided into two groups: groupA included 15 eyes
inwhichtrabeculectomywas performedwithoutMMCand groupBincluded15eyes in
which trabeculectomy was performed with MMC (0.4%) applied for 2 min.
Results
The reflectivity inside the filtering bleb showed a significant correlation with the
maximal width of the aqueous drainage route and the maximal height and the extent
of the bleb. Furthermore, the bleb function was significantly associated with its UBM
image in eyes trabeculectomized with adjunctive MMC.
Conclusion
The study concluded that the internal structure of the bleb can be a more sensitive
predictor of the outcome of filtering surgery.