Objective: The purpose of the study is to compare the efficacy and safety of transconjunctival needling and medical treatment in eyes with encapsulated blebs.
Design: A randomized, prospective study.
Participants: Two hundred eighty-two eyes that underwent a guarded filtration procedure between January 1994 and January 1996 at the Glaucoma Service of University of Campinas.
Intervention: Encapsulated blebs developed in 25 (8.9%) of 282 eyes and were randomized to either needling (n = 14) or medical treatment with aqueous humor suppressants (n = 11). If one treatment failed to maintain intraocular pressures (IOPs) below 20 mmHg, the other treatment was initiated. If both methods failed, surgical revision or further glaucoma surgery was performed. Complete success was defined as IOP less than 20 mmHg after one treatment method. Qualified success was defined when IOPs less than 20 mmHg were obtained with both treatment methods, whereas failure was defined when IOP greater than 20 mmHg or when further surgery was indicated.
Main outcome measures: Intraocular pressure, vision, and number of antiglaucoma medications.
Results: After a mean follow-up of 9.6 months, medical treatment alone was successful in ten patients (90.9%), whereas needling alone was successful in one patient (7.1%) (P = 0.00003). In the needling group, 92.9% of the eyes required aqueous humor suppressants, and 57.1% were considered qualified successes at the last follow-up (mean = 10.1 months). At the last follow-up examination, there was no statistically significant difference between the mean number of medications in both groups (P = 0.797). Further glaucoma surgery was performed in five patients (35.7%) undergoing needling and one patient (9.1%) receiving medical treatment (P = 0.162).
Conclusions: Medical treatment with digital pressure should be used as the initial treatment in eyes with encapsulated blebs. Needling procedures or surgical revision, methods that are more invasive and potentially associated with severe complications, should be limited to the small percentage of eyes that do not respond to medical treatment.