Abstract
Purpose :
Patients who underwent Xen 45 surgery frequently require needling or revision surgery. To compare intraocular pressure (IOP), glaucoma medication (GM), complications and reinterventions of XEN implantation, filtering bleb needling (FBN) and open filtering bleb revision (OFBR).
Methods :
This is a retrospective, observational study of 269 eyes who underwent Xen surgery. Following groups were formed for data evaluation: 1) Primary Xen surgery until last follow up (FU), 2) Primary Xen surgery until first needling/revision/surgery (NRS), 3) FBN until next NRS, 4) OFBR until next NRS. Main outcome measures were IOP, number of GM, NRS and complications.
Results :
IOP in Group 1 was lowered from 23.3 (±8.3) mmHg to 15.6 (±6.3) mmHg, number of GM was reduced from 3.1 (±1.0) to 1.1 (±1.3) after a mean FU of 9.4 (±7.2) months. Group 2: IOP 23.3 (±8.3) mmHg to 18.1 (±8.5) mmHg, GM 3.1(±1.0) to 1.4 (±1.4) after a mean FU of 6.9 (±6.0) months. Group 3: IOP 23.7 (±7.6) mmHg to 18.3 (±7.3) mmHg, GM 2.0 (±1.4) to 1.8 (±1.3) after a mean FU of 6.7 (±6.5) months. Group 4: IOP 21.6 (±6.3) mmHg to 16.4 (±6.3) mmHg, GM 2.4 (±1.1) to 1.0 (±1.4) after a mean FU of 6.0 (±4.2) months. IOP and number of GM over time are shown in Figure 1 and 2. FBN and OFBR procedure was performed in 47 (17.5%) and 71 (26.4%) eyes after a mean interval of 3.1 (±4.3) and 7.9 (±5.0) months. An additional intervention was required less frequently in group 4 (8.5%) compared to group 2 (36.4%, p<0.001) and group 3 (42.6%, p<0.001) while no significant difference was observed between Group 2 and Group 3 (Chi-Square-Test). IOP reduction and IOP at last FU was not significantly different between all groups (Anova Tukey Post-hoc-test). GM at last FU was significantly lower in Group 4 compared to Group 3 (p=0.006) and Group 2 (p=0.025) (Wilcoxon-Mann-Whitney U-Test, p values with Shaffer correction). Ocular hypotony, anterior chamber reduction and choroidal effusion all occurred significantly (p<0.05) less often in group 3 (6.4%, 0.0%, 0,0%) and group 4 (15.5%, 1,4%, 1,4%) compared to group 2 (28.3%, 9.7%, 14.1%) (Chi-Square).
Conclusions :
Xen surgery is a safe and effective IOP and GM lowering method in glaucoma patients. A better safety, fewer secondary interventions and a tendency towards better IOP control was found for open filtering bleb revision as compared to primary XEN implantation and needling.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.