Bleb appearance after XEN surgery seems to be different to classic trabeculectomy literature. The present data suggest correlation of IOP and surgical long-term success with bleb morphology in AS-OCT. Prevalence of small diffuse cysts is directly associated with lower IOPs, while cystic encapsulation at 3 months predicts higher surgical failure.

Purpose: The outer stent lumen can be located either deeper (in or under Tenon's layer) or more superficially in the conjunctival stroma after the transscleral XEN Glaucoma Gel Microstent (XEN-GGM; Allergan Plc., USA) implantation. The present study aimed to investigate the effect of the postoperative conjunctival implant position on surgical success and intraocular pressure (IOP) after XEN-GGM. Methods: Prospective data from 66 consecutive open-angle glaucoma eyes of 54 patients were collected preoperatively and 1 and 2 weeks, and 1, 6 and 12 months postoperatively. The layer of implantation was determined in the first month postoperatively as intra-and subtenon or intraconjunctival depending on the location of the outer lumen of the stent in OCT (Visante OCT; Zeiss, Germany). Primary outcome measures were differences in relative IOP reduction at 12 months between the two groups. Further, complete and qualified surgical success, number of secondary needlings and number of IOP-lowering medications and absolute IOP were assessed. Results: Relative IOP reduction was higher in intra-and subtenon group (n = 37/ 66, 56%) at week 1 (À54% versus À19%, p < 0.001), week 2 (À39% versus À21%, p = 0.02), month 1 (À42% versus À28%, p = 0.035) and month 12 (À39% versus À24%, p = 0.024). The mean absolute IOP was lower in intra-and subtenon group at week 1 (10.8 [95%CI,.0] mmHg, p < 0.001) and months 12 (13.9 [95%CI,] mmHg, p = 0.041). At month 6, a lower burden for IOP-lowering medication was shown for the intra-and subtenon group (0.2 AE 0.5 versus 1.0 AE 1.1, p = 0.034). The mean number of secondary needlings, which were done in 47/66 (71%) of the eyes, was lower in the intra-and subtenon group in the first year (1.9 AE 1.7 versus 1.2 AE 1.2, p = 0.03). Qualified surgical success was higher in the intra-and subtenon group (90% versus 61%, p = 0.01) after 1 year. Conclusion: The present study demonstrates a higher efficacy achieved with lower secondary needling rates in deeper implant positions in conjunctiva after XEN-GGM.

No author has a financial or proprietary interest in any material or method mentioned.

Although the HSM-IOL showed decreased flare 1 day postoperatively, no statistically significant differences regarding PCO were found 1 year postoperatively.

No author has a financial or proprietary interest in any material or method mentioned.