Macroscopic analysis with AS-OCT of filtering bleb in XEN gel stent

Session Details

Session Title: Glaucoma

Session Date/Time: Monday 09/10/2017 | 08:00-10:30

Paper Time: 10:06

Venue: Room 4.1

First Author: : L.Costa PORTUGAL

Co Author(s): :    J. Cardigos   S. Crisostomo   M. Sa Cardoso   I. Domingues   T. Gomes        

Abstract Details

Purpose:

The XEN Gel Stent is a Micro Invasive Glaucoma Surgery Device made of soft collagen and it is introduced by a corneal incision, trough the anterior chamber angle and it stands under the conjunctival space. The stent is introduced as single procedure or combined with phacoemulsification. To study the bleb morphology with AS-OCT and correlate it with the clinical evaluation. The authors have studied 27 eyes of 25 patients with the mean follow-up time of 10 (range 3 to 18) months after XEN Gel Stent implantation.

Setting:

The study was made in Centro Hospitalar de Lisboa Central.

Methods:

Two groups were characterized according to the clinical evaluation (Intraocular Pressure, topical treatment or additional procedures, as YAG-LASER and Needling). Group 1 describes those patients with IOP under 21 mmHg without topical treatment even if it was necessary an additional YAG-LASER or needling (n=20). Group 2 was formed with IOP above 21 mmHg or under 21mmHg with topical treatment (n=7). The parameters analyzed were the bleb structure (flattened, diffuse, cystic or mixed) and tube orientation in anterior chamber angle and distance to iris base.

Results:

Group 1 had 13 single and 7 combined procedures with postoperative mean IOP of 14,06 ± 2,49 mmHg. Group 2 had 5 single procedures with mean postoperative IOP of 19,71 ± 3,95 mmHg (p = 0,008). In group 1 the bleb was diffuse in 35%, cystic in 25%, 20% had mixed behavior. Group 2 had 100% of flattened blebs. The extension of filtering bleb is higher in group 1 than in group 2 (p<0.033). The distance of tube insertion to iris base was 0.287 ± 0,12 mm in group 1 and 0,086 ± 0,095 mm in group 2 (p< 0.002).

Conclusions:

In group 1 the bleb had 4 types of structural behavior: flattenes, diffuse, cystic or mixed behavior. In group 2 all patients had flattened blebs. The bleb functionality showed statistic importance with the distance of tube insertion to iris base and its relation with anterior chamber angle. Additional longitudinal studies about this topic will be necessary to improve the knowledge and the surgeon’s management capabilities.

Financial Disclosure:

NONE