Preserflo Microshunt Implantation With Or Without Subconjunctival Injection Of Ophthalmic Viscosurgical Device

To explore whether subconjunctival injection of OVD at the end of a Preserflo microshunt implantation and suturing the distal end of the stent can improve the IOP lowering success rate of the operation.

Retrospective interventional single center single surgeon study.

The study involved 47 eyes of 36 glaucoma patients who underwent Preserflo microshunt implantation. Group 1 included 22 eyes without subconjunctival OVD injection. In 8 of these eyes, the distal end of the shunt was additionally sutured with 10.0 nylon. Group 2 comprised 25 eyes where the distal end of the shunt was sutured to the sclera, and OVD was injected under the bleb. Parameters assessed included IOP changes (mean ± standard deviation), number of used antiglaucomatous medications (mean ± standard deviation), complications, bleb scarring, and the necessity of further interventions.

Self-limiting hypotony with choroidal detachment occurred in 4 out of 47 eyes (8.5%). Hyphema in 7 eyes (15%), choroidal detachment in 2 eyes (4%), and expulsive hemorrhage in one eye (2%). Pressure spikes were found in 8 eyes in Group 1 (36%) and in 4 eyes in Group 2 (16%).

In Group 1, preoperative IOP was 21.2 ± 5.8 mmHg (2.3 ± 1.4 IOP-lowering drugs). In Group 2, preoperative IOP was 20.2 ± 6.8 mmHg (2.8 ± 1.3 drugs). After 6 months, IOP in Group 1 was 15.8 ± 6.1 mmHg (0.3 ± 0.8 drugs) and in Group 2 16.3 ± 10.3 mmHg (0.2 ± 0.7 drugs). In Group 1, 10 out of 22 eyes (45%) required bleb revision, and in Group 2 4 out of 25 eyes (16%). Six eyes (27%) in Group 1 and one eye (4%) in Group 2 required additional surgery due to failure.

Injecting OVD under the bleb at the end of Preserflo implantation can improve the success rate of IOP reduction. Choroidal detachment resulting from hypotony resolved spontaneously in all cases.