Efficacy And Safety Profile Of The Preserflo™ Microshunt In Patients With Medically Resistant Glaucoma: A Large Single-Centre Retrospective Cohort Study

The Preserflo Ab-Externo Microshunt is inserted under the conjunctiva and Tenon’s capsule to form a filtering bleb that lowers intraocular pressure (IOP). This study aims to quantify the efficacy of Preserflo in lowering IOP and to evaluate its safety profile.

All patients were operated on and followed up by the lead glaucoma surgeon and his trainees at the East Lancashire Hospitals NHS Trust over two years.

Retrospective single-centre cohort study of 100 consecutive eyes followed up for at least 3 months post Preserflo implantation over a period of two years. The primary outcome measure was the World Glaucoma Association guidelines for complete and qualified surgical success. Complete success is defined as an IOP ≤ 21mmHg without the use of antiglaucoma medication and qualified success as an IOP ≤ 21mmHg with or without medication. Secondary outcome measures were the incidence of complications and reinterventions to assess the safety profile of the procedure.

100 procedures were performed in 94 patients. The pre-op cohort’s baseline IOP of 30.2 ± 12.1 mmHg was significantly reduced to 14.4 ± 6.41 mmHg (p<0.01). 63.2% of patients achieved the complete success criteria and 87.7% achieved qualified success. The use of antiglaucoma medication was reduced from 3.10 ± 0.94 to 0.81 ± 1.14 (p<0.01). Complications encountered include: hyphaema (8), transient hypotony (4), macular oedema (4), corneal oedema (2), scarring (2), vitreous haemorrhage (1), and shunt extrusion through the conjunctiva (1). Surgical reinterventions included: bleb revision (9), bleb needling (5), stent manipulation (4), trabeculoplasty (1), trabeculectomies (2), anti-VEGF injection (2), and Baerveldt tube insertion (2).

The Preserflo Microshunt is an effective and minimally invasive option for managing glaucoma surgically. The procedure achieved significant reductions in IOP and the burden of antiglaucoma medication in the majority of patients. While there were complications and reinterventions required in a minority of cases, the overall safety profile of the procedure remains strong.