Scientific Online Resource System

Bulgarian Review of Ophthalmology

Efficacy of the PreserFlo MicroShunt in patients with open-angle glaucoma: a retrospective study

Vesselin Daskalov, Ralitsa Kermedchieva


Introduction: Over the last decade, the surgical treatment of glaucoma has undergone evolution with the introduction of microimplants. Considered the gold standard until recently, the classic trabeculectomy, introduced by Cairns in 1968, was replaced by minimally invasive glaucoma surgery (MIGS).

Aim: The purpose of this study is to present the efficacy of PreserFlo MicroShunt (Santen, Osaka, Japan) draining intraocular fluid into the subconjunctival space with the formation of a bleb, similar to classic trabeculectomy.

Materials and Methods: A retrospective analysis was performed including patients with open-angle glaucoma after MIGS, with PreserFlo implantation and the administration of MMC: 0.4 mg/mL for 2 min, intraoperatively.

A total of 43 patients (50 eyes) were included, of whom 22 men (51.16%) and 21 women (48.84%). The average age was 65.26 years (32–91 years). The implantations were carried out within the period 2020–2023, with a follow-up period of two years.

Results: After the performed procedure, we reported the effectiveness of the PreserFlo in lowering intraocular pressure (IOP) with 82% of the cases having values </= 18 mmHg, with or without therapy, as well as success of the surgical treatment with similar results. Furthermore, a reduction in medication therapy was reported, with 91.3% not requiring such postoperatively during the follow-up period of 2 years, as well as a low rate of reoperation (15.2%).

Conclusion: With its unique design, promising efficacy and minimal invasiveness during implantation, PreserFlo would be a good tool of choice in the treatment of open-angle glaucoma.


glaucoma, glaucoma surgery, MIGS, MIBS, PreserFlo

Full Text


Saeed E, Gołaszewska K, Dmuchowska DA, Zalewska R, Konopińska J. The PreserFlo MicroShunt in the Context of Minimally Invasive Glaucoma Surgery: A Narrative Review. Int J Environ Res Public Health. 2023;20(4):2904. doi: 10.3390/ijerph20042904.

Qidwai U, Jones L, Ratnarajan G. A comparison of iStent combined with phacoemulsification and endocyclophotocoagulation (ICE2) with the PreserFlo MicroShunt and XEN-45 implants. Ther Adv Ophthalmol. 2022;14:25158414221125697. doi: 10.1177/25158414221125697.

Pinchuk L, Wilson GJ, Barry JJ, Schoephoerster RT, Parel JM, Kennedy JP. Medical applications of poly(styrene-block-isobutylene-block-styrene) ("SIBS"). Biomaterials. 2008;29(4):448-60. doi: 10.1016/j.biomaterials.2007.09.041.

Chou J, Turalba A, Hoguet A. Surgical Innovations in Glaucoma: The Transition From Trabeculectomy to MIGS. Int Ophthalmol Clin. 2017;57(4):39-55. doi: 10.1097/IIO.0000000000000192.

Pillunat KR, Herber R, Haase MA, Jamke M, Jasper CS, Pillunat LE. PRESERFLO™ MicroShunt versus trabeculectomy: first results on efficacy and safety. Acta Ophthalmol. 2022;100(3):e779-e790. doi: 10.1111/aos.14968.

Baker ND, Barnebey HS, Moster MR, Stiles MC, Vold SD, Khatana AK, et al. Ab-Externo MicroShunt versus Trabeculectomy in Primary Open-Angle Glaucoma: One-Year Results from a 2-Year Randomized, Multicenter Study. Ophthalmology. 2021 Dec;128(12):1710-1721. doi: 10.1016/j.ophtha.2021.05.023.

Scheres LMJ, Kujovic-Aleksov S, Ramdas WD, de Crom RMPC, Roelofs LCG, Berendschot TTJM, et al. XEN® Gel Stent compared to PRESERFLO™ MicroShunt implantation for primary open-angle glaucoma: two-year results. Acta Ophthalmol. 2021;99(3):e433-e440. doi: 10.1111/aos.14602.



Font Size

About The Authors

Vesselin Daskalov
Pentagram Eye Hospital, Sofia

Ralitsa Kermedchieva
Pentagram Eye Hospital, Sofia