Visual Field Progression and RNFL Change After PreserFlo MicroShunt Implantation

Study Overview
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Brief Summary
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The trabeculectomy is the gold standard in glaucoma surgery, nevertheless often postoperative interventions have to be done. (1),(2) The PreserFlo MicroShunt (Santen, Osaka, Japan) implantation occurs without critical steps of trabeculectomy. (3) According to a study a 20% eye pressure reduction was achieved in 53.9% of patients one year after PreserFlo MicroShunt implantation and the risk of postoperative hypotony was clearly minimized. (4) It has been shown that after trabeculectomy there is a stable development of visual fields in the first 3 months after surgery and then, despite adequate intraocular pressure reduction, visual fields deteriorate. (5) At the Klinikum Klagenfurt structural and functional changes after PreserFlo MicroShunt Implantation shall be evaluated.

Official Title
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Visual Field Progression and RNFL Change After PreserFlo MicroShunt Implantation - a Prospective Cohort Study at the Ophthalmology Department Klinikum Klagenfurt

Conditions
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Glaucoma, Progression, Surgery

Intervention / Treatment
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* Device: PreserFlo Microshunt


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with insufficient eye pressure control despite IOP (intraocular pressure)-lowering therapy Diagnosis of POAG (primary open angle glaucoma) Diagnosis of PEG (pseudoexfoliation glaucoma) Diagnosis of PDG (pigment dispersion glaucoma) Diagnosis of NTG (normal tension glaucoma) Agreement of patients to participate in the study Exclusion Criteria: Previous glaucoma surgery Visual acuity of Nulla Lux Poor general condition Pregnancy Exudative macular degeneration

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 100 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Device: PreserFlo Microshunt|The PreserFlo MicroShunt was invented to create a minimally invasive glaucoma drainage device, that comes close to the eye pressure reduction and safety profile of the current gold standard, the trabeculectomy. Reference: Pinchuk L, Riss I, Batlle JF, Kato YP, Martin JB, Arrieta E, Palmberg P, Parrish RK 2nd, Weber BA, Kwon Y, Parel JM. The development of a micro-shunt made from poly(styrene-block-isobutylene-block-styrene) to treat glaucoma. J Biomed Mater Res B Appl Biomater. 2017 Jan;105(1):211-221. doi: 10.1002/jbm.b.33525. Epub 2015 Sep 18. PMID: 26380916; PMCID: PMC5215625.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Visual field progression (mean deviation, MD) 1 month postoperative, 3 months postoperative, 6 months and 12 months postoperative after PreserFlo MicroShunt Implantation. | Visual fields of patients at baseline preoperative and 1 month postoperative, 3 months postoperative, 6 months postoperative and 12 months postoperative should be compared. | Visual fields taken at baseline should be compared to visual fields 1 month postoperativ, 3 months postoperative and 1 year postoperative. | 
| RNFL (retinal nerve fiber layer) at baseline before sugery and changes after1 month, 3 months, 6 months and 12 months postoperative after PreserFlo MicroShunt Implantation will be evaluated. | The measurement of the nerve fiber will be compared at baseline before surgery to the values at 1 month, 3 months, 6 months and 12 months after surgery. | The measurement of the nerve fiber index shall be done at baseline before surgery and 1 month, 3 months, 6 months and 12 months after surgery. | 
| Intraocular pressure will be taken 1 month, 3 months, 6 months and 12 months after PreserFlo MicroShunt Implantation. | The evaluation of the intraocular pressure shall be done 1 month, 3 months, 6 months and 12 months after surgery. | The intraocular pressure will be taken postoperative after one month, 3 months, 6 months and 12 months. |