---
title: Vienna Preserflo Cohort Study
nct_id: NCT04541524
overall_status: UNKNOWN
sponsor: Medical University of Vienna
study_type: OBSERVATIONAL
primary_condition: Glaucoma
countries: Austria
canonical_url: "https://parkinsonspathways.com/agent/trials/NCT04541524.md"
clinicaltrials_gov: "https://clinicaltrials.gov/study/NCT04541524"
ct_last_update_post_date: 2020-09-09
last_seen_at: "2026-05-12T06:57:07.014Z"
source: ClinicalTrials.gov (mirrored, no enrichment)
---
# Vienna Preserflo Cohort Study

**Official Title:** Vienna Preserflo Microshunt Cohort Study

**NCT ID:** [NCT04541524](https://clinicaltrials.gov/study/NCT04541524)

## Key Facts

- **Status:** UNKNOWN
- **Study Type:** OBSERVATIONAL
- **Target Enrollment:** 70
- **Lead Sponsor:** Medical University of Vienna
- **Conditions:** Glaucoma, Glaucoma Surgery, Post-Op Complication, Efficacy, Self, Safety Issues
- **Start Date:** 2020-06-05
- **Completion Date:** 2020-11-30
- **CT.gov Last Update:** 2020-09-09

## Brief Summary

The Vienna Preserflo Microshunt Cohort Study is an observational study with a prospective postoperative examination in all glaucoma patients who had received a Preserflo Microshunt (PMS) as standalone procedure or in combination with cataract extraction in the time period between January and November 2019 at the Department of Ophthalmology, Medical University of Vienna. It is estimated that approximately 70 patients will be included of this cohort. The cohort will be invited for a prospective postoperative examination after 12 (±5) months of follow up. This examination shall comprise best corrected visual acuity, visual field test, intraocular pressure (IOP) measurement, slit lamp examination, fundus examination (optic disc and retina), gonioscopic assessment of PMS position, anterior segment optical coherence tomography (OCT) (shunt position, anterior chamber angle assessment, limbus shape analysis), corneal pachymetry, specular microscopy of corneal endothelial cells. Additionally, retrospective information concerning IOP, medication and visual fields of all patients will be collected from the Department of Ophthalmology as well as from the referring ophthalmologists where possible. Additionally, we will perform a comparison between two groups to compare differences in outcome measures.

## Detailed Description

During the inclusion period two slightly different surgical approaches have been used. At the beginning of the surgery, the conjunctiva is opened and the Tenon capsule is getting dissected from the sclera. In the first group of patients (group 1) we made a fornix based conjunctival opening, prepared a 1mm wide and long scleral pocket in 3mm distance from limbus and placed the PMS in the anterior chamber via a 25G needle track. In the second group (group 2) the conjunctival opening was 3.5 mm from the limbus, the scleral pocket was prepared at 3.5 mm distance from the limbus and a 27G needle was used. The outcomes of these two groups will be compared.

## Eligibility

- **Minimum age:** 18 Years
- **Maximum age:** 95 Years
- **Sex:** ALL

```
Inclusion Criteria:

* Glaucoma patients who received a PMS in the time period between January and November 2019 at the Department of Ophthalmology, Medical University of Vienna, Austria, will be invited

Exclusion Criteria:

* Unwilling or unable to give informed consent.
* Pregnancy or lactation
```

## Interventions

- **Santen Preserflo Microshunt** (DEVICE) — The PMS is 8.5 mm long has an outer diameter of 350 μm and a lumen diameter of 70 μm. It has a fin sized 1.1 mm located 4.5 mm distally from the internal tip of the device and it consists of poly(styrene-b-isobutylene-b-styrene) SIBS. The device was implanted 1 year prior to the present study via an ab externo approach. At the beginning of the surgery, the conjunctiva was opened. In the first group of patients (group 1) we made a fornix based conjunctival opening, prepared a 1mm wide and long scleral pocket in 3mm distance from limbus and placed the PMS in the anterior chamber via a 25G needle track. In the second group (group 2) the conjunctival opening was 3.5 mm from the limbus, the scleral pocket was prepared at 3.5 mm distance from the limbus and a 27G needle was used. PMS guides aqueous humor from the anterior chamber to the subconjunctival space. The forming filtering bleb absorbs aqueous humor which leads to IOP reduction.

## Primary Outcomes

- **IOP** _(time frame: one year)_ — IOP in mmHg
- **Full success** _(time frame: one year)_ — IOP below 21 and IOP reduction of at least 20% from baseline without medication
- **Qualified success** _(time frame: one year)_ — IOP below 21 and IOP reduction of at least 20% from baseline with or without medication
- **Complications** _(time frame: one year)_ — Number of complications per eye

## Secondary Outcomes

- **Re-intervention rate rate** _(time frame: one year)_
- **Medication rate** _(time frame: one year)_
- **Average medication** _(time frame: one year)_
- **OCT - shunt entry** _(time frame: one year)_
- **OCT - shunt clearance** _(time frame: one year)_
- **OCT - shunt length** _(time frame: one year)_
- **Corneal endothelial cell count** _(time frame: one year)_

## Locations (1)

- Insitute of Ophthalmology and Optometry, Medical University of Vienna, Vienna, Austria — _RECRUITING_

## Recent Field Changes (last 30 days)

- `status.overallStatus` — added _(2026-05-12)_
- `status.primaryCompletionDate` — added _(2026-05-12)_
- `status.completionDate` — added _(2026-05-12)_
- `status.lastUpdatePostDate` — added _(2026-05-12)_
- `design.enrollmentCount` — added _(2026-05-12)_
- `eligibility.criteria` — added _(2026-05-12)_
- `eligibility.minAge` — added _(2026-05-12)_
- `eligibility.maxAge` — added _(2026-05-12)_
- `eligibility.sex` — added _(2026-05-12)_
- `outcomes.primary` — added _(2026-05-12)_
- `outcomes.secondary` — added _(2026-05-12)_
- `armsInterventions.interventions` — added _(2026-05-12)_
- `sponsor.lead` — added _(2026-05-12)_
- `results.hasResults` — added _(2026-05-12)_
- `locations.insitute of ophthalmology and optometry, medical university of vienna|vienna||austria` — added _(2026-05-12)_

---

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