Assessing the efficacy and safety of a recently introduced type of surgical device (Preserflo Microshunt) in the treatment of glaucoma

ISRCTN	ISRCTN96192007
DOI	https://doi.org/10.1186/ISRCTN96192007

Submission date: 19/09/2021
Registration date: 11/10/2021
Last edited: 11/10/2021

Recruitment status: No longer recruiting
Overall study status: Completed
Condition category: Eye Diseases

Prospectively registered

Protocol

Statistical analysis plan

Results

Individual participant data

Record updated in last year

Plain English summary of protocol

Background and study aims
Glaucoma is a common eye disease affecting the optic nerve and leading to irreversible blindness. This disease is thought to be caused by excess pressure inside the eye. The Preserflo Microshunt is a device similar to a tube that is implanted in the front part of the eye and allows for the drainage of fluid from the eye, relieving the pressure. The aim of this study is to determine how effective is this surgery, if it effectively lowers the pressure in the long term, if it relieves the burden of eye drops in glaucoma patients, and if it is a safe surgical option.

Who can participate?
Data is extracted from patient files of any adult patient with glaucoma who has been implanted with the Preserflo Microshunt between June 2019 and September 2021 at the Hospital de Santa Maria, Centro Hospitalar e Universitário Lisboa Norte

What does the study involve?
The investigators will examine the patient charts to analyze if the surgery effectively reduced eye pressure in a safe manner throughout the patients' follow-up time.

What are the possible benefits and risks of participating?
None as this is a retrospective study

Where is the study run from?
Hospital de Santa Maria, Centro Hospitalar e Universitário Lisboa Norte (Portugal)

When is the study starting and how long is it expected to run for?
May 2019 to December 2021

Who is funding the study?
Universidade de Lisboa (Portugal)

Who is the main contact?
Rafael Barão
rafaelcbarao@gmail.com

Contact information

Dr Rafael Barão
Scientific

Av. Prof. Egas Moniz
Lisbon
1649-035
Portugal

ORCID ID	0000-0002-3102-1969
Phone	+351 (0)916316796
Email	rafael.barao@chln.min-saude.pt

Study information

Study design	Single-center cross sectional observational study
Primary study design	Observational
Secondary study design	Cross sectional study
Study setting(s)	Hospital
Study type	Treatment
Participant information sheet	Not available in web format, please use the contact details to request a patient information sheet
Scientific title	Early clinical outcomes of the Preserflo Microshunt
Study objectives	To assess the efficacy (hypotensive power) and safety (rate of complications) of the Preserflo Microshunt, an aqueous drainage shunt aimed for the treatment of medically uncontrolled glaucoma.
Ethics approval(s)	Approval pending, North Lisbon University Hospital (CHUL) and Lisbon Academic Center (CAML) Ethics Committee (Av. Prof. Egas Moniz, 1649-035 Lisboa; +351 (0)217805405; anapimentel@chln.min-saude.pt)
Health condition(s) or problem(s) studied	Intraocular pressure control in patients with glaucoma
Intervention	Data is extracted from patient files (background history, glaucoma characteristics, baseline intraocular pressure [IOP], preoperative visual acuity [VA], number of ocular hypotensive medication, intra-operative and postoperative complications, follow-up from visits on day 1; at weeks 1, 4; at months 3, 6 and 12 after Preserflo Microshunt implantation; number of postoperative IOP-lowering medication at all timepoints; and previous or subsequent surgical interventions).
Intervention type	Procedure/Surgery
Primary outcome measure	The surgical success of Preserflo Microshunt implantation at 12 months postoperative, defined as at least 30% reduction in IOP from baseline and final IOP ≤18mmHg and >5 mmHg, with (qualified success) or without hypotensive drugs (absolute success)
Secondary outcome measures	1. Mean IOP in mmHg measured using Goldmann applanation tonometry and retrieved from patient files at the last pre-operative visit and at day 1, day 7, months 1, 3, 6, 12, 18 and 24 postoperative (when respectively applicable) 2. Mean number of hypotensive drugs retrieved from patient files at the last pre-operative visit and at day 1, day 7, months 1, 3, 6, 12, 18 and 24 postoperative (when respectively applicable) 3. Intra-operative or postoperative complications retrieved from patient files at time of surgery, day 1, day 7, months 1, 3, 6, 12, 18 and 24 (when respectively applicable)
Overall study start date	01/05/2021
Completion date	01/12/2021

Eligibility

Participant type(s)	Patient
Age group	Adult
Lower age limit	18 Years
Sex	Both
Target number of participants	100
Key inclusion criteria	1. Patients submitted to Preserflo Microshunt implantation for medically uncontrolled glaucoma between June 2019 and September 2021 2. Age ≥18 years and have agreed to chart review as per GDPR regulations
Key exclusion criteria	1. Pregnancy or breastfeeding 2. Severe cardiovascular disease (including a stroke or a myocardial infarction 6 months before) 3. Known allergic reaction to MMC
Date of first enrolment	01/06/2019
Date of final enrolment	30/09/2021

Locations

Countries of recruitment

Portugal

Study participating centre

Hospital de Santa Maria, Centro Hospitalar e Universitário Lisboa Norte

Av. Prof. Egas Moniz
Lisbon
1649-035
Portugal

Sponsor information

Centro Hospitalar Lisboa Norte
Hospital/treatment centre

Av. Prof. Egas Moniz
Lisbon
1649-028
Portugal

Phone	+351 (0)217805000
Email	walter.rodrigues@chln.min-saude.pt
Website	http://www.chln.min-saude.pt/
"ROR"	https://ror.org/020sr6z07

Funders

Funder type

University/education

Universidade de Lisboa
Government organisation / Universities (academic only)

Alternative name(s): Universitas Olisiponensis, University of Lisbon, Technical University of Lisbon, ULisboa | Universidade de Lisboa, University of Lisbon, Portugal, New University of Lisbon (Portugal), ULisboa
Location: Portugal

Results and Publications

Intention to publish date	01/01/2022
Individual participant data (IPD) Intention to share	Yes
IPD sharing plan summary	Available on request
Publication and dissemination plan	The results of this study should be published in a high-visibility peer-reviewed journal.
IPD sharing plan	The datasets generated during and/or analysed during the current study are/will be available upon request from any investigators whose proposed use of the data has been approved by an independent review committee (“learned intermediary”) identified for this purpose, exclusively for individual participant data meta-analysis. Data requests should be addressed to Rafael Barão (rafael.barao@chln.min-saude.pt). Data willing to be shared will include relevant individual participant data that underlie the results reported in this article, after deidentification and anonymisation. Data requests may be submitted from 6 months to up to 24 months following article publication. Use of this data has been included in the patient consent form.

Editorial Notes

11/10/2021: Trial's existence confirmed by North Lisbon University Hospital.