Cataract Surgery with Near Normal Eye Pressure in Patients with Diabetic Retinopathy (NNIOP-PHACO)

Near Normal Intraocular Pressure Cataract Surgery in Patients with Diabetic Retinopathy Using Active Anterior Chamber Pressure Sensing and Regulation - a Randomized Controlled Comparative Clinical Trial

Diabetes mellitus is a chronic metabolic disease that can lead to visual impairment and eye complications such as diabetic retinopathy and diabetic macular edema. Diabetics are considered a vulnerable patient group for cataract surgery, as microincision phacoemulsification (MICS) in diabetics is associated with a higher risk of postoperative swelling of the macula and cornea (macular or corneal edema). In addition, the ultrasound energy emitted during MICS, high and fluctuating intraocular pressure and the movement of surgical instruments and lens material are the main causes of surgical trauma. The medical device "Centurion Vision System" with the "Active Sentry" handpiece was developed specifically to improve the stability of the anterior chamber during surgery and to enable operations at low, almost normal physiological intraocular pressure settings.

The central question of the study is therefore, whether a stable intraocular pressure close to physiological normal conditions (28 mmHg) during surgery can lead to a reduction in surgical trauma. In this prospective and randomized study, patients suffering from diabetes and having a planned bilateral MICS are included in one of two study arms:

A) The participant is operated on with an IOP of 28 mm Hg in the better eye and an IOP of 50 mm Hg in the worse eye or B) the participant is operated on with an IOP of 28 mm Hg in the worse eye and an IOP of 50 mm Hg in the better eye.

Study Overview

• Status: Active, not recruiting
• Conditions: Diabetic Retinopathy; Cataract
• Intervention / Treatment: Device: Ophthalmosurgical handpiece with active anterior chamber pressure sensing and regulation

• Study Type: Interventional
• Enrollment (Estimated): 72
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Austria
  • Innsbruck, Austria, 6020
    • Medical University Innsbruck, University Hospital for Ophthalmology and Optometry

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Indication for immediate sequential bilateral microincision cataract surgery
2. Diagnosis of Diabetes Mellitus treated with oral medication or insulin therapy and confirmed by HbA1c ≥6,5 %
3. Presence of diabetic retinopathy grade ≥1 on the international clinical diabetic retinopathy (ICDR) severity scale
4. LOCS 2-4 with no more than 1 grade difference between both eyes
5. Male or female patient aged 50 - 85 years of age at time of consent
6. Understands and agrees to comply with the study procedures and provides written informed consent as documented by signature

Exclusion Criteria:

1. Participation in another clinical trial within 30 days before pre-screening and throughout the trial
2. Prior intraocular surgery of any type
3. History of diabetic macular edema
4. Presence of macular edema, defined as central retinal thickness of >300 µm plus intraretinal or subretinal fluid on OCT within range of 1mm of foveal center
5. Presence of any retinal or choroidal disease, other than diabetes, that could affect retinal thickness
6. Known history of uveitis
7. Documented use of systemic or topical steroid or other immunosuppressive medication within the last 3 months
8. ACF >10 ph/ms. ACF difference between right and left eye > 4ph/ms
9. Difference of DRP grading between right and left eye of more than 1 grade (ICDR)
10. Inability to measure total macular volume due to, but not limed to, too dense cataract, vitreous bleeding
11. Woman of childbearing potential (WOCBP) who is breastfeeding, has a positive urine pregnancy test, is not willing to undergo a urine pregnancy test upon entering or exiting the study, intends to become pregnant during the study, or does not agree to use adequate birth control methods for the duration of the study
12. Patients in possession of an active implantable medical device (AIMD)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: A) IOP 28mmHg on the better eye and IOP 50mmHg on the worse eye; Near normal intraocular pressure cataract surgery using active anterior chamber pressure sensing and regulation	Device: Ophthalmosurgical handpiece with active anterior chamber pressure sensing and regulation; Cataract surgery in patients with diabetic retinopathy using active anterior chamber pressure sensing and regulation
Other: B) IOP 28mmHg on worse eye and IOP 50mmHg on the better eye; Near normal intraocular pressure cataract surgery using active anterior chamber pressure sensing and regulation	Device: Ophthalmosurgical handpiece with active anterior chamber pressure sensing and regulation; Cataract surgery in patients with diabetic retinopathy using active anterior chamber pressure sensing and regulation

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Delta ACF	Difference from pre- to postoperative ACF (delta ACF) at day 1 (FU1) and day 7 (FU2) after cataract surgery.	1 week

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
BCVA	Difference between pre- to postoperative BCVA	1 month
5mm corneal volume	Pentacam derived	1 month
Anterior chamber depth	Pentacam derived	1 month
Mydriatic pupil width	Pentacam derived	1 month
Endothelial cell density	Quantifying assessment of endothelial cell loss via specular microscopy; (28 +-3) days after surgery.	1 month
Assessment of intraoperative complications	Screening for the presence of posterior capsular ruptures	1 month
Assessment of postoperative complications	Presence of cystoid macular edema	1 month
Intraoperative events	Assessment of any event in regard to phacoemulsification settings	Day 0 (Surgery)
Central macular thickness	Pre- and postoperative assessment of central macular thickness via optical coherence tomography (OCT)	1 month
Total macular volume	Pre- and postoperative assessment of total macular volume via optical coherence tomography (OCT)	1 month
Retinal Nerver fiber layer thickness (RNFL)	Pre- and postoperative assessment of RNFL via optical coherence tomography (OCT)	1 month
Central corneal thickness	Pre- and postoperative assessment of central corneal thickness via optical coherence tomography (OCT)	1 month

Collaborators and Investigators

• Sponsor: Medical University Innsbruck

Study record dates

Study Major Dates

• Study Start (Actual): August 21, 2024
• Primary Completion (Estimated): September 1, 2025
• Study Completion (Estimated): September 30, 2025

Study Registration Dates

• First Submitted: September 11, 2024
• First Submitted That Met QC Criteria: September 24, 2024
• First Posted (Actual): September 27, 2024

Study Record Updates

• Last Update Posted (Actual): September 27, 2024
• Last Update Submitted That Met QC Criteria: September 24, 2024
• Last Verified: September 1, 2024

More Information

Terms related to this study

• Keywords: Intraocular pressure; Cataract; Phacoemulsification; Diabetic Retinopathy; Microincision Phacoemulsification; Active anterior chamber pressure
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Eye Diseases; Endocrine System Diseases; Diabetic Angiopathies; Diabetes Complications; Diabetes Mellitus; Lens Diseases; Retinal Diseases; Diabetic Retinopathy; Cataract
• Other Study ID Numbers: NNIOP-PHACO

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No