Ocular Hypotony and Refractive Predictability in RRD Surgery (HYP-RRD)

Kazakh Eye Research Institute

Status: Not yet enrolling

Conditions: Hypotony Ocular; Rhegmatogenous Retinal Detachment

Treatments: Procedure: Combined Phacovitrectomy with Intraocular Lens Implantation and Silicone Oil Tamponade; Procedure: Silicone Oil Removal

Study type: Interventional

Funder types: NETWORK

Identifiers

NCT07283614

IRB-194-2024

Details and patient eligibility

About

This study evaluates how preoperative ocular hypotony (Goldmann IOP ≤ 7 mmHg) affects refractive predictability, axial length measurements, and visual outcomes in patients undergoing combined phacovitrectomy with silicone oil for rhegmatogenous retinal detachment.

Full description

This observational cohort study is designed to evaluate the impact of preoperative ocular hypotony (defined as Goldmann IOP ≤ 7 mmHg) on refractive outcomes, biometry parameters, and visual acuity after combined phacovitrectomy for RRD. All included eyes undergo standard 25-gauge pars plana vitrectomy with cataract extraction with IOL implantation, endolaser photocoagulation, and silicone oil tamponade.

The study population consists of eyes with primary RRD and stratified into two cohorts according to preoperative IOP:

Hypotony group - eyes with Goldmann IOP ≤ 7 mmHg; Control group - eyes with normal preoperative IOP .

Enrollment: 45 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

1. Diagnosis of primary rhegmatogenous retinal detachment (RRD);
2. Single-stage combined phacovitrectomy with clear corneal phacoemulsification with IOL implantation and 25G pars plana vitrectomy with silicone oil tamponade in the study eye;

4. Preoperative intraocular pressure (IOP) in the study eye measured by Goldmann applanation tonometry: Hypotony group: IOP ≤ 7 mmHg Normotony group: IOP > 7 mmHg 5. Planned silicone oil removal approximately 3 months after the initial combined surgery and ability to attend follow-up for refractive assessment 1 month after silicone oil removal; 6. Age (e.g., ≥18 years) and ability to provide informed consent;

Exclusion criteria

1. Previous intraocular surgery in the study eye;
2. Secondary or complex RRD associated with ocular trauma, uveitis or other active intraocular inflammation, proliferative diabetic retinopathy or other advanced vascular retinopathies, significant ocular malformations or congenital anomalies of the globe or posterior segment, pre-existing advanced glaucoma or uncontrolled ocular hypertension, or other optic nerve pathology that could confound visual and refractive outcomes, corneal opacity, significant corneal irregularity, or media opacity precluding reliable biometry or accurate axial length measurement in the study eye, systemic diseases or autoimmune conditions with known ocular involvement that may affect the retina, choroid, or refraction.

Trial design

Primary purpose: Treatment

Allocation: Non-Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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45 participants in 2 patient groups

RRD Patients with Ocular Hypotony

Active Comparator group

Description:

Patients with primary rhegmatogenous retinal detachment (RRD) and preoperative ocular hypotony, defined as Goldmann intraocular pressure (IOP) ≤ 7 mmHg, undergoing combined phacoemulsification and IOL implantation, pars plana vitrectomy with silicone oil tamponade. Silicone oil is planned to be removed approximately 3 months after the initial combined surgery and detailed refractive assessment is performed 1 month after silicone oil removal. This cohort is used to evaluate the impact of preoperative hypotony on axial length measurements, refractive predictability (MAE, % within ±0.50 D), and visual outcomes.

Treatment:

Procedure: Silicone Oil Removal

Procedure: Combined Phacovitrectomy with Intraocular Lens Implantation and Silicone Oil Tamponade

RRD patients with normal IOP

Active Comparator group

Description:

Patients with primary rhegmatogenous retinal detachment (RRD) and normal preoperative IOP (\> 7 mmHg) undergoing the same combined phacovitrectomy with IOL implantation and silicone oil tamponade. Silicone oil is planned to be removed approximately 3 months after the initial combined surgery and detailed refractive assessment is performed 1 month after silicone oil removal. This cohort serves as the comparison group for the hypotony arm to determine whether normal preoperative IOP is associated with more accurate axial length measurements, better refractive predictability, and comparable or superior visual outcomes.

Treatment:

Procedure: Silicone Oil Removal

Procedure: Combined Phacovitrectomy with Intraocular Lens Implantation and Silicone Oil Tamponade