Robotic RVO Trial: Robot-assisted Retinal Vein Cannulation in Patients With Retinal Vein Occlusions

NCT07820761 | Active Not Recruiting

• 2 other identifiers: 1875434223
• Study Type: interventional
• Target: 40
• Locations: 1 country
• Sites: 1

Brief Summary

Retinal vein occlusions (RVOs) are the second leading cause of permanent vision loss in the UK. Current treatments, like anti-VEGF injections or steroids, address complications such as macular fluid but do not target the underlying issue-a clot in the retinal vein. Direct injection of clot-dissolving agents, such as tissue plasminogen activator (tPA), is challenging due to the small size of retinal veins. This surgical trial aims to inject tPA directly into the blocked retinal vein to dissolve the clot and restore blood flow. This surgical trial aims to inject tPA directly into the blocked retinal vein to dissolve the clot and restore blood flow. Robotic assistance will stabilise the injection cannula, ensuring precise and slow infusion of tPA. This study will compare outcomes in patients receiving standard care for RVOs (the control group) with those receiving standard treatment plus the robot-assisted tPA injection (the study group). The robotic system has been clinically validated and has received CE marking for vitreoretinal interventions, including tPA injection beneath the retina. tPA has been safely used in the eye with no reported safety concerns. It is licensed for intravenous use for thromboembolic events that lead to ischemia. RVO (an ischemic stroke of the eye) is a specific example. Instead of systemic administration through the peripheral vein, we will be directly delivering tPA into the occluded retinal vein, effectively treating the localised ischemia, within licensed intent. 40 eligible participants diagnosed with RVO will be recruited from the NHS clinic. Participants will be randomly allocated to the control group or the study group and will be monitored for 12 months. The study focuses on safety as the primary outcome and efficacy in terms of retinal structure and function as secondary outcomes. If successful, this trial could lead to a new intervention for RVO-related vision loss.

Conditions

Retinal Vein Occlusion (RVO)

Keywords

Ophthalmology; RVO; Retinal Vein Occlusion; Surgical Robot

Outcome Measures

Primary Outcomes (1)

• Safety of robot-assisted retinal vein cannulation

  Evaluation of safety will be based on the potential number of procedure-related adverse events.

  Baseline to 12 months

Secondary Outcomes (3)

• To evaluate change in visual acuity

  Baseline to 12 months

• To evaluate change in central macular thickness

  Baseline to 12 months

• To evaluate changes in area of the non-perfused retina

  At all protocol-specified visits with the endpoint at 12 months.

Study Arms (2)

Control Arm ( NHS Standard of Care Surgery)

NO INTERVENTION

Participants randomised to the control arm will receive NHS standard of care surgery.

Interventional Arm ( NHS Standard of Care Surgery + Robot)

ACTIVE COMPARATOR

Participants randomised to the interventional arm will receive robot-assisted vein cannulation and infusion into the blocked vein during the NHS standard of care surgery.

Procedure: Surgery with Preceyes Robot plus NHS standard of care

Interventions

Surgery with Preceyes Robot plus NHS standard of care PROCEDURE

Central Retinal Vein cannulation and infusion into the blocked vein using the Preceyes Robot, while following NHS standard of care

Interventional Arm ( NHS Standard of Care Surgery + Robot)

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Participant is wiling and able to give informed consent for participation in the trial
• Male or Female aged 18 years or above
• Recently diagnosed with central RVO (\<4 weeks)
• In the Investigator's opinion, the patient is able and willing to comply with all trial requirements and is deemed fit for treatment.
• ETDRS BCVA letter score of 70 or less or Snellen equivalent (\< 6/12) in the study eye at Screening Visit 1

You may not qualify if:

• Participants with comorbidities contraindicating vitreoretinal surgery (e.g. excessive tremor) as determined by the investigator.
• Participants with ocular comorbidities contraindicating the use of steroid implants (e.g. glaucoma) or anti-VEGFs as determined by the investigator.
• Participants who are participating in another research trial involving an investigational product or surgical intervention.
• Participants with known allergy to Fluorescein
• Participants with contraindications for the use of tPA (Alteplase, Boehringer Ingelheim, Germany) or currently receiving or starting medications that have a known interaction with tPA, as identified in the SmPC, which may alter its efficacy or safety profile of tPA.

Sponsors & Collaborators

• University of Oxford: lead

Study Sites (1)

Eye Research Group Oxford, Oxford Eye Hospital, LG1, West Wing of the John Radcliffe Hospital

Oxford, Oxfordshire, OX3 9DU, United Kingdom

Location

MeSH Terms

Conditions

Retinal Vein Occlusion

Interventions

Surgical Procedures, Operative

Condition Hierarchy (Ancestors)

Retinal Diseases; Eye Diseases; Venous Thrombosis; Thrombosis; Embolism and Thrombosis; Vascular Diseases; Cardiovascular Diseases

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: CARE PROVIDER
• Masking Details: The ETDRS-BCVA assessment for visits 1, 5,6,7, 8, 9, 10 and 11 will be conducted by a masked assessor who will be blinded to the arm the participant is randomised to. An unmasked assessor will conduct the assessment for visits 2, 3 and 4 to maintain masking and reduce bias.
• Purpose: OTHER
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: June 3, 2026
• First Posted: September 15, 2026
• Study Start: September 1, 2025
• Primary Completion (Estimated): March 30, 2027
• Study Completion (Estimated): March 30, 2028
• Last Updated: September 15, 2026

Record last verified: 2026-03

Locations

GB (1)