Aqueous Release to Treat IOP Spikes Post-cataract Surgery

Sponsor
Bedford Hospital NHS Trust (Other)
Overall Status
Unknown status
CT.gov ID
NCT03500809
Collaborator
(none)
20
1
11

Study Details

Study Description

Brief Summary

Intraocular pressure (IOP) rise after cataract surgery is an important and common problem. Over 300,000 cataract operations are done per year in the United Kingdom alone. IOP rise can adversely affect vision and can be particularly detrimental in glaucoma patients with pre-existing visual field defects. The aim of this study is to evaluate the efficacy and safety of aqueous humor release (also known as burping of the wound), a procedure that has been used for decades to quickly reduce acute IOP spikes following cataract surgery.

Currently there is no published evidence on a standard technique to perform wound burping. Similarly there is uncertainty around the amount and duration of the IOP decrease, and the type and frequency of complications eventually associated. This will be the first research project formally evaluating this procedure. This study will also help allay issues over fluid release in high IOPs and consequences of such dramatic IOP drop which concerns ophthalmologists who do not routinely use this technique.

Condition or Disease Intervention/Treatment Phase
  • Procedure: Aqueous release of the wound
N/A

Detailed Description

At present there is no de facto standard to manage acute intraocular pressure (IOP) rise following cataract surgery. Several drugs, both topical and systemic, have been tested for their ability to blunt the acute IOP spike, nevertheless none has proven to be superior and consistently effective. Oral acetazolamide has demonstrated to help controlling IOP spikes following cataract surgery in glaucomatous eyes. However there are still constraints in its widespread use, as it may be contraindicated in patients with poor renal function, sickle cell disease and sulpha drug allergy.

As a result, many units including Moorfields Eye Hospital have used a technique called known as 'burping of the corneal wound' to release fluid from inside the anterior chamber of the eye. This makes logical sense as it reduces the pressure immediately and may remove some of the causes for raised IOP such as retained viscoelastic and inflammatory molecules from inside the eye. This technique has also been used to reduce IOP in patients already receiving pharmaceutical treatment.

The technique has been used for decades, however, there is no published evidence of a proposed technique, range of IOP decrease or frequency of complications. Thus, most surgeons in most units are cautious of 'burping the wound' as it may induce infection or other complications compromising the surgical outcome due to the sudden reduced IOP reduction. Nevertheless a similar approach, needle penetrating the eye to release aqueous and reduce IOP, is becoming more popular as the first approach to treat an acute angle closure crisis, where the presenting IOP is often very high, i.e. a much more difficult and dangerous situation than post cataract surgery.

Study Design

Study Type:
Interventional
Anticipated Enrollment :
20 participants
Allocation:
N/A
Intervention Model:
Single Group Assignment
Masking:
None (Open Label)
Primary Purpose:
Treatment
Official Title:
Efficacy and Safety of Aqueous Humour Release (Burping) Performed at the Slit-lamp to Treat Acute Intraocular Pressure (IOP) Spikes Post-cataract Surgery
Anticipated Study Start Date :
Aug 12, 2018
Anticipated Primary Completion Date :
Jan 12, 2019
Anticipated Study Completion Date :
Jul 12, 2019

Arms and Interventions

Arm Intervention/Treatment
Experimental: Aqueous release (Burping) of the wound

Following uneventful cataract surgery, wound "burping" will be performed in all eligible patients who gave their informed consent. The procedure will be offered whenever the intraocular pressure (IOP) is either higher than 30 mmHg or deemed inappropriate in view of the ocular condition (e.g. glaucoma). After 'burping' the wound, patients will have their IOP measured using Goldmann application tonometry (GAT) immediately and at 2 hours. The 'burping' procedure will be repeated until satisfactory pressure is achieved and care will be taken to avoid shallowing of the anterior chamber while fluid is released. We will assess for the presence of leaks from the wound with a Seidel test with fluorescein 5% once the IOP is satisfactory. To prevent any infection after each procedure, we will prescribe post-op drops including chloramphenicol 0.5% four times a day for 2 weeks or minimum of 3 days and these will continue as per routine. All other complications will be recorded at follow-up.

Procedure: Aqueous release of the wound
Anaesthetic drop (tetracaine 1%) followed by povidone iodine 5% drop is instilled. After 5 minutes, a sterile 30 gauge needle tip is pressed on the posterior lip of the one of the existing cuts (paracentesis or main wound) from cataract surgery to release the fluid and consequently the pressure. This will be performed under careful monitoring to avoid any undesirable shallowing of the anterior chamber of the eye.
Other Names:
  • 'Burping' procedure
  • Outcome Measures

    Primary Outcome Measures

    1. Efficacy of 'burping' the wound to reduce IOP (mmHg) post-cataract surgery when measured using Goldmann application tonometry (GAT) [6 months]

      Reduction in IOP (mmHg) post-cataract surgery after the 'burping' procedure

    Secondary Outcome Measures

    1. Range of IOP decrease (mmHg) [6 months]

      To observe and record the range of IOP decrease (mmHg) from individual 'burping' procedures

    2. Frequency of complications post-'burping' procedure [6 months]

      Observing the frequency of complications, including but not limited to, severe pain, worsening of vision, or infection

    Eligibility Criteria

    Criteria

    Ages Eligible for Study:
    18 Years to 90 Years
    Sexes Eligible for Study:
    All
    Accepts Healthy Volunteers:
    No
    Inclusion Criteria:
    • Patient whose post-operative IOP was regarded to be too high for visual safety, or higher than 30mmHg, on the same day or within 1 week of the surgery
    Exclusion Criteria:
    • Patients with IOP less than 30 mmHg or IOP deemed by clinician not too high to treat

    • Patients unable to cooperate

    • Patients who have undergone complicated cataract surgery

    Contacts and Locations

    Locations

    No locations specified.

    Sponsors and Collaborators

    • Bedford Hospital NHS Trust

    Investigators

    • Principal Investigator: Anant Sharma, MBBS, FRCOphth, Bedford Hospital Moorfields Eye Unit

    Study Documents (Full-Text)

    None provided.

    More Information

    Publications

    Responsible Party:
    Anant Sharma, Consultant Ophthalmic Surgeon, Bedford Hospital NHS Trust
    ClinicalTrials.gov Identifier:
    NCT03500809
    Other Study ID Numbers:
    • IRAS 240539
    First Posted:
    Apr 18, 2018
    Last Update Posted:
    Jul 27, 2018
    Last Verified:
    Jul 1, 2018
    Individual Participant Data (IPD) Sharing Statement:
    No
    Plan to Share IPD:
    No
    Studies a U.S. FDA-regulated Drug Product:
    No
    Studies a U.S. FDA-regulated Device Product:
    No
    Additional relevant MeSH terms:

    Study Results

    No Results Posted as of Jul 27, 2018