The ADVISE Study: Advanced Visualization In Corneal Surgery Evaluation
- Conditions
- Endothelial Corneal DystrophyBullous KeratopathyFuchs DystrophyVision Disorders
- Interventions
- Device: intraoperative optical coherence tomography (iOCT)
- Registration Number
- NCT03763721
- Lead Sponsor
- UMC Utrecht
- Brief Summary
Rationale: Intra-operative optical coherence tomography (iOCT) is a new technology that incorporates advanced imaging techniques in the ophthalmic operating theatre. This allows surgeons to visualize tissues in a way previously impossible We conceptualized an iOCT-guided surgical protocol for the treatment of endothelial cell dysfunction, that refrains from the current practice of over-pressurizing the eye at the end of surgery.
Objective: The aim of this study is to assess the clinical value of intraoperative OCT (iOCT) for Descemet Membrane Endothelial Keratoplasty (DMEK) by comparing an iOCT-optimized surgical protocol with current practice, where the eye is over-pressurized for a set period of time, in terms of surgical efficiency, clinical outcomes, and adverse events.
Study design: International multicentre non-inferiority randomized clinical trial Study population: Patients scheduled for posterior lamellar corneal surgery for endothelial cell dysfunction above the age of 18 years.
Intervention: Both groups will undergo Descemet Membrane Endothelial Keratoplasty. Patients will be randomized for either the iOCT optimized surgical protocol or current standard surgical protocol using 8 minutes of overpressure to facilitate graft adherence. Both groups will be evaluated with iOCT at the end of surgery.
Main study parameters/endpoints:
The main study parameter is the rate of adverse events (particularly graft dislocations). Secondary parameters/endpoints are surgical time, the recovery of visual acuity and endothelial graft quality at 3 and 6 months follow-up, and a detailed evaluation of the extent/duration of surgical tissue manipulations.
Nature and extent of the burden and risks associated with participation, benefit and group relatedness: The use of iOCT during surgery does not entail additional risk to the patient. Participants to this study will adhere to the standard of care after corneal transplant surgery. In addition, they will receive study specific measurements and questionnaires. The additional measurements and questionnaires will be combined with regular follow up moments.
- Detailed Description
Not available
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 65
- Age ≥ 18 years
- Irreversible corneal decompensation caused by Fuchs corneal endothelial dystrophy or pseudophakic bullous keratopathy
- Eligible for posterior lamellar keratoplasty, specifically Descemet Membrane Endothelial Keratoplasty (DMEK)
- Any ocular co-morbidity other than cataract, mild dry eye disease, ocular hypertension, simple primary open angle glaucoma, and mild age-related macular degeneration
- Prior corneal transplant surgery
- Human leukocyte antigen (HLA) matched keratoplasty
- Any disability that will interfere with performing or understanding the procedures and questionnaire fulfilment except if it is temporary of nature.
- Combined phaco-emulsification-DMEK surgery (triple procedure)
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description current practice protocol (CP-p) intraoperative optical coherence tomography (iOCT) In the current practice protocol (CP-p), graft apposition will be obtained using a complete and pressurized (approx. 65mmHg) filling of the anterior chamber with 20% SF6, for 8 minutes. Tissue manipulations, such as corneal swiping, will be performed as deemed necessary by the surgeon, based on the en face view from the conventional microscope image. The intraocular pressure is normalized by exchanging the SF6 gas for BSS, to achieve a gas bubble approximately the size of the graft (i.e 8.5mm). Now, the graft apposition is assessed using iOCT, to ensure all trial patients eventually undergo advanced iOCT imaging. Should this iOCT image reveal improper graft adherence or any other irregularity, the surgeon will perform additional manipulations or interventions as deemed necessary iOCT optimized protocol (iOCT-p) intraoperative optical coherence tomography (iOCT) In the iOCT optimized protocol (iOCT-p) group, graft apposition will be assessed with special detail for graft orientation, interface fluid, and any peripheral folds as described by Xu et al. Potential tissue manipulations will be therefore based on the iOCT image. Apposition of the graft will be obtained using a complete filling of the anterior chamber with 20% sulphur hexafluoride (SF6) endotamponade for 1-2 minutes, whilst the OCT image is assessed and any graft manipulation can be performed if deemed necessary. After this period, the gas is partly exchanged for BSS (Balanced Salt Solution, Alcon) to achieve a bubble with a diameter of approximately the same size of the graft (i.e. 8.5mm)
- Primary Outcome Measures
Name Time Method rate of the most relevant post-operative surgical complications within 6 weeks post-operatively the number of patients that develop adverse events relating to lamellar corneal surgery, specifically graft detachments that necessitate a surgical intervention, early graft failures that lead to intractable corneal edema, or induced iatrogenic acute glaucoma
- Secondary Outcome Measures
Name Time Method Surgical manipulations during surgery the recorded videos will be reviewed and scored considering the amount of surgical manipulations, the duration of all steps of the procedure, and the use of iOCT. All according to a study specific standard operating procedure
Surgical time during surgery times are recorded at entry of the OR, start time of the surgery, actual first incision, timepoint for injection of gas, duration of gas, closing time and departure time of the OR. Out of these both skin-to-skin and overall time in surgery can be calculated (i.e. gross/net)
Best-corrected visual acuity 3 and 6 months follow-up Visual acuity is assessed using an ETDRS (Early Treatment Diabetic Retinopathy Study Chart) visual acuity chart with a spectacle correction. Visual acuity measurement ranges from light perception, hand movements, finger counting, 0.05 till 1.0. (US equivalent 20/20)
Graft endothelial cell densities 3 and 6 months follow-up The quality of the graft is based on the amount and viability of endothelial cells. These will be measured (number of cells/mm2, variation in size (variation coefficient), hexagonality-coefficient) with in vivo specular microscopy.
Trial Locations
- Locations (3)
Universiteitsziekenhuis Leuven
🇧🇪Leuven, Belgium
Maastricht University Hospital
🇳🇱Maastricht, Netherlands
University Medical Center Utrecht
🇳🇱Utrecht, Netherlands