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Effect of Type of Head Positioning on Retinal Displacement in Vitrectomy for Retinal Detachment (DIAMOND)

Primary Purpose

Retinal Detachment, Metamorphopsia

Status
Recruiting
Phase
Not Applicable
Locations
Canada
Study Type
Interventional
Intervention
Face down positioning
Supine positioning
Sponsored by
Unity Health Toronto
About
Eligibility
Locations
Arms
Outcomes
Full info

About this trial

This is an interventional prevention trial for Retinal Detachment

Eligibility Criteria

18 Years - undefined (Adult, Older Adult)All SexesDoes not accept healthy volunteers

Inclusion Criteria:

  • Age ≥ 18
  • Diagnosis of primary rhegmatogenous retinal detachment needing pars plana vitrectomy with the detachment involving at least one of the temporal vascular arcades, which would allow retinal displacement to be detected on fundus autofluorescence photography

Exclusion Criteria:

  • Rhegmatogenous retinal detachment with an attached macula
  • Proliferative retinopathy grade C or worst
  • Prior vitrectomy for retinal detachment. Patients having had pneumatic retinopexy that failed to completely reattach the retina and therefore now needing vitrectomy are allowed into the study
  • History of preoperative binocular diplopia
  • Tamponade with silicone oil instead of gas
  • Inability to maintain post operation head positioning
  • Mental incapacity

Sites / Locations

  • Department of Ophthalmology, St. Michael's HospitalRecruiting

Arms of the Study

Arm 1

Arm 2

Arm Type

Active Comparator

Experimental

Arm Label

Conventional face down positioning

Supine positioning

Arm Description

Patients in third arm will be treated with the current standard of care, that is, they will be kept supine in the ophthalmic surgery chair after the completion of their surgery. They will then be taken to the recovery area where, once transferred to the care of the postoperative care unit staff, they will transition to face down positioning. They will maintain this positioning until their first day postoperative visit after which they will position according to the retinal breaks found during surgery.

Patients in the second arm will be kept supine after the completion of their surgery. They will then be taken to the recovery area where, once transferred to the care of the postoperative care unit staff, they will maintain supine positioning. They will maintain this positioning until their first day postoperative visit after which they will position according to the retinal breaks found during surgery.

Outcomes

Primary Outcome Measures

Retinal displacement
The presence of retinal vessels printing on fundus autofluorescence imaging.

Secondary Outcome Measures

Visual Distortion
measured with M chart.
Aniseikonia
Measured with aniseikonia testing. The aniseikonia test measures the ratio of image size difference between the 2 eyes
Optical coherence tomography (OCT) changes
Changes seen on OCT
Optical coherence tomography angiography (OCTA) changes
Changes seen on OCTA
Metamorphopsia
Metamorphopsia is the image distortion experienced by the patient. It will be recorded in a data collection sheet as "yes" or "no" according to the patient subjective complain on metamorphopsia.
Best corrected Visual Acuity measured in "Early Treatment of Diabetic Retinopathy Study" letters
Best corrected Visual Acuity measured in "Early Treatment of Diabetic Retinopathy Study" letters

Full Information

First Posted
February 11, 2019
Last Updated
April 27, 2021
Sponsor
Unity Health Toronto
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1. Study Identification

Unique Protocol Identification Number
NCT04035343
Brief Title
Effect of Type of Head Positioning on Retinal Displacement in Vitrectomy for Retinal Detachment
Acronym
DIAMOND
Official Title
Difference In Anatomic Integrity in Vitrectomy for Macula Off Rhegmatogenous RetiNal Detachments With Face Down Compared to Supine Positioning (the DIAMOND Study)
Study Type
Interventional

2. Study Status

Record Verification Date
April 2021
Overall Recruitment Status
Recruiting
Study Start Date
August 26, 2019 (Actual)
Primary Completion Date
October 2024 (Anticipated)
Study Completion Date
October 2024 (Anticipated)

3. Sponsor/Collaborators

Responsible Party, by Official Title
Sponsor
Name of the Sponsor
Unity Health Toronto

4. Oversight

Studies a U.S. FDA-regulated Drug Product
No
Studies a U.S. FDA-regulated Device Product
No
Data Monitoring Committee
No

5. Study Description

Brief Summary
Patients may experience metamorphopsia, or image distortion, after having vitrectomy to repair their rhegmatogenous retinal detachments especially those with a detached macula. Retinal displacement, as measured on autofluorescence photography, likely contributes to this distortion. It is thought that the retina slips inferiorly due to the residual subretinal fluid shifting as the patient transitions from the supine position intraoperatively to the sitting up position in the immediate postoperative period. By having the patient immediate position facedown or according to the retinal break, the risk of slippage is theoretically decreased.
Detailed Description
Rhegmatogenous retinal detachments (RRD) are a sight-threatening condition with an incidence of approximately 10 per 100 000 people. RRDs can be broadly classified into those with the macula still attached, and those with the macula detached. Visual prognosis for RRDs with attached macula tend to be much better than those with detached macula. Pars plana vitrectomy (PPV) is one of the procedures used to treat RRD. PPV is carried out in the operating room under regional anesthestic, and often times sedation. The retina is reattached by either draining the subretinal fluid through a peripheral retinal break, by draining the subretinal fluid through a posterior retinotomy, or by using a heavier-than-water liquid such as perfluorocarbon to push out the subretinal fluid. At the end of the surgery, the vitreous cavity is filled with a substance that will tamponade the retina to the wall of the eye. Tamponade agents can be temporary, such as sulfur hexafluoride (SF6) and octafluoropropane (C3F8), or long term, such as silicone oil. After the surgery, patients are usually told to put their facedown allowing the tamponade agent to keep the macula attached while the remaining subretinal fluid is reabsorbed by the retinal pigment epithelium. Alternatively, some surgeons ask that their patients position according to the location of their retinal breaks with the aim for the buoyant gas bubble to cover the break or breaks. Patients may experience metamorphopsia, or image distortion, after having their RRD repaired especially those with a detached macula. Retinal displacement, as measured on autofluorescence photography, likely contributes to this distortion. Supine positioning in theory covers all break locations as usually breaks occur in the anterior part of the retina near the vitreous base. This position has the advantage of being more ergonomic than face down. Depending on the results, this study might provide evidence for the current standard of care, which is face down positioning for the first day after vitrectomy for retinal detachment. Or, if supine positioning demonstrates superiority in reducing the risk of retinal displacement, patients would be able to maintain a more comfortable position after surgery.

6. Conditions and Keywords

Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Retinal Detachment, Metamorphopsia

7. Study Design

Primary Purpose
Prevention
Study Phase
Not Applicable
Interventional Study Model
Parallel Assignment
Masking
Outcomes Assessor
Allocation
Randomized
Enrollment
324 (Anticipated)

8. Arms, Groups, and Interventions

Arm Title
Conventional face down positioning
Arm Type
Active Comparator
Arm Description
Patients in third arm will be treated with the current standard of care, that is, they will be kept supine in the ophthalmic surgery chair after the completion of their surgery. They will then be taken to the recovery area where, once transferred to the care of the postoperative care unit staff, they will transition to face down positioning. They will maintain this positioning until their first day postoperative visit after which they will position according to the retinal breaks found during surgery.
Arm Title
Supine positioning
Arm Type
Experimental
Arm Description
Patients in the second arm will be kept supine after the completion of their surgery. They will then be taken to the recovery area where, once transferred to the care of the postoperative care unit staff, they will maintain supine positioning. They will maintain this positioning until their first day postoperative visit after which they will position according to the retinal breaks found during surgery.
Intervention Type
Behavioral
Intervention Name(s)
Face down positioning
Intervention Description
See description of the face down positioning group
Intervention Type
Behavioral
Intervention Name(s)
Supine positioning
Intervention Description
See description of the supine positioning group
Primary Outcome Measure Information:
Title
Retinal displacement
Description
The presence of retinal vessels printing on fundus autofluorescence imaging.
Time Frame
3 months
Secondary Outcome Measure Information:
Title
Visual Distortion
Description
measured with M chart.
Time Frame
3 months
Title
Aniseikonia
Description
Measured with aniseikonia testing. The aniseikonia test measures the ratio of image size difference between the 2 eyes
Time Frame
3 months
Title
Optical coherence tomography (OCT) changes
Description
Changes seen on OCT
Time Frame
3 months
Title
Optical coherence tomography angiography (OCTA) changes
Description
Changes seen on OCTA
Time Frame
3 months
Title
Metamorphopsia
Description
Metamorphopsia is the image distortion experienced by the patient. It will be recorded in a data collection sheet as "yes" or "no" according to the patient subjective complain on metamorphopsia.
Time Frame
3 months
Title
Best corrected Visual Acuity measured in "Early Treatment of Diabetic Retinopathy Study" letters
Description
Best corrected Visual Acuity measured in "Early Treatment of Diabetic Retinopathy Study" letters
Time Frame
3 months

10. Eligibility

Sex
All
Minimum Age & Unit of Time
18 Years
Accepts Healthy Volunteers
No
Eligibility Criteria
Inclusion Criteria: Age ≥ 18 Diagnosis of primary rhegmatogenous retinal detachment needing pars plana vitrectomy with the detachment involving at least one of the temporal vascular arcades, which would allow retinal displacement to be detected on fundus autofluorescence photography Exclusion Criteria: Rhegmatogenous retinal detachment with an attached macula Proliferative retinopathy grade C or worst Prior vitrectomy for retinal detachment. Patients having had pneumatic retinopexy that failed to completely reattach the retina and therefore now needing vitrectomy are allowed into the study History of preoperative binocular diplopia Tamponade with silicone oil instead of gas Inability to maintain post operation head positioning Mental incapacity
Facility Information:
Facility Name
Department of Ophthalmology, St. Michael's Hospital
City
Toronto
State/Province
Ontario
ZIP/Postal Code
M5C 2T2
Country
Canada
Individual Site Status
Recruiting
Facility Contact:
First Name & Middle Initial & Last Name & Degree
Rajeev Muni, MD Msc FRCSC
Phone
4168677411
Email
Rajeev.Muni@unityhealth.to
First Name & Middle Initial & Last Name & Degree
Phillip To
Phone
4168677411
Email
Philip.To@unityhealth.to

12. IPD Sharing Statement

Learn more about this trial

Effect of Type of Head Positioning on Retinal Displacement in Vitrectomy for Retinal Detachment

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