Clinical trial NCT02621580: Investigating the Structural and Functional Changes to the Retina Following PRP in Diabetic Retinopathy Patients
Official title: A 24-Month Cohort Study Assessing the Nature and the Time Course of Structural and Functional Changes to the Retina Following PASCAL Photocoagulation in Proliferative Diabetic Retinopathy Patients
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Diabetic Retinopathy
Keywords: Panretinal Photocoagulation
Lead sponsor: London Health Sciences Centre Research Institute OR Lawson Research Institute of St. Joseph's
Sponsor class: OTHER
First posted: 2015-12-03
Enrollment: 24
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NON_RANDOMIZED
Intervention model: SINGLE_GROUP
Primary purpose: TREATMENT

Brief summary: Laser therapy is an established method to stabilize and control proliferative diabetic eye disease. Questions on the long-term effect on the retina from these treatments remain to be answered. The purpose of the study was to evaluate changes in the retina following panretinal photocoagulation (PRP) over time, using structural and functional diagnostic tests.

Detailed description: Diabetic retinopathy is the most common cause of adult-acquired retinal vascular disease. Diabetic retinopathy is estimated to affect more than 100 million adults, and is the leading cause of blindness worldwide.

Over the past 30 years, epidemiological studies and clinical trials have shown that early detection through annual eye exams, intensive glucose and blood pressure control, and timely laser photocoagulation could prevent visual loss. More recently, a variety of newer ocular treatments and medications have been introduced, such as the use of the PASCAL photocoagulation laser system, and various anti-vascular endothelial growth factor therapies. While these treatments have revolutionized how diabetic retinopathy patients are managed clinically, questions on appropriate patient selection and the long-term efficacy and safety of these treatments remain to be answered.

The purpose of this study is to focus on studying the nature and the time course over 2 years of structural and functional changes to the retina following PASCAL photocoagulation in severe preproliferative or proliferative diabetic retinopathy patients.

Eligibility criteria: Inclusion Criteria:

* Male or female patient's greater than 18 years of age who have signed an informed consent.
* Patients with type 1 or type 2 diabetes mellitus (according to ADA or WHO guidelines) that have severe preproliferative or proliferative diabetic retinopathy and require PRP surgery in at least one eye.
* Adequate pupil dilation and clear media to perform laser photocoagulation, HRT, OCT and visual field testing.

Exclusion Criteria:

* Advanced lens opacity (Lens opacity that excludes the ability to capture data)
* Prior PRP within the past year
* Focal laser within one year of study entry

Primary outcomes:
measure: The rate of structural and functional changes to the retinal thickness following PASCAL PRP in severe PDR patients, assessed by optical coherence tomography.
timeFrame: 2 years
Secondary outcomes:
Other outcomes:
Locations:
Study officials:
affiliation: Western University
name: Cindy Hutnik, MD, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Klein R. Prevention of visual loss from diabetic retinopathy. Surv Ophthalmol. 2002 Dec;47 Suppl 2:S246-52. doi: 10.1016/s0039-6257(02)00388-0.
citation: Lim MC, Tanimoto SA, Furlani BA, Lum B, Pinto LM, Eliason D, Prata TS, Brandt JD, Morse LS, Park SS, Melo LA Jr. Effect of diabetic retinopathy and panretinal photocoagulation on retinal nerve fiber layer and optic nerve appearance. Arch Ophthalmol. 2009 Jul;127(7):857-62. doi: 10.1001/archophthalmol.2009.135.
citation: Kim HY, Cho HK. Peripapillary retinal nerve fiber layer thickness change after panretinal photocoagulation in patients with diabetic retinopathy. Korean J Ophthalmol. 2009 Mar;23(1):23-6. doi: 10.3341/kjo.2009.23.1.23. Epub 2009 Mar 9.
citation: Muqit MM, Marcellino GR, Henson DB, Fenerty CH, Stanga PE. Randomized clinical trial to evaluate the effects of Pascal panretinal photocoagulation on macular nerve fiber layer: Manchester Pascal Study report 3. Retina. 2011 Sep;31(8):1699-707. doi: 10.1097/IAE.0b013e318207d188.