Changes in Retinal Nerve Fiber Layer Thickness Detected by OCT in Diabetic Retinopathy After Panretinal Photocoagulation

• Conditions: Retinal Disease

• Registration Number: NCT03786146
• Lead Sponsor: Assiut University

Brief Summary

Panretinal photocoagulation reduces the risk of visual loss by 50% in patients with diabetic retinopathy. It is recognized that laser expansion into the retina may be associated with photoreceptor loss, retinal pigment epithelial hypertrophy and visual field loss.

Panretinal photocoagulation can cause alteration in retinal vascular permeability therefore, retinal thickness may be increased including retinal nerve fiber layer. On the contrary, it can damage retinal cells including ganglion cells, which may decrease the retinal nerve fiber layer thickness in the latter follow up period.

Peripapillary retinal nerve fiber layer can be measured by optical coherence tomography which is a non-invasive technique for obtaining high resolution cross sectional images of a tissue.

Detailed Description

Pre laser assessment:

* Assessment of medical and family history

* Refraction and best corrected visual acuity

* Anterior segment examination using binocular slit lamp bi-microscopy.

* Posterior segment examination.

* OCT scan of peripapillary area

Post laser assessment ( at 1,3 and 6 months):

* Refraction and best corrected visual acuity.

* Anterior segment examination using binocular slit lamp bi-microscopy.

* Posterior segment examination.

* OCT scan of peripapillary area.

Study Timeline

• Status Verified: 2018-12
• Study First Submitted: 2018-12-14
• Study First Submitted QC: 2018-12-21
• Last Update Submitted: 2018-12-21
• Study First Posted: 2018-12-24
• Last Update Posted: 2018-12-24
• Study Start: 2019-01-01
• Primary Completion: 2019-11
• Study Completion: 2019-12

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 30

Inclusion Criteria

• Patients with a clinical diagnosis of proliferative diabetic retinopathy.
• Treated by panretinal photocoagulation.
• Age between 40-70 years old.

Exclusion Criteria

• Patients with densely opaque media (as dense cataract or vitreous hemorrhage).
• Glaucomatous patients.
• Any other associated retinopathy.

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Retinal nerve fiber layer thickness measured by Optical Coherence Tomography (OCT) and expressed in micrometers.	6 months post laser treatment.	A 3.4 mm OCT circular scan will be positioned around the optic nerve head.