Reduction of Foveal Sensitivity in Eyes With Diabetic Macular Edema

Reduction of Foveal Sensitivity in Eyes With Diabetic Macular Oedema, With and Without Centre Involvement

Clinically significant macular edema (CSME) is a thickening of the macula associated with the risk of visual loss, which increases its centre is involved. Functional evaluation of the macula relies on best corrected visual acuity; however, neural dysfunction in diabetic eyes appears before retinal thickening and visual loss. Retinal sensitivity decreases in eyes with CSME, but it is unknown whether it differs between eyes with and without centre thickening.

Aim: To compare the reduction of foveal sensitivity in eyes with CSME, with and without centre thickening.

Study Overview

• Status: Completed
• Conditions: Diabetic Retinopathy; Clinically Significant Macular Edema

Detailed Description

A non-experimental, comparative, prospective, cross-sectional study was conducted. Target population were type 2 diabetics, from Mexico City and its metropolitan area, and available population were type 2 diabetics who attended an Ophthalmology service from a general hospital in Mexico City, from September 2011 to May 2012.

Type 2 diabetic patients aged 30-85 years, from any gender, with central fixation, whose ocular media allowed obtaining an adequate quality Optical Coherence Tomography, who had CSME with focal angiographic pattern were included. Eyes with optic nerve or visual pathways diseases or any other ocular disease that decreased Best corrected visual acuity, were excluded. Diabetic patients without retinopathy who fulfilled the remaining selection criteria were evaluated as the reference group.

Sixty degrees colour fundus photographs were obtained in all the patients using a Visucam lite ocular fundus camera; in group 1 it was verified that no signs of diabetic retinopathy existed in the photographs; CSMO was diagnosed by biomicroscopy under mydryasis, according to the ETDRS criteria.

Retinal thickness was measured using Stratus optical coherence tomography (OCT), version 4.0.1 (Zeiss). The 6 mm fast macular map strategy was used, according to the following standardised operating procedure: mydriasis ≥6mm, inclusion of the spherical equivalent and anteroposterior axis, and optimisation of z axis and of polarisation; the photograph was taken with flash between 9:00 and 11:00, using an acquisition strategy for dark irises. The maps were obtained by the same investigator, independent from the one who evaluated the patients clinically; any deviation of the OCT line regarding the actual retina boundary was considered as a measurement error.

A 10° macular perimetry was obtained in all the patients, using a Humphrey field analyser model 750i (software version 4.1); the sixteen points evaluated were arbitrarily labelled. Retinal thickness within 3 mm from the centre of the fovea was measured in 9 fields, according to the fast macular map.

• Study Type: Observational
• Enrollment (Actual): 60

Contacts and Locations

Study Locations

• Mexico
  • Distrito Federal
    • Mexico, Distrito Federal, Mexico, 07760
      • Virgilio Lima Gomez

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 30 years to 85 years (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

target population were type 2 diabetics, from Mexico City and its metropolitan area, and available population were type 2 diabetics who attended an Ophthalmology service from a general hospital in Mexico City, from September 2011 to May 2012

Description

Inclusion Criteria:

• Type 2 diabetic patients
• aged 30-85 years
• from any gender
• with central fixation
• ocular media allowed obtaining an adequate quality Optical coherence tomography
• CSME with focal angiographic pattern

Exclusion Criteria:

• optic nerve or visual pathways diseases or any other ocular disease that decreased Best corrected visual acuity

Study Plan

How is the study designed?

Number of groups / cohorts

3

Cohorts and Interventions

Group / Cohort
eyes without diabetic retinopathy; eyes of patients with diabetes mellitus type 2 that does not have retinopathy
CSME without centre involvement; eyes with CSME without thickening in the 500 µm adjacent to the centre of the macula
CSME with centre involvement; eyes with CSME with thickening in the 500 µm adjacent to the centre of the macula

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
foveal sensitivity	the ability of the fovea to perceive a light stimulus in 16 central points, which is measured in dB with a 10 degree central macular perimetry	1 day

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Retinal thickness	measured in µm, according to the automatic value generated by the fast macular map of the optical coherence tomography	1 day

Collaborators and Investigators

• Sponsor: Hospital Juarez de Mexico
• Investigators: Study Chair: VIRGILIO LIMA GOMEZ, PhD, Hospital Juárez de México; Principal Investigator: Dulce M Razo Blanco Hernandez, MSc, Hospital Juárez de México

Study record dates

Study Major Dates

• Study Start: January 1, 2013
• Primary Completion (ACTUAL): June 1, 2013
• Study Completion (ACTUAL): July 1, 2013

Study Registration Dates

• First Submitted: March 26, 2013
• First Submitted That Met QC Criteria: April 4, 2013
• First Posted (ESTIMATE): April 5, 2013

Study Record Updates

• Last Update Posted (ESTIMATE): July 11, 2013
• Last Update Submitted That Met QC Criteria: July 10, 2013
• Last Verified: July 1, 2013

More Information

Terms related to this study

• Keywords: perimetry; diabetic retinopathy; clinically significant macular edema; foveal thickness; foveal sensitivity
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Immune System Diseases; Eye Diseases; Endocrine System Diseases; Diabetic Angiopathies; Diabetes Complications; Diabetes Mellitus; Retinal Degeneration; Macular Degeneration; Hypersensitivity; Retinal Diseases; Diabetic Retinopathy; Macular Edema; Edema
• Other Study ID Numbers: HJM2021/11-B