Clinical trial NCT00906659: Visual Function, Center Point Thickness and Macular Volume After Photocoagulation
Official title: Correlation of Visual Function, Center Point Thickness and Macular Volume Changes Three Weeks After Focal Photocoagulation for Diabetic Macular Edema
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Diabetic Retinopathy
Macular Edema
Keywords: center point thickness
diabetic retinopathy
diabetic macular edema
macular volume
visual capacity
visual function
Lead sponsor: Hospital Juarez de Mexico
Sponsor class: OTHER_GOV
First posted: 2009-05-21
Enrollment: 89
Sex: ALL
Minimum age (years): 40
Maximum age (years): 70
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: CASE_ONLY
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Target population were type 2 diabetics from Mexico City and its metropolitan area, accessible population were the patients who attended a General Hospital in Mexico City

Brief summary: The purpose of this study is to correlate changes of visual function three weeks after photocoagulation for macular edema, with changes of center point thickness and macular volume.

Detailed description: Photocoagulation for clinically significant macular edema is effective to reduce the incidence of moderate visual loss. Selective photocoagulation for focal macular edema statistically reduces macular thickening, measured with optical coherence tomography, as early as two weeks after treatment, without significant changes over center point thickness. Although anatomic improvement has been demonstrated with OCT, clinical improvement takes longer to be evident: the Early Treatment Diabetic Retinopathy Study describe that clinical differences in visual function are after the eight month, and all the treatment strategies for macular edema used in this study were associated with an increased rate of moderate visual loss, during the first six weeks. Differences in research can achieve statistical significance, without clinical significance. A study was conducted to identify changes of visual function three weeks after photocoagulation for focal macular edema, and to correlate them with changes of CPT and macular volume, in order to compare the behavior of anatomical changes with visual changes.

Eligibility criteria: Inclusion Criteria:

* type 2 diabetes
* regardless of diabetes duration and retinopathy severity level
* one or both eyes with focal clinically significant macular edema
* treated with selective or focal photocoagulation
* visual capacity under subjective refraction before and three weeks after treatment
* adequate quality 6 mm fast macular map both on the day of photocoagulation, and three weeks after it

Exclusion Criteria:

* patients with myopia over -6.00 diopters
* any retinal disease different from diabetic retinopathy at the moment of photocoagulation
* eyes with a thickened posterior vitreous
* eyes with vitreoretinal traction at the macula
* if they had required scatter photocoagulation before the three weeks evaluation

Primary outcomes:
measure: visual capacity (under subjective refractive correction was measured in decimal equivalent)
timeFrame: before the treatment and 3 weeks after photocoagulation
measure: center point thickness (measured in µm)
timeFrame: before the treatment and 3 weeks after photocoagulation
measure: macular volume (measured in mm3)
timeFrame: before the treatment and 3 weeks after photocoagulation
Secondary outcomes:
Other outcomes:
Locations:
city: Mexico
country: Mexico
facility: Hospital Juarez de Mexico
state: Distrito Federal
Study officials:
affiliation: Hospital Juarez de Mexico
name: Dulce M Razo Blanco Hernandez, MD
role: STUDY_DIRECTOR
affiliation: Hospital Juarez de Mexico
name: Virgilio Lima Gomez, MD, MSc
role: STUDY_CHAIR
affiliation: Hospital Juarez de Mexico
name: Aleyda S Cruz Diaz, MD
role: PRINCIPAL_INVESTIGATOR
References: