Macular Hole in Diabetic Retinopathy
Condition: Macular Hole; Proliferative Diabetic Retinopathy
MeSH terms: Retinal Diseases; Diabetic Retinopathy; Retinal Perforations
Study type: Observational

Summary: 
      Macular hole in proliferative diabetic retinopathy with fibrovascular proliferation may have
      unique features. Internal limiting membrane peeling facilitates hole closure only in cases
      with shallow macular detachment. Final vision is associated with preoperative visual acuity
      and degree of macula elevation.
    

Detailed description: 
      From January 2002 to December 2007 consecutive patients undergo pars plana vitrectomy for
      diabetic fibrovascular proliferation and the medical and surgical records are reviewed.

      Diabetic fibrovascular proliferation associated with macular hole that had undergone pars
      plana vitrectomy with a minimum of 6 months of post-operative follow-up will be
      retrospectively reviewed. Cases fulfilling the indication criteria will be selected for the
      study All operations had been performed following the same principle and techniques.

      Demographics and clinical findings of each case will be recorded including age, sex, involved
      eye, duration of macular hole, intraoperative diagnosis, extent of vitreo-retinal adhesion
      and detachment, morphology of macular hole, and relationship of macular hole to posterior
      hyaloid and fibrovascular proliferation. Data regarding treatment of macular hole, final
      opening or closure of macular hole, and duration of postoperative follow-up will also be
      compiled. Results of ophthalmological examinations, including pre- and post-operation best
      corrected visual acuity, intraocular pressure, and intravitreal tamponade material will be
      recorded. Optical coherence tomography (OCT) findings will be categorized and recorded.
      Retinal detachment severity will be classified as: no traction retinal detachment (TRD) or
      TRD within arcade (grade 1); TRD outside arcade, but not to or beyond the equator (grade 2);
      and RD extended to the periphery in at least 1 quadrant (grade 3). The degree of macular
      elevation surrounding the macular hole will be classified into three grades according to pre-
      or intra-operative observation: shallow: barely visible macular detachment with or without
      fine retinal folds and with underlying choroidal patterns still identifiable through the
      detached retina; moderate: obvious detachment with folds and loss of visualization of
      underlying choroidal patterns; and high: convex shaped or dome shaped detachment with wavy
      configuration in the macular area. Extent of fibrovascular proliferation will be separated
      into 3 grades: grade 1: focal adhesions only; grade 2: broad adhesion at more than 1 site or
      vitreous-retinal adhesion at disc, macula or arcade; and grade 3: vitreous-retinal attachment
      extending to the periphery.

      Statistical Analysis To examine the significance of various clinical findings in relation to
      final macular hole closure rate, statistical analysis of the data is performed with
      chi-squared test or Fisher's exact test. To further verify the clinical characteristics and
      treatments that affecting macular hole closure, multivariate logistic regression analysis is
      performed to determine the significance of the following factors: age, sex, operation eye,
      duration of macular hole, RD extent, submacular fluid level, extent of fibrovascular
      proliferation, macular hole shape, and intravitreal tamponade materials. An association of
      post-operative best-corrected visual acuity with other study variables is assessed by
      multiple lineal regression analysis, using backward Wald's criteria, taking post-operation
      best-correted visual acuity as the dependent variable. All of the statistical analyses are
      performed using STATA 8.2 software (StataCorp LP, College Station, Texas, USA). A P value <
      0.05 is considered statistically significant.
    

Observational model: Cohort
Time perspective: Retrospective
Sampling method: Non-Probability Sample
Study population: 
        Paitient with proliferative diabetic retinopathy
      
Keywords: Fibrovascular proliferation; Internal limiting membrane peeling; Macular detachment; Macular hole; Proliferative diabetic retinopathy.