Evaluation of the Posterior Hyaloid Changes Following Intravitreal Injection of Ranibizumab for Diabetic Macular Edema

Purpose
The aim of this work was to evaluate the posterior hyaloid changes and the effect on the vitreomacular relationship following intravitreal injection of ranibizumab (lucentis) for DME in diabetic patients attending the outpatient clinic of the Ophthalmology Department in Alexandria Main University Hospital.
Patients and methods
The study included 40 eyes. All of them received a baseline injection of 0.5 mg of intravitreal ranibizumab under sterile conditions. The injection was performed under topical anesthesia, with or without sedation. Further injections were administered Pro Re Nata (PRN ‘as required’) as decided in each subsequent follow-up visit if central retinal thickness remained 300 μm or greater or if there was a decrease in best-corrected visual acuity due to DME progression, confirmed with clinical evaluation and/or optical coherence tomography or other anatomic and clinical assessments.
Results
There were 12 male (54.2%) and 10 female patients (45.5%) between 45 and 71 years of age, with a mean value of 63.2 ± 12.6. There were five patients (22.7%) with type I and 17 patients (77.3%) with type II DM. The duration of DM was less than 10 years in six patients (27.3%) and more than 10 years in 16 patients (72.7%); it ranged between 9.5 and 20 years, with a mean value of 15.11 ± 7.98 years. HbA1c ranged from 7.11 to 8.25, with a mean value of 7.72 ± 0.892, and baseline visual acuity (TTDRS) ranged from 7.11 to 8.25, with a mean value of 53.13 ± 12.22. Baseline central macular thickness ranged from 301.0 to 525.0, with a mean value of 413.0 ± 107.0. No vitreous separation (category 1) was observed in 19 cases (47.5%), partial vitreomacular separation (VMS) (category 2) was observed in 12 cases (30%), vitreofoveal attachment with no traction (category 3) in seven cases (17.5%), and finally vitreofoveal attachment with traction (dome-shaped profile) (category 4) was observed in two cases (5%). No changes in vitreomacular relationship was seen in 16 cases (40%), partial VMS was seen in six cases (15%), vitreofoveal attachment with no traction was seen in eight cases (20%), vitreofoveal attachment with traction (dome-shaped profile) in three cases (7.5%), and complete VMS was seen in seven cases (17.5%). There was a statistically significant difference with regard to number of changes in VMR, partial VMS, vitreofoveal attachment with no traction, and vitreofoveal attachment with traction (dome-shaped profile). There was a statistically significant difference with regard to partial VMS, vitreofoveal attachment with no traction, and vitreofoveal attachment with traction (dome-shaped profile). There was a statistically significant relation between the number of injections and the outcome; the higher the number of injections, the better is the outcome.