Evaluation of Retinal Toxicity by ERG Before and After Pars Plana Vitrectomy in ILM Peeling Assisted by Brilliant Blue G Staining at a Concentration of 1 mg/ml, 6 Months of Follow Up

Abstract

Purpose: : To evaluate in vivo retinal toxicity after surgical application of brilliant blue G using a 1 mg/ml concentration with standard electroretinogram (ERG).

Methods: : Fourteen patients underwent phacoemulsification with IOL implantation and pars plana vitrectomy with peeling of the internal limiting membrane (ILM) assisted with 1 mg/ml concentration of brilliant blue G. Gas tamponade with SF6 was used in all cases. Best corrected visual acuity (BCVA) measurement and ERG were performed prior to surgery, one and six months afterwards. Macular hole architecture and closure were evaluated clinically and by spectral domain optical coherence tomography (SD-OCT).

Results: : 10 female and 4 male were enrolled in the study with a mean age of 66.84 ±5.88 years. A sufficient staining of the ILM was seen in all cases and peeling was successfully achieved. BCVA improved one line. Clinical observation showed closure of all macular holes and was confirmed by SD-OCT. B-wave amplitude on maximal ERG was 335.43±116.31µV preoperatively and 330.03 ±88.27 µV at 3 months and 309.52 ±12.20 µV at 6 months postoperatively (p=0.56). Implicit time on maximal ERG was 68.18 ±35.72 msec preoperatively and 50.53 ±3.17 msec at 3 months and 50.6 ±5.22 msec at 6 months postoperatively (p=0.77).

Conclusions: : Using a concentration of 1 mg/ml of brilliant blue G in the treatment of macular hole for staining the ILM seems to have no retinal toxicity detected by ERG at 6 months of follow up; and has the same visual outcome as previous concentrations reported. More patients and further studies are needed.

Keywords: drug toxicity/drug effects • electrophysiology: clinical • macular holes