To determine whether triamcinolone acetonide (TA) can facilitate residual posterior vitreous hyaloid removal in pars plana vitrectomy (PPV), we examined the ultrastructure of inner limiting membrane (ILM) removed in TA-assisted PPV for diabetic macular edema (DME).Patients and Methods:
In this retrospective series of 38 eyes of 37 patients who underwent PPV and ILM removal for diffuse DME with posterior hyaloid attachment, 24 eyes underwent standard PPV without TA (control group), and 14 eyes underwent TA-assisted PPV (TA group). Excised ILMs during PPV were examined by transmission electron microscopy (control group, n = 20; TA group, n = 10) or scanning electron microscopy (control group, n = 4; TA group, n = 4).Results:
Transmission electron microscopy clearly demonstrated that the ratio of the posterior vitreous hyaloid remaining on ILM was significantly lower (P = 0.0187) in the TA group than in the control group and also that TA-assisted PPV successfully removed posterior hyaloid in five of seven eyes with TA granules remaining on the retinal surface even after surgical separation of the posterior vitreous. Scanning electron microscopy enabled spatial analysis of the residual posterior hyaloid on ILM, which appeared in a patchy fashion in the control group.Conclusions:
TA-assisted PPV clearly demonstrated the residual posterior hyaloid on ILM and allowed more efficient removal of the posterior hyaloid than standard PPV.