Abstract
Purpose: :
Myofibroblasts play a major role in the production of retractile phenomena causing contraction or shrinkage of the epiretinal membranes (ERM) in proliferative vitreoretinopathy, diabetic retinopathy or idiopathic macular epiretinal membranes. To evaluate the expression of myofibroblasts on epiretinal macular tissue, in eyes with diabetic retinopathy undergoingvitrectomy.
Methods: :
Samples of ERMs and/or ILMs following macular surgery in eyes with diabetic maculopathy or other diabetic-related complications were collected in 13 eyes. Samples included ILMs only in 7 eyes, ERMs only in 2 eyes and ERM with ILM in 4 eyes. Double immunofluorescence staining with antibodies recognizing a-SMA and ED-A FN or vimentine in myofibroblasts, followed by confocal microscopy analysis as well as electronic microscopy were performed in all samples.
Results: :
a-SMA in association to either ED-A FN or vimentine were detected in all ERM samples with or without ILM. In addition, ED-A FN or vimentine was expressed in close relation with a-SMA-positive myofibroblasts in 2 out of 7 ILM samples.
Conclusions: :
Scanning electron microscopy indicated that myofibroblats cellular migration is always expressed in epiretinal macular membrane. Most (5/7) of the ILM samples were negative for myofibroblasts, whereas 2 stained positive. These results suggest that in some cases ILM may contain myofibroblasts with no macroscopic evidence of ERM. If during surgery, the ILM is colored inhomogeneously, this suggests the presence of cells and should be peeled. If the ILM is colored homogeneously, peeling is not considered necessary.
Keywords: diabetic retinopathy