Purpose:
to describe an unusual pattern of retinal hemorrhages after pars-plana vitrectomy for macular hole using silicone oil tamponade.Material and
Methods:
perspective study on a continuous series of 103 eyes of 97 patients with full thickness macular hole stage II-IV, operated on between February 2000 and September 2008. Pars-plana vitrectomy 20G was performed. Indocyanine green 0,025% or Trypan Blue 0,15% were used to enhance internal limiting membrane peeling with a 2 to 1 ratio. Vitreous cavity was filled with silicone oil 1000 centystokes.
Results:
Since the first day after surgery in 53 eyes (51,5%) we observed the presence of round intraretinal midperipheral hemorrhages when silicon oil was used as tamponade and wasn’t related to the used dye. They persist until the oil is removed, i.e. after one month. This is a curious phenomenon since it doesn’t occur in other vitreal surgeries in which silicon oil is used. The only difference between tamponade for macular holes and a retinal detachment, for instance, is that in the first case our goal is to obtain a perfectly dry retinal surface, in order to achieve an intraoperative closure of the hole. This complete filling of vitreal cavity in our opinion can be in some way responsible of the hemorrhages. We feel that the closed contact between the oil bubble and the retinal capillaries interpheres with their metabolic activity and finally damages them. In some cases fluorescein angiography would suggest a vasculitic process (staining and leakage of the veins), but other patients don’t have the same angiographic pattern.
Conclusions:
we feel that silicon oil tamponade is responsible of retinal hemorrhages in macular hole surgery, but this phenomenon still needs a more precise explanation.
Keywords: macular holes • vitreoretinal surgery • vitreous substitutes