·Post operative vitreous hemorrhage following vitrectomy has an incidence varying between 29-75%.
The causes of early vitreous hemorrhage are
1.dispersed blood from the peripheral vitreous skirt, oozing from the cut end of vessels,
2. hypotony
3.Clotted blood
4.Port side trickling of blood
This may clear on its own in 2-3 weeks and may be managed by fluid air exchange if it persists. Intraocular tamponade with 10% C3F8 in vitrectomy for proliferative diabetic retinopathy has been reported to be associated with reduction of early postoperative vitreous hemorrhage. Preoperative avastin helps in diabetic vitrectomy and reduces the need for extensive segmentation and delamination , decreasing the chance of significant early vitreous hemorrhage.Late recurrent hemorrhage is due to
1.fibrovascular ingrowth (FVIG) at the sclerotomy sites,
2.anterior hyaloidal proliferation,
3.neovascularisation of residual fibrovascular tissue;
4.neovascularisation of angle or iris .
This can be treated with intravitreal Bevacizumab, vitreous lavage with additional laser, anterior retinal cryothreapy (ARC) and in severe cases dissection of the vascular membranes followed by laser cryo and tamponade. It is often indicated by a dilated episcleral vessel entering the previous sclerotomy site 25. UBM of the sclerotomy site may show a large and low reflecting trapezoidal image indicating its presence26. Anterior peripheral retinal cryotherapy combined with cryotherapy of sclerotomy sites in patients undergoing diabetic vitrectomy has been advised for inhibition of FVIG and prevention of recurrent vitreous hemorrhage27.
- compiled & published by Dr Dhaval Patel MD AIIMS
