The first step in any case of TRD should be to trim and release for 360° the peripheral vitreous cone. In TRDs, the vitreous is usually detached in the midperiphery, but multiple attachments remain at the posterior pole, thus forming a vitreous cone. Most cases of RRD will have a complete PVD, whereas this is uncommon in TRDs. The vitreous in diabetic and other TRDs differs significantly from the vitreous in an eye with routine rhegmatogenous retinal detachment (RRD). Attention is then turned toward tackling the peripheral vitreous (Video /?v=opool.) If vitreous hemorrhage is present, it is cleared in the standard fashion. Color and red-free photographs are also helpful and should be reviewed the night before surgery. Spectral-domain optical coherence tomography (OCT) imaging is helpful in assessing the level and severity of the membranes and can provide clues regarding the location of potential spaces where safe dissection or initiation of membrane removal can be performed. All strategies employed are geared toward avoiding breaks in the ischemic, fragile retina. Therefore, the chief surgical goal of TRD repair includes complete release of the hyaloid with dissection of all tractional fibrous membranes. This cascade of events explains why an eye in a patient with diabetes is protected from a TRD if a complete posterior vitreous detachment (PVD) has occurred before any evidence of neovascularization. With time, the vitreous can contract and exert tractional forces on the retina via these fibroglial connections, leading to a TRD. Subsequently, glial cell proliferation encases these vessels in fibrous tissue. The new vessels then break through the internal limiting membrane and grow along the surface of the retina and into the scaffold of the posterior hyaloid face. These growth factors lead to the development of fragile new vessels from the existing retinal veins. Progressive retinal ischemia leads to pathologic secretion of growth factors, especially VEGF. Tractional retinal detachment (TRD) may occur in a number of conditions, such as proliferative diabetic retinopathy (PDR), retinal vein occlusion, trauma, sickling hemoglobinopathies, and retinopathy of prematurity. Incomplete removal of the hyaloid is the most common cause of failure.Segmentation and delamination of the membranes and release of the posterior hyaloid is the second major step.360° trimming of the peripheral vitreous cone is the essential first step in tractional retinal detachment surgery.
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