Macular Tractional Retinoschisis in Proliferative Diabetic Retinopathy

Fibrovascular tissue induced macular elevation is an important cause of visual loss in proliferative diabetic retinopathy (PDR). There are two main types of macular elevations in PDR: traction retinal detachment (TRD) and tractional retinoschisis. These two conditions may coexist either in the form of retinoschisis within the detached retina or predominantly retinoschisis with a small subfoveal fluid pocket. Optical coherence tomography (OCT) studies have shown that in tractional retinoschisis, the inner retinal layer is normal reflective; outer layer is less reflective but not optically empty. Bridging columnar tissues are frequently observed between the inner and outer layers. Histopathological study by Faulborn et al showed adherence of posterior hyaloid membrane to the retina plus vitreous body shrinkage might induce retinal elevation with splitting of the outer plexiform layer, leading to retinoschisis. The bridging columnar tissues between inner and outer layers of the split retina mainly consisted of Muller cells. Although tractional retinoschisis with or without retinal detachment has been suggested as the most frequent pattern of tractional macular elevation in eyes with proliferative diabetic retinopathy1, and peripheral retinoschisis are frequently found during operation for complications of PDR, studies on clinical manifestations and post-operative visual prognosis of macular traction schisis are limited. Lincoff reported a relatively good prognosis in eyes with tractional retinoschisis after vitrectomy. No other large series specifically aimed at this entity can be found.

In this report, we will retrospectively study the clinical pictures of tractional retinoschisis on the macula. Morphological changes and functional outcomes after surgery will be discussed. Correlations between visual acuity and specific findings on color fundus pictures and OCT will be evaluated. We will also analyze different behaviors of schisis only and combined tractional retinal detachment with schisis.