Inferior retinotomy and silicone oil tamponade for recurrent inferior retinal detachment and grade C PVR in eyes previously treated with pars plana vitrectomy or scleral buckle.

BACKGROUND: One of the most challenging problems in vitro-retinal surgery is the recurrence of retinal detachment in the context of high-grade proliferative vitreoretinopathy (PVR). The aim of our retrospective study was to assess the surgical outcomes of pars plana vitrectomy, 180° inferior retinotomy and silicone oil tamponade combined with phacoemulsification and IOL implantation for recurrent inferior retinal detachment with grade C PVR in phakic eyes. The study was carried out at tertiary referral centre - University Hospital of Rome "Tor Vergata". METHODS: Retrospective analysis of 33 eyes affected by recurrent inferior retinal detachment and grade C PVR after primary encircle scleral buckling (SB group - 12 eyes), or pars plana vitrectomy (PPV group - 21 eyes). All patients subsequently underwent PPV and silicone oil tamponade at our Institution. The first outcome measure was retinal reattachment, and second outcomes were reoperation rates, best-corrected visual acuity (BCVA) and postoperative complications. RESULTS: All patients in the SB group and 19 (90%) patients of the PPV group achieved retinal reattachment. Final BCVA was better in the SB group (p = 0.045). Two eyes in the PPV group required a third vitrectomy with heavy silicone oil tamponade. Postoperative complications included silicone oil in a deep anterior chamber (3 eyes in each group), untreatable hypotony in 1 eye in the PPV group (that led to enucleation due to phthisis bulbi), and elevated intraocular pressure in 3 patients (2 eyes in the PPV group). CONCLUSIONS: Phacoemulsification with IOL implant, PPV with silicone oil tamponade associated with 180° inferior retinotomy may lead to better anatomical success in patients who have previously undergone SB procedure for inferior retinal detachment repair compared with eyes that underwent a primary PPV.

[Familial exudative vitreoretinopathy].

Familial exudative vitreoretinopathy (FEVR) is a progressive hereditary retinal vascular disorder of unknown etiology. The disease is associated with gene mutation and mainly has an autosomal dominant mode of inheritance. Pathogenesis of the disease consists in abnormal retinal peripheral vasculogenesis. Three classifications, detailed clinical presentation and differential diagnostic criteria of the disease are presented. Surgical options of treatment of potential retinal detachment are discussed.

[Proliferative retinopathy, friend or foe?]. / Vitreoretinopatia proliferanta--prieten sau dusman?

Proliferative Vitreoretinopathy (PVR) refers to the migration and proliferation of cells into the subretinal space, vitreous cavity, and onto the retinal surface and undersurface. Subsequent collagen production and cell-mediated contraction of the collagenous scar leads to retinal detachment and loss of vision. Although refinements in surgical techniques and equipment have improved the success rate of surgery to repair retinal detachment in recent years, recurrence due to reproliferation is not uncommon and remains the leading cause of failure o retinal reattachment surgery.

Correlation of transforming growth factor ß-1 vitreous levels with clinical severity of proliferative vitreoretinopathy in patients with rhegmatogenous retinal detachment. / Correlación de niveles del factor de crecimiento transformante ß-1 con severidad de vitreorretinopatía proliferativa en pacientes con desprendimiento de retina regmatógeno.

OBJECTIVE: To correlate the vitreous concentration of transforming growth factor ß-1 (TGF ß-1) with the degree of clinical severity of proliferative vitreoretinopathy (PVR). DESIGN: A prospective, observational, cross-sectional study carried out on cases and controls. PARTICIPANTS: The study included 40 patients with a diagnosis of PVR secondary to rhegmatogenous retinal detachment. METHODS: Vitreous was obtained in patients undergoing pars plana vitrectomy by rhegmatogenous retinal detachment, who were treated during the period from August 2015 to June 2016, in a national reference centre for ophthalmological care in Mexico City, Mexico. The levels of TGFß-1 were quantified by ELISA technique. An ANOVA test was performed for the comparison of the different groups, together with a post-hoc Dunns test. A statistically significant difference was considered when obtaining P <.05. RESULTS: The levels of TGFß-1 were quantified, and the following means were found for each group: In the group with PVR grade A, 1150.6 ± 452.08 pg / ml, PVR grade B: 1129.6 ± 365.54 pg / ml, and PVR grade C: 1146.4 ± 330.21 pg / ml. The statistical analysis did not find significant differences when comparing the different PVR groups. (P=.53). However, when performing the differential analysis for each level of severity, a statistically significant increase in the expression of TGFß-1 was observed in the group of patients with PVR-A at a greater number of days of evolution of the detachment. (P=.03). There were no statistically significant differences for PVR-B and PVR-C (P=.16 and P=.16, respectively). CONCLUSION: Although the levels of TGFß-1 are not directly related to the clinical severity grade, suggesting that there must be other factors involved in the advanced stages of PVR, TGFß-1 may have greater relevance during the initial stages of the clinical course by promoting the epithelial-mesenchymal transition due to its greater expression in PVR-A. Thus, it can be concluded that each isoform plays a very particular role in the complex process of PVR.

A proposed new classification for diabetic retinopathy: the concept of primary and secondary vitreopathy.

BACKGROUND: Many eyes with proliferative diabetic retinopathy (PDR) require vitreous surgery despite complete regression of new vessels with pan retinal laser photocoagulation (PRP). Changes in the vitreous caused by diabetes mellitus and diabetic retinopathy may continue to progress independent of laser regressed status of retinopathy. Diabetic vitreopathy can be an independent manifestation of the disease process. AIM: To examine this concept by studying the long-term behavior of the vitreous in cases of PDR regressed with PRP. MATERIALS AND METHODS: Seventy-four eyes with pure PDR (without clinically evident vitreous traction) showing fundus fluorescein angiography (FFA) proven regression of new vessels following PRP were retrospectively studied out of a total of 1380 eyes photocoagulated between March 2001 and September 2006 for PDR of varying severity. Follow-up was available from one to four years. RESULTS: Twenty-three percent of eyes showing FFA-proven regression of new vessels with laser required to undergo surgery for indications produced by vitreous traction such as recurrent vitreous hemorrhage, tractional retinal detachment, secondary rhegmatogenous retinal detachment and tractional macular edema within one to four years. CONCLUSION: Vitreous changes continued to progress despite regression of PDR in many diabetics. We identifies this as "clinical diabetic vitreopathy" and propose an expanded classification for diabetic retinopathy to signify these changes and to redefine the indications for surgery.

Proliferative vitreoretinopathy: A new concept of disease pathogenesis and practical consequences.

During the last four decades, proliferative vitreoretinopathy (PVR) has defied the efforts of many researchers to prevent its occurrence or development. Thus, PVR is still the major complication following retinal detachment (RD) surgery and a bottle-neck for advances in cell therapy that require intraocular surgery. In this review we tried to combine basic and clinical knowledge, as an example of translational research, providing new and practical information for clinicians. PVR was defined as the proliferation of cells after RD. This idea was used for classifying PVR and also for designing experimental models used for testing many drugs, none of which were successful in humans. We summarize current information regarding the pathogenic events that follow any RD because this information may be the key for understanding and treating the earliest stages of PVR. A major focus is made on the intraretinal changes derived mainly from retinal glial cell reactivity. These responses can lead to intraretinal PVR, an entity that has not been clearly recognized. Inflammation is one of the major components of PVR, and we describe new genetic biomarkers that have the potential to predict its development. New treatment approaches are analyzed, especially those directed towards neuroprotection, which can also be useful for preventing visual loss after any RD. We also summarize the results of different surgical techniques and clinical information that is oriented toward the identification of high risk patients. Finally, we provide some recommendations for future classification of PVR and for designing comparable protocols for testing new drugs or techniques.

The prognostic utility of the Silicone Study Classification System. Silicone Study Report 9. Silicone Study Group.

OBJECTIVE: To evaluate the reproducibility and the prognostic utility of the Retina Society and Silicone Study Classification Systems in eyes after surgery for severe proliferative vitreoretinopathy (PVR). DESIGN: Subgroup analysis of the Silicone Study--a randomized, multicentered, surgical trial. SETTING: Community and university-based ophthalmology clinics. MATERIALS: Three hundred forty eyes with preoperative and intraoperative evaluations using both systems of grading PVR (reproducibility study), and 287 eyes with preoperative and intraoperative evaluations using both systems of grading PVR and with a 24-month follow-up examination (prognosis study). INTERVENTIONS: Vitrectomy for PVR with long-acting perfluoropropane gas or silicone oil as the intraocular tamponade. OUTCOME MEASURES: Retinal reattachment, visual acuity ( > or = 5/200), intraocular pressure, corneal clarity, and the need for reoperation. RESULTS: The reproducibility of the Silicone Study Classification System was 64% (type of contraction), 77% (number of clock hours), 67% (posterior PVR), 88% anterior and posterior PVR), and 94% (anterior, posterior, and subretinal PVR). The reproducibility of the Retina Society Classification System was 99%. Using the Silicone Study Classification System, location of PVR predicted visual acuity (P=.004, chi 2 test for trend) and hypotony (P=.03, chi 2 test for trend). Using the Retina Society Classification System, the grade of PVR predicted only visual acuity (P=.01, chi 2 test for trend). For eyes with anterior and posterior PVR, there was a decreasing trend in successful visual acuity outcome with increasing severity of PVR (from C-3 to D-3, P=.02, chi 2 test for trend). CONCLUSIONS: Although the classification of PVR using the Silicone Study classification System was not reproducible for the type of contraction or for posterior PVR, identification of the anteroposterior extent of the PVR was prognostic of visual acuity and hypotony at 24 months. The joint knowledge of the location of PVR (using the Silicone Study Classification System) and the tightness of the funnel for retinas with 9 to 12 clock hours involved by fixed folds (using the Retina Society Classification System) has prognostic utility for eyes with anterior and posterior PVR.

Macrophage migration inhibitory factor levels in the vitreous of patients with proliferative vitreoretinopathy.

PURPOSE: To assess the potential role of macrophage migration inhibitory factor (MIF) in the pathogenesis of proliferative vitreoretinopathy. METHODS: We assayed MIF levels in vitreous and paired serum samples of 74 consecutive patients with proliferative vitreoretinopathy (26 eyes), rhegmatogenous retinal detachment (22 eyes), and macular hole or idiopathic epiretinal membrane (control, 26 eyes) by enzyme-linked immunosorbent assay. RESULTS: Vitreous levels of MIF were 51.33 +/- 49.21 ng/ml (mean +/- SD) in proliferative vitreoretinopathy, 19.11 +/- 16.13 ng/ml in rhegmatogenous retinal detachment, and 2.98 +/- 2.55 ng/ml in the controls. The vitreous levels in eyes with proliferative vitreoretinopathy were significantly higher than levels in eyes with rhegmatogenous retinal detachment (P = .0005) and in the control subjects (P < .0001). The vitreous levels were significantly higher than the serum levels in proliferative vitreoretinopathy (P < .0001) and rhegmatogenous retinal detachment (P = .0019), respectively. CONCLUSIONS: The results suggest that MIF may be involved in the pathogenesis of proliferative vitreoretinopathy.

[Morphologic analysis of epiretinal membranes in surgically treated idiopathic macular foramina. Results of light and electron microscopy]. / Morphologische Analyse epiretinaler Membranen bei chirurgisch behandelten idiopathischen Makulaforamina. Licht-und elektronenmikroskopische Ergebnisse.

Anteroposterior and tangential traction on the central retina is an important factor in the pathogenesis of idiopathic macular hole formation. Histological studies have shown that macular holes of different stages can be associated with epiretinal membranes. Such membranes can be removed during surgery for macular holes. We investigated such tissue samples of 11 patients with macular holes in stages II-IV. Light microscopically, the tissue consisted of a thin collagen layer mostly covered by a thin layer of cells. Ultrastructural analysis revealed glial cells and macrophages as cellular components. The collagen can be ascribed to vitreous, inner limiting membrane and newly formed collagen. According to the morphological findings a multilayered tissue structure can be assumed. Macrophages were found on the retinal side of the inner limiting membrane and at the vitreal side of the tissue. Therefore, the macrophages probably originate from the retina as well as from the vitreous as so-called resident hyalocytes. Glial cells covered the inner limiting membrane forming pericellular collagen to which outer vitreous collagen fibrils can be attached. The multilayered membrane structure might possibly be the cause for only partial laminar surgical extraction so that contractile or potentially proliferative tissue residues might be one of the reasons for surgical failures after incomplete membrane peeling.

[Vitreoretinal proliferation. I. Clinicopathological aspects]. / La prolifération vitréorétinienne. I. Aspects clinicopathologiques.

Proliferative vitreoretinopathy (PVR) remains the major complication occurring after a rhegmatogenous retinal detachment, and often results in massive periretinal retraction which makes impossible any attempt in reattaching neuroepithelial layers. The most recently proposed classifications of PVR as well as clinical observations improved the understanding of PVR and suggested that some events could be of striking importance in its development, such as the size of retinal breaks, eventual haemorrhages or overdosed cryoapplications. Most interesting findings, however, resulted from the more and more powerful analysis of vitreoretinal membranes. Electron microscopy, immunohistochemistry and molecular biology techniques permitted identification of a wide variety of cellular and biological components. The majority of cells involved in PVR are from retinal or ciliary pigment epithelial, glial or inflammatory origins. Extracellular matrix are constituted with collagen, fibronectin, heparan sulfates or laminin, but they also contain growth factors, immunoglobulins and activated complement. Moreover, proliferating cells express membrane receptors to growth factors and to immunocompetent cells, which makes PVR an extraordinarily complicated biological syndrome, involving a wide range of mediators and cellular systems.

[The sub-classification and long-term prognosis of preproliferative diabetic retinopathy].

PURPOSE: We followed eyes with preproliferative diabetic retinopathy(PPDR) for 2 or more years, and then evaluated the proportion of patients developing proliferative diabetic retinopathy(PDR) and the period from diagnosis of PPDR until development of PDR. SUBJECTS AND METHODS: We divided 95 eyes affected by PPDR into 75 eyes with mild type and 20 eyes with moderate type based on our previously proposed sub-classification, and evaluated the long-term prognosis of 2 or more. RESULTS: The proportion developing PDR was 24% in mild type and 60% in moderate type. The average period from diagnosis of PPDR until development of PDR was 6 years and 5 months in the mild type and 2 years in the moderate type. The accumulative occurrence rates of PDR at two, 5, and 10 years were estimated to be 0%, 14%, and 39% in the mild type and 35%, 58%, and 79% in the moderate type, respectively. The proportion developing PDR was significantly higher and the average period until PDR development significantly shorter in the moderate than in the mild type. In mild type eyes, the rate of progression to moderate type was 56% and further progression from moderate type to PDR was noted in 43%. CONCLUSION: The above results again verify the usefulness of our sub-classification, and also provide useful information about the long-term prognosis of PPDR.

[Surgical therapeutic results of rhegmatogenous retinal detachment associated with choroidal detachment].

OBJECTIVE: To evaluate the effect of different factors on the prognosis of rhegmatogenous retinal detachment (RRD) associated with choroidal detachment (ChD). METHODS: One hundred and eighty-eight eyes of 188 patients were studied retrospectively from Jan, 1996 to Aug, 1998. The clinical data, surgical management and follow-up records were analyzed. RESULTS: The total successful rate of the surgery was 83.0%, lower than that of general RRD. In the eyes with proliferative vitreoretinopathy (PVR) A-B, the rate was 89.6%, in the eyes with C(1)-C(3) PVR, the rate was 84.1%, in D(1)-D(3), 69.0%. In eyes with severe PVR the successful rate of vitrectomy was higher than that of scleral buckling alone. Administration of steroids before surgery resulted in high successful rate, but the length of time of the steroid treatment had no effect on the successful rate. In the eyes using scleral buckling alone, the drainage or without the drainage of subretinal fluid had no effect on the successful rate. CONCLUSIONS: RRD associated with ChD has worse prognosis than general RRD. The administration of steroids before surgery is necessary, and the timing of surgery is also important. In eyes with light PVR and ChD, scleral buckling without drainage of subretinal fluid is the first choice, but in eyes with severe PVR and ChD, vitrectomy is a better choice.

[Proliferative vitreoretinopathy]. / Vitreoretinopatia proliferativa.

The most common cause for ultimate failure after retinal reattachment surgery is the development of VRP. I briefly review the pathology, the pathogenesis and classification of PVR, the surgical management and complication of vitreous surgery and possible future advances in the management of PVR.

[Proliferative vitreoretinopathy: pathophysiology and clinical diagnosis]. / Prolifération vitréo-rétinienne : physiopathologie et diagnostic clinique.

Proliferative vitreoretinopathy (PVR) remains one of the most common causes of failed retinal detachment (RD) surgery. Many histological and clinical studies have highlighted the chain of events leading to PVR: cellular migration into the vitreous cavity, cellular differentiation, myofibroblast proliferation and activation, synthesis of extracellular matrix proteins, then contraction of preretinal tissues. The development of PVR can be explained schematically by cellular exposure to growth factors and cytokines (particularly retinal pigment epithelial cells and glial cells), in the context of break-down of the blood-retinal barrier (inflammation, choroidal detachment, iatrogenic effect of cryotherapy and surgery) and of cellular contact with the vitreous. Although the pathophysiology of PVR is now better understood, its severity remains an issue. A systematic search for preoperative PVR risk factors allows the most suitable therapeutic option to be chosen.

Pathogenesis and classification of proliferative diabetic vitreoretinopathy.

PURPOSE: To review the current knowledge regarding the pathogenesis of proliferative diabetic vitreoretinopathy (PDVR) and to present recommendations for its clinical staging. DESIGN: Focused literature review and authors' clinical experience. RESULTS: Although several biochemical mediators may be responsible for the pathogenesis of PDVR, no common biochemical pathway exists. Of those mediators, vascular endothelial growth factor is the one most studied so far. However, since in proliferative diabetic retinopathy (PDR) the thickened posterior vitreous cortex is one of the main factors in the development of proliferations, a consequent shrinkage of the posterior vitreous cortex leads to hemorrhages and tractive retinal detachments. Therefore, PDR should be called PDVR. In consequence, the authors present a new morphological classification of PDVR. CONCLUSIONS: There is no consensus about the biochemical pathway responsible for the progression of PDVR. Although several classifications are described in the literature, the classification suggested here is important in the judgment of, the communication about and the therapy of diabetic retinopathy. Furthermore, it is the only reliable classification for predicting the surgical outcome in diabetics.

Clinical risk factors for proliferative vitreoretinopathy after retinal detachment surgery.

PURPOSE: To identify the clinical risk factors for the development of severe proliferative vitreoretinopathy (PVR) after retinal detachment surgery. METHODS: A retrospective study of 1020 patients with either no PVR or with PVR of grade C1 or less at initial examination was conducted. After surgery, severe PVR was defined as grade C2 or worse. The data relating to 94 variables were evaluated by univariate analysis and stepwise logistic regression. RESULTS: Severe PVR developed after surgery in 107 patients (10.5%). Ten significant predictive variables were identified: minor intra- or postoperative hemorrhage, grade A preoperative PVR, preoperative choroidal detachment, giant tears, air tamponade, detachment involving more than 2 quadrants, cumulative break area larger than 3 optic disks, postoperative choroidal detachment, signs of uveitis at initial examination, and grade B preoperative PVR. CONCLUSION: The results indicate that in addition to the size of breaks, extent of detachment, and presence of preoperative inflammation or low-grade PVR, iatrogenic problems also are important factors in the pathogenesis of severe PVR after surgery for retinal detachment.