Electrolyte composition of retro-oil fluid and silicone oil-related visual loss.

PURPOSE: Up to one-third of patients with intra-ocular silicone oil (SO) tamponade for complex macula-on retinal detachment may experience an unexplained visual loss during or after SO tamponade. Although the underlying mechanism is unknown, previous studies suggested that accumulation of retinal potassium could be involved. Hence, this study tested the hypothesis that intra-ocular potassium levels are elevated during SO tamponade. METHODS: A prospective cohort study was carried out from 13 October 2013 through 5 March 2015. Potassium, sodium, magnesium, chloride, calcium, lactate dehydrogenase (LDH) and glucose levels were measured in retro-oil fluid and paired serum from 16 patients undergoing oil removal, including two patients with SO-related visual loss (SORVL). Vitreous humour and paired serum from 27 patients with macular hole (n = 19) or floaters (n = 8) served as controls. RESULTS: Median potassium levels in retro-oil fluid and vitreous humour were similar. Magnesium and chloride levels were lower in retro-oil fluid compared with vitreous humour (p < 0.01) and LDH levels were elevated in retro-oil fluid (p < 0.0001). One of the two patients with SORVL revealed abnormal high potassium and magnesium levels. The other patient had normal levels. CONCLUSION: Potassium levels are not increased in retro-oil fluid during SO tamponade, making the 'potassium accumulation' hypothesis unlikely. The disturbance in magnesium concentration during SO tamponade warrants further investigation.

Diplopia was not predictable and not associated with buckle position after scleral buckling surgery for retinal detachment.

PURPOSE: The possibility of postoperative binocular diplopia is seen as an important drawback of conventional scleral buckling surgery for rhegmatogenous retinal detachment. The goal of this study was to evaluate the occurrence and pattern of binocular diplopia after scleral buckle procedures in patients with rhegmatogenous retinal detachment. METHODS: In a retrospective study of 1,030 patients with primary rhegmatogenous retinal detachment who were treated by scleral buckle surgery between January 2001 and July 2008, the postoperative occurrence of binocular diplopia was retrieved from the medical charts. RESULTS: Secondary strabismus developed in 39 subjects (3.8%) after scleral buckle surgery during a mean follow-up of 6.4 ± 6.3 months. Twenty-eight patients (2.7%) developed strabismus because of a mechanical restriction of one of the muscles. No association was found between the position of the buckle, that is, the muscle affected, and the incidence of diplopia. A moderate significant association was found when two muscles were affected with a higher incidence of diplopia. This was, however, not found for three or more muscles. In 28 of 39 patients, binocular single vision was restored at the end of the follow-up period. In the majority, this was accomplished with conventional prism treatment. CONCLUSION: Strabismus caused by a restriction of the muscles in scleral buckle surgery was not predictable based upon the buckle position. Patients with a minimal restriction of the muscles after scleral buckle surgery can often be well treated with prisms.

Interleukin and growth factor levels in subretinal fluid in rhegmatogenous retinal detachment: a case-control study.

BACKGROUND: Rhegmatogenous retinal detachment (RRD) is a major cause of visual loss in developed countries. Proliferative vitreoretinopathy (PVR), an eye-sight threatening complication of RRD surgery, resembles a wound-healing process with inflammation, scar tissue formation, and membrane contraction. This study was performed to determine the possible involvement of a wide range of cytokines in the future development of PVR, and to identify predictors of PVR and visual outcome. METHODOLOGY: A multiplex immunoassay was used for the simultaneous detection of 29 different cytokines in subretinal fluid samples from patients with primary RRD. Of 306 samples that were collected and stored in our BioBank between 2001 and 2008, 21 samples from patients who developed postoperative PVR were compared with 54 age-, sex-, and storage-time-matched RRD control patients who had an uncomplicated postoperative course during the overall follow-up period. FINDINGS: Levels of IL-1α, IL-2, IL-3, IL-6, VEGF, and ICAM-1 were significantly higher (P<0.05) in patients who developed postoperative PVR after reattachment surgery than in patients with an uncomplicated postoperative course, whereas levels of IL-1ß, IL-4, IL-5, IL-7, IL-9, IL-10, IL-11, IL-12p70, IL-13, IL-15, IL-17, IL-18, IL-21, IL-22, IL-23, IL-25, IL-33, TNF-α, IFN-γ, IGF-1, bFGF, HGF, and NGF were not (P>0.05). Multivariate logistic regression analysis revealed that IL-3 (P = 0.001), IL-6 (P = 0.047), ICAM-1 (P = 0.010), and preoperative visual acuity (P = 0.026) were independent predictors of postoperative PVR. Linear regression analysis showed that ICAM-1 (P = 0.005) and preoperative logMAR visual acuity (P = 0.001) were predictive of final visual outcome after primary RRD repair. CONCLUSIONS/SIGNIFICANCE: Our findings indicate that after RRD onset an exaggerated response of certain cytokines may predispose to PVR. Sampling at a time close to the onset of primary RRD may thus provide clues as to which biological events may initiate the development of PVR and, most importantly, may provide a means for therapeutic control.

Persistent subfoveal fluid and increased preoperative foveal thickness impair visual outcome after macula-off retinal detachment repair.

PURPOSE: To investigate the influence of subfoveal fluid and foveal thickness on visual outcome in patients who underwent reattachment surgery for rhegmatogenous retinal detachment (RRD). METHODS: This prospective study included 53 patients who were undergoing successful scleral buckling surgery for primary RRD. A thorough ophthalmologic examination including best-corrected visual acuity, slit-lamp biomicroscopy, binocular indirect ophthalmoscopy, and optical coherence tomography scanning was performed preoperatively and during all subsequent follow-up visits at 1, 3, 6, 9, 12, and 24 months postoperatively. RESULTS: Preoperative foveal thickness was significantly higher in the macula-off group (n = 38) compared with the macula-on group (n = 15) (P < 0.0001), whereas postoperative measurements were normal in both the groups. Linear mixed-model analysis revealed that persistent subfoveal fluid (P = 0.0004) was an independent predictor of a worse visual outcome after scleral buckling surgery for primary macula-off RRD, although the effect on visual outcome was small (0.1 logarithm of the minimal angle of resolution units). Moreover, increased preoperative foveal thickness was associated with a worse visual prognosis in macula-off RRD (P = 0.010). CONCLUSION: Persistent subfoveal fluid and increased preoperative foveal thickness were associated with a worse visual prognosis in macula-off RRD patients, albeit the effect of persistent subfoveal fluid was small and temporary.

High subretinal fluid procoagulant activity in rhegmatogenous retinal detachment.

PURPOSE: An increased mRNA expression of genes related to blood coagulation has been demonstrated in an experimental retinal detachment model but has not yet been confirmed in human clinical specimens. Tissue factor (TF), the initiating factor of blood coagulation, may be a determinant of the extent of tissue injury after rhegmatogenous retinal detachment (RRD). This study was conducted to determine whether subretinal fluid and vitreous fluid collected from patients with RRD have a procoagulant effect. METHODS: Calibrated thrombin generation (CAT) was used to investigate the thrombogenic properties of 28 subretinal fluids collected during scleral buckling surgery for RRD. Further, the thrombogenic properties of vitreous fluids from RRD (n = 12), macular pucker (n = 5), macular hole (n = 6), and proliferative diabetic retinopathy (n = 5) were compared with the properties of eye bank eyes (n = 11), which served as control specimens. The procoagulant activity of TF was determined with Western blot analysis. RESULTS: The addition of subretinal fluid from all RRD patients (28/28, 100%) induced thrombin generation in normal and severely factor (F)XII-deficient plasma. Contrary to the subretinal fluid, the addition of vitreous fluids from various ocular disorders evoked very little thrombin generation in normal and severely FXII-deficient plasma (4/12, 33% RRD; 1/5, 20% macular pucker; 0/6, 0% macular hole; 0/5, 0% proliferative diabetic retinopathy; and 2/11, 18% eye bank eyes). The procoagulant activity in subretinal fluid was almost completely neutralized by antibodies against human TF. The presence of TF in subretinal fluid was confirmed by Western blot. CONCLUSIONS: Subretinal fluid of patients with RRD induces high procoagulant activity, determined by measuring the level of tissue factor.

Chemokine levels in subretinal fluid obtained during scleral buckling surgery after rhegmatogenous retinal detachment.

PURPOSE: Interleukin (IL)-6, a multifunctional cytokine with regulatory functions in wound healing, and several chemokines have been implicated in the pathogenesis of proliferative vitreoretinopathy (PVR) after rhegmatogenous retinal detachment (RRD). The exact role of these chemokines, their correlation with IL-6 after primary RRD, and their association with the future development of PVR are not yet known. METHODS: A multiplex immunoassay was used to determine levels of 15 different chemokines and IL-6 in subretinal fluid samples obtained during scleral buckling surgery for primary RRD. Samples from patients with preoperative uveitis, preoperative trauma, or preoperative vitreous hemorrhage were excluded. Patients who developed a redetachment due to postsurgical PVR within 2.5 months (n = 21) were compared with control subjects who had an uncomplicated retinal detachment during the overall follow-up period (n = 54). Control subjects were matched for sex, age, and storage time. RESULTS: Levels of IL-6 (P = 0.001), MIF (P = 0.016), CCL2 (P = 0.041), CCL11 (P = 0.012), CCL17 (P = 0.003), CCL18 (P = 0.007), CCL19 (P < 0.001), CCL22 (P < 0.001), CXCL8 (P = 0.027), CXCL9 (P = 0.007), and CXCL10 (P = 0.002) were significantly higher in patients who developed postoperative PVR after primary RRD than in patients with uncomplicated retinal detachment. A significant positive correlation was observed between IL-6 and both CCL22 (r = 0.538; P < 0.0001) and CXCL8 (r = 0.645; P < 0.0001). CONCLUSIONS: Various chemokines and IL-6 are upregulated in patients in whom fibrotic membranes develop after primary RRD repair and may therefore be involved in the future development of postoperative PVR.

Anterior chamber depth is significantly decreased after scleral buckling surgery.

OBJECTIVE: Myopic patients have an increased risk for the development of a rhegmatogenous retinal detachment (RRD). Currently, myopic patients have the choice to undergo correction of their refractive error by the implantation of a phakic intraocular lens (pIOL). After pIOL implantation, progressive endothelial cell loss may result if the anterior chamber is too shallow. Because scleral buckling (SB) surgery for treatment of an RRD may in itself result in a decreased anterior chamber depth (ACD), this may become an important issue not only for the retinal surgeon who is faced with a patient who has both an RRD and a pIOL, but also for the refractive surgeon who should consider the potential problems of the implantation of pIOL in an eye that has previously undergone SB surgery. The goal of this study was to evaluate how long changes in ACD persist after SB procedures in patients with RRD. DESIGN: Prospective case series. PARTICIPANTS: Thirty-eight eyes with a primary RRD treated by SB using an encircling element and a radial or segmental buckle; 31 fellow eyes served as controls. METHODS: Anterior chamber depth (in the horizontal meridian) and axial length were measured preoperatively and at 1 week and 1, 3, 6, 9, and 12 months postoperatively with an anterior optical coherence tomography method and an IOLMaster (Carl Zeiss Meditec, Jena, Germany), respectively. MAIN OUTCOME MEASURES: In all 38 eyes, ACD was significantly reduced compared with preoperative levels up to 9 months after SB surgery. RESULTS: Anterior chamber depth returned to normal at 1 year after surgery. Axial length was significantly enlarged during the whole follow-up period. No significant differences were found between the use of radial or segmental buckles. CONCLUSIONS: Anterior chamber depth may remain decreased after SB for a longer time period than previously reported. FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any materials discussed in this article.

Incidence of redetachment 6 months after scleral buckling surgery.

PURPOSE: The preoperative and intraoperative clinical variables associated with redetachment and/or a poor visual outcome following scleral buckling (SB) surgery for rhegmatogenous retinal detachment (RRD) have mainly been studied after a short follow-up. This study aimed to analyse long-term effects by following patients for at least 6 months. METHODS: In a retrospective survey we evaluated the data of 436 eyes that underwent SB surgery. Postoperative data were collected at 3-month intervals. RESULTS: After a mean follow-up period of 51 months, anatomic reattachment was achieved in 76% after one SB procedure, with a final reattachment rate of 97% after additional vitreoretinal procedures. In total, 104 eyes developed redetachment during follow-up. After more than 6 and 12 months of follow-up, 32 eyes (7%) and 20 eyes (5%), respectively, developed redetachment. Multivariate regression analysis showed that recurrent redetachment and more than 7 days of visual field loss were significant predictors for a poor postoperative visual outcome at 12 months. A cumulative size of the tear of more than three disc diameters was a significant predictor of recurrent RRD. CONCLUSION: Conventional SB surgery is a reliable procedure in a selected group of eyes with primary RRD. However, in eyes with a retinal tear with a cumulative size of more than three disc diameters, a primary vitrectomy should be considered. Taking into account that 7% of eyes developed redetachment after 6 months, a longer follow-up period seems necessary to evaluate the anatomical and visual outcomes after SB surgery.

Low redetachment rate due to encircling scleral buckle in giant retinal tears treated with vitrectomy and silicone oil.

BACKGROUND: The goal of this study was to identify risk factors for redetachment and to assess long-term anatomic and functional results of pars plana vitrectomy (PPV) for retinal detachment associated with giant retinal tears (GRT). SUBJECTS AND METHODS: In a retrospective study the authors analyzed 30 eyes which were operated with PPV for GRT retinal detachment in their clinic between March 1998 and August 2003. RESULTS: Redetachment rate after one vitrectomy procedure in this series of 30 eyes was 30% (n = 9), and ultimately, the retina was attached in 29 (96.7%) eyes. After multivariate analysis the absence of an encircling scleral buckle (P = 0.008) was significantly associated with redetachment. Visual acuity improved in 54% of the eyes. CONCLUSION: Vitrectomy with an encircling scleral buckle seems to be a preferred treatment for complicated retinal detachments due to GRT.

Balance of vascular endothelial growth factor and pigment epithelial growth factor prior to development of proliferative vitreoretinopathy.

BACKGROUND: Pigment epithelium-derived factor (PEDF) and vascular endothelial growth factor (VEGF) are imbalanced in eyes with proliferative diabetic retinopathy or proliferative vitreoretinopathy (PVR). It is not known whether such an imbalance is already present in early PVR stages. We therefore analyzed VEGF and PEDF concentrations in subretinal fluids prior to PVR development. METHODS: A large number (n = 137) of subretinal fluid samples were obtained at the time of scleral buckling surgery for rhegmatogenous retinal detachment (RRD). Thirty patients developed PVR within 6 months after surgery. One hundred and seven patients undergoing the same surgery but without complications served as controls. Furthermore, vitreous from 16 patients with macular hole or pucker (MHP) served as reference for baseline intraocular concentrations. PEDF and VEGF concentrations were measured by commercial ELISAs. RESULTS: PEDF levels were substantially higher (9.6 microg/ml) compared to MHP vitreous (0.3 microg/ml, p < 0.001). VEGF levels were also higher (RRD: 0.07 ng/ml; MHP: 0.01 ng/ml, p < 0.05). Subretinal concentrations were not significantly different between PVR and control RRD patients. CONCLUSIONS: Although both VEGF and PEDF are increased at first surgery for RRD, they do not predict PVR development later on. The high PEDF concentrations and its known antiangiogenic activity suggest a protective role against neovascularization.

Scleral buckling surgery after macula-off retinal detachment: worse visual outcome after more than 6 days.

PURPOSE: To determine the effect of duration of macular detachment (DMD) on visual acuity (VA) in patients with macula-off rhegmatogenous retinal detachment (RD). DESIGN: Retrospective observational case series. PARTICIPANTS: Two hundred two consecutive patients (202 eyes) with primary uncomplicated macula-off RD, preoperative VA of 10/100 or worse, a precise history of when macular function was lost, successful reattachment surgery, and a minimal follow-up of 3 months. INTERVENTION: All RDs were repaired with a primary scleral buckling procedure performed by 3 vitreoretinal surgeons. MAIN OUTCOME MEASURE: Visual acuity (best corrected and 3, 6, and 12 months postoperatively). RESULTS: Considering all eyes, the cumulative mean of the best-corrected postoperative VA (logarithm of the minimum angle of resolution [logMAR]) as a function of DMD shows a rapid worsening when DMD exceeds 6 days. Eyes were divided into 3 groups, corresponding to the DMD intervals immediate (within 10 days), delayed (11 days-6 weeks), and late (>6 weeks). Mean postoperative VAs (in logMAR) were 0.35+/-0.31 (between 20/40 and 20/50 Snellen equivalent) in eyes with DMD up to 10 days, 0.48+/-0.26 (20/60 Snellen equivalent) in the delayed group, and 0.86+/-0.30 (8/60 Snellen equivalent) in eyes with DMD longer than 6 weeks. CONCLUSIONS: The cumulative mean of the best-corrected postoperative VA (logMAR) as a function of DMD shows a rapid worsening when DMD exceeds 6 days. Our results indicate that the scleral buckling procedure should be done preferably within a 7-day DMD.

Intravitreal prednisolone sodium succinate reduces diabetic macular edema without intraocular pressure rise.

PURPOSE: To evaluate the six-month results of patients treated with intravitreal prednisolone sodium succinate injections for persistent diabetic macular edema. DESIGN: Retrospective, noncontrolled, clinical case series. METHODS: Nineteen eyes had intravitreal injections with prednisolone sodium succinate. Need for retreatment was based on fluorescein angiographic or optical coherence tomography evidence of persisting macular edema. RESULTS: Mean visual acuity at six weeks, three months, and six months after injection was significantly better than the mean preoperative visual acuity (P = .015, P = .004, and P = .031, respectively). In none of the studied eyes intraocular pressure exceeded 22 mm Hg. No other adverse events, such as endophthalmitis or retinal detachment, occurred. CONCLUSIONS: In this small pilot study, mean visual acuity improvement was statistically significant up to six months postoperatively. Current results suggest that intravitreal injection of the solution of prednisolone sodium succinate may be a safe and good alternative in eyes with macular edema.

Increased glutamate levels in the vitreous of patients with retinal detachment.

Experimental models have implicated glutamate in the irreversible damage to retinal cells following retinal detachment. In this retrospective study we investigated a possible role for glutamate and other amino acid neurotransmitters during clinical rhegmatogenous retinal detachment (RRD). Undiluted vitreous samples were obtained from 176 patients undergoing pars plana vitrectomy. The study group consisted of 114 patients (114 eyes) with a rhegmatogenous retinal detachment. Controls included 52 eyes with an idiopathic macular hole or idiopathic epiretinal membrane and 10 eyes with a traction retinal detachment due to proliferative diabetic retinopathy. Vitreous concentrations of glutamate, gamma-aminobutyric acid (GABA), taurine, glycine, and aspartate were determined by high-pressure liquid chromatography (HPLC). Multivariate analysis was used to examine a possible association between amino acid neurotransmitter levels and several clinical variables including visual acuity. The mean vitreous concentration of glutamate in eyes with a rhegmatogenous retinal detachment (16.6 +/- 5.6 microM) was significantly higher as compared to the controls (13.1 +/- 5.2 microM) (P = 0.001). Taurine levels were also increased in RRD, whereas no significant difference could be observed in glycine, aspartate and GABA levels when comparing RRD with controls. A correlation was found between increased vitreous glutamate and a lower pre-operative visual acuity. No association was, however, observed between post-operative visual acuity and the level of any of the five amino acid neurotransmitters. RRD was associated with a significantly increased vitreous glutamate concentration. Using visual acuity as a functional parameter in this study, we could not demonstrate a correlation between vitreous glutamate, or any of the other tested amino acid neurotransmitters and visual outcome.

Immunohistochemical analysis of the internal limiting membrane peeled with infracyanine green.

PURPOSE: To investigate whether the peeled internal limiting membrane (ILM) contains cellular retinal cell fragments, and to learn more about their possible origin. DESIGN: Experimental study. METHODS: ILM peeled from ten eyes during vitrectomy by infracyanine green (ICG) was studied immunohistochemically using the markers: GFAP, S-100, and vimentin. Five ILM specimens were from eyes with diabetic macular edema (DME), two from eyes with a macular hole, and three from eyes with persisting macular edema after retinal detachment surgery. RESULTS: In eight of the ten ILM specimens, we found GFAP-positive staining, indicating the presence of remnants of footplates from Müller cells or glial cells. Two ILM specimens were positive for S-100, indicating the presence of neural cells or ganglion cells. CONCLUSIONS: ILM peeled from the retina during vitrectomy using ICG may contain remnants of Müller cell footplates, neural cells, and ganglion cells.

High TGF-beta2 levels during primary retinal detachment may protect against proliferative vitreoretinopathy.

PURPOSE: Transforming growth factor (TGF)-beta2 and hepatocyte growth factor (HGF) have been implicated in the pathogenesis of proliferative vitreoretinopathy (PVR) after retinal detachment surgery. The exact role of these factors in the early events, immediately after primary retinal detachment, is not yet known, and determining their roles was therefore the purpose of this study. METHODS: Subretinal fluids were collected prospectively from 144 patients during surgery for scleral buckling. TGF-beta2 and HGF were measured with commercially available ELISA kits. Thirty patients in whom a redetachment caused by postoperative PVR developed, were compared with 114 patients with an uncomplicated retinal detachment. The controls included 18 vitreous samples from patients with macular hole or pucker. Multivariate regression analysis was used to compare the relative roles of growth factors and clinical factors in the development of PVR. RESULTS: The median amount of subretinal TGF-beta2 was approximately two times lower in patients with postoperative PVR (1.9 ng/mL) than in the uncomplicated detachment group (3.3 ng/mL; P=0.002). TGF-beta2 levels in the PVR-positive group were similar to control vitreous levels (1.8 ng/mL). Subretinal HGF concentrations were not significantly different between the two groups of patients (PVR positive: 8.8 ng/mL; PVR negative: 8.9 ng/mL), but were higher than control vitreous levels (4.6 ng/mL; P=0.01). Stepwise multivariate logistic regression analysis revealed that of all factors under study, decreased TGF-beta2 content was the exclusive predictor of postoperative PVR (P=0.01). CONCLUSIONS: High TGF-beta2 levels in subretinal fluid at the time of primary retinal detachment may protect a patient against subsequent development of PVR.

Clinical variables and their relation to visual outcome after vitrectomy in eyes with diabetic retinal traction detachment.

BACKGROUND: To analyse vitrectomy results in diabetic eyes with retinal traction detachment and to investigate which variables are associated with a worse visual outcome. METHODS: Forty-four diabetic eyes (33 patients) with central retinal traction detachment were analyzed retrospectively. RESULTS: After a median follow-up of 10 months, median visual acuity significantly improved from 20/800 to 20/160 (P=0.02), despite the fact that the majority of patients had a long-standing macular traction detachment (median 120 days). Twenty-two eyes (50%) achieved a visual acuity of >20/200. The retina was finally reattached in 38 eyes (86.3%). Univariate analysis showed that patients with type 2 diabetes, age older than 50 years, preoperative visual acuity <20/200, iris neovascularisation and macular detachment of >30 days had a significantly worse final visual outcome. After multiple logistic regression analysis, age and iris neovascularisation were the strongest predictors of a worse visual outcome; if both were present, the chance of a obtaining a visual outcome of <20/200 was almost 90%. CONCLUSIONS: Age and iris neovascularisation were the strongest predictors for a low visual outcome. In a review of vitrectomy studies in eyes with severe diabetic traction detachment in the past 2 decades, we found a trend towards higher anatomic success rates, while visual outcome only slightly improved. The current study confirmed the importance of ophthalmic variables, but also indicates the importance of evaluating systemic variables in larger series in order to predict which eyes may truly benefit from vitrectomy.

Basic fibroblast growth factor, glutamine synthetase, and interleukin-6 in vitreous fluid from eyes with retinal detachment complicated by proliferative vitreoretinopathy.

PURPOSE: To investigate the presence of basic fibroblast growth factor (bFGF), glutamine synthetase (GS), and interleukin-6 (IL-6) in vitreous fluid from eyes with retinal detachment complicated by proliferative vitreoretinopathy (PVR). DESIGN: Comparative case series; experimental study. METHODS: In a prospective study, we measured bFGF, GS, IL-6, and total protein in vitreous fluid samples from 53 eyes from 53 consecutive patients with PVR operated on in our hospital. As controls, vitreous fluid samples from eyes with a macular hole (n = 9) or pucker (n = 11) were used. MAIN OUTCOME MEASURES: Laboratory data of the patient group were compared with the control group and correlated with various clinical data, especially with visual recovery and redetachment. RESULTS: For IL-6, bFGF, and total protein we found significantly higher levels in PVR patients' eyes than in control eyes (P =.03, P =.046, and P <.0001, respectively). Within the PVR group, no significant correlation was found for IL-6, bFGF, GS, or total protein with the various tested clinical variables. CONCLUSIONS: We found increased levels of IL-6, bFGF, and total protein in vitreous fluid from patients' eyes with PVR. Whether the increased levels of IL-6, bFGF, and total protein are the result of an injury-induced upregulation of these proteins as part of a self-protective mechanism of the retina to minimize photoreceptor damage after the mechanical injury induced by retinal detachment is, at present, not known.