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Papers by Sarit Oberstein

American Journal of Ophthalmology

The British journal of ophthalmology

Journal of cell communication and signaling, 2013

In proliferative diabetic retinopathy (PDR), vascular endothelial growth factor (VEGF) and CCN2 (... more In proliferative diabetic retinopathy (PDR), vascular endothelial growth factor (VEGF) and CCN2 (connective tissue growth factor; CTGF) cause blindness by neovascularization and subsequent fibrosis. This angio-fibrotic switch is associated with a shift in the balance between vitreous levels of CCN2 and VEGF in the eye. Here, we investigated the possible involvement of other important mediators of fibrosis, tissue inhibitor of metalloproteinases (TIMP)-1 and transforming growth factor (TGF)-β2, and of the matrix metalloproteinases (MMP)-2 and MMP-9, in the natural course of PDR. TIMP-1, activated TGF-β2, CCN2 and VEGF levels were measured by ELISA in 78 vitreous samples of patients with PDR (n = 28), diabetic patients without PDR (n = 24), and patients with the diabetes-unrelated retinal conditions macular hole (n = 10) or macular pucker (n = 16), and were related to MMP-2 and MMP-9 activity on zymograms and to clinical data, including degree of intra-ocular neovascularization and fi...

Molecular vision, 2011

To quantify the extent of cellular proliferation and immunohistochemically characterize the proli... more To quantify the extent of cellular proliferation and immunohistochemically characterize the proliferating cell types in epiretinal membranes (ERMS) from four different conditions: proliferative vitreoretinopathy (PVR), proliferative diabetic retinopathy, post-retinal detachment, and idiopathic ERM. Forty-six ERMs were removed from patients undergoing vitrectomy and immediately fixed in paraformaldehyde. The membranes were processed whole and immunolabeled with either anti-MIB-1 or anti-SP6 to detect the K(i)-67 protein in proliferating cells, in combination with anti-glial fibrillary acidic protein or anti-vimentin to identify glia, anti-ezrin to identify retinal pigment epithelial cells, Ricinus communis to identify immune cells, and Hoechst to label nuclei. Digital images were collected using a laser scanning confocal microscope. The cell types were identified, their combined proliferative indices were tabulated as the average number of anti-K(i)-67-positive cells/mm(2) of tissue,...

Retina, 2012

To describe fundus autofluorescence and optical coherence tomography (OCT) features of the macula... more To describe fundus autofluorescence and optical coherence tomography (OCT) features of the macula after pars plana vitrectomy for rhegmatogenous retinal detachment. Thirty-three eyes of 33 consecutive patients with repaired rhegmatogenous retinal detachment with or without the involvement of the macula were prospectively investigated with simultaneous fundus autofluorescence and OCT imaging using the Spectralis HRA+OCT (Heidelberg Engineering, Heidelberg, Germany) within a few weeks after the operation. Fundus autofluorescence imaging of the macula showed lines of increased and decreased autofluorescence in 19 cases (57.6%). On OCT, these lines corresponded to the following abnormalities: outer retinal folds, inner retinal folds, and skip reflectivity abnormalities of the photoreceptor inner segment/outer segment band. Other OCT findings, not related to abnormal lines on fundus autofluorescence, consisted of disruption of photoreceptor inner segment/outer segment band and collection of intraretinal or subretinal fluid. The presence of outer retinal folds significantly related to metamorphopsia but did not relate to poor postoperative visual acuity. Partial-thickness retinal folds occur commonly after vitrectomy for rhegmatogenous retinal detachment repair and may represent an important anatomical substrate for postoperative metamorphopsia. Fundus autofluorescence and OCT are both sensitive techniques for the detection of these abnormalities.

Retina, 2012

To describe the incidence and outcome of retinal breaks in vitrectomy for retained lens fragments... more To describe the incidence and outcome of retinal breaks in vitrectomy for retained lens fragments. This is a retrospective noncomparative interventional case series. Medical records of consecutive cases of vitrectomy for retained lens fragments over a period of 4 years were reviewed. Main outcome measures were incidence of breaks, visual acuity outcome, and occurrence of postoperative complications. We included 89 consecutive cases in 89 patients. The median interval between cataract surgery and vitrectomy was 2 days (range, 0-106 days). Visual acuity at last follow-up was ≥ 0.5 in 70% of cases. During surgery, retinal breaks were found in 29% of cases. Induction of a posterior vitreous detachment, the use of a fragmatome, or delay between cataract surgery and vitrectomy did not influence retinal break incidence. Postoperative retinal detachment occurred in only 2% of cases. Other complications were intraoperative choroidal hemorrhage in 1 case, postoperative macular pucker in 2, postoperative macular edema in 1, and glaucoma in 2 cases. We identified a high number of retinal breaks during vitrectomy for retained lens fragments. Prophylactic treatment of breaks and other areas of retinal traction seem to reduce the risk of postoperative retinal detachment.

Investigative Ophthalmology & Visual Science, 2012

To assess the evolution of outer retinal folds (ORFs) occurring after repair of rhegmatogenous re... more To assess the evolution of outer retinal folds (ORFs) occurring after repair of rhegmatogenous retinal detachment (RRD) using spectral domain-optical coherence tomography (sd-OCT) and fundus autofluorescence (FAF), and to discuss their pathogenesis. Twenty patients were operated on with 25-gauge pars plana vitrectomy and 20% sulfur hexafluoride gas injection for primary macula-off RRD repair and were followed prospectively. Sd-OCT and FAF images were recorded at 1, 3 and 6 months postoperatively. ORFs appeared on sd-OCT as hyperreflective lesions consisting of folded inner segment/outer segment of photoreceptors band and external limiting membrane band. Corresponding lines of increased or decreased autofluorescence were observed on FAF. Over the follow-up, the thick hypoautofluorescent lines progressively evolved to thick hyperautofluorescent lines and to thin hyperautofluorescent lines and eventually disappeared. Concomitantly, OCT scans revealed that the corresponding hyperreflective lesions decreased in number, height, and size. In six cases FAF assessment at month 6 was precluded by cataract development. ORFS tend to resolve spontaneously within a few months from operation leaving no or subtle abnormalities at the level of the outer retinal layers. OCT is superior to FAF to follow the evolution of orfs in phakic eyes. The following factors might be involved in ORFS pathogenesis: structural changes occurring in the detached retina, residual pockets of subretinal fluid after retinal reattachment, intravitreal gas, unintentional retinal translocation, and intraoperative or perioperative hypotony.

Graefe's Archive for Clinical and Experimental Ophthalmology, 2013

Background To compare anatomical, functional outcomes and complications of high-speed 25-gauge (G... more Background To compare anatomical, functional outcomes and complications of high-speed 25-gauge (G) pars plana vitrectomy (PPV) versus 20-G PPV for the management of primary inferior rhegmatogenous retinal detachment (RRD) associated to inferior breaks/holes. Methods Eighty-five eyes from 85 patients with a minimum follow-up of 3 months were retrospectively evaluated. Forty-one patients underwent 25-G and 44 patients underwent 20-G PPV. All patients underwent PPV with fluid-air exchange, sulfur hexafluoride (SF6) 20 % gas tamponade and laser or cryo retinopexy. Results The mean follow-up interval was 6.51(±2.32) and 6.63 (±2.58) months in the 25-G and 20-G groups respectively. Single-operation success rate was 92.7 % for the 25-G group and 81.8 % for the 20-G group (P 00.24). Postoperative hypotony was observed in no case. Redetachment occurred in 3 eyes operated on with 25-G and in 8 eyes operated on with 20-G system. All retinas were attached at final follow-up. Logarithm of the minimum angle of resolution visual acuity significantly improved from 0.69±0.76 to 0.33±0.37 in the 25-G and from 0.47±0.59 to 0.21±0.28 in the 20-G group (P00.0007 and P<0.0001 respectively). Conclusions High-speed PPV and SF6 gas tamponade using either 25-G or 20-G PPV system, yields similar single operation anatomical success rates for the repair of uncomplicated, primary inferior RRDs associated to inferior breaks.

British Journal of Ophthalmology, 2011

Aims: Previously we have identified neurofilament protein containing neurites in human epiretinal... more Aims: Previously we have identified neurofilament protein containing neurites in human epiretinal membranes (ERMs). The goal of this study was to further characterise these neurites by examining the expression of additional specific proteins in human ERMs and correlate this expression with various retinal disease conditions.

British Journal of Ophthalmology, 2012

British Journal of Ophthalmology, 2007

Background: By using dyes, it is easier to identify the extent of an epiretinal membrane (ERM) or... more Background: By using dyes, it is easier to identify the extent of an epiretinal membrane (ERM) or the inner limiting membrane (ILM) during surgery. Trypan blue (TB) stains ERM and ILM weakly, but with less apparent toxicity than other intraocular dyes. Its main drawback in vitreoretinal surgery is the requirement of an airfluid exchange (AFX) before its use. Aim: To propose a modified form of TB denser than water, thus obviating the need for an AFX. Design: A prospective, consecutive trial with heavy trypan blue in vitreoretinal surgery. Methods: A consecutive group of patients with ERMs was recruited prospectively. Patients were operated on using conventional methods. Heavy TB was prepared by mixing glucose 10% with Membrane blue (Dorc, Zuidland, The Netherlands) isovolumetrically. Patients were preoperatively and postoperatively assessed at 3 and 6 months (vision and ocular coherence tomography (OCT)). Ease of surgery was also assessed. Results: 29 eyes were included in the study. Reapplication of dye was necessary in 25% of the cases, leading to improved contrast further facilitating the peeling process. In no case was an AFX necessary to obtain sufficient staining. All patients with ERM had an improvement in vision (from median 0.30 to 0.55) and macular volume and foveal thickness (from median 450 to 238 mm) on OCT. No retinal detachment or other complications developed as a result of surgery. Conclusion: Heavy TB can be delivered efficiently to the retinal surface without an AFX. Staining was sufficient to allow a safe and efficient peeling of ERM. Repeat applications were easily performed. Its use was associated with vision improvement and decreased in foveal thickness, and the absence of adverse events in this small case series.

British Journal of Ophthalmology, 2007

Aim: To determine whether neural elements are present in subretinal and epiretinal proliferative ... more Aim: To determine whether neural elements are present in subretinal and epiretinal proliferative vitreoretinopathy (PVR) membranes as well as in diabetic, fibrovascular membranes removed from patients during vitrectomy surgery. Methods: Human subretinal and epiretinal membranes of varying durations were immunolabelled with different combinations of antibodies to glial fibrillary acidic protein, vimentin, neurofilament protein and laminin. Results: Anti-neurofilament-labelled neurites from presumptive ganglion cells were frequently found in epiretinal membranes and occasionally found in subretinal membranes. In addition, the neurites were only observed in regions that also contained glial processes. Conclusions: These data demonstrate that neuronal processes are commonly found in human peri-retinal cellular membranes similar to that demonstrated in animal models. These data also suggest that glial cells growing out of the neural retina form a permissive substrate for neurite growth and thus may hold clues to factors that support this growth.

British Journal of Ophthalmology, 2010

Purpose: To evaluate the incidence and characteristics of iatrogenic retinal breaks in 20-gauge m... more Purpose: To evaluate the incidence and characteristics of iatrogenic retinal breaks in 20-gauge macular surgery with an intensified search strategy. Design: Retrospective, non-comparative interventional case series. Participants: 218 consecutive operations in 209 patients who underwent 20-gauge vitrectomy vitrectomy for idiopathic macular pucker or idiopathic macular hole. Methods: Retrospective review of patient records undergoing 20-gauge vitrectomy with intensified peripheral search for retinal defects. Main outcome measures: Incidence of breaks related to the sclerotomies, the incidence of breaks occurring elsewhere, the incidence of lesions suspicious for traction, the location of identified breaks and intraoperative induction of posterior vitreous detachment.

British Journal of Ophthalmology, 2008

Ganglion cell neurites in human idiopathic http://bjo.bmj.com/cgi/content/full/92/7/981 Updated i... more Ganglion cell neurites in human idiopathic http://bjo.bmj.com/cgi/content/full/92/7/981 Updated information and services can be found at:

British Journal of Ophthalmology, 2013

To compare the outcome of air tamponade with gas tamponade in primary vitrectomy for the treatmen... more To compare the outcome of air tamponade with gas tamponade in primary vitrectomy for the treatment of rhegmatogenous retinal detachment (RRD). We examined the records of 524 cases of 523 patients that underwent primary vitrectomy for RRD with air or sulphur hexafluoride 20% gas tamponade and a follow-up of at least 3 months, excluding cases with inferior retinal breaks. 318 cases were treated with gas and 128 cases with air. Overall, vitrectomy led to an attached retina after a single operation in 85.1% of cases. Eyes treated with air had an 81.0% chance of primary success and those treated with gas had an 86.9% success rate (p=0.083, NS, χ(2) test). Involvement of lower retinal quadrants in the retinal detachment was revealed as a significant confounding factor. After correction for this confounder using a multivariate logistic regression model, air versus gas tamponade became a statistically significant determinant for success rate (OR 1.97; p=0.012). In a sub-analysis, eyes with a retinal detachment that involved the inferior quadrants had significantly lower primary success rates when using air tamponade (69.6%), compared to gas tamponade (84.7%; p=0.009, χ(2) test). Gas tamponade is superior to air tamponade in retinal detachment cases with involvement of the lower quadrants. These results suggest that air tamponade should only be used in retinal detachments that are restricted to the superior quadrants. Further prospective study is needed to confirm these findings, and to address functional outcome.

American Journal of Ophthalmology, 2010

PURPOSE: To describe the functional and anatomic results of retinectomy without scleral buckling ... more PURPOSE: To describe the functional and anatomic results of retinectomy without scleral buckling for anterior proliferative vitreoretinopathy in eyes that did not undergo previous buckling surgery. • DESIGN: Retrospective, nonrandomized, interventional case series. • METHODS: We reviewed the results of 123 consecutive cases of retinectomy for rhegmatogenous retinal detachment complicated by anterior proliferative vitreoretinopathy. The primary outcome measure was anatomic success, defined as complete retinal reattachment. Secondary outcome measures were final anatomic success, final visual acuity outcome, number of operations required for retinal reattachment, baseline extent of proliferative vitreoretinopathy, ocular pressure at final follow-up, extent of retinectomy, and occurrence of complications. • RESULTS: The anatomic success rate was 77.2%. Final attachment rate was 95.9%, reached after 1 rhegmatogenous retinal detachment reoperation in 21 cases and after 2 rhegmatogenous retinal detachment reoperations in 4 cases. We had a low rate of postoperative hypotony (4.1%). Visual acuity was significantly improved from 2.10 to 1.44 logarithm of the minimal angle of resolution units (P < .001). Improvement was related significantly to retinectomy extent and primary anatomic success. • CONCLUSIONS: Our results show that primary retinectomy without scleral buckling has good anatomic and functional results. (Am J Ophthalmol 2010; 149:447-452.

American Journal of Ophthalmology, 2011

To assess the risks of vitrectomy for the removal of primary and secondary vitreous opacities. Re... more To assess the risks of vitrectomy for the removal of primary and secondary vitreous opacities. Retrospective, nonrandomized, interventional case series. We reviewed the results of 116 consecutive cases of vitrectomy for vitreous floaters. Eighty-six cases were primary and 30 cases were secondary floaters. Main outcome measures were the incidence of iatrogenic retinal breaks and postoperative rhegmatogenous retinal detachments. We found iatrogenic retinal breaks in 16.4% of operations. There was no statistically significant difference in risk between cases of primary and secondary floaters. Intraoperative posterior vitreous detachment induction was found to increase significantly the risk of breaks. Retinal detachment occurred in 3 cases (2.5%), all after operations for primary floaters. One case of complicated retinal detachment ended with a low visual acuity of hand movements. Cataract occurred in 50% of phakic cases. Transient postoperative hypotony was found after 5.2% of our operations, and transient postoperative high intraocular pressure was encountered in 7.8%. An intraoperative choroidal hemorrhage occurred in 1 case, which resolved spontaneously. The mean visual acuity improved from 0.20 to 0.13 logarithm of the minimal angle of resolution units. The risk profile of vitrectomy for floaters is comparable with that of vitrectomy for other elective indications. Retinal breaks are a common finding during surgery and treatment of these breaks is crucial for the prevention of postoperative retinal detachment. Patients considering surgery for floaters should be informed specifically about the risks involved.

Acta Ophthalmologica, 2013

To establish whether differences in the assessment of diabetic macular oedema (DME) with either o... more To establish whether differences in the assessment of diabetic macular oedema (DME) with either optical coherence tomography (OCT) or stereoscopic biomicroscopy lead to variability in the photocoagulation treatment of DME. The differences in the assessment of DME with either OCT or stereoscopic biomicroscopy were analysed by calculating the surface areas and the overlap of retinal thickening. Photocoagulation treatment plans of retinal specialists were compared by evaluating the number and location of planned laser spots. The threshold for and dosage of photocoagulation differ depending upon whether the basis of retinal thickness diagnosis is clinical observation or OCT. The overlap in laser spot location based on the assessment of DME with OCT or biomicroscopy averages 51%. Among retinal specialists, the treatment plans differed in the laser spot count by six- to 11-fold. Diabetic macular oedema photocoagulation treatment threshold and dosage of laser spots differ depending on whether thickness assessments are based on stereoscopic slit-lamp biomicroscopy or OCT. In addition, retinal specialists differed in the number and placement of planned laser spots even when given identical information concerning DME and treatable lesions. This variability in the photocoagulation treatment of DME could lead to differences in patient outcome and laser study results.

American Journal of Ophthalmology

The British journal of ophthalmology

Journal of cell communication and signaling, 2013

In proliferative diabetic retinopathy (PDR), vascular endothelial growth factor (VEGF) and CCN2 (... more In proliferative diabetic retinopathy (PDR), vascular endothelial growth factor (VEGF) and CCN2 (connective tissue growth factor; CTGF) cause blindness by neovascularization and subsequent fibrosis. This angio-fibrotic switch is associated with a shift in the balance between vitreous levels of CCN2 and VEGF in the eye. Here, we investigated the possible involvement of other important mediators of fibrosis, tissue inhibitor of metalloproteinases (TIMP)-1 and transforming growth factor (TGF)-β2, and of the matrix metalloproteinases (MMP)-2 and MMP-9, in the natural course of PDR. TIMP-1, activated TGF-β2, CCN2 and VEGF levels were measured by ELISA in 78 vitreous samples of patients with PDR (n = 28), diabetic patients without PDR (n = 24), and patients with the diabetes-unrelated retinal conditions macular hole (n = 10) or macular pucker (n = 16), and were related to MMP-2 and MMP-9 activity on zymograms and to clinical data, including degree of intra-ocular neovascularization and fi...

Molecular vision, 2011

To quantify the extent of cellular proliferation and immunohistochemically characterize the proli... more To quantify the extent of cellular proliferation and immunohistochemically characterize the proliferating cell types in epiretinal membranes (ERMS) from four different conditions: proliferative vitreoretinopathy (PVR), proliferative diabetic retinopathy, post-retinal detachment, and idiopathic ERM. Forty-six ERMs were removed from patients undergoing vitrectomy and immediately fixed in paraformaldehyde. The membranes were processed whole and immunolabeled with either anti-MIB-1 or anti-SP6 to detect the K(i)-67 protein in proliferating cells, in combination with anti-glial fibrillary acidic protein or anti-vimentin to identify glia, anti-ezrin to identify retinal pigment epithelial cells, Ricinus communis to identify immune cells, and Hoechst to label nuclei. Digital images were collected using a laser scanning confocal microscope. The cell types were identified, their combined proliferative indices were tabulated as the average number of anti-K(i)-67-positive cells/mm(2) of tissue,...

Retina, 2012

To describe fundus autofluorescence and optical coherence tomography (OCT) features of the macula... more To describe fundus autofluorescence and optical coherence tomography (OCT) features of the macula after pars plana vitrectomy for rhegmatogenous retinal detachment. Thirty-three eyes of 33 consecutive patients with repaired rhegmatogenous retinal detachment with or without the involvement of the macula were prospectively investigated with simultaneous fundus autofluorescence and OCT imaging using the Spectralis HRA+OCT (Heidelberg Engineering, Heidelberg, Germany) within a few weeks after the operation. Fundus autofluorescence imaging of the macula showed lines of increased and decreased autofluorescence in 19 cases (57.6%). On OCT, these lines corresponded to the following abnormalities: outer retinal folds, inner retinal folds, and skip reflectivity abnormalities of the photoreceptor inner segment/outer segment band. Other OCT findings, not related to abnormal lines on fundus autofluorescence, consisted of disruption of photoreceptor inner segment/outer segment band and collection of intraretinal or subretinal fluid. The presence of outer retinal folds significantly related to metamorphopsia but did not relate to poor postoperative visual acuity. Partial-thickness retinal folds occur commonly after vitrectomy for rhegmatogenous retinal detachment repair and may represent an important anatomical substrate for postoperative metamorphopsia. Fundus autofluorescence and OCT are both sensitive techniques for the detection of these abnormalities.

Retina, 2012

To describe the incidence and outcome of retinal breaks in vitrectomy for retained lens fragments... more To describe the incidence and outcome of retinal breaks in vitrectomy for retained lens fragments. This is a retrospective noncomparative interventional case series. Medical records of consecutive cases of vitrectomy for retained lens fragments over a period of 4 years were reviewed. Main outcome measures were incidence of breaks, visual acuity outcome, and occurrence of postoperative complications. We included 89 consecutive cases in 89 patients. The median interval between cataract surgery and vitrectomy was 2 days (range, 0-106 days). Visual acuity at last follow-up was ≥ 0.5 in 70% of cases. During surgery, retinal breaks were found in 29% of cases. Induction of a posterior vitreous detachment, the use of a fragmatome, or delay between cataract surgery and vitrectomy did not influence retinal break incidence. Postoperative retinal detachment occurred in only 2% of cases. Other complications were intraoperative choroidal hemorrhage in 1 case, postoperative macular pucker in 2, postoperative macular edema in 1, and glaucoma in 2 cases. We identified a high number of retinal breaks during vitrectomy for retained lens fragments. Prophylactic treatment of breaks and other areas of retinal traction seem to reduce the risk of postoperative retinal detachment.

Investigative Ophthalmology & Visual Science, 2012

To assess the evolution of outer retinal folds (ORFs) occurring after repair of rhegmatogenous re... more To assess the evolution of outer retinal folds (ORFs) occurring after repair of rhegmatogenous retinal detachment (RRD) using spectral domain-optical coherence tomography (sd-OCT) and fundus autofluorescence (FAF), and to discuss their pathogenesis. Twenty patients were operated on with 25-gauge pars plana vitrectomy and 20% sulfur hexafluoride gas injection for primary macula-off RRD repair and were followed prospectively. Sd-OCT and FAF images were recorded at 1, 3 and 6 months postoperatively. ORFs appeared on sd-OCT as hyperreflective lesions consisting of folded inner segment/outer segment of photoreceptors band and external limiting membrane band. Corresponding lines of increased or decreased autofluorescence were observed on FAF. Over the follow-up, the thick hypoautofluorescent lines progressively evolved to thick hyperautofluorescent lines and to thin hyperautofluorescent lines and eventually disappeared. Concomitantly, OCT scans revealed that the corresponding hyperreflective lesions decreased in number, height, and size. In six cases FAF assessment at month 6 was precluded by cataract development. ORFS tend to resolve spontaneously within a few months from operation leaving no or subtle abnormalities at the level of the outer retinal layers. OCT is superior to FAF to follow the evolution of orfs in phakic eyes. The following factors might be involved in ORFS pathogenesis: structural changes occurring in the detached retina, residual pockets of subretinal fluid after retinal reattachment, intravitreal gas, unintentional retinal translocation, and intraoperative or perioperative hypotony.

Graefe's Archive for Clinical and Experimental Ophthalmology, 2013

Background To compare anatomical, functional outcomes and complications of high-speed 25-gauge (G... more Background To compare anatomical, functional outcomes and complications of high-speed 25-gauge (G) pars plana vitrectomy (PPV) versus 20-G PPV for the management of primary inferior rhegmatogenous retinal detachment (RRD) associated to inferior breaks/holes. Methods Eighty-five eyes from 85 patients with a minimum follow-up of 3 months were retrospectively evaluated. Forty-one patients underwent 25-G and 44 patients underwent 20-G PPV. All patients underwent PPV with fluid-air exchange, sulfur hexafluoride (SF6) 20 % gas tamponade and laser or cryo retinopexy. Results The mean follow-up interval was 6.51(±2.32) and 6.63 (±2.58) months in the 25-G and 20-G groups respectively. Single-operation success rate was 92.7 % for the 25-G group and 81.8 % for the 20-G group (P 00.24). Postoperative hypotony was observed in no case. Redetachment occurred in 3 eyes operated on with 25-G and in 8 eyes operated on with 20-G system. All retinas were attached at final follow-up. Logarithm of the minimum angle of resolution visual acuity significantly improved from 0.69±0.76 to 0.33±0.37 in the 25-G and from 0.47±0.59 to 0.21±0.28 in the 20-G group (P00.0007 and P<0.0001 respectively). Conclusions High-speed PPV and SF6 gas tamponade using either 25-G or 20-G PPV system, yields similar single operation anatomical success rates for the repair of uncomplicated, primary inferior RRDs associated to inferior breaks.

British Journal of Ophthalmology, 2011

Aims: Previously we have identified neurofilament protein containing neurites in human epiretinal... more Aims: Previously we have identified neurofilament protein containing neurites in human epiretinal membranes (ERMs). The goal of this study was to further characterise these neurites by examining the expression of additional specific proteins in human ERMs and correlate this expression with various retinal disease conditions.

British Journal of Ophthalmology, 2012

British Journal of Ophthalmology, 2007

Background: By using dyes, it is easier to identify the extent of an epiretinal membrane (ERM) or... more Background: By using dyes, it is easier to identify the extent of an epiretinal membrane (ERM) or the inner limiting membrane (ILM) during surgery. Trypan blue (TB) stains ERM and ILM weakly, but with less apparent toxicity than other intraocular dyes. Its main drawback in vitreoretinal surgery is the requirement of an airfluid exchange (AFX) before its use. Aim: To propose a modified form of TB denser than water, thus obviating the need for an AFX. Design: A prospective, consecutive trial with heavy trypan blue in vitreoretinal surgery. Methods: A consecutive group of patients with ERMs was recruited prospectively. Patients were operated on using conventional methods. Heavy TB was prepared by mixing glucose 10% with Membrane blue (Dorc, Zuidland, The Netherlands) isovolumetrically. Patients were preoperatively and postoperatively assessed at 3 and 6 months (vision and ocular coherence tomography (OCT)). Ease of surgery was also assessed. Results: 29 eyes were included in the study. Reapplication of dye was necessary in 25% of the cases, leading to improved contrast further facilitating the peeling process. In no case was an AFX necessary to obtain sufficient staining. All patients with ERM had an improvement in vision (from median 0.30 to 0.55) and macular volume and foveal thickness (from median 450 to 238 mm) on OCT. No retinal detachment or other complications developed as a result of surgery. Conclusion: Heavy TB can be delivered efficiently to the retinal surface without an AFX. Staining was sufficient to allow a safe and efficient peeling of ERM. Repeat applications were easily performed. Its use was associated with vision improvement and decreased in foveal thickness, and the absence of adverse events in this small case series.

British Journal of Ophthalmology, 2007

Aim: To determine whether neural elements are present in subretinal and epiretinal proliferative ... more Aim: To determine whether neural elements are present in subretinal and epiretinal proliferative vitreoretinopathy (PVR) membranes as well as in diabetic, fibrovascular membranes removed from patients during vitrectomy surgery. Methods: Human subretinal and epiretinal membranes of varying durations were immunolabelled with different combinations of antibodies to glial fibrillary acidic protein, vimentin, neurofilament protein and laminin. Results: Anti-neurofilament-labelled neurites from presumptive ganglion cells were frequently found in epiretinal membranes and occasionally found in subretinal membranes. In addition, the neurites were only observed in regions that also contained glial processes. Conclusions: These data demonstrate that neuronal processes are commonly found in human peri-retinal cellular membranes similar to that demonstrated in animal models. These data also suggest that glial cells growing out of the neural retina form a permissive substrate for neurite growth and thus may hold clues to factors that support this growth.

British Journal of Ophthalmology, 2010

Purpose: To evaluate the incidence and characteristics of iatrogenic retinal breaks in 20-gauge m... more Purpose: To evaluate the incidence and characteristics of iatrogenic retinal breaks in 20-gauge macular surgery with an intensified search strategy. Design: Retrospective, non-comparative interventional case series. Participants: 218 consecutive operations in 209 patients who underwent 20-gauge vitrectomy vitrectomy for idiopathic macular pucker or idiopathic macular hole. Methods: Retrospective review of patient records undergoing 20-gauge vitrectomy with intensified peripheral search for retinal defects. Main outcome measures: Incidence of breaks related to the sclerotomies, the incidence of breaks occurring elsewhere, the incidence of lesions suspicious for traction, the location of identified breaks and intraoperative induction of posterior vitreous detachment.

British Journal of Ophthalmology, 2008

Ganglion cell neurites in human idiopathic http://bjo.bmj.com/cgi/content/full/92/7/981 Updated i... more Ganglion cell neurites in human idiopathic http://bjo.bmj.com/cgi/content/full/92/7/981 Updated information and services can be found at:

British Journal of Ophthalmology, 2013

To compare the outcome of air tamponade with gas tamponade in primary vitrectomy for the treatmen... more To compare the outcome of air tamponade with gas tamponade in primary vitrectomy for the treatment of rhegmatogenous retinal detachment (RRD). We examined the records of 524 cases of 523 patients that underwent primary vitrectomy for RRD with air or sulphur hexafluoride 20% gas tamponade and a follow-up of at least 3 months, excluding cases with inferior retinal breaks. 318 cases were treated with gas and 128 cases with air. Overall, vitrectomy led to an attached retina after a single operation in 85.1% of cases. Eyes treated with air had an 81.0% chance of primary success and those treated with gas had an 86.9% success rate (p=0.083, NS, χ(2) test). Involvement of lower retinal quadrants in the retinal detachment was revealed as a significant confounding factor. After correction for this confounder using a multivariate logistic regression model, air versus gas tamponade became a statistically significant determinant for success rate (OR 1.97; p=0.012). In a sub-analysis, eyes with a retinal detachment that involved the inferior quadrants had significantly lower primary success rates when using air tamponade (69.6%), compared to gas tamponade (84.7%; p=0.009, χ(2) test). Gas tamponade is superior to air tamponade in retinal detachment cases with involvement of the lower quadrants. These results suggest that air tamponade should only be used in retinal detachments that are restricted to the superior quadrants. Further prospective study is needed to confirm these findings, and to address functional outcome.

American Journal of Ophthalmology, 2010

PURPOSE: To describe the functional and anatomic results of retinectomy without scleral buckling ... more PURPOSE: To describe the functional and anatomic results of retinectomy without scleral buckling for anterior proliferative vitreoretinopathy in eyes that did not undergo previous buckling surgery. • DESIGN: Retrospective, nonrandomized, interventional case series. • METHODS: We reviewed the results of 123 consecutive cases of retinectomy for rhegmatogenous retinal detachment complicated by anterior proliferative vitreoretinopathy. The primary outcome measure was anatomic success, defined as complete retinal reattachment. Secondary outcome measures were final anatomic success, final visual acuity outcome, number of operations required for retinal reattachment, baseline extent of proliferative vitreoretinopathy, ocular pressure at final follow-up, extent of retinectomy, and occurrence of complications. • RESULTS: The anatomic success rate was 77.2%. Final attachment rate was 95.9%, reached after 1 rhegmatogenous retinal detachment reoperation in 21 cases and after 2 rhegmatogenous retinal detachment reoperations in 4 cases. We had a low rate of postoperative hypotony (4.1%). Visual acuity was significantly improved from 2.10 to 1.44 logarithm of the minimal angle of resolution units (P < .001). Improvement was related significantly to retinectomy extent and primary anatomic success. • CONCLUSIONS: Our results show that primary retinectomy without scleral buckling has good anatomic and functional results. (Am J Ophthalmol 2010; 149:447-452.

American Journal of Ophthalmology, 2011

To assess the risks of vitrectomy for the removal of primary and secondary vitreous opacities. Re... more To assess the risks of vitrectomy for the removal of primary and secondary vitreous opacities. Retrospective, nonrandomized, interventional case series. We reviewed the results of 116 consecutive cases of vitrectomy for vitreous floaters. Eighty-six cases were primary and 30 cases were secondary floaters. Main outcome measures were the incidence of iatrogenic retinal breaks and postoperative rhegmatogenous retinal detachments. We found iatrogenic retinal breaks in 16.4% of operations. There was no statistically significant difference in risk between cases of primary and secondary floaters. Intraoperative posterior vitreous detachment induction was found to increase significantly the risk of breaks. Retinal detachment occurred in 3 cases (2.5%), all after operations for primary floaters. One case of complicated retinal detachment ended with a low visual acuity of hand movements. Cataract occurred in 50% of phakic cases. Transient postoperative hypotony was found after 5.2% of our operations, and transient postoperative high intraocular pressure was encountered in 7.8%. An intraoperative choroidal hemorrhage occurred in 1 case, which resolved spontaneously. The mean visual acuity improved from 0.20 to 0.13 logarithm of the minimal angle of resolution units. The risk profile of vitrectomy for floaters is comparable with that of vitrectomy for other elective indications. Retinal breaks are a common finding during surgery and treatment of these breaks is crucial for the prevention of postoperative retinal detachment. Patients considering surgery for floaters should be informed specifically about the risks involved.

Acta Ophthalmologica, 2013

To establish whether differences in the assessment of diabetic macular oedema (DME) with either o... more To establish whether differences in the assessment of diabetic macular oedema (DME) with either optical coherence tomography (OCT) or stereoscopic biomicroscopy lead to variability in the photocoagulation treatment of DME. The differences in the assessment of DME with either OCT or stereoscopic biomicroscopy were analysed by calculating the surface areas and the overlap of retinal thickening. Photocoagulation treatment plans of retinal specialists were compared by evaluating the number and location of planned laser spots. The threshold for and dosage of photocoagulation differ depending upon whether the basis of retinal thickness diagnosis is clinical observation or OCT. The overlap in laser spot location based on the assessment of DME with OCT or biomicroscopy averages 51%. Among retinal specialists, the treatment plans differed in the laser spot count by six- to 11-fold. Diabetic macular oedema photocoagulation treatment threshold and dosage of laser spots differ depending on whether thickness assessments are based on stereoscopic slit-lamp biomicroscopy or OCT. In addition, retinal specialists differed in the number and placement of planned laser spots even when given identical information concerning DME and treatable lesions. This variability in the photocoagulation treatment of DME could lead to differences in patient outcome and laser study results.