The Experts below are selected from a list of 1362 Experts worldwide ranked by ideXlab platform
Matthew M Harper - One of the best experts on this subject based on the ideXlab platform.
-
extracellular superoxide dismutase sod3 regulates oxidative stress at the vitreoretinal interface
Free Radical Biology and Medicine, 2018Co-Authors: Katherine J Wert, Gabriel Velez, Madeline R Cross, Brett A Wagner, Melissa Teohfitzgerald, Garry R Buettner, Jason J Mcanany, Alicia K Olivier, S Tsang, Matthew M HarperAbstract:Oxidative stress is a pathogenic feature in vitreoretinal disease. However, the ability of the inner retina to manage metabolic waste and oxidative stress is unknown. Proteomic analysis of antioxidants in the human Vitreous, the extracellular matrix opposing the inner retina, identified superoxide dismutase-3 (SOD3) that localized to a unique matrix structure in the Vitreous Base and cortex. To determine the role of SOD3, Sod3-/- mice underwent histological and clinical phenotyping. Although the eyes were structurally normal, at the vitreoretinal interface Sod3-/- mice demonstrated higher levels of 3-nitrotyrosine, a key marker of oxidative stress. Pattern electroretinography also showed physiological signaling abnormalities within the inner retina. Vitreous biopsies and epiretinal membranes collected from patients with diabetic vitreoretinopathy (DVR) and a mouse model of DVR showed significantly higher levels of nitrates and/or 3-nitrotyrosine oxidative stress biomarkers suggestive of SOD3 dysfunction. This study analyzes the molecular pathways that regulate oxidative stress in human Vitreous substructures. The absence or dysregulation of the SOD3 antioxidant at the Vitreous Base and cortex results in increased oxidative stress and tissue damage to the inner retina, which may underlie DVR pathogenesis and other vitreoretinal diseases.
Katherine J Wert - One of the best experts on this subject based on the ideXlab platform.
-
extracellular superoxide dismutase sod3 regulates oxidative stress at the vitreoretinal interface
Free Radical Biology and Medicine, 2018Co-Authors: Katherine J Wert, Gabriel Velez, Madeline R Cross, Brett A Wagner, Melissa Teohfitzgerald, Garry R Buettner, Jason J Mcanany, Alicia K Olivier, S Tsang, Matthew M HarperAbstract:Oxidative stress is a pathogenic feature in vitreoretinal disease. However, the ability of the inner retina to manage metabolic waste and oxidative stress is unknown. Proteomic analysis of antioxidants in the human Vitreous, the extracellular matrix opposing the inner retina, identified superoxide dismutase-3 (SOD3) that localized to a unique matrix structure in the Vitreous Base and cortex. To determine the role of SOD3, Sod3-/- mice underwent histological and clinical phenotyping. Although the eyes were structurally normal, at the vitreoretinal interface Sod3-/- mice demonstrated higher levels of 3-nitrotyrosine, a key marker of oxidative stress. Pattern electroretinography also showed physiological signaling abnormalities within the inner retina. Vitreous biopsies and epiretinal membranes collected from patients with diabetic vitreoretinopathy (DVR) and a mouse model of DVR showed significantly higher levels of nitrates and/or 3-nitrotyrosine oxidative stress biomarkers suggestive of SOD3 dysfunction. This study analyzes the molecular pathways that regulate oxidative stress in human Vitreous substructures. The absence or dysregulation of the SOD3 antioxidant at the Vitreous Base and cortex results in increased oxidative stress and tissue damage to the inner retina, which may underlie DVR pathogenesis and other vitreoretinal diseases.
Gian Maria Cavallini - One of the best experts on this subject based on the ideXlab platform.
-
Limited Vitrectomy versus Complete Vitrectomy for Epiretinal Membranes: A Comparative Multicenter Trial.
Journal of ophthalmology, 2020Co-Authors: Matteo Forlini, Purva Date, Domenico D’eliseo, Paolo Maria Rossini, Adriana Bratu, Andrea Volinia, G. Neri, Tommaso Verdina, Maria Rosaria Carbotti, Gian Maria CavalliniAbstract:Purpose. To evaluate whether limited vitrectomy is as effective as complete vitrectomy in eyes with epiretinal membrane (ERM) and to compare the surgical times and rates of complications. Methods. In this multicentre European study, data of eyes with ERM that underwent vitrectomy from January 2017 to July 2018 were analyzed retrospectively. In the limited vitrectomy group, a posterior Vitreous detachment (PVD) was induced up till the equator as opposed to complete PVD induction till the Vitreous Base in the comparison group. Incidence of iatrogenic retinal breaks, retinal detachment, surgical time, and visual outcomes were compared between groups. Results. We included 139 eyes in the analysis with a mean age being 72.2 ± 6.9 years. In this, sixty-five eyes (47%) underwent limited vitrectomy and 74 eyes (53%) underwent complete vitrectomy. Iatrogenic retinal tears were seen in both groups (5% in limited vitrectomy versus 7% in complete vitrectomy, ). Retinal detachment occurred in 2 eyes in the limited vitrectomy group (3%) compared to none in the complete vitrectomy group ( ). Best-corrected visual acuity (BCVA) and central macular thickness improved significantly with no intergroup differences ( ). Surgical time was significantly shorter in the limited vitrectomy group with 91% surgeries taking less than 1 hour compared to 71% in the complete vitrectomy group ( ). Conclusion. A limited vitrectomy is a time-efficient and effective surgical procedure for removal of epiretinal membrane with no additional complications.
-
Limited Vitrectomy versus Complete Vitrectomy for Epiretinal Membranes: A Comparative Multicenter Trial
'Hindawi Limited', 2020Co-Authors: Matteo Forlini, Purva Date, Domenico D’eliseo, Adriana Bratu, Andrea Volinia, G. Neri, Tommaso Verdina, Maria Rosaria Carbotti, Paolo Rossini, Gian Maria CavalliniAbstract:Purpose. To evaluate whether limited vitrectomy is as effective as complete vitrectomy in eyes with epiretinal membrane (ERM) and to compare the surgical times and rates of complications. Methods. In this multicentre European study, data of eyes with ERM that underwent vitrectomy from January 2017 to July 2018 were analyzed retrospectively. In the limited vitrectomy group, a posterior Vitreous detachment (PVD) was induced up till the equator as opposed to complete PVD induction till the Vitreous Base in the comparison group. Incidence of iatrogenic retinal breaks, retinal detachment, surgical time, and visual outcomes were compared between groups. Results. We included 139 eyes in the analysis with a mean age being 72.2 ± 6.9 years. In this, sixty-five eyes (47%) underwent limited vitrectomy and 74 eyes (53%) underwent complete vitrectomy. Iatrogenic retinal tears were seen in both groups (5% in limited vitrectomy versus 7% in complete vitrectomy, p=0.49). Retinal detachment occurred in 2 eyes in the limited vitrectomy group (3%) compared to none in the complete vitrectomy group (p=0.22). Best-corrected visual acuity (BCVA) and central macular thickness improved significantly with no intergroup differences (p=0.18). Surgical time was significantly shorter in the limited vitrectomy group with 91% surgeries taking less than 1 hour compared to 71% in the complete vitrectomy group (p
Homayoun Tabandeh - One of the best experts on this subject based on the ideXlab platform.
-
outcomes of small gauge vitreoretinal surgery without scleral depressed shaving of the Vitreous Base in the era of wide angle viewing systems
British Journal of Ophthalmology, 2019Co-Authors: Homayoun Tabandeh, Nikolas J S London, David S Boyer, Harry W. FlynnAbstract:Purpose To evaluate outcomes of small-gauge pars plana vitrectomy (PPV) for the treatment of rhegmatogenous retinal detachment (RD) without scleral-depressed shaving of the Vitreous Base. Methods Retrospective, consecutive case series. Surgical technique included small-gauge PPV (25G, 23G, 25G+ or 27G) and wide-angle vitrectomy viewing system in all cases. No cases were excluded Based on the level of complexity of RD. Outcome measures were retinal reattachment rates and Snellen visual acuity (best-corrected visual activity [BCVA]). Results 312 eyes of 301 patients, mean age 60.8 years, and mean follow-up 23.1 months. Baseline characteristics included macula-off RD in 207 (66%) eyes, psudophakia in 124 (40%) eyes, high myopia in 74 (24%) eyes and giant retinal tear in 14 (5%) eyes. The retina was reattached with one procedure in 296 (95%) eyes. Final retinal reattachment was achieved in 310 (99%) eyes. The BCVA at Baseline was >20/40 in 76 (24%) eyes, 20/50–20/100 in 48 (15%) eyes, 20/200–20/400 in 46 (15%) eyes and 20/40 in 168 (54%) eyes, 20/50–20/100 in 60 (19%) eyes, 20/200–20/400 in 49 (16%) eyes and Conclusion Small-gauge PPV without scleral-depressed Vitreous Base shaving can be associated with good anatomical and visual outcomes. Case selection Based on the complexity of RD may not be required when considering small-gauge PPV.
-
intraoperative visualization of peripheral retina with wide angle viewing systems
Investigative Ophthalmology & Visual Science, 2012Co-Authors: Homayoun Tabandeh, Francesco BosciaAbstract:BACKGROUND: Wide-angle viewing systems have significantly improved intraoperative visualization of peripheral retina. The static field of view for most systems is in the range 120 to 140 degrees. Intraoperative manipulations such as ocular rotation, lens tilting, and lens decenteration can further enhance peripheral viewing. From a surgical perspective it is more relevant to know the distance of an area of interest from the Ora Serrata, than from the optic disc. The current study evaluated the distance of the retina area that corresponded to A) the internal tip of the sclerotomy cannula and B) edge of the viewing field from the ora serrata. METHODS: Non-comparative, clinical case series. Participants: patients undergoing pars plana vitrectomy (PPV) and endolaser photocoagulation. Exclusion criteria included patients with pupil diameter <5mm. During PPV, the retina areas corresponding to the internal tip of the sclerotomy cannula and the edge of the viewing field were marked with endolaser photocoagulation. The ora serrata was visualized with scleral depression and the distance between the ora serrata and the laser marks were measured in “cannula diameter” units. The measurements were subsequently converted to millimeter units. RESULTS: 35 eyes of 35 patients were included in the study. Contact lens viewing system (OVI 130) was used in 23 eyes (group1) and a non-contact viewing system (BIOM) was used in 12 eyes (group2). The cannula tip was visualized in 22 (95%) eyes in group1, and in 10 (83%) eyes in group 2. The mean distance from the edge of the viewing field to ora serrata was 1.1 mm (range 0-2.9 mm) for group 1 and 1.2 mm (range 0.4-3.3 mm) for group 2. The mean distance from the cannula tip to ora serrata was 1.4 mm (range 0.3 to 2.9 mm) for the 32 subjects in which the tip of cannula could be visualized. The 3 eyes in which the cannula tip could not be visualized also had a longer field edge-ora distance. CONCLUSION: Internal tip of a sclerotomy cannula can serve as a useful landmark indicating proximity to the ora serrata. With the current wide-angle systems it is possible to visualize the peripheral retina to the vicinity of the Vitreous Base without the need for scleral depression in most cases. • Traditionally scleral depression is performed in order to visualize the Vitreous Base • Wide-angle viewing systems have significantly improved intraoperative visualization of peripheral retina • The static field of view for most systems is in the range 120 to 140 degrees • Intraoperative manipulations such as ocular rotation, lens tilting, and lens decenteration further enhance peripheral viewing • From a surgical perspective it is more relevant to know the distance of an area of interest from the Ora Serrata, than from the optic disc • Findings of the current study indicate that it is possible to visualize the peripheral retina to within 1 -2 mm of the ora serrata (within the vicinity of the Vitreous Base without the need for scleral depression • There does not seem to be a major difference in the extent of visualization of the peripheral retina between the contact vs. noncontact viewing systems • Non-comparative, clinical case series • Participants: patients undergoing PPV and endolaser photocoagulation • Exclusion criteria : patients with pupil diameter <5mm • During PPV, the retina areas corresponding to the internal tip of the sclerotomy cannula and the edge of the viewing field were marked with endolaser photocoagulation. The ora serrata was visualized with scleral depression and the distance between the ora serrata and the laser marks were measured in “cannula diameter” units. The measurements were subsequently converted to millimeter units. • Outcome measures: Distance of cannula tip from the ora serrata Distance of edge of the viewing field from the ora serrata CONCLUSION • 35 eyes of 35 patients. Contact lens viewing system (OVI 130) was used in 23 eyes (group1) and a non-contact viewing system (BIOM) was used in 12 eyes (group2). • Pupil diameter: Mean 7.2 mm, Range 5 – 9 mm • Lens status: Phakic 19, PCIOL 13, ACIOL 3 • Cannula tip was visualized in 22 (95%) eyes in group1, and in 10 (83%) eyes in group 2. The mean distance from the edge of the viewing field to ora serrata was 1.1 mm (range 0-2.9 mm) for group 1 and 1.2 mm (range 0.4-3.3 mm) for group 2. The mean distance from the cannula tip to ora serrata was 1.4 mm (range 0.3 to 2.9 mm) for the 32 subjects in which the tip of cannula could be visualized. The 3 eyes in which the cannula tip could not be visualized also had a longer field edge-ora distance. Cannula Tip Visualized Cannula Tip Distance from Ora Edge of Field Distance from Ora OVI 130 95% 1.3 mm (0.3 – 3.2) 1.1 mm (0 – 2.9) BIOM 83% 1.5 mm (0.5 – 3.6) 1.2 mm (0.4 – 3.3) “During pars plana vitrectomy the internal tip of a sclerotomy cannula can serve as a useful landmark indicating proximity to the ora serrata. With the current wide-angle systems it is possible to visualize the peripheral retina to the vicinity of the Vitreous Base without the need for scleral depression in most cases” DISCUSSION
Garry R Buettner - One of the best experts on this subject based on the ideXlab platform.
-
extracellular superoxide dismutase sod3 regulates oxidative stress at the vitreoretinal interface
Free Radical Biology and Medicine, 2018Co-Authors: Katherine J Wert, Gabriel Velez, Madeline R Cross, Brett A Wagner, Melissa Teohfitzgerald, Garry R Buettner, Jason J Mcanany, Alicia K Olivier, S Tsang, Matthew M HarperAbstract:Oxidative stress is a pathogenic feature in vitreoretinal disease. However, the ability of the inner retina to manage metabolic waste and oxidative stress is unknown. Proteomic analysis of antioxidants in the human Vitreous, the extracellular matrix opposing the inner retina, identified superoxide dismutase-3 (SOD3) that localized to a unique matrix structure in the Vitreous Base and cortex. To determine the role of SOD3, Sod3-/- mice underwent histological and clinical phenotyping. Although the eyes were structurally normal, at the vitreoretinal interface Sod3-/- mice demonstrated higher levels of 3-nitrotyrosine, a key marker of oxidative stress. Pattern electroretinography also showed physiological signaling abnormalities within the inner retina. Vitreous biopsies and epiretinal membranes collected from patients with diabetic vitreoretinopathy (DVR) and a mouse model of DVR showed significantly higher levels of nitrates and/or 3-nitrotyrosine oxidative stress biomarkers suggestive of SOD3 dysfunction. This study analyzes the molecular pathways that regulate oxidative stress in human Vitreous substructures. The absence or dysregulation of the SOD3 antioxidant at the Vitreous Base and cortex results in increased oxidative stress and tissue damage to the inner retina, which may underlie DVR pathogenesis and other vitreoretinal diseases.
