Changes in Anterior Segment Parameters Following Pars Plana Vitrectomy Measured by Ultrasound Biomicroscopy (UBM)

Despite being a posterior segment ocular surgery, pars plana vitrectomy (PPV) may also affect anterior segment parameters. We aimed to investigate anterior segment alterations following PPV using ultrasound biomicroscopy (UBM) to visualize the structural anatomy of the eye. In this study, we enrolled phakic patients undergoing PPV (as the sole procedure). The anterior chamber depth, crystalline lens anterior-posterior (AP) diameter, anterior chamber angle, ciliary body dimensions, and integrity of the ciliary zonules and posterior capsule were assessed using UBM before and at least 3 months after PPV. Seven eyes from seven patients were included in the study. The indications for PPV were rhegmatogenous retinal detachment (57%), epiretinal membrane (29%), and macular hole (14%). The mean age of the patients was 57.86 ± 6.56 years, and they were followed up for a mean of 131.57 ± 29.99 days. The crystalline lens AP diameter was the only parameter that changed significantly following PPV (p = 0.042). Thus, increases in the crystalline lens AP diameter, without significant changes in the anterior chamber depth, can be expected after PPV due to the development of nuclear sclerotic cataracts

Changes in Anterior Segment Parameters Following Pars Plana Vitrectomy Measured by Ultrasound Biomicroscopy (UBM)

Despite being a posterior segment ocular surgery, pars plana vitrectomy (PPV) may also affect anterior segment parameters. We aimed to investigate anterior segment alterations following PPV using ultrasound biomicroscopy (UBM) to visualize the structural anatomy of the eye. In this study, we enrolled phakic patients undergoing PPV (as the sole procedure). The anterior chamber depth, crystalline lens anterior-posterior (AP) diameter, anterior chamber angle, ciliary body dimensions, and integrity of the ciliary zonules and posterior capsule were assessed using UBM before and at least 3 months after PPV. Seven eyes from seven patients were included in the study. The indications for PPV were rhegmatogenous retinal detachment (57%), epiretinal membrane (29%), and macular hole (14%). The mean age of the patients was 57.86 ± 6.56 years, and they were followed up for a mean of 131.57 ± 29.99 days. The crystalline lens AP diameter was the only parameter that changed significantly following PPV (p = 0.042). Thus, increases in the crystalline lens AP diameter, without significant changes in the anterior chamber depth, can be expected after PPV due to the development of nuclear sclerotic cataracts

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Uveitis-induced Refractory Ocular Hypotony Managed with High-dose Latanoprost

Purpose: To report a case of refractory ocular hypotony due to chronic Behcet’s disease with good response to high-dose topical latanoprost. Case Report: We present a 26-year-old man with a known history of Behcet’s disease who developed decreasing vision and severe ocular hypotony that was refractory to multiple treatment modalities including subtenon triamcinolone acetonide, ibopamine, pars plana vitrectomy, and silicone oil injection. We decided to try high-dose topical latanoprost for the management of ocular hypotony based on recent reports. After six months, intraocular pressure (IOP) increased by 5 mm Hg, became stable at 7 mm Hg, and remained unchanged at month 24. Conclusion: High-dose topical latanoprost could lead to significant increase in IOP in uveitis-induced refractory ocular hypotony

Comparison of Three Different Techniques of Inverted Internal Limiting Membrane Flap in Treatment of Large Idiopathic Full-Thickness Macular Hole.

Purpose: To evaluate and compare three different techniques of inverted internal limiting membrane (ILM) flap in the treatment of large idiopathic full-thickness macular hole. Methods: In a comparative interventional case series, 72 eyes from 72 patients with large (\u3e 400 µm) full-thickness macular hole were randomly enrolled into three different groups: group A - hemicircular ILM peel with temporally hinged inverted flap; group B - circular ILM peel with temporally hinged inverted flap; and group C - circular ILM peel with superior inverted flap. Best-corrected visual acuity (BCVA), anatomical closure rate, and ellipsoid zone (EZ) or external limiting membrane (ELM) defects were evaluated preoperatively, at week 1, and months 1, 3 and 6 after surgery. Results: There were 24 eyes in group A, 23 in group B, and 25 in group C. In all three groups, larger diameter macular hole was associated with worse preoperative visual acuity (r=0.625, P\u3c0.001). Mean BCVA improved significantly in all three groups 6 months after surgery (0.91vs 0.55, p\u3c0.001). 6 months after surgery, mean BCVA improved from 0.91 logMAR to 0.52±0.06 in group A, 0.90 to 0.53±0.06 in group B, and 0.91 to 0.55±0.11 in group C. In group A vs. B vs. C, improvement of BCVA was 0.380±0.04 vs. 0.383±0.04 vs. 0.368±0.11 logMAR, with no statistically significant difference between groups (P=0.660). The rate of successful hole closure was 87.5% vs. 91.3% vs. 100%. Although the closure rate was 100% in Group C (circular ILM peel with superiorly hinged inverted flap), this difference was not statistically significant (P=0.115). Conclusion: ILM peel with an inverted flap is a highly effective procedure for the treatment of large, full-thickness macular hole. Different flap techniques have comparable results, indicating that the technique can be chosen based on surgeon preference

Evaluation of SD-208, a TGF-β-RI kinase inhibitor, as an anticancer agent in retinoblastoma

Retinoblastoma is the most common intraocular tumor in children resulting from genetic alterations and transformation of mature retinal cells. The objective of this study was to investigate the effects of SD-208, TGF-β-RI kinase inhibitor, on the expression of some miRNAs including a miR-17/92 cluster in retinoblastoma cells. Prior to initiate this work, the cell proliferation was studied by Methyl Thiazolyl Tetrazolium (MTT) and bromo-2′-deoxyuridine (BrdU) assays. Then, the expression patterns of four miRNAs (18a, 20a, 22, and 34a) were investigated in the treated SD-208 (0.0, 1, 2 and 3 μM) and untreated Y-79 cells. A remarkable inhibition of the cell proliferation was found in Y-79 cells treated with SD-208 versus untreated cells. Also, the expression changes were observed in miRNAs 18a, 20a, 22 and 34a in response to SD-208 treatment (P<0.05). The findings of the present study suggest that the anti-cancer effect of SD-208 may be exerted due to the regulation of specific miRNAs, at least in this particular retinoblastoma cell line. To the best of the researchers’ knowledge, this is the first report demonstrating that the SD-208 could alter the expression of tumor suppressive miRNAs as well as oncomiRs in vitro. In conclusion, the present data suggest that SD-208 could be an alternative agent in retinoblastoma treatment. © 2016 Tehran University of Medical Sciences. All rights reserved

Digoxin Inhibits Retinoblastoma through Suppressing a Non-canonical TGFβ Signaling Pathway.

Aims: Retinoblastoma is a childhood ocular tumor rapidly developing from the immature cells of the retina due to loss of functional retinoblastoma protein. Digoxin, a cardiac glycoside, has been reported to be effective in inducing apoptosis, cell cycle arrest, and cytotoxic effects on human cancers. In this regard, the present study aims to investigate whether digoxin could suppress retinoblastoma cancer through the regulation of transforming growth factor-β (TGF-β) signaling pathway. Methodology: The effects of digoxin on Y-79 cells, retinoblastoma cancer cell line, were investigated using MTT (3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazoli-umbromide) and BrdU (bromodeoxyuridine) assays to measure cellular cytotoxicity effects and cell apoptosis, respectively. Also, a qPCR assay was employed to analyze the mRNA expression levels of TGFβ signaling pathway including C-MYC, P21, P15, TGFβRI, TGFβRII, and SMAD2, 3, and 4 genes. Results: The results of the cell function assays revealed that digoxin inhibited the cell viability and proliferation of Y-79 cells. In addition, it was found that digoxin significantly suppressed C-MYC expression and enhanced the expression of P21, P15, SMAD2 and SMAD4 genes in a dose-and time-dependent manner. However, the obtained results could not detect any significant effect of digoxin on TGFβRI, TGFβRII and SMAD3 genes. Conclusion: Taken together, the findings of the present study suggest that digoxin could be a potential therapeutic agent in the treatment of retinoblastoma by regulating the cell cycle genes via a non-canonical TGF-β signaling pathway

Dosimetric Investigation of Six Ru-106 Eye Plaques by EBT3 Radiochromic Films and Monte Carlo Simulation

Background: Ophthalmic brachytherapy using radioactive plaques is an effective technique for the treatment of uveal melanoma. Ru-106 eye plaques are considered as interesting issue due to their steep gradient dose. The pre-planning evaluation of dosimetric parameters is essential for the treatment planning system.Objective: The current study aims at providing dose distributions of six Ru-106 eye plaques (CCA, CCB, CGD, CIB, COB and COD) using radiochromic EBT3 film, Geant4 Monte Carlo toolkit and the treatment planning software (Plaque Simulator).Material and Methods: In this experimental study, an in-house phantom was employed for depth dose measurements with EBT3 films. Also, Geant4.10.5 scoring mesh was implemented to obtain the 2D dose distribution of the plaques. The results were compared with Plaque Simulator software and the manufacturer’s (BEBIG) data. The gamma index criterion (3%/3 mm) was used to evaluate dose distributions obtained by the film measurements and Geant4 simulation.Results: A good agreement was achieved between simulation and experimental results. Gamma index passing rate was 94.2%, 89.3%, 88.2%, 82.2%, 92.2% and 90.1% for CCA, CCB, CGD, CIB, COB and COD plaques, respectively. Absolute dose rate (mGy/min) obtained by EBT3 film at the depth of 2 mm was 79.4 mGy/min, 81.0 mGy/min, 78.6 mGy/min, 62.2 mGy/min, 75.2 mGy/min and 81.2 mGy/min for CCA, CCB, CGD, CIB, COB and COD plaques, respectively.  Conclusion: The measured dose distributions and lateral dose profiles may be utilized in the treatment planning system to cover clinical volumes such as the clinical target volume and the gross tumor volume

Massive Uveal Relapse of Retinoblastoma Presumed to Be Choroidal Tumorous Involvement: Case Series

We report the choroidal and ciliary body invasion by retinoblastoma (RB) in a salvaged eye after complete and successful primary treatment. Case 1: A 25-month-old boy was referred due to group B RB lesions based on the International Classification of RB (ICRB; groups A–E) in the right eye (OD). His left eye (OS) was enucleated because of advanced group E RB. After 47 months of uneventful follow-up (F/U), a new lesion recurred and was treated with transpupillary thermotherapy. Four months later, a fast-growing pigmented subretinal mass was detected that was treated by brachytherapy with the apical dose of 80 Gy. Three weeks later, the lesion regressed completely, and no recurrence happened after 6 years of F/U. Case 2: A 4-month-old girl with a deletion in chromosome 13 was referred for bilateral RB. OD was enucleated because of unresponsive RB and anterior segment involvement. In OS, group B lesions had multiple recurrences after systemic chemotherapy. After a while, a single mass appeared in the nasal periphery which was controlled well with brachytherapy. Four months later, AC involvement was controlled with IAC, intravitreal, and intracameral chemotherapy, but posterior synechia and cataract appeared later. One year after the last treatment, UBM showed a ring-shaped ciliary body mass. Her parents refused enucleation again, and she received intravenous chemotherapy. Two years later, magnetic resonance imaging showed orbital and optic canal involvement with a deformed globe. In conclusion, RB recurrence can appear as local choroidal and ciliary body involvement even after a time of complete remission. The role of B-scan and UBM in early diagnosis and successful treatment is valuable

Intraocular Injection of Stivant® (A Biosimilar to Bevacizumab): A Case Series

Purpose: To report the results of intravitreal injection of a bevacizumab biosimilar called Stivant®. Methods: This prospective interventional case series was conducted on eyes with neovascular age-related macular degeneration (nAMD), retinal vein occlusion (RVO), and diabetic macular edema (DME). Stivant® was injected in three consecutive months and changes in best-corrected visual acuity (BCVA) and central macular thickness (CMT) were measured at baseline and monthly up to one month after the third injection. Results: Three hundred and eighty-five eyes with DME (234 eyes, 61%), nAMD (87 eyes, 22%), and macular edema secondary to RVO (64 eyes, 17%) were enrolled. The mean ± standard deviation age of the patients was 61.7 ± 7.20 years. The mean BCVA and CMT changed from 0.63 ± 0.3 to 0.51 ± 0.3 LogMAR (P = 0.12 ) and from 420.4 ± 47.3μm at baseline to 316.7 ± 50.6 μm (P &lt; 0.001) in the DME group; from 0.79 ± 0.3 to 0.68 ± 0.3 LogMAR (P = 0.19) and from 376.1 ± 31.7 μm to 303 ± 31.3 μm (P = 0.019) in the nAMD group; and from 0.81 ± 0.4 to 0.63 ± 0.4 LogMAR (P = 0.05) and from 424.21 ± 18 μm to 303.4 ± 18.8 μm (P &lt; 0.001) in the RVO group, respectively. Conclusion: Our limited experience showed that the intravitreal injection of Stivant® was well tolerated. Although the results of this case series showed relative improvement in CMT one month after the last injection of Stivant®, BCVA improvement was statistically significant only in the RVO group. This would be essential to design a randomized clinical trial to evaluate the non-inferiority of Stivant® in comparison to bevacizumab