With the advent of small-gauge vitrectomy, there has been a paradigm shift in the surgical management of posterior segment disorders. However, when this concept was first introduced, there were numerous technical hurdles and limitations. Over the years, various technological advances, especially the introduction of new generation vitrectomy machines capable of powering small-gauge instrumentation and improvised fluidics, have overcome these limitations. This review presents the evolution of sutureless vitrectomy to its present status and discusses the various advances that have taken place in various concepts, such as instrumentation, to achieve better efficiency and results. Shorter operating times, improvements in patient comfort, and faster visual recovery are the main benefits of this approach.

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Purpose: Using the Titmus stereo test to examine the association between hyperopic ametropia including hyperopia, astigmatism, anisometropia, and stereoacuity in a school-aged population. Methods: We measured cycloplegic autorefraction, best corrected monocular visual acuity and best corrected stereoacuity in a population of 4- to 13-year-old school-aged children (Keelung, Taiwan) after obtaining proper informed consent. Children with amblyopia (best-corrected visual acuity inferior to 20/25) or strabismus were excluded from the study. The effects of the severity of hyperopia, astigmatism, and anisometropia on stereoacuity revealed by the Titmus stereo test were analyzed. Results: One hundred and seventeen children (51 boys and 66 girls; mean age = 7.32 years, range = 4–13 years) with hyperopia were enrolled into the study. The mean spherical error was +1.48 ± 1.30 diopters (D) (range = +0.25 to +6.50D). The mean astigmatism was −1.22 ± 1.04 D (range = 0 to −3.50 D). They received the Titmus stereo test. A spherical error > +3.00 D and spherical equivalent > +3.00 D showed a strong association with decreased stereoacuity in the Titmus stereo test (p= 0.000). The degree of astigmatism or astigmatic anisometropia was not significantly correlated with the stereopsis in the test. Conclusion: The Titmus stereo test revealed a good quantification of the stereoacuity. A spherical error > +3.00 D, and a spherical equivalent > +3.00D were all associated with a significantly reduced stereoacuity in school-aged children.

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Bleb-related infection is a potentially sight-threatening complication of glaucoma filtration surgery. Here, we describe its clinical features and management. Blebitis, or stage I infection, is a mild form of bleb-related infection. The prognosis of blebitis is usually good, unless it has progressed to later stages. Endophthalmitis, or stage II or stage III infection, however, is a much-advanced stage of the infection and has a poorer prognosis. For treatment of bleb-related infections, immediate intensive antibacterial treatment is urgently required.

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Purpose: This study investigated the changes of refractive status in both phakic and pseudophakic eyes after pars plana vitrectomy (PPV) surgery without scleral buckling or silicone oil tamponade, and examines the possible factors that may affect the refractive changes. Methods: A retrospective case note review of 172 eyes (172 patients) undergoing PPV surgery for a variety of vitreoretinal conditions. Refractive status was measured before and after vitrectomy surgery in 60 eyes after the application of inclusion and exclusion criteria. Refractive status before and after PPV was analyzed using paired t-tests. An independent t-test and analysis of variance were subsequently conducted to analyze any significant differences in refractive change under a variety of etiological factors. Changes in refraction were also analyzed using a linear regression model. Results: A total of 60 eyes from 60 consecutive patients were included in this study. The mean spherical equivalence (SE) before PPV was 0 diopters (D), and −1.21 D after PPV. The mean change of SE was −1.21 D (95% confidence interval −1.70 to −0.71 D, p < 0.001). The mean astigmatism (cylinder) power before PPV was −1.17 D, and was −1.23 D after PPV. The mean change of astigmatism was −0.06 D (p = 0.753). There was no significant difference in refractive change between gender, age groups, disease categories, and use of gas tamponade. There was a significant difference between the phakic and pseudophakic groups (p = 0.047). The mean change of SE in 37 phakic eyes was −1.60 D (95% confidence interval −2.35 to −0.85 D, p < 0.001), and in 23 pseudophakic eyes it was −0.59 D (95% confidence interval −0.99 to −0.18 D, p = 0.007). Conclusions: Significant changes in refractive status were observed in patients undergoing PPV. Most of the patients experienced a myopic shift, among both phakic (−1.60 D) and pseudophakic (−0.59 D) patients. Changes in astigmatism were not significant. There are several plausible explanations; however, the true underlying etiologies of the refractive change are to be further investigated. To our knowledge, this is the first refractive study conducted after PPV among the Taiwanese population.

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Purpose: This work was conducted in order to study the intraocular lens (IOL) power predictability of formulas provided by the American Society of Cataract and Refractive Surgery (ASCRS) website for patients who had undergone myopic laser refractive surgery. Methods: In this retrospective study, we analyzed 11 eyes (from nine patients) that had previously undergone myopic laser-assisted in situ keratomileusis or photorefractive keratectomy and experienced subsequent phacoemulsification and posterior-chamber IOL implantation. Using the adjusted central K (keratometry), axial length, and the SRK/T formula, we compared the original desired refraction to the manifest refraction 1 month after cataract surgery. According to the postoperative manifest refraction, we compared the IOL power calculated using the different methods on the ASCRS website. Results: Before cataract surgery, the mean adjusted central K reading was 35.90 diopters (D) (range 29.24– 41.58 D), and the mean axial length was 28.53 mm (range 25.77–32.79 mm). Postoperatively, the mean arithmetic refractive prediction error was 0.50 D (range −1.72 D to 2.33 D), and the mean absolute error was 1.07 D (range 0.01–2.33 D). The most reliable method was the Masket method in combination with the double K Holladay I formula. The predictability of the adjusted central K method and the Masket method in combination with the single-K SRK/T formula was as precise as that of the modified Masket method in combination with the double K Holladay I formula and the Shammas method in combination with the Shammas-PL formula. Conclusion: ASCRS offers the use of a postrefractive IOL calculator online, free of charge. The Masket method in combination with the double K Holladay I formula is the best choice for IOL power prediction after laser-assisted in situ keratomileusis or photorefractive keratectomy surgery. The adjusted central K method is a convenient and effective strategy with which to correct central corneal power. However, double K formulas designed for adjusted central K should be used for more accurate predictions of lens position.

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Purpose: To elucidate the effects of tumor necrosis factor (TNF)-α on the expression of inducible nitric oxide synthase (iNOS) in retinal pigment epithelial cells in vitro. Methods: ARPE-19 cell lines were cultured with TNF-α stimulation, and then treated with proteasome inhibitors (MG132 or lactacystin) for 30 minutes. The expression of iNOS was determined by RT-PCR and Western blot. The expression of nitric oxide (NO) was determined by an enzyme-linked immunosorbent assay. The interaction of nuclear factor kappa-B (NF-κB) activation and iNOS induction was assessed by electrophoretic mobility shift assay. Results: The expression of iNOS in ARPE-19 was induced by TNF-α in a dose-dependent manner. Upregulation of iNOS resulted in increased production of NO. iNOS induced by TNF-α could be inhibited by MG-132 and lactacystin. Supershift assay revealed that NF-κB activation was responsible for iNOS induction. Conclusion: TNF-α could induce iNOS expression and NO production in RPE cells, at least in part, via an NF-κB signal pathway.

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A 29-year-old male experienced abrupt visual loss in the left eye following an elastic cord rebounding injury that resulted in ocular hypotony. He received topical atropine and prednisolone eye drops for more than one month without improvement. On examination, his visual acuity was 1.0 OD and counting fingers at 80 cm OS. Initial intraocular pressure (IOP) was 15 mmHg OD and 6 mmHg OS. Gonioscopic evaluation of his left eye revealed a cyclodialysis cleft positioned between 6 and 7 o’clock. A fundus photograph showed signs of hypotony maculopathy including optic disc edema, tortuous vessels, and chorioretinal folds. B-scan ultrasound displayed choroidal thickening and optical coherence tomography (OCT) demonstrated macular edema, subretinal fluid, retinal striae, and choroidal folds. Pars plana vitrectomy and sulfur hexafluoride (SF₆) tamponade were performed. After gas absorption, IOP was 11 mmHg OS and remained steady during follow-up. One week after surgery, his visual acuity improved to 0.9. The present case highlights that pars plana vitrectomy with gas tamponade is worth considering for patients with cyclodialysis cleft associated with hypotony maculopathy. Early surgical intervention remains the treatment of choice when hypotony maculopathy and deteriorated vision are noted. Conservative management may be suitable in cases when visual function is not impaired.

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Herein, we report a case presenting with the optic disc pit and optic nerve cyst coexistence. A 54-year-old female presented to our office with progressive blurred vision for up to 3 months in her left eye. Upon examination, the best corrected visual acuity in the right eye was 20/20 and in the left eye was 20/ 100. Fundoscopic examination revealed a black pit at the temporal margin of left optic disc without obvious macular edema. Findings were confirmed later with optical coherence tomography (OCT) examination. Further magnetic resonance imaging (MRI) disclosed a well defined 6 mm × 6mm cystic lesion located at temporal aspect of left retro-bulbar optic nerve within the optic nerve sheath. Compression of left optic nerve was prominent. Visual evoked potential (VEP) test verified dysfunction of left optic nerve. She kept following up for 6 months. Neither maculopathy nor retinal edema occurred during this period. The visual acuity maintained 20/100 in her left eye. The size and location of optic disc pit remained as well. To sum up, in a patient with visual impairment combing with optic disc pit, further imaging surveys should be considered to exclude the possible coexistence of other optic nerve abnormalities.

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