A Novel Device for Suprachoroidal Drug Delivery to Retina: Evaluation in Nonhuman Primates.

Purpose: Evaluation of distribution and tolerance of suprachoroidal injection of indocyanine green (ICG) in nonhuman primates (NHPs) using a novel suprachoroidal (SC) delivery technology. Methods: Three live and three euthanized African green monkeys were injected with 150 or 200 µL ICG/eye into the SC space of both eyes, 2.5 mm posterior to the limbus in the inferior quadrant, utilizing a novel SC injector. Eyes were analyzed by imaging of scleral flatmounts. Live animals were observed for 24 hours for general health. Ophthalmic evaluation included slit-lamp biomicroscopy, tonometry, fundus imaging, confocal laser ophthalmoscopy, and spectral-domain optical coherence tomography (SD-OCT) before and at 10 minutes and 1, 3, and 24 hours post-injection. Results: SC dosing was successfully performed in all eyes. Infrared fundus imaging demonstrated ICG distribution throughout the posterior segment, reaching the macula within 24 hours post-injection. No inflammation, intravitreal penetration, SC blebs, retinal detachment, or hemorrhages were detected. No significant changes were observed in retinal thickness by SD-OCT (P = 0.267, ANOVA). A mild, statistically insignificant elevation in intraocular pressure was observed within 10 minutes post-injection (mean ± standard error: 7.28 ± 5.09 mmHg; P = 0.061) and was spontaneously resolved within the first hour after dosing. Conclusions: Suprachoroidal injection of 150 to 200 µL ICG dye was successfully performed and well tolerated in NHP eyes, with rapid distribution into the macular region and throughout the posterior pole. Translational Relevance: This novel SC drug delivery system may potentially provide safe and effective delivery of therapeutics to the posterior pole region in humans.

Suprachoroidal delivery of bevacizumab in rabbit in vivo eyes: Rapid distribution throughout the posterior segment.

PURPOSE: To test the in-vivo bio-distribution and safety of bevacizumab delivery into the suprachoroidal space (SCS) using a novel injection system in a large eye model. METHODS: Bevacizumab (1.25 mg) was injected into the vitreous (IVT, 50 µL, n = 12) or the SCS, (150 µL, n = 37) of live rabbits. Immunofluorescence and ELISA were used to assess bevacizumab distribution. Intraocular pressure (IOP) measurements, SD-OCT and fundus imaging, electroretinogram, and histology analysis were performed for safety assessment. RESULTS: Bevacizumab was observed throughout the choroid layers up to the retinal pigment epithelium (RPE), within 1 h following SCS injection. The Cmax of bevacizumab in the retina/choroid was 1043 ± 597 µg/gr tissue (mean ± standard error), 40-fold higher than in IVT injected eyes (p = 0.0339). One day following SCS injection, bevacizumab was detected throughout the posterior pole with a two-fold lower concentration. One week post-SCS injection, bevacizumab concentration in the retina/choroid dropped to 2.36 ± 1.32 µg/gr tissue (p = 0.034 vs. 1 h), with a half-life of 20 h. No suprachoroidal blebs, retinal detachment, hemorrhages, inflammation or changes in retinal function were observed up to 2 months following SCS injection. Elevated IOP (+16 mmHg) was observed two minutes post-SCS injection and spontaneously returned to baseline levels within 10 minutes. CONCLUSIONS: The novel injection system enabled a minimally invasive, safe, and consistent delivery of bevacizumab with rapid distribution throughout the choroid layers up to the RPE in large eyes. Large volumes of anti-angiogenic are delivered in close proximity to the retina due to the high volume distribution.

A 12-month prospective study to evaluate the efficacy of using the treat-and-extend regimen with intravitreal aflibercept as a Second-Line Treatment for Diabetic Macular Oedema (the TADI Study).

PURPOSE: To evaluate the efficacy of intravitreal aflibercept as a second-line therapy in eyes with persistent diabetic macular oedema (DMO) despite receiving initial bevacizumab treatment. METHODS: A prospective multicentre study was conducted in nine academic clinics in Israel. Starting from the first follow-up visit, a treat-and-extend regimen was applied in which the treatment intervals were extended by 2 weeks based on macular thickness using SD-OCT. The primary outcome was central subfield thickness (CST) at week 52. RESULTS: Forty-four patients (n = 48 eyes) were recruited to the study, and 43 eyes completed 52 weeks of follow-up. Patients received a mean (±SD) of 7.9 ± 3.5 bevacizumab injections before enrolment. The mean (±SD) CST under aflibercept therapy decreased from 468 ± 131 µm at baseline to 303 ± 67 µm at 52 weeks (p = 0.002), and best corrected visual acuity improved from 64 ± 15 ETDRS letters at baseline to 75 ± 8 letters at week 52 (p = 0.001). Twenty (46%) eyes met the treat-and-extend criteria and received a mean (±SD) of 10.9 ± 2 aflibercept injections. CONCLUSIONS: Eyes with persistent DMO following initial bevacizumab therapy had a marked reduction in macular thickness and improved visual acuity following 1 year of treatment with intravitreal aflibercept. Less than half of the patients met eligibility criteria for extension of the treatment interval; for these patients, the treat-and-extend regimen resulted in a maximum treatment interval of 10 weeks during the first year.

Minimally Invasive Technique for Choroidal Fluid Drainage.

BACKGROUND: This study describes a simple technique for the treatment of kissing choroidal detachment. In contrast to the commonly used technique, this technique is minimally invasive, fast, sutureless, and does not require access to the vitreous space. METHODS: A maintainer is inserted into the anterior chamber. A 25G trocar is inserted at the pars plana into the suprachoroidal space. Drainage is evident by the clear yellowish fluid freely emerging through the trocar, accompanied with deepening of the anterior chamber and an increase in the red reflex. RESULTS: Follow-up ultrasound 1 week after the surgery demonstrated resolution of the choroidal detachment. Net surgery time is about 10 minutes. No complications were noted. DISCUSSION: This is the first report of the technique performed in phakic eye, with video description of the steps and real-time clues for successful drainage even with reduced posterior segment visibility due to lens opacities.

PERSISTENT LOCULATED SUBRETINAL FLUID AFTER RHEGMATOGENOUS RETINAL DETACHMENT SURGERY.

PURPOSE: To identify factors associated with persistent subretinal fluid (SRF) after small-gauge pars plana vitrectomy for primary rhegmatogenous retinal detachment. METHODS: This retrospective study included patients from 2 tertiary centers who underwent pars plana vitrectomy for repair of rhegmatogenous retinal detachment between 2013 and 2016. Preoperative and intraoperative parameters were examined for association with development of SRF. RESULTS: Overall, 153 eyes of 153 patients, mean age of 55.2 ± 17.9 years were included. Persistent SRF occurred in 15.0% (n = 23) and was associated with high myopia (65.22 vs. 26.15%, P < 0.001), macula-involving retinal detachment (91.30 vs. 66.15%, P = 0.02), phakic lens status (86.96 vs. 66.15%, P = 0.04), and younger age (47.8 ± 18.7 vs. 56.5 ± 17.5, P = 0.04) while drainage retinotomy was protective (13.04 vs. 34.11%, P = 0.04). In multivariate analysis, high myopia (P = 0.009) and macula-involving retinal detachment (P = 0.004) were associated with SRF, while drainage retinotomy was protective (P = 0.03). Persistent SRF was associated with outer retinal band irregularity (30.4 vs. 9.3%, P = 0.005). There were no significant differences in terms of change in best-corrected visual acuity from presentation (P = 0.70), or final best-corrected visual acuity (P = 0.54). CONCLUSION: Eyes with preoperative high myopia and macular involvement, and those in which a drainage retinotomy was not performed, were more likely to develop persistent SRF.

INCIDENCE AND RISK FACTORS FOR HYPOTONY AFTER 25-GAUGE PARS PLANA VITRECTOMY WITH NONEXPANSILE ENDOTAMPONADE.

PURPOSE: The purpose of this study was to assess the incidence and risk factors for early postoperative hypotony after 25-gauge pars plana vitrectomy with nonexpansile endotamponade. METHODS: A retrospective study of consecutive patients who underwent 25-G pars plana vitrectomy. Hypotony was defined as an intraocular pressure of 5 mmHg or less after surgery and ocular hypertension as an intraocular pressure greater than 21 mmHg. RESULTS: Overall, 307 eyes of 307 patients with a mean age of 61.7 ± 14.3 of which 56.7% were males were included. Hypotony was identified in 5.2% of cases (n = 16) at Day 1 and 0.7% (n = 2) at Week 1 with no hypotony-related complications. The hypotony group had a higher number of previous vitreoretinal surgeries (1.5 ± 1.1 vs. 0.4 ± 0.7, P < 0.001) and a higher prevalence of preoperative ocular hypertension (22.2% vs. 4.8%, P = 0.02), pseudophakia (77.8% vs. 48.4%, P = 0.01), silicone oil removal (61.1% vs. 8.3%, P < 0.001), and external diathermy performed (55.6% vs. 20.1%, P = 0.001). In stepwise multivariate analysis, significant parameters were silicone oil removal (R = 16.34%, odds ratio 13.45, P < 0.001), pseudophakia (R = 5.69%, odds ratio 3.65, P = 0.03), and younger age (R = 2.68%, odds ratio 0.96, P = 0.04). CONCLUSION: Silicone oil removal is a significant risk factor for early postoperative hypotony after 25-G pars plana vitrectomy.

Patients' Experience of Anxiety and Pain during Retrobulbar Injections prior to Vitrectomy.

PURPOSE: The purpose of this study was to evaluate the correlation between pain associated with retrobulbar block and anxiety levels before the injection. METHODS: This prospective observational, noninterventional study included consecutive patients who received a retrobulbar block by a single surgeon prior to undergoing 25G PPV at the Department of Ophthalmology, Rambam Health Care Campus, between April 2016 and August 2017. Patients plotted their anxiety levels (scale 0-10) using the visual analogue scale for anxiety (VASA), and immediately after receiving the injection, they plotted their experienced level of pain (scale 0-10) using the visual analogue scale for pain (VAS), with scores ≥7 defined as severe. RESULTS: Overall, 48 eyes of 48 patients aged 68.4 ± 10.3 years were included, of which 62.5% were of male gender. Severe anxiety and pain were experienced by 10.4% and 12.5%, respectively. There was a significant correlation between VASA and VAS scores (r = 0.43, p=0.002) with no other preprocedural parameters demonstrating a significant association with the VAS score. In multivariate analysis, the VASA score was the only factor that was significant (p=0.01), and a patient with a severe VASA score was 20 times more likely of experiencing severe pain (p=0.006). The ROC curve analysis revealed an area under the curve of 0.89 (p < 0.001), and a VASA score >4 demonstrated a sensitivity of 83.3% and a specificity of 73.8% in predicting severe pain. CONCLUSIONS: Approximately 10% of patients experience severe anxiety and pain during retrobulbar blocks. Considering the importance of compliance, reducing anxiety and premedication may be considered, particularly in high-risk patients (VASA score > 4).

International multi-center study of iatrogenic retinal tears in pars plana vitrectomy.

AIM: To study and compare the effect of different surgical settings on the development of iatrogenic retinal tears (IRT) in conventional (20-gauge) and microincisional vitrectomy. METHODS: An international retrospective comparative study of 394 patients who had simple vitrectomy at three tertiary centers. Surgeries were performed by four retina surgeons using different viewing systems. Two groups of eyes were compared: microincisional vitrectomy (327 eyes) and conventional (67 eyes) vitrectomy. An iatrogenic tear was defined as the occurrence of one or more peripheral retinal tears during surgery or at any visit in the first 6wk postoperatively. RESULTS: Mean age was 67±12y and 55% were female. Iatrogenic tears occurred in 11/394 (2.8%) of eyes. The rate of tears was similar among different surgeons and viewing systems (P=0.93 and P=0.76, respectively). Surgical indication, preexisting pseudophakia/aphakia, induction of posterior vitreous detachment (PVD) during surgery, and the use triamcinolone acetonide didn't significantly affect the rate of tears (P>0.1 for all factors). A higher rate of tears was found in the conventional group compared to the microincisional group (respectively, 7.5%, 1.8%, P=0.02). CONCLUSION: The rate of IRT in vitrectomy is not significantly affected by surgical indication, preexisting PVD or pseudophakia, or use of triamcinolone or different viewing systems but is significantly higher in conventional vitrectomy. Microincisional platforms improve the safety of vitrectomy regardless of the viewing system used.

Sulfur Hexafluoride (SF6) versus Perfluoropropane (C3F8) in the Intraoperative Management of Macular Holes: A Systematic Review and Meta-Analysis.

PURPOSE: A systematic literature search was conducted to identify and review studies comparing SF6 to C3F8 as a tamponade agent in the intraoperative management of macular holes. METHODS: Publications up to October 2018 that focused on macular hole surgery in terms of primary closure, complications, and clinical outcomes were included. Forest plots were created using a weighted summary of proportion meta-analysis. Analysis was performed separately for SF6 and C3F8. A random effects model was used, and corresponding I 2 heterogeneity estimates were calculated. RESULTS: Nine pertinent publications studying a total of 4,715 patients were identified in 2000 to 2017, including two randomized studies (n=206), two prospective studies (n=170), and five retrospective or registry-based studies. Similar rates of closure between SF6 and C3F8 were reported in eight out of nine studies, regardless of subgroup analyses. All studies reporting visual outcomes showed similar results when comparing SF6 to C3F8 at one to six months of follow-up. Neither agent was clearly associated with increased risk of ocular hypertension, cataract formation, or other adverse events. Meta-analytic pooling of the closure rates in the SF6 group resulted in 91.73% (95% confidence interval: 88.40 to 94.55, I 2: 38.03%), and for C3F8, the closure rate was 88.36% (95% confidence interval: 85.88 to 90.63, I 2: 0.0%). CONCLUSIONS: Both SF6 and C3F8 appear to have achieved similar visual outcomes and primary closure rates and neither was associated with an increased risk of adverse events. Considering the more rapid visual recovery with SF6, there appears to be no evidence to support C3F8 as the tamponade agent of choice for macular hole surgery.

Diabetic macular edema treated with ranibizumab following bevacizumab failure in Israel (DERBI study).

PURPOSE:: To evaluate the outcome of second-line intravitreal ranibizumab treatment in eyes with diabetic macular edema having persistent edema following initial therapy with intravitreal bevacizumab. METHODS:: Diabetic macular edema treated with ranibizumab following bevacizumab failure in Israel was a retrospective, multi-center study. Consecutive eyes with persistent diabetic macular edema following at least three previous intravitreal bevacizumab injections prior to intravitreal ranibizumab, at least three-monthly intravitreal ranibizumab injections and at least 12 months of follow-up were included. Data collected included demographics, ocular findings, diabetes control, details of intravitreal bevacizumab and ranibizumab injections, and visual and anatomical measurements before and after intravitreal ranibizumab treatment. RESULTS:: In total, 202 eyes of 162 patients treated at 11 medical centers across Israel were included. Patients received a mean (±standard deviation) of 8.8 ± 4.9 intravitreal bevacizumab injections prior to the switch to intravitreal ranibizumab. A mean of 7.0 ± 2.7 intravitreal ranibizumab injections were given during the 12 months following the switch to intravitreal ranibizumab. The median central subfield retinal thickness (±interquartile range) by spectral-domain optical coherence tomography decreased from 436 ± 162 µm at baseline to 319 ± 113 µm at month 12 (p < 0.001). Median logMAR visual acuity (±interquartile range) improved from 0.40 ± 0.48 at baseline to 0.38 ± 0.40 at month 12 (p = 0.001). Linear regression suggested that higher number of intravitreal ranibizumab injections and higher pre-switch central subfield retinal thickness were associated with favorable visual outcome. Higher number of intravitreal bevacizumab injections and the presence of intraretinal fluid before the switch lessened the odds of favorable outcome. CONCLUSION:: Switching from bevacizumab to ranibizumab in persistent diabetic macular edema was associated with anatomical improvement in the majority of eyes and ⩾2 lines of vision improvement in 22% of eyes.

A Sema3C Mutant Resistant to Cleavage by Furin (FR-Sema3C) Inhibits Choroidal Neovascularization.

In age-related macular degeneration (AMD), abnormal sub retinal choroidal neovascularization (CNV) is a major cause of blindness. FR-sema3C is a point mutated form of semaphorin-3C that is resistant to cleavage by furin like pro-protein convertases (FPPC). We have found in previous work that FR-sema3C functions as an anti-angiogenic factor. In this study we investigated the possible use of FR-sema3C as an inhibitor of CNV. FR-sema3C inhibits VEGF as well as PDGF-BB signal transduction in endothelial cells and to less extent bFGF induced signal transduction using a mechanism that does not depend upon the binding of VEGF like the drugs that are currently the mainstay treatment for AMD. CNV was induced in eyes of C57 black mice by laser photocoagulation. Intravitreal injection of FR-Sema3C or aflibercept (VEGF-trap) was then used to inhibit CNV formation. Invading choroidal vessels were visualized a week later by injection of FITC-dextran into the circulation, followed by the measurement of the area of the invading blood vessels. Injection of 0.1 µg FR-Sema3C inhibited CNV by 55% (P<0.01) and was as effective as 5 µg aflibercept. FR-sema3C did not display any adverse effects on retinal function following its injection into eyes of healthy mice as assessed by optokinetic reflex (OKR) and Electro-retinogram (ERG) criteria. Furthermore, FR-sema3C did not induce apoptosis in the retina as determined by TUNEL nor was there any discernable structural damage to the retina as assessed by several immuno-histochemical criteria. Our results suggest that FR-sema3C could perhaps be used for the treatment of AMD, and that it may perhaps be of benefit to patients that do not respond well to current treatments relying on VEGF sequestering agents.

A SEMA3E mutant resistant to cleavage by furins (UNCL-SEMA3E) inhibits choroidal neovascularization.

Abnormal subretinal choroidal neovascularization (CNV) is a major cause of blindness in exudative age-related macular degeneration (AMD). Current anti-angiogenic treatments by VEGF sequestering agents have been successful, but a significant proportion of patients do not respond well to these treatments, and the response of others diminishes over time, suggesting that additional anti-angiogenic agents that function by separate mechanisms may be of use to such patients. We have previously found that a point mutated form of semaphorin-3E resistant to cleavage by furin like pro-protein convertases (UNCL-Sema3E) displays potent anti-angiogenic properties. We therefore determined if UNCL-Sema3E has potential as an inhibitor of CNV formation. We chose to study UNCL-Sema3E rather than wild type sema3E because unlike full length sema3E, the major p61-Sema3E peptide that is produced by cleavage of sema3E with furin like pro-protein convertases activates signal transduction mediated by the ErbB2 receptor and can promote tumor metastasis in addition to its anti-angiogenic activity. UNCL-Sema3E inhibited efficiently vascular endothelial growth factor-A (VEGF), platelet derived growth factor (PDGF) and basic fibroblast growth factor (bFGF) signaling in human umbilical vein derived endothelial cells (HUVEC) and to a lesser extent hepatocyte growth factor (HGF) signal transduction. CNV that was induced in the eyes of C57 black mice by laser photocoagulation was inhibited by 65% (P < 0.01) following a single bolus intra-vitreal injection of 5 µg UNCL-Sema3E. This inhibitory effect was similar to the inhibition produced by a single bolus intra-vitreal injection of 5 µg aflibercept. A similar inhibition of CNV was observed following the injection of UNCL-Sema3E into the eyes of Long-Evans rats. However, a higher dose of UNCL-Sema3E (125 µg), partially due to the larger volume of the vitreous cavity of rats, was required to achieve maximal inhibition of CNV. Injection of UNCL-Sema3E into eyes of healthy mice did not have any adverse effect on retinal function as assessed by optic kinetic reflex (OKR) or by electroretinogram (ERG) assays nor did UNCL-Sema3E injection affect the structure of the retina as determined using histology. To conclude, our results suggest that UNCL-Sema3E may be useful for the treatment of exudative AMD, which does not respond well to conventional anti-VEGF therapy.

Small-Gauge Pars Plana Vitrectomy With SF6 Gas for the Repair of Primary Rhegmatogenous Retinal Detachment With Multiple Breaks.

BACKGROUND AND OBJECTIVE: To compare outcomes of 25-gauge pars plana vitrectomy (PPV) and sulfur hexafluoride (SF6) gas for primary rhegmatogenous retinal detachment (RRD) associated with multiple-quadrant versus single-quadrant breaks. PATIENTS AND METHODS: A retrospective study of patients with RRD who underwent 25-gauge PPV with breaks involving multiple quadrants (Group A) or versus a single quadrant (Group B). RESULTS: One hundred eighteen eyes of 118 patients with a mean age of 60.4 years ± 11.8 years were reviewed, 27 with multiple-quadrant breaks and 91 with single-quadrant breaks. Single surgery anatomical success was achieved in 92.6% of Group A versus 93.4% of Group B patients (P = .88). The location and number of quadrants did not account for the variation in single surgery success or visual outcome. CONCLUSIONS: RRD with multiple-quadrant breaks is not associated with worst outcomes than single-quadrant breaks when treated with 25-gauge PPV and SF6 gas. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:820-827.].

Trends in Authorship of Articles in Major Ophthalmology Journals by Gender, 2002-2014.

PURPOSE: To evaluate trends in the prevalence of women authors in ophthalmology in recent years. DESIGN: Cohort study. PARTICIPANTS: Authors listed in publications of 6 leading ophthalmology journals between January 2002 and December 2014. METHODS: Using the PubMed search engine, we conducted an observational study of trends in gender distribution of all authors in 6 leading ophthalmology journals between January 2002 and December 2014. In multiauthored articles, the first listed author often is the lead investigator and the last author is the senior author. Therefore, the full names and positions (first, middle, or last) of all authors in every article were collected. A Google-based name identifier was used to assign the gender of authors. MAIN OUTCOME MEASURES: Proportion of women authors throughout the study period in all journals, general ophthalmology versus subspecialty journals, and basic science versus clinical research journals. Furthermore, we assessed the proportion of women in different authorship positions (first, middle, and last). RESULTS: A total of 102 254 authors from 23 026 published articles were analyzed. There was a significant rise over time in the percentage of women authors, with a steeper slope for first authors than for last authors (P<0.001), although in 2014, women authors were less than the 50% mark in all categories of authorship. The rise in the percentage of women authors was similar in basic and clinical research, but was steeper for first authorship than for last authorship (P<0.001). In all 3 authorship positions (first, middle, or last), women's contributions consistently were higher in basic research publications. The rise in the percentage of women authors was significantly steeper for general journals than for subspecialty journals (P<0.001). There was no significant rise for last authorship in subspecialty journals. In all 3 authorship positions, the proportion of women was consistently higher in general ophthalmology journals than for subspecialty journals. CONCLUSIONS: Despite an overall increase in the contribution of women to the field of ophthalmology, contributions to articles published in subspecialty ophthalmology journals and the proportion of women listed as last authors on overall articles published in ophthalmology journals are still low.

UNTREATED OBSTRUCTIVE SLEEP APNEA HINDERS RESPONSE TO BEVACIZUMAB IN AGE-RELATED MACULAR DEGENERATION.

PURPOSE: To compare functional and anatomical responses to intravitreal bevacizumab in patients with exudative age-related macular degeneration (AMD) between two groups of patients with obstructive sleep apnea (OSA) with and without treatment with continuous positive airway pressure therapy. METHODS: Patients with OSA were categorized into 2 groups: 18 untreated and 20 treated with continuous positive airway pressure therapy. All patients had exudative AMD and received treatment with intravitreal bevacizumab. Central retinal thickness was plotted against time to assess anatomical response. Logarithm of the minimum angle of resolution visual acuity changes determined functional effect. Total number of intravitreal injections administered was assessed. RESULTS: Treated OSA group received 8 ± 7 total injections; untreated OSA group received 16 ± 4 injections (P < 0.05). Treated OSA group achieved statistically significant better visual acuity (logarithm of the minimum angle of resolution, 0.3 ± 0.24, 20/40), as opposed to the untreated group (logarithm of the minimum angle of resolution, 0.7 ± 0.41; P < 0.05). Central retinal thickness improved in the treated OSA group compared with the untreated group: 358 ± 95 µm to 254 ± 45 µm and 350 ± 75 µm to 322 ± 105 µm, respectively (P < 0.05, 20/100). CONCLUSION: Untreated OSA hinders the response of exudative AMD to intravitreal bevacizumab. Treatment of OSA with continuous positive airway pressure therapy yields a subsequent anatomical response and functional improvement while requiring significantly less injections. Identifying and treating underlying OSA earlier in patients with exudative AMD may yield better functional outcomes.

25-GAUGE PARS PLANA VITRECTOMY AND SF6 GAS FOR THE REPAIR OF PRIMARY INFERIOR RHEGMATOGENOUS RETINAL DETACHMENT.

PURPOSE: To compare anatomical and functional outcomes of 25-gauge pars plana vitrectomy (PPV) and sulfur hexafluoride gas between inferior and superior rhegmatogenous retinal detachment (RRD). METHODS: A retrospective cohort study of patients with RRD who underwent 25-gauge PPV. Group A consisted of patients with an identified inferior retinal break (4-8 o'clock hours). Group B consisted of patients with an identified superior retinal break. RESULTS: Overall, 59 eyes of 59 patients with a mean age of 60.0 ± 12.3 years were included, with 57.6% being males; 25 with inferior breaks (Group A) and 34 with superior breaks (Group B). The mean follow-up time was 4 months (range 2-16 months). Single-surgery anatomical success was achieved in 96% (24/25) of Group A and 82.4% (28/34) of Group B patients (P = 0.22) with final anatomical success achieved in all cases. In regression analysis, break location (superior versus inferior) did not significantly account for the variation in single-surgery success or visual outcomes. CONCLUSION: Favorable results were achieved using 25-gauge vitrectomy and sulfur hexafluoride gas for primary RRD treatment. No differences in anatomical and functional success rates were observed between inferior and superior retinal break-associated RRD.

Focusing the surgical microscope.

A well-focused operating microscope addresses several needs that are all secondary to the surgeon's need to see clearly at all times. These needs include: the assistant; the sharpness of the video and monitor; as well as field of view, asthenopia, and focusing issues related to zoom, accommodation, and presbyopia. We provide a practical approach to achieve optimal focus that we call the sloping paper calibration method.

Twenty-five-gauge vitrectomy for the removal of 5000 centistokes silicone oil.

PURPOSE: To compare the safety and efficacy of removing 5000 centistokes silicone oil between 20-gauge and 25-gauge vitrectomy technique. METHODS: Prospective case series of 34 consecutive patients undergoing 5000 centistokes silicone oil removal using 20-gauge or 25-gauge cannulas. The main outcome measures were the safety and efficacy of silicone oil removal. The safety was evaluated by recording intraoperative and postoperative complication rates, including bleeding, recurrence of retinal detachment, hypotony, choroidal detachment, corneal edema, endophthalmitis, vitreous hemorrhage, conjunctival injection, and subconjunctival hemorrhage. The efficacy was judged by the ability to attain the complete removal of silicone oil and the total surgical time to complete the procedure. RESULTS: Sixteen patients underwent 20-gauge vitrectomy for the removal of 5000 centistokes silicone oil between January 2008 and January 2010, and 18 patients underwent 25-gauge vitrectomy for the removal of 5000 centistokes silicone oil from January 2010 to August 2012. Silicone oil was successfully removed completely in all cases. Using 25-gauge vitrectomy to remove silicone oil was significantly more time efficient with the mean total surgical time of 25 ± 6 minutes compared with 42 ± 10 minutes in 20-gauge vitrectomy group (P < 0.05). There were no differences in the intraoperative or postoperative complication rates between the two groups. None of the patients developed postoperative recurrence of retinal detachment, hypotony, choroidal detachment, corneal edema, endophthalmitis, or vitreous hemorrhage. CONCLUSION: Twenty-five-gauge silicone oil removal is safe and effective. Surgical time is significantly reduced using sutureless 25-gauge sclerotomies. This may translate to cost reduction by decreasing time spent in the operating room.

Use of 25% sulfur hexafluoride gas mixture may minimize short-term postoperative hypotony in sutureless 25-gauge pars plana vitrectomy surgery.

BACKGROUND: The purpose of this study was to compare postoperative intraocular pressures and percentage of vitreous cavity gas fill one day following 25-gauge pars plana vitrectomy with 20% versus 25% sulfur hexafluoride (SF6) gas fill. METHODS: This was a retrospective review of 187 consecutive cases of 25-gauge pars plana vitrectomy with complete fluid/gas exchange. The main outcome measures included percentage of gas fill of the vitreous cavity and intraocular pressure on postoperative day one. RESULTS: Fifty eyes underwent 25-gauge pars plana vitrectomy with 20% SF6 tamponade and 137 with 25% SF6 tamponade. On postoperative day one in the 20% SF6 group, there were five (10%) patients with hypotony (intraocular pressure ≤ 5 mmHg) and none in the 25% SF6 group. Mean intraocular pressure was 9 ± 2.5 mmHg and 16.8 ± 2.4 mmHg for the 20% SF6 and 25% SF6 groups, respectively (P < 0.01). None of the patients had postoperative intraocular pressure > 23 mmHg. Mean vitreous cavity gas fill on postoperative day one was 70.7% ± 10% in the 20% SF6 group and 89.5% ± 2.2% in the 25% SF6 group (P < 0.01). There was no difference in the number of phakic patients needing cataract surgery between the groups. CONCLUSION: A slightly expansile concentration of 25% SF6 gas can be safely and beneficially used in 25-gauge vitrectomy surgery to increase the amount of gas fill in the vitreous cavity and prevent postoperative hypotony.