Primary objective: To evaluate the effect of tip bevel angulation on phacoemulsification efficiency and chatter. Research design: In vitro laboratory study. Methods and procedures: Formalin-soaked porcine lenses were divided into 2 mm cubes. 0.9 mm straight 0, 15, 30, 45 beveled degree tips were used with micropulse ultrasound (6 ms on and 6 ms off ). Power was set at 100%, vacuum levels were set at 500 mmHg; and aspiration rates were set at 50 mL/min. Efficiency (time to lens removal) and chatter (number of lens fragment repulsions from the tip) were determined. Main outcomes and results: Changing the bevel angulation on a straight 0.9 mm phacoemulsification tip had no significant effect on efficiency. A 45 degree bevel was the most efficient tip overall. Chatter was seen to be significantly higher with a 15 degree tip (ANOVA, P=.0046). Conclusions: Tip bevel angulation has little effect on phacoemulsification efficiency and chatter, especially when optimized parameters are used. Limitations of this study include use of only one ultrasound power modulation and hard nuclear material.

Objective To compare thermal profiles of new transversal ultrasound power modulation to torsional ultrasound in an artificial chamber and cadaver eye. Design Laboratory investigation. Methods John A. Moran Eye Center Laboratories, University of Utah, Salt Lake City, Utah, was the study setting. Temperature increase after 30 seconds was measured at the needle midshaft in an artificial chamber and at maximal friction point in a cadaver eye. Ellips FX (transverse) was tested at 100% power, as was Signature with micropulse settings (6 milliseconds on and off). OZil (torsional only) was tested at 100% power in the artificial chamber and cadaver eye. Runs were completed with aspiration blocked. Temperature was continuously measured on the phacoemulsification sleeve using a microthermistor probe connected to the BAT-10 multipurpose thermometer, with an accuracy of ±0.1°C. Results Transversal FX had a greater temperature increase than micropulse (p < 0.001) and torsional (p < 0.001). Micropulse had a greater temperature increase than torsional (p < 0.001). The cadaver eye had a greater temperature increase than the artificial chamber for torsional (p < 0.001). Conclusions Higher heat accumulation and potential for incisional burn occurred with the cadaver model than with the artificial chamber, suggesting the need for caution when using 100% torsional ultrasound with aspiration blocked. Transversal FX generated more heat than was reported originally. Further study is needed to determine the incidence of incisional burn with varied power settings for this new model. Micropulse generated more heat than previous reports, but the increased efficiency is likely to negate potentially increased incisional burn risk.

Purpose To evaluate the efficiency of peristaltic-based and venturi-based vacuums. Setting John A. Moran Eye Center Laboratories, University of Utah, Salt Lake City, Utah, USA. Design Experimental study. Methods Porcine lenses were hardened with formalin and cut into 2.0 mm cubes. Time to fragment removal (efficiency) and fragment bounces off the tip (chatter) were measured using a Signature machine with the ability to switch between peristaltic-based and venturi-based vacuum. Micropulse longitudinal and transversal ultrasound motions were tested. Results Venturi-based vacuum had increased efficiency and decreased chatter compared with peristaltic-based vacuum at lower vacuum levels. Conclusion Use of a venturi-based vacuum, when available, may result in reduced clearance time of lens material and mitigate chatter even under noisy conditions. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.

PURPOSE:To evaluate the effect of vacuum and aspiration rates on phacoemulsification efficiency. SETTING:John A. Moran Eye Center Laboratories, University of Utah, Salt Lake City, Utah, USA. DESIGN:Experimental study. METHODS:Formalin-soaked porcine lenses were divided into 2.0 mm cubes, and 0.9 mm 30-degree beveled 20-degree bent tips were used with micropulse ultrasound (US) (6 milliseconds on and 6 milliseconds off) and a peristaltic flow system. Vacuum levels were tested at 200, 300, 400, and 500 mm Hg, and aspiration rates were tested at 20, 35, and 50 mL/min. Efficiency (time to lens removal) and chatter (number of lens fragment repulsions from the tip) were determined. RESULTS:Increasing vacuum increased efficiency only when going from 200 mm Hg to higher vacuum levels. Increasing aspiration increased efficiency at all points measured (25 mL/min versus 35 mL/min, P < .0001; 35 mL/min versus 50 mL/min, P = .012; 25 mL/min versus 50 mL/min, P < .0001). Chatter was highest at 200 mm Hg and decreased when vacuum was increased from 200 mm Hg to 300 mm Hg and up. Chatter decreased with increasing flow. CONCLUSIONS:Vacuum improved efficiency only up to 300 mm Hg and was more dependent on increasing flow. Similarly, chatter correlated with 200 mm Hg vacuum only and was more correlated with flow. Limitations of this study include use of only 1 US power modulation and hard nuclear material. FINANCIAL DISCLOSURE:No author has a financial or proprietary interest in any material or method mentioned.

PURPOSE: To determine the optimum power settings in micropulsed ultrasound (US).SETTING: John A. Moran Eye Center Laboratories, University of Utah, Salt Lake City, Utah, USA.DESIGN: Experimental study.METHODS: Pig lenses hardened to be comparable to dense human cataracts were cut into 2.0 mm cubes and removed using micropulsed longitudinal US with previously optimized settings (6 milliseconds on and 6 milliseconds off and using a 0.9 mm 30-degree beveled bent phaco tip). The aspiration was set at 40 mL/min and the vacuum level at 550 mm Hg. Twenty lens cubes were tested with the power set from 10% to 100% in increments of 10%. Primary outcome measures were efficiency time (time to lens removal) and chatter (number of times the lens fragment visibly bounced off the tip).RESULTS: Efficiency time decreased with increasing power. There was a correlation between power and efficiency time (R-2 = 0.41, P =.046), which was more substantial between 30% and 100% power (R-2 = 0.71, P =.004). The mean number of chatter events did not differ significantly between power settings (R-2 = 0.012, P =.1195).CONCLUSIONS: There was a 5-fold increase in efficiency between 10% power and 20% power, which likely indicates that there is a minimum power threshold for efficient breakup of the lens. Between 20% and 100% power, there was a linear, strong, and statistically significant improvement in efficiency in these lens fragments. In addition, with micropulsed US there was little chatter or microchatter throughout the power range. (C) 2015 ASCRS and ESCRS

Objective: The aim of this study was to evaluate bent and straight phacoemulsification tips to determine which tip is more efficient in removal of lens fragments, using micropulsed longitudinal ultrasound in phacoemulsification.Design: In vitro laboratory study.Methods: The John A. Moran Eye Center Laboratories, University of Utah, Salt Lake City, Utah, was the study setting. Pig lenses hardened in a manner comparable with dense human cataracts were cut into 2-mm cubes and removed with micropulsed longitudinal ultrasound using settings previously shown to be optimally efficient (6 milliseconds on and 6 milliseconds off for a bent tip). To verify this time as most efficient for a straight tip, we also tested times of 5, 6, and 7 milliseconds time on and off. The tips were either straight or with a 20-degree bend. Twenty cubes were used for each comparative run.Results: For the straight tip, 6 milliseconds on (1.56 +/- 0.815 seconds) was significantly more efficient than 7 milliseconds on (2.45 +/- 1.56 seconds, p = 0.001) and not significantly more efficient than 5 milliseconds on (1.69 +/- 0.86 seconds, p = 0.43). Five milliseconds off time (1.45 +/- 0.76s) was more efficient than 6 milliseconds (2.06 +/- 1.37 seconds, p = 0.004) and 7 milliseconds off (2.18 +/- 1.24s, p = 0.001). The straight tip was more efficient than the bent tip (1.38 +/- 0.83 versus 2.93 +/- 2.14 seconds, p = 0.006).Conclusions: Results are contrary to accepted common belief. Micropulsed longitudinal phacoemulsification is more efficient with a straight rather than a bent tip.

PURPOSE:To evaluate pulse type technology used to remove lens fragments during phacoemulsification.SETTING:John A. Moran Eye Center Laboratories, University of Utah, Salt Lake City, Utah, USA.DESIGN:Experimental study.METHODS:Lens nuclei soaked in 10 mL of 10% neutral buffered formalin for 2 hours were placed in 10 mL of balanced salt solution. Lenses were cut into 2 mm × 2 mm cubes; no more than 36 hours later, cubes were randomly selected for testing. Two aspiration and 2 vacuum settings were assessed at moderate- and high-flow and vacuum (30 mL/min and 300 mm/Hg, low-flow vacuum; 50 mL/min and 500 mm/Hg, high-flow vacuum), with continuous 50 milliseconds on and off (long pulse) and 6 milliseconds on and off (micropulse) ultrasound.RESULTS:There was a significant difference in efficiency favoring micropulse compared with combined long pulse and continuous pulse in high-flow vacuum at 80% power (P = .018) and between combined long pulse and continuous pulse versus micropulse in high-flow vacuum at 20% power (P = .019). Low-flow vacuum micropulse was more efficient than continuous (19.7%) (P < .0001) and long pulse (22.7%) (P < .0001). Continuous and long pulses were not significantly different from one other. There was a significant difference in chatter rates between high-flow vacuum and low-flow vacuum when all results were compared (P < .0001), with no additional significant differences found.CONCLUSION:Micropulse technology was better than continuous and long pulse at moderate but not high-flow and vacuum settings. At the higher setting, chatter was observed less often, with all modalities more efficient than the lower setting.

PURPOSE: To evaluate the optimum off time for the most efficient removal of lens fragments using micropulse ultrasound (US).SETTING: John A. Moran Eye Center Laboratories, University of Utah, Salt Lake City, Utah, USA.DESIGN: Experimental study.METHODS: Porcine lens nuclei were soaked in formalin for 2 hours and then cut into 2.0 mm cubes using the Signature US machine with a bent 0.9 mm phaco tip with a 30-degree bevel. The on time was 7 milliseconds (ms), and the off time was varied from 2 to 20 ms in 2 ms steps. Phacoemulsification efficiency (time for fragment removal) and chatter (number of times the fragment bounced from the tip) were measured.RESULTS: A nonsignificant linear increase in efficiency was observed with 2 to 6 ms of off time (R-2 = .87, P = .24). A significant linear decrease in efficiency was observed with 6 to 20 ms (R-2 = .74, P = .006).CONCLUSIONS: With micropulse longitudinal US, 6 to 7 ms of off time was as efficient as shorter off times; longer off times (8 to 20 ms) showed decreased efficiency. Chatter was minimal and statistically similar throughout. To maximize phacoemulsification US efficiency, an off-time setting of 6 ms is recommended.

The eye is an attractive organ for non-invasive discovery and monitoring of disease progression. Traditionally, fluorescein angiography (FA) and indocyanine green angiography (ICGA) have been used for dynamic evaluation of the retina and its vasculature. However, both fluorescein and indocyanine green (ICG) possess considerable disadvantages. FA is limited to assessing superficial retinal blood flow and often results in an unclear view due to fluorescein leakage. This obscures important pathologies such as neovascularization, ischemia and inflammation. ICG, a near-infrared fluorophore (NIRF), has nonspecific binding, high uptake and retention in tissues, as well as detrimental effects on the hepatobiliary tract. Here, we present a potential contrast agent for imaging ocular vascular permeability with ZW800, a heptamethine indocyanine NIRF, conjugated to polystyrene latex beads (ZW800m). ZW800 is an excellent alternative for near-infrared imaging, as it has excellent contrast, superior clearance, and is amendable to conjugation. ZW800m conjugation is an easy, attractive method of in vivo imaging and real-time tracking of ocular vascular pathologies. ZW800m is readily imaged via commercially available laser ophthalmoscope (SLO, HRA OCT, Spectralis) to assess vascular permeability in the mouse retina and choroid. In Type 1 diabetic Ins2Akita mice, ZW800m was observed in mouse retina but not in wild-type mice. After laser-induced choroidal neovascularization (CNV), ZW800m was observed in mouse choroid but not in control. In both CNV and diabetic mice, ZW800 imaging showed increased hyperfluorescence on ICG modality (ICGA) not seen on FA. Presence of ZW800m in respective tissues was confirmed ex vivo with flatmounts visualized with EVOS 800 nm light cube. ZW800 imaging may be easily employed in the research laboratory.

PURPOSE: To determine the optimal longitudinal power settings for Infiniti OZil Intelligent Phaco (IP) at varying torsional amplitude settings; and to test the hypothesis that increasing longitudinal power is more important at lower torsional amplitudes to achieve efficient phacoemulsification.DESIGN: Laboratory investigation.METHODS: SETTING: John A. Moran Eye Center, University of Utah, Salt Lake City, Utah. PROCEDURE: Individual porcine nuclei were fixed in formalin, then cut into 2.0 mm cubes. Lens cube phacoemulsification was done using OZil IP at 60%, 80%, and 100% torsional amplitude with 0%, 10%, 20%, 30%, 50%, 75%, or 100% longitudinal power. All experiments were done using a 20 gauge 0.9 mm bent reverse bevel phaco tip at constant vacuum (550 mm Hg), aspiration rate (40 mL/min), and bottle height (50 cm). MAIN OUTCOME MEASURE: Complete lens particle phacoemulsification (efficiency).RESULTS: Linear regression analysis showed a significant increase in efficiency with increasing longitudinal power at 60% torsional amplitude (R-2 = 0.7269,P = .01) and 80% torsional amplitude (R-2 = 0.6995, P = .02) but not at 100% amplitude (R-2 = 0.3053, P = .2). Baseline comparison of 60% or 80% vs 100% torsional amplitude without longitudinal power showed increased efficiency at 100% (P = .0004). Increasing longitudinal power to 20% abolished the efficiency difference between 80% vs 100% amplitudes. In contrast, 75% longitudinal power abolished the efficiency difference between 60% vs 100% torsional amplitudes.CONCLUSIONS: Results suggest that longitudinal power becomes more critical at increasing phacoemulsification efficiencies at torsional amplitudes less than 100%. Increasing longitudinal power does not further increase efficiency at maximal torsional amplitudes. (C) 2014 by Elsevier Inc. All rights reserved.

PURPOSE. Wound induced corneal fibrosis can lead to permanent visual impairment. Keratocyte activation and differentiation play a key role in fibrosis, and vimentin, a major structural type III intermediate filament, is a required component of this process. The purpose of our study was to develop a nonviral therapeutic strategy for treating corneal fibrosis in which we targeted the knockdown of vimentin.METHODS. To determine the duration of plasmid expression in corneal keratocytes, we injected a naked plasmid expressing green fluorescent protein (GFP; pCMV-GFP) into an unwounded mouse corneal stroma. We then injected pCMV-GFP or plasmids expressing small hairpin RNA in the corneal wound injury model (full-thickness corneal incision) to evaluate opacification.RESULTS. GFP expression peaked between days 1 and 3 and had prominent expression for 15 days. In the corneal wound injury model, we found that the GFP-positive cells demonstrated extensive dendritic-like processes that extended to adjacent cells, whereas the vimentin knockdown model showed significantly reduced corneal opacity.CONCLUSIONS. These findings suggest that a nonviral gene therapeutic approach has potential for treating corneal fibrosis and ultimately reducing scarring.

Angiogenesis plays a key role in tumor growth. Vascular endothelial growth factor (VEGF) is a pro-angiogenic that is involved in tumor angiogenesis. When VEGF binds to membrane-bound vascular endothelial growth factor receptor 2 (mVEGFR2), it promotes angiogenesis. Through alternative polyadenylation, VEGFR2 is also expressed in a soluble form (sVEGFR2). sVEGFR2 sequesters VEGF and is therefore anti-angiogenic. The aim of this study was to show that treatment with a previously developed and reported antisense morpholino oligomer that shifts expression from mVEGFR2 to sVEGFR2 would lead to reduced tumor vascularization and growth in a murine colon cancer xenograft model. Xenografts were generated by implanting human HCT-116 colon cancer cells into the flanks of NMRI nu/nu mice. Treatment with the therapeutic morpholino reduced both tumor growth and tumor vascularization. Because the HCT-116 cells used for the experiments did not express VEGFR2 and because the treatment morpholino targeted mouse rather than human VEGFR2, it is likely that treatment morpholino was acting on the mouse endothelial cells rather than directly on the tumor cells.

Background: We report 2 patients who have undergone radial keratotomy (RK) preceding ReSTOR® multifocal intraocular lens (IOL; Alcon, Fort Worth, Tex., USA) implantation in their nondominant eyes and TECNIS® monofocal IOL (Abbott Medical Optics, Abbott Park, Ill., USA) in their dominant eyes. Methods: Retrospective review of 2 patients who underwent hybrid monovision with ReSTOR® multifocal and TECHNIS® monofocal IOLs at the time of cataract surgery after a remote history of RK. Results: Implantation of the ReSTOR® multifocal and the TECHNIS® monofocal IOLs was successful, with no reported adverse events. The patients were able to achieve spectacle freedom. Conclusion: We report a novel technique for the management of post-RK patients to optimize their chances for spectacle independence.

PURPOSE: To evaluate radiused and nonradiused phacoemulsification tips to determine which tip is more efficient in removal of lens fragments using 3 ultrasound (US) modalities.SETTING: John A. Moran Eye Center Laboratories, University of Utah, Salt Lake City, Utah, USA.DESIGN: Experimental study.METHODS: Porcine lens nuclei were formalin-soaked for 2 hours or 3 hours and then divided into 2.0 mm cubes. Thirty-degree, 0.9 mm beveled radiused tips and nonradiused tips were used with torsional, transverse, and micropulsed US modalities. Bent tips were used with torsional and transversal US, and straight tips were used with micropulsed US. Efficiency (time to lens removal) and chatter (number of lens fragment repulsions from the tip) were determined.RESULTS: The mean phacoemulsification efficiency was statistically significantly decreased (increased time for removal) with the radiused tip compared with the nonradiused tip for torsional US only (2-hour soaked lenses: 2.14 seconds +/- 1.94 [SD] versus 1.18 +/- 0.69 seconds [P<.05]; 3-hour soaked lenses: 5.07 +/- 4.2 seconds versus 2.52 +/- 1.99 seconds [P<.05]). There was no difference in chatter results.CONCLUSION: The radiused tip showed decreased efficiency with torsional US only. (C) 2014 ASCRS and ESCRS

Background: We report the case of a 40-year-old female patient treated with implantation of the Acrysof® IQ ReSTOR® lens (Alcon, Fort Worth, Tex., USA) with overlaying Acrysof EXpand® minus piggyback lens (Alcon). Methods: The patient had high myopia and was diagnosed with presbyopia and bilateral posterior subcapsular cataract. She desired to be spectacle-free and opted to undergo bilateral placement of the ReSTOR multifocal lens. The necessary intraocular lens (IOL) power was +3.5 in the right eye and +4.0 in the left eye, though the range of commercially available ReSTOR lenses is +6.0 to +34.0 D. In order to achieve emmetropia in this case of high myopia, it was determined that an EXpand minus piggyback lens would be necessary. Results: Implantation of the ReSTOR lens with overlaying EXpand minus piggyback lens was performed successfully and without complication. At 5 months postoperatively, the patient had 20/20 uncorrected visual acuity in both eyes. She reported a high level of satisfaction and was able to return to her daily activities including reading and driving without spectacles. Conclusion: We report successful primary implantation of AcrySof EXpand minus piggyback lenses overlying the AcrySof IQ ReSTOR lens in a patient with high myopia. Long-term follow-up and further evaluation is necessary to establish piggyback IOL implantation with multifocal IOL as an accepted treatment for high myopia with presbyopia.