Balanced Tip Research Articles

Discrepancies in CDE and Measured Phaco Tip Energy: Comparison of Energy Produced in Longitudinal and Torsional Ultrasound Using Calorimetry.

This study aims to investigate the differences between the heat energy produced during cataract surgery and Cumulative dissipated energy (CDE). CDE is often used as a medium for understanding the energy delivered to the eye during cataract surgery. However, the actual energy produced at the tip level of the tip is not well understood. We propose that a discrepancy may exist between the CDE reported by the surgical machine and the actual energy delivered to the eye. About 50 mL of distilled water were degassed and placed in an isobaric calorimeter. Using the Alcon Centurion and Ozil handpiece fitted with the balanced tip, an investigator immersed the phaco tip into the water and pressed the foot pedal to position 3. The device was set to 100% continuous power, vacuum to 0mmHg, with aspiration 12 mL/min aspiration. To prevent system changes in the system within the calorimeter, the aspiration tubing was occluded. Temperature change recorded by another investigator was observed from 0 to 60seconds. After 60seconds the first researcher immediately released the pedal and removed the phaco tip from the water. Trials were performed 10 times using solely torsional or longitudinal settings and averaged. CDE also was recorded and averaged. No significant difference was seen in the temperature change or energy calculated in Joules between ultrasound modalities, with torsional producing a magnitude of 163 J and longitudinal producing 172 J (P = 0.2). However, the CDE generated in the 60seconds period was significantly different, with a magnitude of 61 for longitudinal compared to 24 for torsional (P < 0.001). Significantly more energy was generated using torsional ultrasound than longitudinal at the tip level of the tip. CDE did not appear to accurately reflect these differences. This suggests that other factors should be considered when evaluating CDE and surgical outcomes.

In vitro analysis of clinically relevant aspects of a polymer-coated phacoemulsification tip vs a traditional tip.

To compare the in vitro incisional temperature, acoustic energy, transient cavitation, and turbulence of the polymer-coated hybrid phacoemulsification tip with the balanced tip. Pasteur Ophthalmology Clinic, Vitacura, Santiago, Chile. Laboratory study. The Centurion Vision System with Active Sentry handpiece was used with tips operated in torsional mode, and stroke was normalized. For thermal measurements, controlled loads were applied over the tip sleeve simulating the pressure applied at the expected level of the corneal incision. Heat generated was recorded on a blackbody filmstrip using infrared imaging. A directional hydrophone provided 360° mapping of acoustic pressure. Cavitation patterns with increasing ultrasound power were imaged with high-speed video recording. Particle image velocimetry was used to evaluate turbulence, streaming, and bubble formation. The temperature rise for the hybrid and balanced tips was lower than with the control mini-flared Kelman tip ( P ≤ .0001). The hybrid tip generated reduced acoustic output compared with the balanced tip. Ultrasound threshold for cavitation was higher for the hybrid vs balanced tip (55% vs 25%). Fluid turbulence was more evident with the balanced tip compared with the hybrid tip at all flow conditions when normalized for stroke at 60% and 80% power for balanced and hybrid tip, respectively. The polymer-coated hybrid tip showed reduced heat generation compared with the control mini-flared Kelman tip and had lower acoustic output, lower cavitation, and lower turbulence compared with the balanced tip, suggesting potential for improved clinical safety.

Efficiency of a polymer-coated phacoemulsification tip in cataract surgery.

To determine whether there is a difference in efficiency during phacoemulsification when using the hybrid polymer tip compared with the metal balanced tip, as measured by cumulative dissipated energy (CDE) and total procedure time. John A. Moran Eye Center, University of Utah, Salt Lake City, Utah. Experimental study. Phacoemulsification was performed with the Centurion Vision System and Infiniti OZil handpiece, with a 30-degree bevel metal balanced tip and hybrid polymer tip. The vacuum was set at 500 mm Hg and the aspiration flow rate at 50 mL/min. Power was changed for torsional and longitudinal ultrasound (US) at 20%, 40%, 60%, 80%, and 100%. Hardened porcine lenses were cut into 200 two mm cubes, 10 for each specified tip/power setting. They were placed into an artificial anterior chamber filled with a balanced salt solution, and phacoemulsification was performed. A second observer randomly assigned the US type and power. The same observer timed trials with a stopwatch, and CDE was recorded. There were no significant differences in time or CDE for any power levels or US modes when comparing the 2 tips. No significant difference in efficiency was observed when comparing the metal balanced tip with the hybrid polymer tip. Given the known improved safety profile and the overall equivalent efficiency of the hybrid tip, it could improve the performance of beginning and advanced surgeons in the future. Future study is needed to evaluate other setting combinations and to evaluate the hybrid tip in clinical settings.

Torsional Power and Tip Shape Greatly Change Irrigation Flow Feeding Rate.

It is important to maintain intraocular pressure during cataract surgery. When the intraocular pressure sharply drops during phacoemulsification, it is important to ensure a compensatory maximum fluid supply. To the best of our knowledge, this is the first study presenting the maximum irrigation flow supply using an ultrasonic tip shape and torsional power setting. The weight of BSS PLUS 500 ejected during torsional oscillation fitted with a mini-tip or balanced tip and nano sleeve with IOP set at 20 mmHg (IOP20) or 40 mmHg (IOP40) was measured. The weight of the BSS ejected from the sleeve over 3.0 s (15 measurements taken at 200-ms intervals) was measured to calculate the irrigation flow feeding rate. Measurements were made four times at each torsional power setting (TP). With a balanced tip, the irrigation flow rate rose as TP was increased, whereas, at 60% or 90% TP, the irrigation flow rate markedly decreased. With the mini-tip, the irrigation flow rate remained relatively stable, up to 60% or 80% TPbut decreased dramatically at higher power settings. Compared with IOP20, the irrigation flow rate increased by 1.21- to 1.28-fold with the balanced tip and by 1.28- to 1.41-fold with the mini-tip at IOP40. At IOP20, the irrigation flow rate was higher with the mini-tip at 0% and 5% TP but equal to or higher with the balanced tip at TP of ≥10%. At IOP40, the irrigation flow rate with the mini-tip was equal to or higher than that with the balanced tip at all TP. The irrigation flow rate tends to vary with changes in TP and tip shape.

Corneal endothelium protection provided by ophthalmic viscosurgical devices during phacoemulsification: experimental study in rabbit eyes.

To compare the protection of the corneal endothelium provided by a cohesive and a dispersive ophthalmic viscosurgical device (OVD) against damage from torsional ultrasound and simulated lenticular debris during phacoemulsification. University setting, Salt Lake City, Utah. Experimental study. 15 New Zealand rabbits were included. After incision, each eye received cohesive or dispersive OVD (ProVisc or Viscoat). 10 1.0 mm beads were injected to simulate lenticular debris. The Intrepid Balanced tip (Centurion Ozil handpiece) was inserted into the anterior chamber, and 60% torsional ultrasound with 50 mL/min flow, 70 mm Hg intraocular pressure, and 600 mm Hg vacuum was applied (20 seconds). Cumulative dissipated energy (CDE) was noted. After euthanasia and enucleation, corneas were removed, stained with trypan blue/alizarin red, and photographed (5 ×400 magnification photos and 1 overview photograph from each cornea). ImageJ was used to evaluate cell damage and loss. CDE was 4.70 ± 0.26 and 4.64 ± 0.10 in the cohesive and dispersive OVD groups, respectively ( P = .8647). The analysis of the ×400 photographs showed that the percentage of intact cells was statistically higher in the dispersive OVD group ( P = .0002), whereas the percentages of damaged and lost cells were statistically higher in the cohesive OVD group ( P = .0002 and .0059, respectively). Overview photographs revealed the presence of residual OVD on the endothelium, especially in the dispersive group. In this experimental study using a rabbit model, the corneal endothelium protection provided by the dispersive OVD was superior to that provided by the cohesive OVD.

Effect of simulated lenticular debris on corneal endothelial cells: experimental study in rabbit eyes.

To evaluate mechanical damage of simulated lenticular debris on corneal endothelial cells during phacoemulsification. University setting, Salt Lake City, Utah. Experimental study. 12 New Zealand rabbits underwent bilateral surgery. After incision, 10 1.0 mm beads were injected into the anterior chamber of test eyes to simulate lenticular debris. A balanced salt solution was injected into the contralateral eyes with the same injector. The Intrepid Balanced Tip of the Centurion Ozil handpiece was inserted into the anterior chamber, and 60% torsional ultrasound was applied for 20 seconds with 50 mL/min flow, 70 mm Hg intraocular pressure, and 600 mm Hg vacuum. Cumulative dissipated energy (CDE) was noted. After euthanasia and enucleation, the corneas were removed, stained with trypan blue/alizarin red, and photographed in a standardized manner (×400 photographs from 5 specific areas and 1 overview photograph from each corneal button). The ImageJ program was used to evaluate cell damage and loss in the photographs. CDE was 4.64 ± 0.19 for test eyes with beads and 4.66 ± 0.17 for control eyes without beads ( P = .58). The percentage of intact cells was statistically higher in the control group ( P = .0005), whereas the percentages of damaged and lost cells were statistically higher in the test group ( P = .0010 and .0005, respectively). This was observed in the analysis of the ×400 photographs and overview photographs. This study suggests that lenticular debris swirling around the anterior chamber may cause significant damage to the corneal endothelium, providing further insight on mechanisms of damage during phacoemulsification.

Comparisons of the energy efficiency and intraocular safety of two torsional phacoemulsification tips

BackgroundDuring cataract phacoemulsification surgery, an Intrepid® balanced (IB) tip can achieve a larger amplitude, which may lead to higher energy efficiency than a Kelman (K) tip when paired with a torsional phaco platform. In this retrospective cohort study, we compared their energy efficiency and damage to the cornea under a new energy setting.MethodsThe medical records of 104 eyes of 79 patients were reviewed, with 47 eyes belonging to the IB group and 57 eyes belonging to the K group. All surgeries were performed on an Alcon Centurion® platform with gravity infiltration. Surgical parameters, visual outcome, central corneal thickness (CCT) changes, and endothelial cell density (ECD) loss rate were recorded and calculated.ResultsNo significant differences in postoperative best corrected visual acuity (BCVA), intraocular pressure (IOP), total ultrasound time, estimated fluid aspirated, CCT changes, or ECD loss rate were observed between the two groups. We divided the included eyes into soft nucleus and hard nucleus subgroups and found lower cumulative dissipated energy (CDE, 8.15 ± 8.02 vs 14.82 ± 14.16, P = 0.023), cumulative torsional energy (CTE, 8.06 ± 7.87 vs 14.13 ± 13.02, P = 0.027), and cumulative longitudinal energy (CLE, 0.09 ± 0.17 vs 0.69 ± 1.37, P = 0.017) in the IB group than in the K group, implying less energy used and higher energy efficiency of the IB tip.ConclusionLower CLE in the IB group indicates fewer phaco tip obstructions and a significantly higher capability to conquer hard nuclei with IB tips with statistical significance. With an ultra-perfusion cannula, the balanced tip does not cause more corneal damage.

Comparing surgical efficiencies between phacoemulsification systems: a single surgeon retrospective study of 2000 eyes.

To compare under similar conditions intraoperative surgical efficiencies metrics between an active fluidics and a gravity based phacoemulsification systems. Adult patients who were diagnosed with a cataract that compromised visual acuity inferior to 20/40 were included in the study. Patients were excluded from the study if they had a history of severe retinal disorders, clinically significant corneal endothelial dystrophy or history of corneal disease. All phacoemulsification surgeries were performed by a single surgeon. Both phacoemulsification systems used the 0.9 mm 45-degree aspiration bypass system Intrepid Balanced tip and the 0.9 mm Intrepid Ultra infusion sleeve. All cataracts were classified using the Lens Opacities Classification System III, cumulative dissipated energy (CDE) and aspiration fluids were measured in each surgery. Totally 2000 eyes were included in the study. Phacoemulsification was performed in 1000 (50%) eyes with an active fluid dynamics system and in 1000 (50%) eyes with a gravity-based fluidic system. Mean CDE until fracture of the lens was 1.1 and 1.9 percent-seconds and total mean CDE used was 5.6 and 7.2 percent-seconds using an active fluidics dynamics system and gravity-based fluidic system, respectively (P<0.001). Mean aspiration fluids used were 70 mL using an active fluidics dynamics system and 85 mL using a gravity-based fluidic system (P<0.001). This study evidences that surgeries performed under similar conditions (same surgeon, phaco tip and sleeve) with the active fluidics dynamics system required significantly lower CDE and aspiration fluids.

Effect of phacoemulsification fluid flow on the corneal endothelium: experimental study in rabbit eyes.

To quantify the damage to the corneal endothelium from the flow of a balanced salt solution during phacoemulsification. John A. Moran Eye Center, University of Utah, Salt Lake City, Utah. Experimental study. 12 New Zealand white rabbits received bilateral surgery. 6 eyes served as controls with no irrigation (incision only). In 18 eyes, the Intrepid Balanced tip of the Centurion Ozil (Alcon Laboratories, Inc.) handpiece was inserted into the anterior chamber for continuous irrigation at 50 mL/min with either 250 or 500 mL of balanced salt solution. After killing humanely and enucleation, the corneas were removed, stained with trypan blue-alizarin red, and photographed in a standardized manner (×400 photographs from 5 specific areas and 1 overview photograph from each corneal button). The ImageJ program was used to evaluate cell damage and loss in the photographs obtained from each cornea. Analysis of the ×400 photographs showed no statistically significant differences between control, 250 mL, and 500 mL groups in the percentage of intact, damaged, or lost cells (P = .896, .851, and .972 respectively). For the overview photographs, the differences in areas of intact and damaged cells among the groups were statistically significant, likely because of the peripheral areas of damage related to touches between the phacoemulsification tip and the endothelium during irrigation. The volume of balanced salt solution flow alone did not seem to be a major contributing source of endothelial cell damage and loss, providing further insight into mechanisms of corneal endothelium damage during phacoemulsification.

Effect of longitudinal and torsional ultrasound on corneal endothelial cells: experimental study in rabbit eyes.

To compare corneal endothelial damage from longitudinal and torsional ultrasound during phacoemulsification. John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Experimental study. 9 New Zealand white rabbits underwent bilateral surgery. After incision, the Intrepid Balanced Tip of the Centurion Ozil handpiece was inserted into the anterior chamber, and the following settings were used: 50 mL/min flow, 70 mm Hg intraocular pressure, 600 mm Hg vacuum, and 60% longitudinal (1 eye) or torsional (contralateral eye) ultrasound for 30 seconds. Cumulative dissipated energy (CDE) was noted. After euthanasia and enucleation, the corneas were removed, stained with trypan blue/alizarin red, and photographed (400× photographs from 5 specific areas and 1 overview photograph from each corneal button). The ImageJ program was used to evaluate cell damage and loss in the photographs obtained from each cornea. Cavitation bubbles around the phacoemulsification tip were generally observed in the longitudinal group. CDE was 17.4 ± 0.58 and 6.93 ± 0.15 in the longitudinal and torsional groups, respectively (P = .003). The percentage of intact cells was statistically higher in the torsional group (94.22% ± 5.99% vs 56.85% ± 22.29%), and the percentage of lost cells was statistically higher in the longitudinal group (42.10% ± 22.02% vs 4.97% ± 6.23%) (P = .003). This was observed in the analysis of the 400× photographs and the overview photographs. This study suggests that torsional ultrasound was associated with significantly less corneal endothelial cell damage than classical longitudinal tip motion, providing further insight on mechanisms of corneal endothelial damage during phacoemulsification.

The efficacy and safety profile of cataract procedures performed with a sensor-embedded handpiece and a new hybrid phaco tip.

To evaluate the efficacy and safety of the new Intrepid Hybrid tip and Active Sentry handpiece in comparison to the Intrepid Balanced tip and Centurion Ozil handpiece. One hundred sixty-eight eyes were included in the study and randomized into Group 1 (Active Sentry handpiece + Intrepid Hybrid tip, n = 86) and Group 2 (Centurion Ozil handpiece + Intrepid Balanced tip, n = 82). Data were collected from the phaco device, including total U/S time, cumulative dissipated energy (CDE), the total number of active surge mitigation actuations (ASM actuations), torsional amplitude, torsional amplitude on time, estimated fluid of aspirated, and aspiration time. Endothelial cell count (ECC) and central corneal thickness (CCT) were assessed. A correlation analysis was performed between ASM actuations, phaco metrics, and patient characteristics in Group 1. The CDE, torsional amplitude measured in Group 1 (8.8 ± 3.9, 51.2 ± 13.3, respectively) were significantly lower than those of Group 2 (10.4 ± 4.2, 65.2 ± 9.3, respectively). While no complications were observed in group 1, there were posterior capsule rupture in 2 eyes and iris damage in 1 eye in group 2. The mean ECC and CCT were similar at 1 month. The ASM actuations were more engaged in the eyes with pseudoexfoliation and small pupils. The combination of the new Intrepid Hybrid tip and Active Sentry handpiece enables safer cataract procedures without compromising efficacy due to its surge prevention mechanisms and special tip design. It could be a good option for residents in training.

Efficacy of Balanced Torsional Phacoemulsification Tip for Cataract Surgery.

Purpose:To compare the efficacy of the Intrepid® Balanced torsional phacoemulsification tip to that of the 30° Ozil® and 45° Kelman® tips using Centurion Vision System.Methods:This study included 150 eyes that underwent torsional phacoemulsification surgery using 30° Ozil® tip (Group 1, 48 eyes), Intrepid® Balanced tip (Group 2, 52 eyes), or 45° Kelman® tip (Group 3, 50 eyes). Ultrasound time (UST), cumulative dissipated energy (CDE), average phaco power, average torsional amplitude, balanced salt solution volume, aspiration and operation time, and preoperative, postoperative corrected distance visual acuity, central corneal thickness were recorded.Results:The mean UST, CDE, average phaco power, average torsional amplitude were 49.9 ± 15.7 s, 10.8 ± 4.5%-s, 23.9 ± 4.6%, and 51.4 ± 5.7% in the Ozil® group and 47.5 ± 10.6 s, 5.3 ± 2.2%-s, 12.5 ± 5.3%, and 28.9 ± 7.2% in the Intrepid® Balanced group, and 48.1 ± 12.7 s, 6.9 ± 3.3%-s, 18.9 ± 5.9%, and 39.2 ± 7.9% in the Kelman® group, respectively. The CDE, average phaco power, and average torsional amplitude of the Intrepid® Balanced group were significantly lower than other groups (P < 0.05). There was no statistically significant difference between the three groups in terms of UST and operation time (P > 0.05).Conclusion:Intrepid® Balanced tip, by means of its distinctive “double bent” design and balanced energy distribution, offers more effective phacoemulsification compared to conventional 30° Ozil® and 45° Kelman® tips.

Comparison of semicircular and bent tips regarding regional differences in oscillation amplitude under various torsional power settings.

To analyze the difference between the behavior of semicircular (balanced) and bent (mini) tips at 20 incremental torsional power settings. Tsukazaki Hospital, Himeji, Japan. Experimental study. Using an ultra-high-speed video camera HPV-X2, the 2 tips during torsional oscillation were recorded, comparing tip behavior at power settings from 5% to 100% by tracking points 1 to 5 (tip end and at 1325, 2650, 3975, and 5035 μm from the tip end). Both tips increased their amplitude widths, drawing an S-curve at all points as the torsional power setting was increased, reaching their upper limits from 70% to 90% torsional power. At all 20 power settings, both tips showed significantly different amplitudes (all P < .01), and the difference of the amplitude increased as the power setting increased. Although, at points 1 and 3, the balanced tip amplitude was nearly 1.5 times larger than the mini tip amplitude, the amplitude difference was 10 μm or less at points 2 and 4. At point 5, the mini tip amplitude was at least 3 times more than the balanced tip amplitude. The amplitude does not increase proportionally and varies markedly with the tip shape on reaching the upper limit, suggesting that a higher power setting might not contribute greatly to nuclear fragmentation. The balanced tip might cause greater damage to surrounding tissues if it is inserted at approximately 3 mm from the wound site. To obtain maximum shaft stability using the balanced tip, it is important to insert at least 5 mm.

Impact of torsional micropulse on phacoemulsification efficiency and chatter

ObjectiveEvaluate the effect of increasing ultrasound (US) power on chatter events and efficiency under both continuous and micropulse torsional US to reduce total cataract extraction times. DesignIn vitro laboratory study. MethodsPorcine lens nuclei were incubated in formalin for 2 hours and then cut into 2-mm cubes. Phacoemulsification was performed using the Centurion Vision System and Infiniti OZil handpiece with the balanced tip. Both US modalities were studied at 60%, 80%, and 100% power. Micropulse rate was 83 pulses per second with 50% on time. Each combination comprised 20 runs. Efficiency was considered as the total time for a cube to be emulsified; chatter was the number of times the lens fragment bounced off the tip. ResultsThere was significant decrease in efficiency when power was increased from 60% to 100% (1.33–1.97 s; p < 0.001) under micropulse US and significant increase in chatter when power was further increased to 100% from 60% (0.15–0.94 s; p < 0.001). There was no significant efficiency change with increased power under continuous US. Comparing the phacoemulsification efficiency between continuous and micropulse US, we found no significant difference at 60% and 80% power; at 100% power, continuous was significantly more efficient than micropulse (1.48 and 1.97 s, respectively; p = 0.001). ConclusionsIncreasing power above 60% decreased efficiency under torsional micropulse US. We believe that this was due to the chatter increase observed with increasing US power. Torsional continuous US was significantly more efficient than micropulse US at 100% power.

Determining optimal ultrasound percent on time with long-pulse torsional phacoemulsification

ObjectiveTo evaluate the optimum percent on time for the most efficient lens fragment removal using long-pulse torsional ultrasound (US). DesignIn vitro laboratory study. MethodsPorcine lens nuclei were incubated in formalin for 2 hours and then cut into 2 mm cubes. Phacoemulsification was performed using the Centurion® Vision System and Infiniti OZil handpiece with the balanced tip. Vacuum was set at 500 mm Hg, aspiration rate at 50 mL/min, and intraocular pressure (IOP) at 50 mm Hg. Pulse rate was 26 pulses/second. Studied parameters were percent power: 60%, 80%, and 100%, and percent on times: 50%, 60%, 70%, and 80%. Efficiency was the total time for a cube to be emulsified. Chatter was the number of times the lens fragment bounced off the tip. ResultsThere was no significant difference in efficiency between 50%, 60%, and 70 % on-time settings (p = 0.17 and 0.08, respectively); however, there was significant increase in efficiency when the on time was increased from 70% to 80% (p = 0.03). Increasing power from 60% to 100% showed a statistically significant efficiency increase (p = 0.001). There was no significant change in chatter with increasing on time; however, there was a statistically significant increase in chatter with every power level increase. ConclusionIncreasing on-time percent does not improve efficiency under torsional long-pulse US. There is no significant change in chatter with increasing on-time percent. Increasing power increases efficiency despite chatter increase. Long-pulse US does not appear to influence torsional action in a clinically meaningful way.

Effectivity and Safety of a Modified Tip Design in Torsional Phacoemulsification

Torsional mode phacoemulsification results in more effective fragmentation of the nucleus due to a different movement of the phacotip. In this clinical study, we investigated the influence of a modified tip design and active fluidics on the efficacy of phacoemulsification and safety for the corneal endothelium. We conducted a prospective randomized 2 : 1 study in which 40 patients were operated on with the mini-flared Kelman Tip using the Infiniti® System (group 1), and 20 patients were operated on with the Intrepid® Balanced Tip and the Centurion® System. We analyzed the intraoperative cumulative dissipated energy and also the density of the corneal endothelium measured with an endothelial microscope (CEM 530, Nidek) pre- and postoperatively. Both groups did not differ preoperatively in age, sex, axial length of the globe or corneal endothelium cell density nor cataract density (LOCS3). All surgeries were uneventful. The cumulative dissipated energy in group 1 (mini-flared Kelman tip, Infiniti System) was 38% higher than in group 2 (balanced tip, Centurion System; p < 0.05). The endothelial cell loss was 8% in group 1 and 10.3% in group 2 (p > 0.05). The cell size (polymegathism) increased in both groups significantly with + 37 µm in group 1 (p < 0.05) und + 54 µm in group 2 (p < 0.05). There was no statistically significant difference between both groups (p > 0.05). The number of hexagonal cells (pleomorphism) and corneal thickness did not differ in both groups either pre- nor postoperatively. Compared to torsional phacoemulsification with a mini-flared Kelman Tip and gravity fluidics, torsional phacoemulsification with a modified tip design and active fluidics is 38% more effective regarding the cumulative dissipated energy. Endothelial cell loss occurs to a similar extend using both systems. The postoperative changes in cell size (polymegathism), number of hexagonal cells (pleomorphism) and corneal thickness (pachymetry) were similar among both systems. We conclude, that the intraoperative stress on the endothelium is equivalent with both systems used.

Optimization and comparison of a 0.7 mm tip with the 0.9 mm tip on an active-fluidics phacoemulsification platform

To assess the effect of varying levels of torsional power on phacoemulsification efficiency using an active-fluidics phacoemulsification platform with a 0.7mm Sonata tip. John A. Moran Eye Center Laboratories, University of Utah, Salt Lake City, Utah, USA. Experimental study. A 0.7mm tip was used to emulsify 2.0mm porcine lenses that had been hardened in formalin. The torsional power was varied from 10% to 100% at intervals of 10%, and efficiency and chatter were recorded. A comparison of the 0.7mm tip with the 0.9mm Balanced tip was also performed. Using a torsional power setting of 90% and 100%, the 0.7mm tip and the 0.9mm tip efficiency times were recorded. The study showed an increase in efficiency as torsional power increased. The relationship was linear and more efficient up to 90% (R2=.8025, P=.0005). Chatter was only observed at a torsional power setting of 60%. In addition, a head-to-head comparison of the 0.7mm tip with the 0.9mm tip showed that both tips were statistically similar in efficiency times, despite the smaller diameter of the 0.7mm tip. The optimum torsional power setting with the Centurion platform in conjunction with the 0.7mm tip was 90%. The efficiency of the 0.7mm tip and the 0.9mm tip was statistically similar.

Effect of IOP based infusion system with and without balanced phaco tip on cumulative dissipated energy and estimated fluid usage in comparison to gravity fed infusion in torsional phacoemulsification

BackgroundTo evaluate the effect of three different combinations of tip designs and infusion systems in torsional phacoemulsification (INFINITI and CENTURION) in patients with cataract. According to the manufacturer, two unique improvements in the Centurion are: active fluid dynamic management system and use of an intrepid balanced tip. The study specifically aimed to evaluate the beneficial effects, if any, of change in tip design and infusion system individually and in combination on both per-operative parameters as well as endothelial health over 6 months.MethodsOne hundred and twenty six consenting patients of grade 4.0–6.9 senile cataract were randomized into three groups for phacoemulsification: Group A (n = 42): Gravity fed infusion system and 450 Kelman miniflared ABS phaco tip; Group B (n = 42): intraocular pressure (IOP) based infusion system and 450 Kelman miniflared ABS phaco tip; Group C (n = 42): IOP based infusion system and 450 Intrepid balanced phaco tip. The cumulative dissipated energy (CDE), estimated fluid usage (EFU) and total aspiration time (TAT) were compared peroperatively. The endothelial parameters were followed up postoperatively for six months.ResultsThe three arms were matched for age (p = 0.525), gender (p = 0.96) and grade of cataract (p = 0.177). Group C was associated with significant reductions in CDE (p = 0.001), EFU (p < 0.0005) as well as TAT (p = 0.001) in comparison to the other groups. All three groups had comparable baseline endothelial cell density (p = 0.876) and central corneal thickness (p = 0.561). On post-operative evaluation, although all groups were comparable till 3 months, by 6 months, the percentage losses in endothelial cell density were significantly lower in group C as compared to the other groups.ConclusionsUse of an IOP based phacoemulsification system in association with use of the Intrepid balanced tip reduces the CDE, EFU and TAT in comparison to a gravity fed system with a mini flared tip or IOP based system with a mini flared tip while also providing better endothelial preservation thus favouring the use of an IOP fed system with a balanced tip.Trial registrationTrial registration No.: CTRI/2016/06/007022.

Can we improve the efficacy of modern cataract surgery by using different tip designs? A comparison of balanced and tapered tip in femtosecond laser-assisted cataract surgery and manual phacoemulsification.

Different tip designs in modern cataract surgery have not been studied between the reported systems. Aim of this study is to assess the efficacy of two tip designs, Intrepid® balanced tip (BT) and Kelman tapered tip (TT), in femtosecond laser assisted cataract surgery (FLACS) and the microcoaxial torsional phacoemulsification. Prospective randomized unmasked cohort outcome study (hospital setting). Threehundert-forty-three eyes of 343 patientes underwent cataract surgery. Data of n=196 FLACS and n=147 manual phacoemulsification were analysed. Intrepid® balanced tip and Kelman tapered tip, Alcon, USA, were tested in FLACS (LenSx Alcon, USA) und manual phaco (Alcon Centurion System, USA). Four study cohorts were formed; FLACS BT (n=90, 70.2 years), FLACS TT (n=106, 68.1years), Manual BT (n=70, 71.3 years), Manual TT (n=77, 71.8 years). The nuclei were graded in Lens Opacities Classification System (LOCS) II,III and IV. Cumulative dissipated energy (CDE%s), balanced salt solution volume (BSSml), total longitudinal energy (%s) and torsional amplitude (%s). Lower CDE values were seen in FLACS compared to manual phacoemulsification (CDE %s median FLACS BT 3.28, FLACS TT 4.07, Manual BT 5.57, Manual TT 6.27). There was a significant difference between CDE FLACS BT and FLACS TT (p=0.038), and between FLACS BT and Manual TT (p=0.001). The right choice of tip designs in advanced phacoemulsification systems is a key factor in increasing efficacy in cataract surgery. The balanced tip showed a considerable energy-saving advantage in FLACS and manual phacoemulsification compared to the tapered tip.

Improvement of Phaco Tip Geometry During Torsional Phacoemulsification

Advanced cataract with hard lens nuclei frequently challenge the ophthalmologic surgeon when doing phacoemulsification. In the present study, we examined the effect of a new phaco tip design during cataract surgery. 100 patients were assigned to two groups. In group 1 (50 patients), the Kelman® tip design (Alcon) was used during phacoemulsification, while in group 2 (50 patients), the Intrepid® Balanced Tip was applied. Trypan blue was used in both groups, if necessary, to stain the anterior lens capsule prior to capsulorhexis. Preoperative visual acuity was 0.11 ± 0,16 (decimal equivalent; means ± standard deviation) in the Kelman tip group and 0.10 ± 0.14 in the Intrepid Balanced Tip group (p > 0,05). Applied cumulative displaced energy was 43.38 ± 21.84 s% in the Kelman tip group and 21.55 ± 13.25 s% in the Intrepid Balanced Tip group (p < 0,001). No intraoperative or postoperative complications occurred. The improved Intrepid Balanced phaco tip design has led to a significant reduction in ultrasound energy required to successfully perform phacoemulsification in medium to hard lenses.