[Optimization of phacoemulsification technique for Morgagnian cataract]. / Optimizatsiya tekhnologii fakoemul'sifikatsii morganievoi katarakty.

PURPOSE: This study was conducted to develop a new optimized phacoemulsification technique for Morgagnian cataract taking into account the anatomical and topographic parameters of the lens nucleus. MATERIAL AND METHODS: A working classification of Morgagnian cataract was developed based on the size of the nucleus: if the edge of the nucleus is visualized at the upper edge of the pupil or between the upper edge and the middle of the pupil, it was classified as an initial stage of Morgagnian cataract with a large nucleus; if the upper edge of the nucleus is visualized in the middle of the pupil and below, it was classified as an advanced stage of Morgagnian cataract with a small nucleus. The first group included six patients who underwent surgery using the scaffold technique with removal of the whole small nucleus into the anterior chamber. The second group included 11 patients who underwent surgery using the scaffold technique with removal of the last fragment of the nucleus into the anterior chamber. RESULTS: The use of the scaffold technique with removal of the nucleus into the anterior chamber helped reduce the number of intraoperative complications to 16.7% in the first group, compared to 27.3% in the second group, and the percentage of endothelial cell loss to 10.1% in the first group, compared to 10.7% in the second group. CONCLUSIONS: The anatomical and topographic features of the lens and the anterior segment of the eye in Morgagnian cataract with a small nucleus allow for preliminary implantation of an intraocular lens into the capsular bag to protect the posterior capsule during phacoemulsification of the nucleus with minimal mechanical, hydrodynamic and acoustic damage to the surrounding structures of the eye.

[Rotational technique for emulsification of soft lens nucleus]. / Rotatsionnaya metodika emul'sifikatsii myagkogo yadra khrustalika.

Effective and atraumatic removal of a soft lens nucleus requires different surgical techniques compared to phacoemulsification of a dense nucleus. PURPOSE: This study was conducted to develop a non-ultrasound technique for emulsification of a soft lens nucleus. MATERIAL AND METHODS: Fifty-seven patients (57 eyes) underwent surgery. In 23 cases, early or immature cataracts were detected, and in 34 cases, lens removal was performed for refractive purposes in high myopia and complex myopic astigmatism. Phacoemulsifier Centurion Vision System (Alcon Laboratories, Inc., USA) was used for the surgery. Aspiration of soft lens nucleus was done using a rotational technique. The following aspects were evaluated in the course of the surgery: the volume of the required irrigation solution, and the frequency needing to involve ultrasound for complete emulsification of the lens nucleus. Intraoperative and postoperative complications were also assessed. RESULTS: The surgery was uneventful in all cases. There were no violations of the integrity of capsulorhexis edge. The need for short pulses of minimal power ultrasound during the removal of the soft lens using this technique arose only in 11 (19.3%) cases. The effective ultrasound time was less than 1 second. The required volume of irrigation solution was 33.0 (24.0; 43.0) ml, which does not differ significantly from that in ultrasonic phacoemulsification. CONCLUSIONS: The use of modern phacoemulsifiers providing a high vacuum level allows successful removal of a soft lens without using ultrasound, which prevents its negative impact on the ocular tissues. The use of adequate surgical techniques, including the optimal direction of rotation of the lens nucleus in the rotational technique, improves the efficiency of soft lens nucleus removal.

[Influence of the pattern of femtosecond laser-assisted lens nucleus fragmentation on the energy and hydrodynamic parameters of phacoemulsification]. / Vliyanie patterna fragmentatsii yadra khrustalika femtosekundnym lazerom na energeticheskie i gidrodinamicheskie parametry fakoemul'sifikatsii.

The influence of various patterns of preliminary femtosecond laser-assisted fragmentation of the lens nucleus on the energy and hydrodynamic parameters of phacoemulsification remains insufficiently studied. PURPOSE: This study evaluates the influence of various patterns of preliminary femtosecond laser-assisted fragmentation of the lens nucleus on the energy, hydrodynamic parameters of phacoemulsification, and the degree of corneal endothelial cell loss. MATERIAL AND METHODS: Hybrid phacoemulsification was performed in 336 patients (336 eyes) with grade IV immature cataract according to the Buratto classification in three age-matched groups. Group 1 included 103 patients (103 eyes) who underwent hybrid phacoemulsification with preliminary femtosecond laser-assisted fragmentation of the nucleus with a «pizza¼ pattern (division of the nucleus with 10 radial cuts). Group 2 included 112 patients (112 eyes) who underwent femtosecond laser-assisted fragmentation of the nucleus with a «cylinders¼ pattern (division of the nucleus with 8 radial cuts in combination with 5 circular cuts). Group 3 included 121 patients (121 eyes) who underwent femtosecond laser-assisted fragmentation of the nucleus with a «grid¼ pattern (division of the nucleus with 8 radial cuts in combination with multiple mutually perpendicular cuts in the central zone in the form of a grid with a 0.5 mm cell). Effective ultrasound time and the volume of irrigation solution for emulsification of the lens nucleus fragments were determined during the operation. The loss of corneal endothelial cells was assessed 3 months after surgery. RESULTS: The minimum effective ultrasound time was noted after using the "grid" pattern - 4.05 (2.88; 4.74) s, which was significantly less than with the "cylinders" pattern - 4.97 (3.78; 5.88) s and the "pizza" pattern - 6.15 (4.52; 7.75) s (p<0.05). The effective ultrasound time when using the "cylinders" pattern was significantly less than with the "pizza" pattern (p<0.05). The volume of irrigation solution used for emulsification of the lens nucleus fragments was significantly less in the "grid" pattern - 41.5 (33.5; 49.5) ml compared to the "cylinders" patterns 58.5 (51.0; 66.0), p<0.05 and "pizza" pattern 75.0 (66.0; 83.5), p<0.01. The volume of irrigation solution when using the "cylinders" pattern was significantly less than when using the "pizza" pattern (p<0.05). The loss of corneal endothelial cells after using the "grid" pattern was 8.82 (7.59; 9.87)%, which was significantly less than after the "cylinders" patterns - 9.97 (8.81; 10.83)%, p<0.05 and "pizza" - 11.70 (10.62; 12.97)%, p<0.05. At the same time, the loss of endothelial cells after using the "cylinders" pattern was significantly less than after the "pizza" pattern (p<0.05). CONCLUSIONS: The choice of the optimal pattern of preliminary femtosecond laser-assisted fragmentation of the lens nucleus provides a significant decrease in the energy and hydrodynamic parameters of phacoemulsification and, accordingly, the loss of corneal endothelial cells.

[Surgical technique for aspiration of soft lens nucleus with preoperative femtosecond laser-assisted fragmentation]. / Khirurgicheskaya tekhnika aspiratsii myagkogo yadra khrustalika s predvaritel'noi femtolazernoi fragmentatsiei.

Fragmentation and aspiration of soft cataracts require different surgical techniques and approaches compared to the removal of dense nuclei, including when using a femtosecond laser. PURPOSE: This study was conducted to develop a non-ultrasound technique for aspiration of a soft lens nucleus after its preliminary femtosecond laser-assisted fragmentation. MATERIAL AND METHODS: The study included 63 patients (63 eyes) aged 23 to 40 years who underwent surgery. In 27 cases, early or immature cataract was observed, and in 36 cases, cataract removal was performed for refractive purposes in high myopia and complex myopic astigmatism. The VICTUS femtosecond laser surgical system (Technolas Perfect Vision GmbH, Germany) was used for preliminary fragmentation of the lens nucleus. Surgeries were performed using the Centurion Vision System phacoemulsifier (Alcon Laboratories, Inc., USA). The volume of the required irrigation solution was evaluated during the surgery. Intraoperative and postoperative complications were assessed. RESULTS: The surgery was performed without complications in all cases. Capsulorhexis edge was completely preserved along its entire circumference. The study showed the fundamental possibility of aspirating a cataract with a nucleus of grade I-II density without low-frequency ultrasound after preliminary femtosecond laser-assisted fragmentation of the nucleus with a "grid" pattern, which ensures minimal fragment size in the central zone of the nucleus. The volume of irrigation solution required for aspiration of the nucleus was 36.0 (27.0; 44.0) ml, which does not significantly differ from the volume of solution during ultrasound phacoemulsification of a nucleus of such density. CONCLUSIONS: Femtosecond laser-assisted fragmentation of the lens nucleus with a "grid" pattern and phacoemulsifier systems with a high vacuum level allow effective aspiration of a soft lens without using low-frequency ultrasound.

Evaluation of efficacy of new lens nucleus fragmenting forceps in cataract surgery / Avaliação da eficácia de uma nova pinça fragmentadora de núcleo do cristalino para cirurgia de catarata

ABSTRACT Objective: To evaluate the efficacy of low-cost nucleus fragmenting forceps designed to reduce the use of ultrasound during phacoemulsification. Methods: A total of 60 pig eyes enucleated 10 hours before were placed in the microwave oven, at maximum power for 10 seconds, to form cataracts with hardness comparable to a grade IV nucleus in the Lens Opacities Classification System III. Cataract extraction was performed using the Centurion® phacoemulsifier (Alcon Laboratories, Geneve, Switzerland) and Leica M620 microscope. All eyes were submitted to the pre-chop technique dividing the nucleus into four parts. After the pre-chop, the quadrants in 30 eyes were phacoemulsified with the torsional mode and were fragmented in the remaining 30 eyes after the pre-chop was with the fragmentation forceps before torsional mode phacoemulsification. The device was calibrated for all eyes by applying the following parameters: 40% linear torsional phacoemulsification; intraocular pressure of 65 mmHg; the linear vacuum of 600 mmHg; aspiration flow of 40 ccs/minute. After each procedure, the following was recorded: cumulative dissipated energy; equivalent average torsional amplitude; equivalent average ultrasonic power; estimated aspirated fluid; ultrasound total time; and total aspiration time. Statistical analysis was performed using the Kruskal-Wallis test and the IBM Statistical Package for Social Sciences. The p-value <0.05 was considered statistically significant. Results: There was a statistically significant reduction favoring the use of the nucleus fragmenting forceps in all parameters, except for the average torsional amplitude. Conclusion: The use of the nucleus fragmenting forceps contributed to improving the efficacy of torsional phacoemulsification in enucleated pig eyes.

RESUMO Objetivo: Avaliar a eficácia de uma pinça fragmentadora de núcleo, de baixo custo, desenvolvida para reduzir o uso de ultrassom durante a emulsificação do núcleo. Métodos: Sessenta olhos de porco com 10 horas de enucleação foram colocados no forno de microondas, em potência máxima por 10 segundos, para a formação de catarata com dureza comparável à de um núcleo grau IV na Lens Opacities Classification System III. A extração da catarata foi realizada com o facoemulsificador Centurion® (Alcon Laboratories, Genebra, Suíça) e microscópio Leica M620. Todos os olhos foram submetidos a técnica de pre-chop, dividindo o núcleo em quatro partes. Em 30 olhos, após o pre-chop, foi feita a facoemulsificação dos quadrantes com o modo torsional e, nos outros 30 olhos, após o pre-chop, cada quadrante foi fragmentado com a pinça antes da facoemulsificação com o modo torsional. O aparelho foi calibrado para todos os olhos com os seguintes parâmetros: faco torsional linear 40%; pressão intraocular 65 mmHg; vácuo linear 600mmHg e fluxo de aspiração 40cc/minuto. Após cada procedimento, verificaram-se energia dissipada acumulada; média da amplitude do faco torsional; média equivalente do poder ultrassônico; líquido aspirado estimado; tempo total de ultrassom e tempo total de aspiração. A análise estatística foi realizada utilizando o teste de Kruskal-Wallis com o IBM Statistical Package for Social Sciences. Valor de p<0,05 foi considerado estatisticamente significante. Resultados: Houve redução estatisticamente significante em favor do uso da pinça fragmentadora de núcleo em todos os parâmetros, menos na média de amplitude do faco torsional. Conclusão: O uso da pinça fragmentadora de núcleo contribuiu para melhorar a eficácia do faco torsional em olhos de porco enucleados.

Visualization of the posterior surface of the lens nucleus with triamcinolone acetonide in phacoemulsification.

PURPOSE: We report a novel technique for visualizing the posterior surface of the lens nucleus during phacoemulsification. SURGICAL TECHNIQUE: Hydro-dissection was performed using a solution of 20 mg triamcinolone acetonide powder without preservatives mixed with 3 ml BSS-plus, and triamcinolone acetonide was clearly identifiable underneath the posterior surface of the lens nucleus. Using a phaco-tip, the nucleus was shaved to the level of the triamcinolone acetonide and could be easily divided. The remnant triamcinolone acetonide was aspirated as much as possible from the lens cortex with an infusion/aspiration tip. SUBJECTS AND EVALUATION TECHNIQUE: Twenty-eight eyes in 28 patients with cataracts were enrolled in this study. Triamcinolone acetonide-assisted phacoemulsification was performed in 13 eyes in 13 patients (triamcinolone acetonide-phacoemulsification group), and normal phacoemulsification was performed in 15 eyes in 15 patients (phacoemulsification group). Intraocular pressure was measured in all patients pre-operatively, 1 day after, and 1 week after surgery. Corneal endothelial cell density was measured pre-operatively and 1 month after surgery. The time of surgical phacoemulsification (surgical phaco time) was measured from the video of the surgery. RESULTS: Surgery was successively performed in all eyes. Pre-operative and post-operative intraocular pressures and cell densities did not significantly differ between the two groups. Surgical phaco time was shorter in the triamcinolone acetonide-phacoemulsification group than in the phacoemulsification group (157.1 ± 51.7 s vs 225.3 ± 45.1 s; p = 0.006). CONCLUSION: The triamcinolone acetonide-assisted phacoemulsification procedure is safe and useful for visualizing the posterior surface of the lens nucleus and facilitates removal of the lens nucleus by phacoemulsification.

Comparison of power-free-chop and phaco-chop techniques for moderate nuclei.

BACKGROUND: To compare the intraoperative and postoperative effects of power-free-chop and phaco-chop techniques for moderate nuclei in phacoemulsification surgery. METHODS: Sixty patients were evaluated in 2 groups. The power-free-chop technique was performed in Group 1 (30 eyes), and the phaco-chop technique was performed in Group 2 (30 eyes). There were no significant differences between these 2 groups. The cumulative dissipated energy (CDE), time to achieve maximum vision, corneal thickness variation, and time to return to the preoperative values were collected. All parameters were statistically compared in these 2 groups by using the chi-square test and the independent-sample t-test. RESULTS: The CDE was 5.53 ± 1.92 J in Group 1 and 7.02 ± 1.77 J in Group 2. After the operation, the mean time to recover to the maximum vision was 2.80 ± 1.42 days in Group 1 and 3.80 ± 1.92 days in Group 2. The mean postoperative corneal thickness increased 36.9 ± 14.74 µm in Group 1 and 46.20 ± 20.67 µm in Group 2. The mean time to return to preoperative pachymetry values was 3.73 ± 1.70 days and 4.83 ± 2.11 days in Group 1 and Group 2, respectively. There were significant differences in these parameters between the groups. CONCLUSIONS: The power-free-chop technique had fewer negative effects on the corneal endothelium, as less ultrasound power was used for moderate nucleus cases. This can accelerate the functional healing process and the return to preoperative physiologic values.

Retrospective study on outcomes of terminal chop technique of nuclear fragmentation in phacoemulsification and combined surgery: An observational study.

PURPOSE: Terminal chop, a new technique of nuclear segmentation, has been recently described in literature. The technique is considered to be a safe and effective option. METHODS: We did a retrospective study to evaluate the outcome of terminal chop. Patients operated for terminal chop (phacoemulsification with or without trabeculectomy) from October 2016 to July 2018 were included in the study. RESULTS: In all, 933 patients were included in the study. The grade of nuclear sclerosis ranged from 2 to 5. All the patients had a significant visual improvement at 1 month postop. Around 3.4% had pseudoexfoliation and 8.89% of the eyes underwent combined surgery. Cumulative dissipated energy showed a proportionate relation with the grade of nucleus. Intraoperative complication rate was 0.08%. Postoperative complication rate was 3.50%. CONCLUSION: Terminal chop proved to be a safe, reproducible, and effective technique of nuclear segmentation in different grades of cataract.

Consecutive drilling combined with phaco chop for full thickness segmentation of very hard nucleus in coaxial microincisional cataract surgery.

BACKGROUND: The complete disassembly of nuclear is the most challenging step in hard cataract surgery through microincision. The classic phaco chop technique often does not succeed, resulting in incomplete nuclear segmentation. The authors describe a technique to improve the efficacy and safety of the initial chopping. METHODS: The consecutive drilling combined with phaco chop technique was devised for very hard cataract through a microincision of 1.8-2.2 mm. 3-4 holes are consecutively drilled into the endonucleus with the phaco tip bevel down, at an angle of approximate 60 degrees and depth of approximately two-thirds of the lens thickness. The initial drilling approaches the capsulorhexis edge and the last drilling approaches the lens geometric center. The nucleus is deeply impaled with the last drilling and firmly engaged with high vacuum, and then chopped with chopper centripetally from the lens equator. The chopper and phaco tip are spread apart laterally after they approach at the center of the nucleus, to create a complete fracture across the entire nucleus. This technique has been adopted in 80 eyes of 65 patients with cataract harder than nuclear opalescence 5 on the Lens Opacities Classification System III scale or mature white cataract with a hard nucleus in the past 12 months. RESULTS: In all cases, full thickness segmentation of the hard nuclear including the posterior plate was achieved with this consecutive drilling combined with phaco chop technique. Phacoemulsification and intracapsular implantation of intraocular lens was safely performed in each case. No intraoperative complication such as iris injury, anterior capsule tears, zonulysis or posterior capsule rupture with vitreous loss occurred during surgery. No postoperative complication such as fibrin formation, synechias, severe endothelial cell loss, or endophthalmitis was observed in any case at 6 months postoperatively. CONCLUSIONS: The technique is an efficient, safe, simple, and swift procedure for full-thickness nuclear segmentation, delivering advantage of microincisional phacoemulsifcation for hard cataract with few ocular complications.

Managing dislocated hard lens nuclei: 23-gauge vitrectomy and lens extraction via a corneoscleral limbal incision versus 23-gauge vitrectomy and phacofragmentation.

PURPOSE: To compare 23-gauge vitrectomy and lens extraction via a corneoscleral limbal incision (CSLI) with 23-gauge vitrectomy and phacofragmentation to treat dislocation of hard lens nuclei. SETTING: Ningbo Eye Hospital, Zhejiang, China. DESIGN: Retrospective case series. METHODS: The study included consecutive patients with complete posterior dislocation of a hard nucleus (grade ≥ IV) into the vitreous cavity. All patients received 23-gauge 3-channel vitrectomy. Some patients also had phacofragmentation and others had lens extraction through a CSLI. RESULTS: The CSLI group comprised 21 eyes of 21 patients and the phacofragmentation group, 22 eyes of 22 patients. The median follow-up was 10.8 months (range 6 to 24 months) and 11.3 months (range 5 to 18 months), respectively. Demographic characteristics, reason for lens dislocation, preoperative corrected distance visual acuity (CDVA), preoperative intraocular pressure (IOP), lens nucleus grade, and comorbidities were similar between groups. The CSLI group had a shorter mean surgical time than the phacofragmentation group (42.5 ± 7.2 minutes versus 68.2 ± 16.5 minutes); less frequent use of perfluorocarbon liquid, octafluoropropane, or air tamponade; lower incidence of retinal tears (9.5% versus 31.8%); and better CDVA but worse astigmatism 1 day and 1 week postoperatively (P < .05). The postoperative IOP did not differ between groups. Corneal edema and recurrent retinal detachment were less common in the CSLI group than in the phacofragmentation group. CONCLUSION: The 23-gauge vitrectomy with lens extraction through a CSLI might have advantages over 23-gauge vitrectomy with phacofragmentation for management of dislocated hard lens nuclei.

Central corneal epithelial thickness changes after half-moon supracapsular nucleofractis phacoemulsification technique.

PURPOSE: To find out the effect of half-moon supracapsular nucleofractis technique on central corneal epithelial thickness (CET) measured by spectral domain anterior segment optical coherence tomography (AS-OCT). MATERIALS AND METHODS: Patients who underwent uneventful cataract surgery by the same surgeon with the same technique were recruited in this study. The effective phaco time (EPT) was recorded in each surgery. Central CET was measured by AS-OCT 1 day before and 1, 3, 7 days after surgery. CET was measured without precorneal tear film layer, and non-epithelial central corneal thickness was also calculated manually. Preoperative and postoperative values were compared by statistical analysis. RESULTS: Thirty-one eyes of 31 patients were included in this study. The mean age of patients was 65.03 ± 11.47 years. On the first day of surgery, increase in mean CET was statistically significant, but on the 3rd and 7th day after surgery, this increase was declined (p = 0.001, p = 0.367, p = 1, respectively). A statistically significant positive correlation was found between mean EPT and mean CET on the first postoperative day (p = 0.013, r = 0.470). On the 3rd and 7th day, this correlation was not statistically significant (p = 0.055, p = 0.454, respectively). CONCLUSION: Mean central CET was statistically thicker and positive correlated with EPT on the first postoperative day. But on the 7th day, it declined to preoperative values.

Microinterventional endocapsular nucleus disassembly: novel technique and results of first-in-human randomised controlled study.

AIM: To assess the safety and efficacy of microinterventional endocapsular nuclear fragmentation in moderate to severe cataracts. METHODS: This was a prospective single-masked multisurgeon interventional randomised controlled trial (ClinicalTrials.gov NCT02843594) where 101 eyes of 101 subjects with grade 3‒4+ nuclear cataracts were randomised to torsional phacoemulsification alone (controls) or torsional phacoemulsification with adjunctive endocapsular nuclear fragmentation using a manual microinterventional nitinol filament loop device (miLOOP group). Outcome measures were phacoemulsification efficiency as measured by ultrasound energy (cumulative dispersed energy (CDE) units) and fluidics requirements (total irrigation fluid used) as well as incidence of intraoperative and postoperative complications. RESULTS: Only high-grade advanced cataracts were enrolled with more than 85% of eyes with baseline best corrected visual acuity (BCVA) of 20/200 or worse in either group. Mean CDE was 53% higher in controls (32.8±24.9 vs 21.4±13.1 with miLOOP assistance) (p=0.004). Endothelial cell loss after surgery was low and similar between groups (7‒8%, p=0.561) One-month BCVA averaged 20/27 Snellen in miLOOP eyes and 20/24 in controls. No direct complications were caused by the miLOOP. In two cases, capsular tears occurred during IOL implantation and in all remaining cases during phacoemulsification, with none occurring during the miLOOP nucleus disassembly part of the procedure. CONCLUSIONS: Microinterventional endocapsular fragmentation with the manual, disposable miLOOP device achieved consistent, ultrasound-free, full-thickness nucleus disassembly and significantly improved overall phaco efficiency in advanced cataracts. TRIAL REGISTRATION NUMBER: NCT02843594.

Comparison of two popular nuclear disassembly techniques for cataract surgeons in training: divide and conquer versus stop and chop.

PURPOSE: To compare two common phacoemulsification techniques in the learning curve phase, and their effect on ultrasound energy dissipation. METHODS: One hundred and ten consecutive patients scheduled for cataract surgery with the same surgeon in training were prospectively enrolled. Study was divided in two parts. In the first one, 60 patients were stratified for cataract grade [nuclear opalescence (NO) grade 2-4] and divided in two groups receiving surgery with the divide-and-conquer technique (Group-1) and with the stop-and-chop technique (Group-2). In the second part, 50 patients were stratified according to cataract grade (NO2-6), and the surgeon had to choose one of the two techniques according to personal preference. The primary outcome was the cumulative dissipated energy (CDE). RESULTS: Significant differences of CDE were observed between the NO3 and NO4 cataracts in Group-1. In Group-2, this difference was not significant, suggesting that with more advanced cataracts, the stop-and-chop technique allows less ultrasound use. In the second part of the study, the stop and chop was most frequently used for more advanced cataracts. When considering harder cataracts (NO5-NO6), patients receiving surgery with the divide-and-conquer technique had higher CDE values compared to stop and chop. CONCLUSIONS: Both divide-and-conquer and stop-and-chop techniques are efficient in the learning curve. Stop and chop dissipates less energy in harder nuclei. Once surgeons reach sufficient experience with both techniques, they should switch to a stop-and-chop technique, allowing lower levels of ultrasound energy.

Comparison of phacoemulsification parameters between manual and femtosecond laser-assisted cataract surgery.

OBJECTIVE: To compare the nucleus removal time (NRT) and cumulative dissipated energy (CDE) outcomes of traditional phacoemulsification and femtosecond laser-assisted cataract surgery (FLACS) performed by cornea attendings and fellows. DESIGN: Prospective nonrandomized comparative study. PARTICIPANTS: A total of 410 eyes of 410 patients. METHODS: Nucleus removal time and CDE were recorded from patients who underwent cataract surgery using either FLACS (Catalys, LenSx, or Victus) or traditional phacoemulsification technique performed by 3 cornea attendings and 4 cornea fellows. One-way analysis of variance with Bonferroni post hoc tests and unpaired t tests were used to determine the differences between groups. RESULTS: There was no statistically significant difference in cataract grade between groups. NRT was significantly lower only when using the Catalys system compared with the LenSx and Victus platforms and the traditional surgery, in both the attending group (p = 0.006, p = 0.002, p < 0.000, respectively) and the fellow group (p = 0.049, p = 0.038, p = 0.011, respectively). With respect to CDE, there was no significant difference when using the laser systems compared with the traditional surgery in both attending and fellow groups (p > 0.05). NRT and CDE were significantly higher in the fellow group (NRT = 269.10 ± 117.67, CDE = 7.30 ± 4.83) compared with the attending group (NRT = 218.87 ± 109.67, CDE = 5.76 ± 3.66) in traditional cases; however, in FLACS cases, there was no significant difference in NRT and CDE between the fellow group and the attending group. CONCLUSIONS: Inexperienced surgeons seem to require more time and use more ultrasound energy during traditional phacoemulsification when compared with experienced surgeons. The use of FLACS seems to significantly improve the NRT of experienced and inexperienced surgeons.

Microinterventional endocapsular nucleus disassembly for phacoemulsification-free full-thickness fragmentation.

We describe a new technique for nucleus disassembly using a microinterventional approach. This is the first report of a microinterventional phacoemulsification-free endocapsular lens fragmentation using a superelastic memory-shaped nickel and titanium (nitinol) microfilament (miLOOP). After standard capsulorhexis and hydrodissection, the microinterventional loop is inserted through the 2.3 mm clear corneal incision. An actuation mechanism is used to unfold the microloop, which glides horizontally on the anterior surface of the lens, expands below the anterior capsule, and then rotates vertically while traveling in the hydrodissection plane to encircle the entire nucleus. Then, the loop is mechanically retracted within the sleeve, achieving full-thickness centripetal segmentation of the nucleus. After rotation of the lens, the loop cuts can be repeated to create 4 or more segments without using phaco energy. The technique is independent of cataract grade and eliminates the need for phacoemulsification or femtosecond energy during the nucleus disassembly step of cataract surgery.

Optimum on-time duty cycle for a transversal ultrasound machine.

PURPOSE: To evaluate the optimum on-time setting for the most efficient removal of lens fragments using micropulse ultrasound (US) and Ellips FX transversal US in the Whitestar Signature Pro phacoemulsification machine. 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 cut into 2.0 mm cubes. The US machine was used with a bent 0.9 mm phaco tip and a 30-degree bevel. The off time was set to 6 milliseconds (ms) and the on time varied from 4 to 10 ms in 1 ms increments. Efficiency (time for fragment removal) and chatter (number of times the fragment bounced from the tip) were measured. RESULTS: A linear incremental increase in efficiency was observed between 4 ms and 6 ms. The most statistically significant efficiency was achieved with an on time of 6 ms. On times shorter than 6 ms were significantly less efficient (P = .05). Greater on times (7 to 10 ms) did not result in a significant difference in efficiency (P = .72), but did appear to have more chatter events when comparing on-time settings of 7 to 10 ms with 4 to 6 ms (P = .02). CONCLUSIONS: With micropulse transversal US, 6 ms of on time was as efficient as longer on times. To maximize phacoemulsification efficiency and minimize chatter events, an on time of 6 ms is recommended.

Comparability of subjective and objective measurements of nuclear density in cataract patients.

PURPOSE: To evaluate the relationship between subjective and objective measurements of lens density and the energy of phacoemulsification. SETTING: University Eye Clinic, Maastricht University Medical Centre, Maastricht, the Netherlands. DESIGN: Cross-sectional study. METHODS: The study population included 69 patients. Nuclear opalescence (NO) was graded with the Lens Opacities Classification System III (LOCS III). Thereafter, lens density was measured objectively with Scheimpflug imaging, anterior segment optical coherent tomography and spectral fundus reflectometry (SFR). Cumulative dissipative energy (CDE) and total ultrasound time (US t.t.) of the phacoemulsification were noted. The relationship between the different measurement techniques and energy of phacoemulsification was assessed using Spearman's correlation coefficients. RESULTS: We found moderate to strong correlations between LOCS III and objective measurements of the lens density (rho's from 0.53 to 0.78, p < 0.05) and a moderate correlation between three objective measurement techniques (rho's between 0.29 and 0.57, p < 0.05). There was a moderate correlation between CDE, US t.t. and lens density measurements (rho's from 0.29 to 0.55, p < 0.05), and the highest correlation was found between CDE and NO scores. Exclusion of patients with advanced cortical and posterior subcapsular opacities improved the correlation between SFR and lens density measurements but not the correlation with the energy of phacoemulsification. CONCLUSION: Lens Opacities Classification System III has shown the highest correlation with phacoemulsification energy and may be a preferred technique for prediction of use of phacoemulsification energy. Advanced cortical and posterior opacities may interfere with the quality of objective measurements but do not affect the correlation between lens density measurements and phacoemulsification energy.

Nitinol basket-assisted pars plana vitrectomy for retained lens material removal.

PURPOSE: To evaluate the usefulness of different types of nitinol baskets to capture, lift and hold the lens material, dropped during a complicated phacoemulsification, as an adjunctive surgical tool in vitreoretinal surgery and to evaluate the outcomes and complication of this new surgical technique in a small series of patients. METHODS: Patients who underwent pars plana vitrectomy (PPV) for retained lens fragments operated during December 2014 and March 2015 at the Academic Medical Center (AMC), Amsterdam, were included in this study. The PPV was performed using different settings and types of nitinol stone extractors (NSE). Three different stone extractors were used for the above-mentioned purpose. Preoperative (pre-op) and postoperative (post-op) data including best corrected visual acuity at 6 months follow-up visit, intra- and postoperative complications were recorded. RESULTS: Seven eyes of seven patients with a follow-up of 6 months were included in this study. All the vitrectomies were performed the same day of the complicated cataract extraction. Mean pre-op Snellen visual acuity was 20/160; mean post-op visual acuity was 20/32. No complications were encountered due to the use of the NSE intraocularly. No retinal breaks were observed due to traction of the catheter at the site of insertion or due to his movement in and out the vitreous cavity. CONCLUSION: The use of the nitinol lens cage seemed feasible and showed no complications in our small group of patients. It made easier the management of dropped nucleus without the need for a larger scleral opening also in case of very hard lens.