Comparison of penetrating femtosecond laser-assisted astigmatic keratotomy and toric intraocular lens implantation for correction of astigmatism in cataract surgery.

This study tried to compare the clinical outcomes of femtosecond laser-assisted astigmatic keratotomy (FSAK) and toric intraocular lens (IOL) implantation for astigmatism correction and identify factors affecting the efficacy of FSAK and toric IOL implantation in astigmatism correction. This retrospective case series comprised patients with corneal astigmatism ranging between 0.5 D and 4.5 D. Patients underwent FSAK or toric IOL implantation for cataract treatment and correction of astigmatism at the Samsung Medical Center, a tertiary surgical center, between April 2016 and December 2018. All patients underwent examination before and at three months after the surgery for comparative evaluation of refractive astigmatism, corneal high order aberrations and irregularity index. The astigmatism correction was analyzed by the Alpins method. Subgroup analysis of preoperative factors was based on the extent of target-induced astigmatism (TIA), the degree of astigmatism, and astigmatism classification based on topography. Thirty-one eyes underwent toric IOL implantation and 35 eyes underwent FSAK. The refractive astigmatism was significantly decreased in both toric IOL (P = 0.000) and FSAK group (P = 0.003). The correction index (CI) of refractive astigmatism was 0.84 ± 0.39 in the toric IOL and 0.71 ± 0.60 in the FSAK group. There was no difference between the two groups (P = 0.337). The CI of the FSAK group was significantly lower than in the toric IOL group when TIA was more than 1.5 D (P = 0.006), when correcting against-the-rule (P = 0.017), and limbus-to-limbus astigmatism (P = 0.008). In conclusion, toric IOL implantation is an effective and safe procedure for correcting preoperative astigmatism in cataract surgery in the short-term observation.

Comparison of phacoemulsification parameters in eyes with and without exfoliation syndrome.

OBJECTIVE: To evaluate and to compare the phacoemulsification machine parameters in eyes with and without XFS, requiring cataract surgery. METHODS: Patients who underwent phacoemulsification and in-the-bag IOL implantation for cataract were included in this retrospective study. All surgeries were performed by the same experienced surgeon using the stop & chop technique with the same phacoemulsification device (Infiniti Vision System, Alcon Laboratories, Inc., USA). Patients were divided into two groups according to the presence of exfoliation material (XFM). Each group consisted of consecutive patients. Their characteristics and intraoperative phacoemulsification parameters were compared. RESULTS: Sixty-eight eyes of 68 patients [29 in the exfoliation syndrome (XFS) (-) group, 39 in XFS (+)] were enrolled. There were no statistical differences regarding preoperative patient characteristics. There was a statistically significant difference in total U/S time, phaco time, aspiration time and estimated fluid used between the XFS (+) and XFS (-) groups (P=0.021, P=0.017, P=0.009 and P=0.002, respectively). Considering that the use of a CTR (capsule tension ring) might be an important factor potentially affecting surgical parameters, the data were analyzed accordingly. Aspiration time and estimated fluid used remained statistically significant (P=0.046 and P=0.017, respectively); however, although the U/S total and phaco time were found to be longer in XFS (+) group compared to XFS (-) group, the difference did not show statistical significance (P=0.061 and P=0.059, respectively). There were no differences between groups regarding endothelial cell loss or any other postoperative complications. CONCLUSIONS: The presence of XFS results in longer total U/S time, phaco and aspiration time and more estimated fluid used in phacoemulsification, but this prolongation does not result in additional complications.

Experience in cataract surgery assisted by femtosecond laser at Fundación Hospital Nuestra Señora de la Luz.

OBJECTIVE: To describe the transoperative results of cataract surgeries assisted by femtosecond laser. METHOD: Observational, descriptive, retrospective and cross-sectional study of 420 surgical records made with the LenSx platform from April 2015 to August 2017. The review of records was made through the internal electronic system accessing the preoperative and postoperative note. The information was collected through a database in Excel. The analysis of variables was performed by means of descriptive statistics with measures of central tendency. RESULTS: 86 files met inclusion criteria. The average age was 63 years. There was a general frequency of complications of 27.9% (24 surgeries). The most frequent complications were incomplete or impermeable corneal wound (37.5%), incomplete capsulorhexis (25%) and posterior capsule rupture (16.7%). CONCLUSIONS: The femtosecond laser technology incorporated in cataract surgery can be considered successful because of a low overall frequency of complications.

OBJETIVO: Describir las complicaciones transoperatorias de las cirugías de catarata asistidas por láser de femtosegundo. MÉTODO: Estudio observacional, descriptivo, retrospectivo y transversal de 420 expedientes de cirugías realizadas con la plataforma LenSx de abril de 2015 a agosto de 2017. La revisión de expedientes se realizó a través del sistema electrónico interno accediendo a las notas preoperatoria y posoperatoria. La información se recopiló en una base de datos Excel. Se realizó el análisis de variables por medio de estadística descriptiva con medidas de tendencia central. RESULTADOS: Cumplieron criterios de inclusión 86 expedientes. La edad promedio de los pacientes fue de 63 años. Se presentó una frecuencia general de complicaciones del 27.9% (24 cirugías). Las complicaciones que ocurrieron con mayor frecuencia fueron herida corneal incompleta o impermeable (37.5%), capsulorrexis incompleta (25%) y rotura de cápsula posterior (16.7%). CONCLUSIONES: La tecnología de láser de femtosegundo incorporada en la cirugía de catarata puede considerarse como exitosa al tener una baja frecuencia general de complicaciones.

Comparison of Using One Trabecular Microbypass Stent versus Two during Cataract Surgery at Two Sites: One-Year Follow-Up.

PURPOSE: To compare IOP and ocular hypotensive medication reduction of using one trabecular microbypass stent versus two in patients with open-angle glaucoma. Setting. Palo Alto Veterans Affairs (VA) Hospital and the Byers Eye Institute at Stanford University, Palo Alto, California, USA. DESIGN: Retrospective case series. METHODS: A chart review included patients who underwent trabecular microbypass implantation with cataract surgery in 2015-2017, with at least one-year follow-up. Subjects were divided into two groups by location (always one stent at Stanford versus two stents at the VA). Primary outcome measures included IOP and medication reduction at baseline and 12-month follow-up. RESULTS: 132 subjects (166 eyes) were included. The preoperative IOP was 16.3 ± 3.4 mmHg on 2.6 ± 1.1 medications in the one-stent group (N = 85) and 17.5 ± 3.1 mmHg on 2.7 ± 0.6 medications in the two-stent group (N = 81). There was no significant difference between the two groups (p = 0.06). At the 12-month visit, there was a 13.37% ± 2.93 reduction in IOP in the 1-stent group (p ≤ 0.001) and 13.49% ± 2.69 in the 2-stent group (p ≤ 0.001); both were not significantly different from each other (p = 0.074). At 12 months, there was also a 14.5% reduction in medication use for the 1-stent group and 15.3% reduction in the 2-stent group, both statistically significant from baseline, (p = 0.022 and p = 0.037, respectively). CONCLUSIONS: Implantation with either one or two stents during cataract surgery in patients with glaucoma demonstrated similar IOP and med reduction in both groups between the two sites.

Evaluation of the Protective Effect of an Ophthalmic Viscosurgical Device on the Ocular Surface in Dry Eye Patients during Cataract Surgery.

PURPOSE: To evaluate the protective effect of applying an ophthalmic viscosurgical device (OVD) to the ocular surface during cataract surgery and its ability to prevent dry eye syndrome. METHODS: Twenty-four patients aged 50 to 75 years who underwent cataract surgery at Seoul National University Bundang Hospital and agreed to participate in the study were included and divided into two groups: a study group who underwent cataract surgery after application of an OVD to the ocular surface, and a control group who underwent cataract surgery without application of an OVD. DisCoVisc was used as the OVD in the study group, while other factors including surgical techniques and administration of anesthetic agents were performed in both groups in the same manner. Indicators of dry eye syndrome including ocular staining score, tear break-up time, and tear osmolality were analyzed. Ocular surface disease index and a visual analog scale were analyzed for dry eye symptoms, and the amount of balanced salt solution used during surface irrigation and operation time were also analyzed. RESULTS: Significant improvement in the tear break-up time, corneal ocular staining score, and ocular surface disease index score in the study group compared with the control group one week after operation (by the Mann-Whitney test). Use of OVD was associated with longer operating time. CONCLUSIONS: OVD applied to the ocular surface during cataract surgery had a protective effect on the ocular surface one week after surgery.

Assessment of Automated Identification of Phases in Videos of Cataract Surgery Using Machine Learning and Deep Learning Techniques.

Importance: Competence in cataract surgery is a public health necessity, and videos of cataract surgery are routinely available to educators and trainees but currently are of limited use in training. Machine learning and deep learning techniques can yield tools that efficiently segment videos of cataract surgery into constituent phases for subsequent automated skill assessment and feedback. Objective: To evaluate machine learning and deep learning algorithms for automated phase classification of manually presegmented phases in videos of cataract surgery. Design, Setting, and Participants: This was a cross-sectional study using a data set of videos from a convenience sample of 100 cataract procedures performed by faculty and trainee surgeons in an ophthalmology residency program from July 2011 to December 2017. Demographic characteristics for surgeons and patients were not captured. Ten standard labels in the procedure and 14 instruments used during surgery were manually annotated, which served as the ground truth. Exposures: Five algorithms with different input data: (1) a support vector machine input with cross-sectional instrument label data; (2) a recurrent neural network (RNN) input with a time series of instrument labels; (3) a convolutional neural network (CNN) input with cross-sectional image data; (4) a CNN-RNN input with a time series of images; and (5) a CNN-RNN input with time series of images and instrument labels. Each algorithm was evaluated with 5-fold cross-validation. Main Outcomes and Measures: Accuracy, area under the receiver operating characteristic curve, sensitivity, specificity, and precision. Results: Unweighted accuracy for the 5 algorithms ranged between 0.915 and 0.959. Area under the receiver operating characteristic curve for the 5 algorithms ranged between 0.712 and 0.773, with small differences among them. The area under the receiver operating characteristic curve for the image-only CNN-RNN (0.752) was significantly greater than that of the CNN with cross-sectional image data (0.712) (difference, -0.040; 95% CI, -0.049 to -0.033) and the CNN-RNN with images and instrument labels (0.737) (difference, 0.016; 95% CI, 0.014 to 0.018). While specificity was uniformly high for all phases with all 5 algorithms (range, 0.877 to 0.999), sensitivity ranged between 0.005 (95% CI, 0.000 to 0.015) for the support vector machine for wound closure (corneal hydration) and 0.974 (95% CI, 0.957 to 0.991) for the RNN for main incision. Precision ranged between 0.283 and 0.963. Conclusions and Relevance: Time series modeling of instrument labels and video images using deep learning techniques may yield potentially useful tools for the automated detection of phases in cataract surgery procedures.

Incidence of pseudophakic cystoid macular edema in eyes with and without pupil expansion device.

PURPOSE: Novel pupil expansion devices are widely recognized for their intraoperative feasibility in safe small pupil cataract surgeries. To assess whether the use of pupil expansion devices affects recovery from cataract surgery. METHODS: A post hoc analysis of five consecutive prospective randomized clinical trials. 536 eyes of 536 patients undergoing routine cataract surgery were analysed according to the use of pupil expansion device. Thirty-four eyes were operated with pupil expansion device and 502 eyes without. Clinical outcome parameters were recorded at 28 days and 3 months. RESULTS: Patient age and gender distribution, and baseline clinical outcome parameters were comparable between study groups. Pseudoexfoliation syndrome, glaucoma and medication for benign prostatic hyperplasia were more frequently present; phacoemulsification energy was higher and operation time longer in eyes with pupil expansion device. At 28 days, aqueous flare increased by 12.0 ± 25.1 pu/mseconds and mean central subfield macular thickness by 16.2 ± 24.4 µm in eyes with pupil expansion device, when compared to 4.6 ± 14.8 pu/mseconds (p = 0.015) and 7.0 ± 33.9 µm (p = 0.064) in eyes without the device. At 3-month follow-up, clinically significant pseudophakic cystoid macular edema (PCME) was reported in 12% of eyes with pupil expansion device and in 2% of eyes without (p = 0.006). After adjusting for the presence of confounding factors, hazard for clinically significant PCME was greater in eyes with pupil expansion device than in those without (HR 5.41, 95% CI 1.35-21.71, p = 0.017). CONCLUSIONS: The use of pupil expansion device may predispose eyes to increased risk of clinically significant PCME. Effective anti-inflammatory treatment and follow-up are warranted in eyes with pupil expansion device.

CATARACTS: Challenge on automatic tool annotation for cataRACT surgery.

Surgical tool detection is attracting increasing attention from the medical image analysis community. The goal generally is not to precisely locate tools in images, but rather to indicate which tools are being used by the surgeon at each instant. The main motivation for annotating tool usage is to design efficient solutions for surgical workflow analysis, with potential applications in report generation, surgical training and even real-time decision support. Most existing tool annotation algorithms focus on laparoscopic surgeries. However, with 19 million interventions per year, the most common surgical procedure in the world is cataract surgery. The CATARACTS challenge was organized in 2017 to evaluate tool annotation algorithms in the specific context of cataract surgery. It relies on more than nine hours of videos, from 50 cataract surgeries, in which the presence of 21 surgical tools was manually annotated by two experts. With 14 participating teams, this challenge can be considered a success. As might be expected, the submitted solutions are based on deep learning. This paper thoroughly evaluates these solutions: in particular, the quality of their annotations are compared to that of human interpretations. Next, lessons learnt from the differential analysis of these solutions are discussed. We expect that they will guide the design of efficient surgery monitoring tools in the near future.

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.

Intraocular robotic interventional surgical system (IRISS): Semi-automated OCT-guided cataract removal.

BACKGROUND: With the development of laser-assisted platforms, the outcomes of cataract surgery have been improved by automating several procedures. The cataract-extraction step continues to be manually performed, but due to deficiencies in sensing capabilities, surgical complications such as posterior capsule rupture and incomplete cataract removal remain. METHODS: An optical coherence tomography (OCT) system is integrated into our intraocular robotic interventional surgical system (IRISS) robot. The OCT images are used for preoperative planning and intraoperative intervention in a series of automated procedures. Real-time intervention allows surgeons to evaluate the progress and override the operation. RESULTS: The developed system was validated by performing lens extraction on 30 postmortem pig eyes. Complete lens extraction was achieved on 25 eyes, and "almost complete" extraction was achieved on the remainder due to an inability to image small lens particles behind the iris. No capsule rupture was found. CONCLUSION: The IRISS successfully demonstrated semiautomated OCT-guided lens removal with real-time supervision and intervention.

Trans-scleral explantation of posteriorly dislocated IOL-CTR complex in a case of anterior megalophthalmos with an unusually thin cornea.

Anterior megalophthalmos and keratoglobus are characterised by corneal thinning and deep anterior chamber. They are clinically distinguished on the basis of normal to slightly decreased corneal thickness with a large corneal diameter (>13 mm) in case of anterior megalophthalmos, and marked limbus-to-limbus corneal thinning with globular protrusion in keratoglobus. To achieve and maintain a centred and stable intraocular lens (IOL) position in the bag is often difficult in cases of anterior megalophthalmos due to a too large diameter of the capsular bag and ciliary ring. We report a case of a 40-year-old man with features of anterior megalophthalmos with extremely thin cornea. He had spontaneous posterior dislocation of IOL and capsular tension ring (CTR) within the bag after initial successful cataract surgery. The dislocated complex could neither have been repositioned with scleral fixation due to large diameter of ciliary ring nor could it have been explanted through a clear corneal incision due to associated very thin cornea. We performed pars plana vitrectomy and separated the IOL-CTR complex inside the eye and explanted them separately through the sclerotomy, as is done for removal of intraocular foreign body. This avoided incision on the thin cornea. We conclude that this method can be very useful in a similar clinical situation but is complex enough to justify its use in routine cases.

Crystalline lens endocapsular fragmentation using an elastic loop filament.

PURPOSE: To describe a novel mechanical endocapsular fragmentation technique of the crystalline lens during cataract surgery using a loop elastic-thin filament. METHODS: An alternative method to mechanically fragment the crystalline lens utilizing a nitinol loop is described. This device achieves lens sectioning in multiple pieces, decreasing ultrasonic energy expenditure during cataract surgery. RESULTS: Endocapsular fragmentation of crystalline lens was achieved using a nitinol loop filament, without the use of ultrasound energy. CONCLUSION: This surgical technique demonstrates that a micro loop filament may be used as an alternative surgical approach for energy-free mechanical endocapsular nucleus disassembly and fragmentation.

[Posterior capsule opacification, glistenings and visual outcomes: 3 years after implantation of a new hydrophobic IOL]. / Performances visuelles, glistening et opacification capsulaire postérieure : 3 ans après l'implantation d'un nouvel implant hydrophobe.

PURPOSE: To evaluate the visual outcomes, the incidence of glistenings and posterior capsule opacification in a series of consecutive eyes with a new blue light-filtering hydrophobic acrylic intraocular lens (IOL) SETTING: Service d'ophtalmologie, clinique Beausoleil, avenue de Lodève, Montpellier. DESIGN: Retrospective, cross-sectional study. METHODS: This study included a series of 66 eyes that underwent routine cataract surgery with PODEye (PhysIOL SA, Liège, Belgium) monofocal IOL implantation between May 2011 and November 2011. These eyes were compared for glistenings with patients implanted with Acrysof material IOL (Alcon, Fort Worth, USA) who had a routine postoperative examination between January 2015 and August 2015. The safety of the IOL was assessed by visual acuity outcomes, as well as rotational stability, centration and postoperative medication. The incidence and severity of glistenings were evaluated with the slit lamp. Glistenings and PCO were graded subjectively (0=absent; 1=moderate; 2=dense). Follow-up was 3 years. RESULTS: The mean visual acuity after PODEye implantation was 0.98±0.05 (n=50) in decimal notation at 1 year, 0.98±0.06 at 1 week, (n=66), 1.00±0.01 at 3 weeks (n=64) and 0.99±0.02 at 3 months (n=59). The IOL displayed stable positioning in all axes. Glistenings of grade 2 were absent in the G-Free/PODEye group, whereas they were significantly present in the Acrysof group. One out of 43 eyes at 3-year follow-up underwent YAG capulotomy at 37 months. Sixty-six percent of eyes had no PCO (grade 0) at 3 years. CONCLUSIONS: The PODEye IOL was safe and stable. Glistenings grade 2 or more were not found with this blue light-filtering hydrophobic acrylic IOL. PCO occurrence was low at three years.

Quantifying the real-world cost saving from using surgical adjuncts to prevent complications during cataract surgery.

INTRODUCTION: Surgical adjuncts in cataract surgery are often perceived as sometimes necessary, always expensive, particularly in the "lean" cost-saving era. However, prevention of a surgical complication, rather than subsequent management, should always be the preferred strategy. We wished to model real-world costs associated with surgical adjuncts use and test the maxim for cataract surgery-"if you think of it, use it". METHODS: We compared UK list prices for equipment and related costs of preventing vitreous loss (VL) via use of surgical adjuncts vs its subsequent management in a hypothetical cataract surgery scenario of a white swollen cataract with a moderately dilated pupil. RESULTS: The original surgery costs for the "cautious with adjuncts, no complications" approach was £943.54, including adjuncts costing £137.47. In the "minimalist, no adjunct" scenario, management of VL using the Anterior Vitrectomy Kit cost £142.45, and additional management and follow-up costs resulted in total cost of £1178.20 (£234.66 (25%) more expensive). If left aphakic, an additional operation for secondary iris clip IOL insertion and further follow-up to address the impact of the complication ultimately cost £2124.67 overall. An additional initial spend on surgical adjuncts of £137.47 could potentially prevent £1293.60 (9× increase) in direct costs in this scenario. CONCLUSIONS: Through simple scenario modelling, we have demonstrated the cost benefits provided by the use of precautionary surgical adjuncts during cataract surgery. VL costs significantly more in terms of complication management and follow-up. This supports the cataract surgeon's maxim-"if you think of it, use it".

Efficacy of the Canabrava Ring (pupil expansion device) in cataract surgery for eyes with small pupils: the first 30 cases.

PURPOSE: To evaluate the outcomes of the first 30 cataract surgeries performed with a new disposable, injector-free, small-pupil expansion device. METHODS: This consecutive case series included 30 eyes from 29 patients who underwent cataract surgery using a new disposable small-pupil expansion device called the Canabrava Ring (AJL Ophthalmic S.A, Spain). It is the first iris expansion ring produced with indents that do not align with each other in the superior and inferior regions, resulting in a small vertical length (0.4 mm) that minimizes the risk of endothelial contact. All eyes had poorly dilated pupils of less than 5 mm preoperatively. Fifteen eyes had significant infective or traumatic pathologies preoperatively. Vertical and horizontal pupil diameters were evaluated preoperatively, intraoperatively, and 1 month postoperatively. RESULTS: The mean patient age was 64 ± 11.8 (standard deviation) years. The Canabrava Ring remained engaged throughout all surgeries, except one. All pupils were intraoperatively expanded to a diameter of 6.3 mm. Although preexisting pathology on the innervation of the pupils, the mean pupil diameter returns to a close preoperative size after 1 month surgery. The mean pupil diameters postoperatively and preoperatively were 4.41 and 3.77 mm, respectively (p<0.05). Postoperative complications occurred in eight eyes (one toxoplasmosis reactivation, one retinal detachment, one posterior capsule rupture, one posterior capsule opacification, and four posterior synechiae). These complications occurred in eyes with preexisting traumatic or infective pathologies or synechiae. CONCLUSION: The Canabrava Ring is effective for expanding and maintaining expansion of small pupils in cataract surgery. The increase in postoperative pupil diameter is clinically diminutive and can most likely be attributed to preexisting pathologies affecting pupil innervation. Further large-scale studies are required to support the present findings.