Ultrastructural Integrity of Human Capsulotomies Created by a Thermal Device.

PURPOSE: To investigate the ultrastructural features of anterior capsulotomy performed with a thermal device, the precision pulse capsulotomy (PPC). DESIGN: Prospective, multicenter case series. PARTICIPANTS: Consecutive patients undergoing capsulotomy with the PPC device. METHODS: Prospective study of patients undergoing capsulotomy with the PPC by 2 surgeons, followed up by routine phacoemulsification cataract surgery, was undertaken. All capsulotomy specimens were collected for scanning electron microscopy (SEM). Observations were made regarding uniformity of the capsular edge and the presence of irregularities that may compromise integrity. Comparisons were made with manual continuous curvilinear capsulorrhexis. MAIN OUTCOME MEASURES: Ultrastructural features of PPC and presence of irregularities. RESULTS: Frayed appearance of the anterior capsule edge was noted in postoperative visits under slit-lamp examination. Scanning electron microscopy sampling showed a generally uniform rolled capsular edge, but interspersed with areas of irregularity with frayed appearance at the capsule margin. CONCLUSIONS: The PPC device is capable of creating reproducible, central, and precise circular capsulotomy. The ultrastructural features in ex vivo human capsulotomy specimens generally show eversion of the capsulotomy edge, but in some cases, this was accompanied by areas of irregular capsule margin with frayed edges, likely caused by dissipated thermal energy. The postoperative appearance and SEM features warrant further assessment of the PPC integrity and clinical correlation.

Femtosecond laser-assisted versus phacoemulsification for cataract extraction and intraocular lens implantation: clinical outcomes review.

PURPOSE OF REVIEW: Femtosecond laser-assisted cataract surgery (FLACS) has gained popularity in recent years with the new technology suggesting potential improvements in clinical and safety outcomes over conventional phacoemulsification cataract surgery (PCS). A decade since the advent of FLACS has given time and experience for laser technology to develop in maturity, and better quality evidence to become available. This review evaluates current evidence on the clinical and safety outcomes for FLACS in comparison to PCS. RECENT FINDINGS: FLACS technology continues to improve and with it our confidence in tackling more complex patient indications. Concurrently other new technologies such as precision pulse capsulotomy also look to deliver the biomechanically ideal 5.2 mm capsulotomy, particularly as there remain suggestions from large studies and meta-analyses of raised capsular complications with FLACS compared with PCS and IOL technology responding to advantages of a consistent capsulotomy. Visual benefits of FLACS over and above PCS also remain to be conclusively demonstrated, with equivalence but not superiority. Economic modelling continues to indicate that FLACS remains 'not' cost-effective. SUMMARY: FLACS can be considered non-inferior to conventional PCS in term of safety and clinical outcomes. However, FLACS has yet to demonstrate an overall cost-benefit to the patient.

A Comparative Cohort Study of Visual Outcomes in Femtosecond Laser-Assisted versus Phacoemulsification Cataract Surgery.

PURPOSE: To evaluate visual outcomes after femtosecond laser-assisted cataract surgery (LCS) with phacoemulsification cataract surgery (PCS). DESIGN: Prospective, multicenter, comparative case series. PARTICIPANTS: Consecutive patients undergoing femtosecond LCS or PCS with intraocular lens insertion. METHODS: A total of 1876 eyes of 1238 patients (422 male and 772 female) who underwent cataract surgery between January 2012 and June 2014 were included in the study: 1017 eyes from center A and 859 eyes from center B. Cases underwent clinico-socioeconomic selection. Patients with absolute LCS contraindications were assigned to PCS; otherwise, all patients were offered LCS and elected on the basis of their decision to pay (the out-of-pocket cost for LCS). Demographic and postoperative data were collected to determine differences between groups. MAIN OUTCOME MEASURES: Six-month postoperative visual and refractive outcomes. Masked subjective refractions were performed 2 to 6 months postoperatively. RESULTS: There were 988 eyes in the LCS group and 888 eyes in the PCS group. Baseline best-corrected visual acuity (BCVA) was better in LCS compared with PCS (20/44.0 vs. 20/51.5; P < 0.0003). Preoperative surgical refractive aim differed significantly between groups (LCS -0.28 vs. PCS -0.23; P < 0.0001). More patients who received LCS had Toric lenses implanted compared with PCS (47.4% vs. 34.8%; P < 0.0001). Postoperative BCVA was better after LCS (20/24.5 vs. 20/26.4; P = 0.0003) with a greater proportion of LCS cases achieving BCVA >20/30 (LCS 89.7% vs. PCS 84.2%; P = 0.0006) and 20/40 (LCS 96.6% vs. PCS 93.9%; P = 0.0077). However, PCS cases had more letters gained compared with LCS cases (13.5 vs. 12.5 letters; P = 0.0088), reflecting baseline BCVA differences. Mean absolute error was higher in LCS compared with PCS (0.41 diopters [D] vs. 0.35 D; P < 0.0011). The percentage of eyes within 0.5 D of error from preoperative aim refraction was higher in the PCS group (LCS 72.2% vs. PCS 82.6%; P < 0.0001). CONCLUSIONS: Femtosecond LCS did not demonstrate clinically meaningful improvements in visual outcomes over conventional PCS.

Cost-effectiveness of femtosecond laser-assisted cataract surgery versus phacoemulsification cataract surgery.

PURPOSE: To perform a comparative cost-effectiveness analysis (CEA) of femtosecond laser-assisted cataract surgery (LCS) and conventional phacoemulsification cataract surgery (PCS) DESIGN: Retrospective CEA using computer-based econometric modeling. PARTICIPANTS: Hypothetical cohort of patients undergoing cataract surgery in the better eye based on a review of the current literature and our direct experience using LCS. METHODS: A cost-effectiveness decision tree model was constructed to analyze the cost-effectiveness of LCS compared with PCS. Complication rates of cataract surgery were obtained from a review of the current literature to complete the cohort of patients and outcomes. This data was incorporated with time trade-off utility values converted from visual acuity outcomes. MAIN OUTCOME MEASURES: Improvements in best-corrected visual acuity obtained from the literature were used to calculate the increase in quality-adjusted life-years (QALYs) in a hypothetical cohort between 6 months and 1 year after cataract surgery. This was combined with approximate costs in a cost-utility analysis model to determine the incremental cost-effectiveness ratios (ICERs). RESULTS: Based on the simulated complication rates of PCS and LCS and assuming resultant visual acuity outcome improvement of 5% in uncomplicated cases of LCS, the cost-effectiveness (dollars spent per QALY) gained from LCS was not cost-effective at $92 862 Australian Dollars. The total QALY gain for LCS over PCS was 0.06 units. Multivariate sensitivity analyses revealed that LCS would need to significantly improve visual outcomes and complications rates over PCS, along with a reduction in cost to patient, to improve cost effectiveness. Modeling a best-case scenario of LCS with excellent visual outcomes (100%), a significant reduction in complications (0%) and a significantly reduced cost to patient (of $300) resulted in an ICER of $20 000. CONCLUSIONS: Laser cataract surgery, irrespective of potential improvements in visual acuity outcomes and complication rates, is not cost effective at its current cost to patient when compared with cost-effectiveness benchmarks and other medical interventions, including PCS. A significant reduction in the cost to patient (via reduced consumable/click cost) would increase the likelihood of LCS being considered cost effective.

Anterior capsulotomy integrity after femtosecond laser-assisted cataract surgery.

OBJECTIVE: To compare the incidence of anterior capsular tears after femtosecond laser-assisted cataract surgery (FLACS) versus phacoemulsification cataract surgery (PCS) and to assess the ultrastructural features of anterior capsulotomy specimens (FLACS and PCS) using electron microscopy. DESIGN: Prospective, multicenter, comparative cohort case series. PARTICIPANTS: Consecutive patients undergoing FLACS or PCS. METHODS: A prospective cohort study of all patients (n = 1626) undergoing FLACS or PCS by 2 surgeons from centers A and B was undertaken to compare the incidence of anterior capsule tears. Anterior lens capsules were collected by 4 surgeons from centers A, B, C, and D using 3 different commercially available femtosecond platforms, each with latest version upgrades. Lens capsule tissue was prepared for scanning electron microscopy (SEM) using a total of 10 samples for patients undergoing PCS, and 40 samples for patients undergoing FLACS. MAIN OUTCOME MEASURES: Incidence of anterior capsule tear and comparative ultrastructural features of capsular samples from both PCS and FLACS cases. RESULTS: There was a significantly increased rate of anterior capsule tears in the FLACS group (15/804 [1.87%]) when compared with the PCS group (1/822 [0.12%]; P = 0.0002, Fisher exact test). In 7 cases, the anterior capsule tear extended to the posterior capsule. Because all cases had occurred in complete capsulotomy, the integrity of the anterior capsule was questioned in the FLACS group. Subsequent SEM sampling showed irregularity at the capsule margin, as well as multiple apparently misplaced laser pits in normal parts of the tissue. Aberrant pits were approximately 2 to 4 µm apart and occurred at a range of 10 to 100 µm radially from the capsule edge. CONCLUSIONS: Laser anterior capsulotomy integrity seems to be compromised by postage-stamp perforations and additional aberrant pulses, possibly because of fixational eye movements. This can lead to an increased rate of anterior capsule tears, and extra care should be taken during surgery after femtosecond laser pretreatment has been performed. A learning curve may account for some of the increased complication rate with FLACS. However, the SEM features raise safety concerns for capsular integrity after FLACS and warrant further investigation.

The use of heterochromatic flicker photometry to determine macular pigment optical density in a healthy Australian population.

PURPOSE: To establish the normal macular pigment density (MPOD) in a healthy adult Australian sample using heterochromatic flicker photometry (HFP). METHODS: Macular pigment density was measured using heterochromatic flicker photometry in a total of 201 subjects ranging in age from 21 to 84 years with healthy macula. Fifty-seven of the healthy subjects also completed a food-frequency dietary questionnaire. Best-corrected visual acuity (BCVA) was measured using logMAR, chart and macular morphological profiles were assessed using high-resolution integrated Fourier-domain optical coherence tomography (OCT). RESULTS: The average MPOD value was 0.41 ± 0.20 (range 0.07-0.79). There was no statistically significant difference between values in the left and right eye, with good interocular agreement (0.41 vs 0.40, r = 0.893, p < 0.01). Age significantly predicted MPOD score (R (2) = 0.07, p < 0.05). A subgroup analysis of patients who completed the dietary questionnaire revealed a close correlation between higher diet scores and higher MPOD (r = 0.720 p = 0.031). There was no effect of smoking, gender, or iris colour on MPOD values. There was no significant correlation between BCVA, macular OCT profiles, and MPOD. CONCLUSION: Given that MPOD values are potentially affected by geographical variation, we have determined a mean MPOD value for healthy subjects in a population south of the equator, providing a reference point for future studies on Caucasian samples.

Bilateral maculopathy associated with sertraline.

OBJECTIVE: We report a rare case of bilateral maculopathy that developed with the initiation of sertraline. METHODS: We conducted a case report and review of the literature. RESULTS: A 23-year-old man rapidly developed maculopathy with associated visual blurring after the initiation of sertraline. Treatment was ceased with the patient subsequently reporting mild improvement in visual symptoms. CONCLUSIONS: Maculopathy associated with sertraline use has yet to be established and recognized as an adverse side effect. With only one previous reported case in the literature, this condition requires further awareness.

Corneal amyloid staining after trypan blue in Descemet's membrane endothelial keratoplasty.

Purpose: This case report seeks to highlight impressive photographs of amyloid staining with trypan blue that persisted after DMEK surgery with 3 years follow-up. This has only been reported in the literature twice previously, and may have contributed to visual symptoms in the early post-operative period of this patient. Observations: We report a case of an 82-year-old patient with concurrent Fuchs' corneal endothelial dystrophy and lattice corneal dystrophy who suffered permanent trypan blue staining of the amyloid deposits after descemet's membrane endothelial keratoplasty (DMEK) surgery. Conclusions and importance: Trypan blue staining of amyloid deposits in the corneal stroma is permanent, with research suggesting potential stimulation of progression or recurrence of amlyoid deposition. This is relevant for all anterior segment surgeons using trypan blue in the setting of primary (eg. lattice corneal dystrophy) or secondary amyloid deposition (eg. polymorphous amyloid degeneration, chronic inflammation, systemic disease). Trypan blue staining should be limited or alternative surgical options such as descemet's stripping automated endothelial keratoplasty (DSAEK) considered.

Toward zero effective phacoemulsification time using femtosecond laser pretreatment.

OBJECTIVE: To compare effective phacoemulsification time after femtosecond laser pretreatment with conventional phacoemulsification and the associated effect on visual outcomes and endothelial cell loss. DESIGN: Prospective, consecutive, single-surgeon case-control study. CONTROLS: Controls underwent phacoemulsification cataract extraction plus insertion of an intraocular lens (IOL). Cases underwent pretreatment with the femtosecond laser followed by phacoemulsification cataract extraction and IOL insertion. METHODS: Two hundred one eyes underwent cataract surgery between April 2012 and July 2012. Data collected included patient demographics, preoperative characteristics, femtosecond lens fragmentation method, effective phacoemulsification time (EPT), intraoperative complications, and postoperative outcomes. MAIN OUTCOME MEASURES: Effective phacoemulsification time, intraoperative complications, corneal endothelial cell loss, as well as postoperative best-corrected visual acuity, intraocular pressure, and refractive outcomes. RESULTS: Patient demographics were similar between groups. There was no difference between baseline cataract grades (2.59 ± 0.71 vs. 2.52 ± 0.72, not significant). One hundred percent of cases pretreated with the femtosecond laser had complete capsulotomy. Mean EPT was reduced by 83.6% in the femtosecond pretreatment group (P<0.0001) when compared with controls, with 30% having 0 EPT (P<0.0001). Effective phacoemulsification time was reduced 28.6% within the femtosecond group using improved lens fragmentation algorithms, and a further 72.8% reduction was achieved with a 20-gauge phacoemulsification tip. Overall, there was a 96.2% reduction in EPT between controls and the optimized femtosecond pretreatment group. This was associated with a 36.1% reduction in endothelial cell loss in the femtosecond group. Visual and refractive outcomes were similar to those of conventional cataract surgery. CONCLUSIONS: Femtosecond laser pretreatment results in a significant reduction in effective phacoemulsification time, including the possibility of 0 EPT. Further reductions may be achieved using optimization of lens fragmentation patterns and surgical technique. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Femtosecond laser-assisted cataract surgery compared with conventional cataract surgery.

BACKGROUND: To investigate the safety and efficacy of the Catalys (Optimedica, Santa Clara, CA, USA) femtosecond laser-assisted cataract surgery system compared with conventional phacoemulsification cataract extraction. DESIGN: Prospective, consecutive, parallel cohort study. PARTICIPANTS: The first 200 eyes undergoing conventional cataract surgery to the first 200 eyes undergoing femtosecond laser-assisted cataract surgery between April and July 2012. METHODS: Femtosecond laser-assisted cataract surgery involved anterior capsulotomy and lens fragmentation based on optical coherence tomography-guided treatment mapping. Conventional cataract surgery involved manual continuous curvilinear capsulorhexis. Both procedures were completed by standard phacoemulsification and insertion of an intraocular lens. MAIN OUTCOME MEASURES: Effective phacoemulsification time and intraoperative complication rates. RESULTS: Patient demographics were similar between both groups. There was no statistically significant difference in intraoperative complications between femtosecond laser-assisted cataract surgery and conventional surgery. There was one posterior capsule rupture in both groups (0.5%; not significant). One hundred per cent of cases treated with the femtosecond laser had a complete capsulotomy. Vacuum time decreased with experience. Effective phacoemulsification time was reduced by 70% in the femtosecond group (P < 0.0001). Twenty-six cases in the femtosecond group versus one case in the conventional group had 0 effective phacoemulsification time (P < 0.0001). CONCLUSION: Femtosecond laser-assisted cataract surgery appears to be as safe as conventional cataract surgery in the short term and results in significantly lower effective phacoemulsification time. Although it may allow for greater efficiency and decreased postoperative complications, further research is needed into long-term safety aspects such as corneal endothelial cell loss.

Comparative Evaluation Of Clinical Characteristics And Visual Outcomes Of Traumatic And Non-Traumatic Graft Dehiscence Following Corneal Transplantation Surgery.

PURPOSE: To compare patient demographics, clinical associations and visual outcomes between traumatic and non-traumatic wound dehiscence, following corneal transplantation. METHODS: Retrospective review of all patients presenting with post-keratoplasty wound dehiscence to the Royal Victorian Eye and Ear Hospital between January 2005 and December 2017. Patients with wound dehiscence following keratoplasty of any cause were included. RESULTS: Of 71 eyes from 71 patients included, 60 (85%) were penetrating keratoplasty patients. The mean age was 56.4 years (SD=22.7, range 17.6-97) and 62% (n = 44) of patients were male. There were 28 (39%) cases of traumatic dehiscence and 43 (61%) cases of non-traumatic dehiscence. The median time interval from keratoplasty to dehiscence was significantly less in non-traumatic patients than traumatic patients (0.2 years, IQR 0.1-2.0 vs 2.3 years, IQR 0.3-14.8, p=0.01). There was no significant difference in best-corrected visual acuity at 6 months between traumatic and non-traumatic dehiscence (6/60 vs 6/36, p=0.62), suture technique (continuous vs interrupted, p=0.12), or graft type (penetrating keratoplasty vs deep anterior lamellar keratoplasty) after adjusting for keratoconus (p=0.41). CONCLUSION: Post-keratoplasty wound dehiscence is a serious complication and can cause significant loss of vision. While the risk of dehiscence is lifelong, the first 3 years post-keratoplasty carry the highest risk, with non-traumatic dehiscence tending to occur earlier than traumatic dehiscence.

Techniques of anterior capsulotomy in cataract surgery.

Optimal outcomes of a cataract surgery largely depend on the successful performance of an anterior capsulotomy. It is one of the most important steps of modern cataract surgery which reduces the risk of capsular tears and ensures postoperative stable intraocular lens (IOL). Anterior capsulotomy is considered ideal if it is round, continuous, well-centered, and overlaps the implanted IOL around its circumference. If any of these features is missing, it can be a cause of impedance for desired surgical and visual outcomes. Manual can opener and manual capsulorhexis are the routine standard techniques employed for manual extracapsular cataract extraction and phacoemulsification, respectively. Recent increasing use of femtosecond laser cataract surgery has allowed cataract surgeons to obviate inherent inaccuracies of manual anterior capsulotomy techniques. There is an ongoing quest to find an ideal, risk free, and surgeon-friendly technique of anterior capsulotomy that can be employed for surgery in all types of cataracts.

Intraoperative performance and ultrastructural integrity of human capsulotomies created by the improved precision pulse capsulotomy device.

PURPOSE: To investigate the intraoperative performance and the ultrastructural features of anterior capsulotomy performed with the improved Zepto precision pulse capsulotomy (PPC) device. SETTING: Launceston Eye Institute, Launceston, Tasmania, Australia. DESIGN: Prospective, consecutive case series. METHODS: Intraoperative observation of performance and complications were made on consecutive eyes having capsulotomies with the improved PPC device. The capsulotomy specimens were examined under scanning electron microscope and compared with manual continuous curvilinear capsulorhexis and femtosecond laser-assisted cataract surgery specimens. RESULTS: The study comprised 52 eyes. Intended capsulotomy occurred in 50 eyes with 2 device failures. Complete free-floating capsulotomies were achieved in 48 eyes (96%). Anterior capsule tears occurred in 2 eyes (4%). CONCLUSIONS: The ability of the PPC device to create complete free-floating capsulotomies improved; however, the radial tear rate remained high. The ultrastructural features in ex vivo human capsulotomy specimens still showed areas of irregular capsule margin with frayed edges.

Thermal capsulotomy: Initial clinical experience, intraoperative performance, safety, and early postoperative outcomes of precision pulse capsulotomy technology.

PURPOSE: To assess the clinical safety and performance of a new thermal capsulotomy device in patients having cataract surgery. SETTING: Launceston Eye Institute, Launceston, Tasmania, Australia. DESIGN: Prospective case series. METHODS: This single-surgeon consecutive series comprised eyes having capsulotomy with a precision pulse capsulotomy (PPC) device (Zepto). Baseline demographic information and preoperative, intraoperative, and early postoperative outcomes, including complications, intraocular pressure (IOP), flare photometry, corneal and retinal thickness, and specular microscopy were collected and analyzed. Outcomes included PPC performance, intraoperative complications, effective phacoemulsification time, IOP, postoperative inflammation, corneal edema, endothelial cell density, functional evaluation of the corneal endothelium, retinal thickness, cost-effectiveness, and early postoperative visual acuity. RESULTS: The study evaluated 100 eyes. Complete free-floating capsulotomy was achieved in 70 eyes (72%). Focal attachments were identified in 17 eyes (18%) and broad attachments in 10 eyes (10%). Intended PPC capsulotomy failed in 3 eyes due to operator or device error. Anterior capsule tears occurred in 4 eyes (4%); otherwise, there were no significant safety signals in the early postoperative period. There was no evidence of a learning curve effect; however, use of a dispersive ophthalmic viscosurgical device (OVD) is postulated as influencing capsulotomy completeness. CONCLUSIONS: The PPC device created round, reproducible, appropriately sized capsulotomies in 72% of eyes. The incidence of incomplete capsulotomy and radial tear rate was high and was possibly associated with the use of a dispersive OVD.

Cystoid macular edema after femtosecond laser-assisted versus phacoemulsification cataract surgery.

PURPOSE: To evaluate the incidence of postoperative clinical cystoid macular edema (CME) associated with femtosecond laser-assisted cataract surgery (Catalys laser system) versus phacoemulsification cataract surgery. SETTING: Launceston Eye Institute, Launceston, Tasmania, Australia. DESIGN: Nonrandomized, single-surgeon, prospective, comparative cohort case series. METHODS: Patients who had femtosecond laser-assisted cataract surgery and phacoemulsification cataract surgery between March 2012 and July 2014 were included in the study. The femtosecond laser-assisted cataract surgery group had anterior capsulotomy, lens fragmentation, with or without corneal incisions via femtosecond laser pretreatment. Standard phacoemulsification surgery and foldable acrylic intraocular lens insertion proceeded in all cases. All patients received topical nonsteroidal drops commencing 2 days preoperatively and continuing for 4 weeks postoperatively. The incidence of postoperative clinical CME (confirmed by optical coherence tomography) and comparison between groups were measured. The main outcome measure was the clinical CME rates. RESULTS: Of the eyes, 833 had femtosecond laser-assisted cataract surgery amd 458 had standard phacoemulsification cataract surgery. Both groups had similar baseline parameters. There were 7 cases of postoperative CME (0.8%) in the femtosecond laser-assisted cataract surgery group compared to 1 case (0.2%) in the phacoemulsification cataract surgery group, highlighting a trend toward greater cystoid macular edema in the femtosecond laser-assisted cataract surgery group. This correlated with a change in laser treatment speed (due to a software upgrade), suggesting that retinal safety thresholds need further careful analysis. CONCLUSION: Increased CME might be a subthreshold retinal injury safety signal after femtosecond laser pretreatment and warrants further study. FINANCIAL DISCLOSURE: There are no financial or conflicts of interest for any author.