Predictors of intraocular pressure reduction after femtosecond laser-assisted cataract surgery versus conventional phacoemulsification surgery: a prospective trial.

PURPOSE: To evaluate the association between postoperative intraocular pressure (IOP) reduction and phacoemulsification parameters in patients who underwent both conventional phacoemulsification surgery (CPS) and femtosecond laser-assisted cataract surgery (FLACS). METHODS: This was a prospective multicenter comparative study that enrolled 90 participants who underwent cataract surgery at the University of Maryland Medical System and the Wilmer Eye Institute. Patients underwent FLACS in one eye and CPS in the fellow eye. IOP was measured prior to surgery and monitored through six months postoperatively. Demographic, clinical, biometric, and intraoperative variables including cumulative dissipated energy (CDE), aspiration time, and phacoemulsification time were analyzed for any significant association with postoperative IOP. Postoperative IOP reduction was the primary outcome variable. A secondary goal of the study was to determine differences in postoperative IOP reduction between CPS and FLACS cohorts. RESULTS: In total, 157 non-glaucomatous eyes were included. Using multivariable analysis, we found preoperative IOP to be consistently associated with postoperative IOP reduction in the entire cohort. At the 6-month follow-up visit, there was a 12.4% reduction in IOP (-2.2 ± 3.4 mm Hg) seen, with no statistically significant difference between FLACS and CPS (12.3% ± 19.4% vs 12.5% ± 19.3%, respectively, p = 0.32). FLACS reduced the CDE required for phacoemulsification (6.6 ± 4.4%-seconds vs 8.6 ± 6.9%-seconds, respectively, p < 0.05). CDE was a predictor of IOP response at 6 months, but subgroup analysis revealed that this trend was driven by seven eyes requiring high CDE, and for the majority of eyes, CDE did not influence the size of the decrease. The seven eyes experiencing highest CDE were less likely to show IOP reduction at 6 months. CONCLUSION: Both FLACS and CPS resulted in similar and significant IOP reductions through 6 months after surgery. Preoperative IOP was significantly associated with IOP reduction, and CDE generally did not influence the size of the decrease.

Corneal Structural Changes in Congenital Glaucoma.

OBJECTIVE: To identify corneal structure differences on quantitative high-frequency ultrasound biomicroscopy (UBM) among subjects with congenital glaucoma compared with controls. METHODS: This prospective case-control study evaluated 180 UBM images from 44 eyes of 30 subjects (18 control and 12 glaucoma, mean age 5.2±8.0 years, range 0.2-25.8 years) enrolled in the Pediatric Anterior Segment Imaging and Innovation Study (PASIIS). ImageJ was used to quantify a comprehensive set of corneal structures according to 21 quantitative parameters. Statistical analysis compared corneal measurements in glaucoma subtypes and age-matched controls with significance testing and mixed effects models. RESULTS: Significant differences between congenital glaucoma cases and controls were identified in 16 of 21 measured parameters including angle-to-angle, central and peripheral corneal thicknesses, scleral integrated pixel density, anterior corneal radius of curvature, and posterior corneal radius of curvature. Eight parameters differed significantly between primary congenital glaucoma and glaucoma following congenital cataract surgery. CONCLUSION: Multiple measurable corneal structural differences exist between congenital glaucoma and control eyes, and between primary and secondary congenital glaucoma, including but not limited to corneal width and thickness. The structural differences can be quantified from UBM image analysis. Further studies are needed to determine whether corneal features associated with glaucoma can be used to diagnose or monitor progression of congenital glaucoma.

Comparison of cumulative dispersed energy (CDE) in femtosecond laser-assisted cataract surgery (FLACS) and conventional phacoemulsification.

PURPOSE: To compare the amount of phacoemulsification ultrasound energy used between eyes undergoing femtosecond laser-assisted cataract surgery (FLACS) and conventional phacoemulsification. METHODS: One eye of consecutive patients undergoing routine non-complicated phacoemulsification from January 2014 to December of 2015 was included in the analysis. FLACS was performed using the Alcon LenSx. Linear regression was used for analysis with type of surgery (FLACS versus conventional phacoemulsification) as the exposure and cumulative dispersed energy (CDE) as the outcome variable. Age, surgeon, eye side, and eye sequence (first versus second eye) were covariates. RESULTS: A total of 1159 surgeries met inclusion criteria. The average age of the cohort was 70.6 (SD 8.6) years, 590 cases (51%) were performed by surgeon 1, and 582 cases (50%) were right eyes. Overall, FLACS resulted in significantly lower CDE as compared to conventional phacoemulsification (ß = 0.89, 95% CI 0.83, 0.95). When stratified by eye side and surgeon, FLACS performed on left eyes operated on by surgeon 1 resulted in lower CDE as compared to conventional phacoemulsification (ß = 0.76, 95% CI 0.66, 0.87), but not for right eyes operated on by surgeon 1 (ß = 0.92, 95% CI 0.79, 1.07) or for eyes operated on by surgeons 2 or 3. CONCLUSIONS: The use of FLACS on the Alcon LenSx platform results in a small decrease in phacoemulsification energy as compared to conventional phacoemulsification in certain cases. Further study assessing optimal laser settings and surgical technique is necessary.

Cataract surgery and environmental sustainability: Waste and lifecycle assessment of phacoemulsification at a private healthcare facility.

PURPOSE: To measure the waste generation and lifecycle environmental emissions from cataract surgery via phacoemulsification in a recognized resource-efficient setting. SETTING: Two tertiary care centers of the Aravind Eye Care System in southern India. DESIGN: Observational case series. METHODS: Manual waste audits, purchasing data, and interviews with Aravind staff were used in a hybrid environmental lifecycle assessment framework to quantify the environmental emissions associated with cataract surgery. Kilograms of solid waste generated and midpoint emissions in a variety of impact categories (eg, kilograms of carbon dioxide equivalents). RESULTS: Aravind generates 250 grams of waste per phacoemulsification and nearly 6 kilograms of carbon dioxide-equivalents in greenhouse gases. This is approximately 5% of the United Kingdom's phaco carbon footprint with comparable outcomes. A majority of Aravind's lifecycle environmental emissions occur in the sterilization process of reusable instruments because their surgical system uses largely reusable instruments and materials. Electricity use in the operating room and the Central Sterile Services Department (CSSD) accounts for 10% to 25% of most environmental emissions. CONCLUSIONS: Surgical systems in most developed countries and, in particular their use of materials, are unsustainable. Results show that ophthalmologists and other medical specialists can reduce material use and emissions in medical procedures using the system described here.

Microinvasive Glaucoma Surgery: An Evidence-Based Assessment.

INTRODUCTION: The advent of Microinvasive Glaucoma Surgery (MIGS) offers a novel approach in the treatment of glaucoma with the number of procedures developing at an exciting pace. AREAS COVERED: MIGS procedures aim to lower intraocular pressure (IOP) via four mechanisms: (1) increasing trabecular outflow, (2) increasing outflow via suprachoroidal shunts, (3) reducing aqueous production, and (4) subconjunctival filtration. A comprehensive search for published studies for each Microinvasive Glaucoma Surgery (MIGS) device or procedure was undertaken using the electronic database PubMed. Search terms included 'minimally invasive glaucoma surgery', 'microincisional glaucoma surgery', and 'microinvasive glaucoma surgery'. A manual search for each device or procedure was also performed. After review, randomized control trials and prospective studies were preferentially included. EXPERT OPINION: These procedures offer several benefits: an improved safety profile allowing for intervention in earlier stages of glaucoma, combination with cataract surgery, and decreased dependence on patient compliance with topical agents. Established MIGS procedures have proven efficacy and more recent devices and procedures show promising results. Despite this, further study is needed to assess the long term IOP-lowering effectiveness of these procedures. Particularly, rigorous study with more randomized control trials and head-to-head comparisons would allow for better informed clinical and surgical decision-making. MIGS offers new solutions for glaucoma treatment.

Effect of intraoperative factors on IOP reduction after phacoemulsification.

The purpose of the study was to determine the independent predictors of long-term intraocular pressure (IOP) reduction after cataract surgery with phacoemulsification. This is a retrospective review of uncomplicated cataract surgeries from 2006 to 2008 at the Baltimore VA Medical Center with longitudinal follow-up. Demographic, clinical, biometric, and intraoperative variables including phacoemulsification parameters were recorded. Univariate and multivariate linear regression were used to analyze the relationship between these variables and postoperative IOP, which was the outcome variable. Analysis was performed in 115 eyes of 115 patients who underwent uncomplicated phacoemulsification during the study period. There was an average postoperative IOP reduction through 12, 24, and 36 months of -1.7 ± 3.1, -1.5 ± 3.8, and -1.3 ± 2.6 mmHg, respectively. Higher preoperative IOP (P < 0.001), a more anterior relative lens position (P < 0.05), and longer phaco time (P < 0.05) were significantly associated with greater postoperative decrease in IOP using univariate analysis. Using multivariate analysis, preoperative IOP (P < 0.001), and phaco time (P = 0.038) were associated with greater postoperative IOP reduction through 24 months. Phaco time is independently associated with IOP reduction after adjusting for age and preoperative IOP. Higher preoperative IOP is associated with a greater IOP-lowering effect after phacoemulsification.

Unilateral Glaucoma Associated with Conjunctival Angioma and Choroidal Thickening without Facial Angioma.

We report a case of a suspected Sturge-Weber syndrome variant diagnosed at the age of 58 with the help of enhanced depth imaging spectral-domain ocular coherence tomography (EDI-SDOCT). A 58-year-old female with unilateral glaucoma was suspected to have choroidal vascular lesion, conjunctival angioma, and no facial port-wine stain who presented to the clinic with bleb dysesthesia many years after trabeculectomy. EDI-SDOCT was performed and revealed markedly increased choroidal thickness in the affected eye. EDI-SDOCT may be helpful in diagnosing Sturge-Weber variants without facial involvement and may aid in the investigation of the pathogenesis of this disease.

Risk factors for adverse consequences of low intraocular pressure after trabeculectomy.

PURPOSE: To determine the risk factors for low intraocular pressure (IOP) and its detrimental consequences after trabeculectomy. PATIENTS AND METHODS: We performed a retrospective chart review of consecutive patients aged 12 years and above undergoing trabeculectomy alone by 1 of 2 surgeons between May 2000 and October 2008 at the Wilmer Institute. RESULTS: Among 753 eyes of 596 patients, 112 eyes (14.9%) of 103 patients had an IOP of ≤5 mm Hg at ≥3 months postoperatively (late low IOP). Physical signs related to low IOP occurred in 61 eyes of 58 patients, and 40 eyes of 37 patients had revision surgery for low IOP. Physical signs of low IOP included 34 eyes with choroidal detachment or shallow anterior chamber, 10 with hypotony maculopathy, and 7 with both. Compared with 187 control eyes of 165 patients, risk factors for late low IOP included: surgeon 2 (P=0.0003), left eyes (P=0.03), and secondary glaucoma (P=0.05). Physical signs of low IOP were more common in phakic eyes (P=0.03), whereas need for revision surgery was associated with younger age (P=0.01). The presence of hypotony maculopathy significantly decreased the risk of choroidal detachment/shallow anterior chamber (P=0.003). Hypotony maculopathy was associated with younger age (P=0.02). CONCLUSIONS: Late low IOP was more common with techniques used by 1 of 2 surgeons and in eyes with secondary glaucoma. Clinical signs of low IOP were more common in phakic eyes. Younger age was a risk factor for hypotony maculopathy. Hypotony maculopathy and choroidal detachment tend to occur in different eyes.

Exophiala jeanselmei keratitis: case report and review of literature.

PURPOSE: To describe a patient with Exophiala jeanselmei keratitis and to review the prior cases reported in the literature. METHODS: We report one patient with keratitis after remote injury and chronic steroid use and review the six prior reported cases. RESULTS: Culture plates from corneal scraping revealed growth of the dematiaceous fungi, E. jeanselmei, a rare causative organism of ocular infection. The patient underwent therapy with topical and intracameral antifungals and subsequently required a corneal transplant. Biopsy of the donor graft confirmed the diagnosis of E. jeanselmei. This is the first reported case to use intracameral antifungal agents and the first biopsy proven case. Half of reported cases experienced associated trauma, and severity was generally related to delay in diagnosis. CONCLUSIONS: Trauma and chronic topical steroid use contributed to the development of severe keratitis in this patient. Patients on chronic steroids should be monitored closely. Topical, subconjunctival, and intracameral antifungals have all been effective in treating this pathogen. If diagnosed and treated early, E. jeanselmei keratitis can have a good visual outcome.