Materials in the vitreous during cataract surgery: nature and incidence, with two cases of histological confirmation.

BACKGROUND: To identify and classify materials in the vitreous observed during phacoemulsification cataract surgery (phaco). DESIGN: Prospective, consecutive, observational case series at one ophthalmic day surgery in Sydney, Australia. PARTICIPANTS: A total of 767 consecutive phaco cases. Cases were excluded if there was posterior capsule rupture or vitreous loss intraoperatively. METHODS: For each patient, age, gender, baseline corrected distance visual acuity, presence of pseudoexfoliation, nuclear sclerosis grade and phacoemulsification ultrasound time were recorded. The relationship between these variables and materials in the vitreous was evaluated with regression analysis. Two patients with materials in the vitreous developed an acute intraoperative rock-hard eye syndrome. In these two patients, pars plana needle aspiration of retrolenticular fluid was performed to re-establish normal intraocular pressure. Histology was undertaken to compare this fluid with known lens material retrieved from the Fluid Management System bags in two unrelated cases. MAIN OUTCOME MEASUREMENTS: Presence of materials in the vitreous during phaco. RESULTS: Materials in the vitreous were observed in either Berger's space or the anterior vitreous in 386 eyes (50.3% of cases); the majority was putatively lens material (46.5% of all cases). Pigment and ophthalmic viscoelastic device were seen in the anterior vitreous in 9.8% and 1.7% of cases, respectively. Logistic regression analysis demonstrated that higher nuclear sclerosis grade (P = 0.025), male gender (P = 0.003) and greater age (P = 0.016) were predictive of the presence of materials in the vitreous. Histological assessment with light microscopy and birefringence techniques identified the materials in the vitreous as lens material. CONCLUSION: Materials in the vitreous were seen in 50.3% of phaco cases. It has been histologically demonstrated that lens materials can be introduced into the anterior vitreous during phaco.

Stability of the acrysof toric intraocular lens in combined cataract surgery and transconjunctival sutureless vitrectomy.

PURPOSE: To report the outcomes of combined cataract surgery with toric intraocular lens (IOL) implantation when performed in conjunction with transconjunctival sutureless pars plana vitrectomy. DESIGN: Retrospective interventional case series. PARTICIPANTS: Consecutive series of 55 eyes of 51 patients from April 2007 to December of 2010. METHODS: All eyes underwent combined simultaneous small incision cataract surgery, toric IOL implantation, and transconjunctival sutureless vitrectomy surgery. MAIN OUTCOME MEASURES: Postoperative visual acuity, postoperative astigmatism, and rotational stability of the IOL. RESULTS: Preoperative best-corrected visual acuity was 0.32 ± 0.15 logMar (Snellen 20/43) and improved to 0.16 ± 0.10 (Snellen 20/29) postoperatively uncorrected (P < 0.01) and to 0.08 ± 0.11 best-corrected (Snellen 20/24) (P < 0.01). Preoperative astigmatism was 1.75 ± 1.0 diopters (D) (range, 0-4.75 D) and improved to 0.5 ± 0.50 D (range, 0-2.5 D) postoperatively (P < 0.01). Final measured postoperative IOL axis deviation from target axis was 4 ± 6° (range, 0-32). Final IOL axis was within 5° of target in 47 (85%) eyes, within 10 degrees of target in 51 (93%) eyes, and was within 15° of target in 52 (95%) eyes. CONCLUSION: Toric lens position and axis remained stable after implantation during combined cataract surgery and transconjunctival sutureless vitrectomy.

Optimizing precision in toric lens selection by combining keratometry techniques.

PURPOSE: To increase precision in toric intraocular lens selection by reducing the frequency of outliers that arise from technology-dependent variability during the preoperative assessment for routine cataract surgery. METHODS: Mean preoperative values for absolute sphere, amount of astigmatism, and steepest cylindrical axis were obtained for 87 eyes (54 patients) each with a manual keratometer and four automated keratometers. The mean sphere, amount of astigmatism, and steepest cylindrical axis across five technologies for each eye were defined as the meld sphere, meld astigmatism, and meld axis, respectively. Each technology was evaluated against the meld by Bland­Altman analysis, Student's paired t test, and correlation coefficients. Further comparison between individual technologies and the meld quantified the number of outlier measurements each technology produced. RESULTS: The number of outliers between individual keratometers and the meld differed with specific measurement of sphere, axis, or amount of astigmatism. Although statistical analysis using Bland­Altman plots, correlation coefficients, and paired t tests suggested insignificant difference from meld measurements for each parameter, precision-guided analysis presented more clinically significant outliers. The number of outliers can be reduced for sphere (range: 2%-46% to 1%-6%), astigmatism (range: 6%-23% to 0%-2%), and axis outliers (range: 15%-27% to 3%-6%) by averaging measurements from automated and manual keratometers. CONCLUSIONS: Although multiple keratometry technologies produced similar, average measurements, the authors found a disturbing number of outliers that may be overlooked when employing a single technology. Measurement errors can be dramatically reduced by averaging measurements from manual keratometry with any automated technology to make toric lens selection more precise.

Prospective multicenter study of toric IOL outcomes when dual zone automated keratometry is used for astigmatism planning.

PURPOSE: To evaluate clinical outcomes when toric intraocular lens (IOL) calculations are based on the keratometric output from the Lenstar LS-900 dual zone automated keratometer (Haag-Streit AG, Koeniz, Switzerland). METHODS: Eligible subjects presenting for toric IOL implantation at five sites were measured with a dual-zone automated keratometer. The data were used to plan the power and angle of the toric IOL to be implanted. Refractive and visual acuity status were checked at 1 and 3 months postoperatively. RESULTS: A total of 102 eyes had relevant data for analysis. More than 76% of eyes had 0.50 diopter or less of refractive astigmatism at 1 and 3 months, with no difference by level of astigmatism corrected. More than half of the eyes had uncorrected distance visual acuity of 20/20 or better and 78% were 20/25 or better. A new measure of effectiveness of toric correction power is described that suggested lens selection was appropriate. Results appeared better than those obtained in previous studies when the IOL cylinder power and alignment were calculated using manual keratometry. CONCLUSIONS: In this series of eyes from multiple centers, the calculation of toric IOL power using dual-zone automated keratometry measurements produced clinical results that were better than results in the literature where manual keratometry was used.

Purifying air over the operating field with a new mobile laminar airflow device to reduce the possibility of airborne contamination.

PURPOSE: To investigate the effectiveness of a mobile laminar airflow (LAF) device designed to reduce both airborne particles and lint fibers within the sterile field during cataract surgery. SETTING: Cincinnati Eye Institute, Cincinnati, Ohio. DESIGN: Prospective case series. METHODS: The number of airborne particles sized 0.5 µm, 1.0 µm, and 1.5 µm were measured at different locations and times during 116 routine phacoemulsification procedures with and without the use of a mobile LAF device. In a companion study, the presence of lint fibers in 99 eyes undergoing cataract surgery with a mobile LAF device was compared with 50 eyes in the control group. Lint fibers were differentiated as either falling onto the ocular surface or being carried into the sterile field by an instrument. RESULTS: A statistically significant reduction (P < .0005) occurred in all 3 particle sizes measurements when the LAF device was used: 79.0% (93.6 ± 16.1 vs 445.3 ± 30.9), 81.7% (11.30 ± 1.98 vs 61.85 ± 5.34), and 90.8% (0.241 ± 0.056 vs 2.624 ± 0.362) in the 0.5 µm, 1.0 µm and 5.0 µm particles, respectively. Lint fibers were identified in 18% (9/50) of eyes in the control group and 16.16% (16/99) of eyes in the LAF group. Although the number of lint fibers carried into the sterile field was similar in each group, the incidence of lint fibers falling onto the sterile field was reduced from 6% (3/50) to 0% (0/99) when the LAF was used (P = .014). CONCLUSIONS: The mobile LAF device was highly effective in reducing the number of particulate matter and lint fibers within the sterile surgical field when used during cataract surgery.

Negative dysphotopsia: long-term study and possible explanation for transient symptoms.

PURPOSE: To study the incidence, course, and common factors of patients with negative dysphotopsia and consider the possible role of the corneal incision in cases in which symptoms are transient. SETTING: Private practice and the University of Cincinnati, College of Medicine, Cincinnati, Ohio, USA. METHODS: Phacoemulsification with implantation of a single-piece acrylic intraocular lens (IOL) was performed in 250 consecutive routine cataract procedures. Patients were asked whether they noticed a temporal shadow on the day after surgery and were followed by serial evaluations for 3 years. Evaluations included subjective questionnaires and objective testing. RESULTS: The incidence of negative dysphotopsia was 15.2% on the first postoperative day, decreasing to 3.2% after 1 year, then 2.4% after 2 and 3 years. Common findings included a shallow orbit, prominent globe, space greater than 0.45 mm between the iris and IOL by ultrasound biomicroscopy, and perimetric comet-shaped light in the area corresponding to the shadow. Slitlamp revealed a transparent peripheral capsule and a shadow sign in which a linear shadow on the iris became curvilinear as the light from the slit beam was projected through the incision toward the pupil. CONCLUSIONS: Two groups of patients experienced negative dysphotopsia that rapidly resolved or remained unchanged from the first postoperative day. It is hypothesized that the corneal edema associated with a beveled temporal incision contributes to transient negative dysphotopsia.

Evaluation of the relationship between corneal diameter and lens diameter.

PURPOSE: To investigate the relationship between corneal diameter (white to white) (WTW) and the dimensions of the crystalline lens. SETTING: Private practice, Cincinnati, Ohio, USA. METHODS: Human cadaver eyes were oriented to allow caliper measurements of the horizontal and vertical corneal diameters (WTW). Globes were sectioned and reoriented so the horizontal and vertical measurements of the crystalline lens were recorded and statistically analyzed. RESULTS: The mean horizontal corneal diameter was 11.46 mm, approximately 0.8 mm greater than the mean vertical corneal diameter of 10.63 mm. The mean horizontal crystalline lens diameter was 9.28 mm, nearly identical to the mean vertical diameter of 9.30 mm. The correlation between the mean corneal diameter and mean lens diameter was weak, although it was significant. There was no correlation between horizontal dimensions. CONCLUSION: It was not possible to predict the dimensions of the human crystalline lens using calipers to measure the WTW corneal diameter.

Evaluation of the safety of prophylactic intracameral moxifloxacin in cataract surgery.

PURPOSE: To evaluate posterior and anterior segment safety of an intracameral injection of moxifloxacin 0.5% ophthalmic solution as prophylaxis for endophthalmitis in patients having cataract surgery. SETTING: Three private practices, the University of Minnesota School of Medicine, Stillwater, Minnesota, and the University of Cincinnati, Cincinnati, Ohio, USA. METHODS: In this prospective randomized combined-center open-label trial, 57 eyes of 47 patients were treated with intracameral moxifloxacin (250 mug/0.050 mL) or an equal volume of balanced salt solution at the conclusion of cataract surgery with intraocular lens implantation. Safety parameters, including visual acuity, intraocular pressure, endothelial cell counts, corneal pachymetry, corneal clarity and edema, and anterior chamber cells and flare, were evaluated preoperatively and for 3 months postoperatively. RESULTS: Optical coherence tomography results showed no statistically significant differences between the 2 treatment groups preoperatively or at 3 months. There were also no statistically significant differences between the 2 treatment groups in all other parameters preoperatively or at 1 day, 2 to 4 weeks, or 3 months. No study-related adverse events occurred. CONCLUSION: There was no increased safety risk associated with a 250 mug/0.050 mL intracameral injection of moxifloxacin, which appears to be safe in the prophylaxis of endophthalmitis after cataract surgery.