Outcome of astigmatism correction using femtosecond laser combined with cataract surgery: penetrating vs intrastromal incisions.

PURPOSE: To compare the effectiveness of penetrating vs intrastromal femtosecond laser corneal relaxing incisions (CRIs) in reducing corneal astigmatism during cataract surgery. SETTINGS: Baylor College of Medicine and Mercy Clinic Eye Specialists. DESIGN: Prospective randomized study. METHODS: 248 eyes from 248 patients were included. Patients were randomly assigned to undergo paired penetrating (8 mm optical zone [OZ] at 1 center and 9 mm OZ at the other) or intrastromal CRIs (8 mm OZ at both centers). The lengths of the CRIs were based on published nomograms but modified to take into account posterior corneal astigmatism. Vector analysis was performed, and net corneal changes along the CRI meridian were calculated. Multiple regression analysis was performed to assess factors contributing to net corneal changes. RESULTS: Preoperatively, 9% to 18% of eyes had corneal astigmatism of ≤0.5 diopters (D), and 76% to 93% of eyes had postoperative refractive astigmatism of ≤0.5 D ( P < .05). Both penetrating and intrastromal CRIs produced significant mean net corneal changes along the CRI meridian (-0.49 to -1.21 D), and 71% to 84% of eyes had postoperative astigmatism vector prediction errors of ≤0.50 D. The 8 mm penetrating CRIs induced greater net corneal changes but more eyes with overcorrection than did the intrastromal and 9 mm penetrating CRIs (all P < .05). Greater net corneal changes occurred with longer CRI length, higher preoperative corneal astigmatism magnitude, and preoperative against-the-rule corneal astigmatism. Nomograms based on anterior and total corneal astigmatism are proposed. CONCLUSIONS: Both penetrating and intrastromal CRIs were effective in reducing corneal astigmatism during cataract surgery.

ACE2 gene transfer ameliorates vasoreparative dysfunction in CD34+ cells derived from diabetic older adults.

Diabetes increases the risk for ischemic vascular diseases, which is further elevated in older adults. Bone marrow-derived hematopoietic CD34+ stem/progenitor cells have the potential of revascularization; however, diabetes attenuates vasoreparative functions. Angiotensin-converting enzyme 2 (ACE2) is the vasoprotective enzyme of renin-angiotensin system in contrast with the canonical angiotensin-converting enzyme (ACE). The present study tested the hypothesis that diabetic dysfunction is associated with ACE2/ACE imbalance in hematopoietic stem/progenitor cells (HSPCs) and that increasing ACE2 expression would restore reparative functions. Blood samples from male and female diabetic (n=71) or nondiabetic (n=62) individuals were obtained and CD34+ cells were enumerated by flow cytometry. ACE and ACE2 enzyme activities were determined in cell lysates. Lentiviral (LV) approach was used to increase the expression of soluble ACE2 protein. Cells from diabetic older adults (DB) or nondiabetic individuals (Control) were evaluated for their ability to stimulate revascularization in a mouse model of hindlimb ischemia (HLI). DB cells attenuated the recovery of blood flow to ischemic areas in nondiabetic mice compared with that observed with Control cells. Administration of DB cells modified with LV-ACE2 resulted in complete restoration of blood flow. HLI in diabetic mice resulted in poor recovery with amputations, which was not reversed by either Control or DB cells. LV-ACE2 modification of Control or DB cells resulted in blood flow recovery in diabetic mice. In vitro treatment with Ang-(1-7) modified paracrine profile in diabetic CD34+ cells. The present study suggests that vasoreparative dysfunction in CD34+ cells from diabetic older adults is associated with ACE2/ACE imbalance and that increased ACE2 expression enhances the revascularization potential.

Evaluation of the Repeatability and Reproducibility of Corneal Epithelial Thickness Mapping for a 9-mm Zone Using Optical Coherence Tomography.

PURPOSE: To evaluate the repeatability and between-machine/operator reproducibility of optical coherence tomography (RTVue-XR) for mapping corneal epithelial thickness (ET) and corneal thickness (CT) over a 9-mm zone. METHODS: In 5 groups of eyes (normal, contact lens, dry eye, post-LASIK/PRK, and keratoconus), corneal ET and CT were evaluated in 25 areas in the following 4 regions: 1) 1 central zone within 0 to 2.0 mm diameter, 2) 8 paracentral zones from 2.0 to 5.0 mm diameter, 3) 8 midperipheral zones from 5.0 to 7.0 mm diameter, and 4) 8 peripheral zones from 7.0 to 9.0 mm diameter. Three devices with designated operators were used to obtain 3 scans per device for each eye. The repeatability, reproducibility, and coefficient of variation were calculated. RESULTS: For all areas up to 9 mm diameter, in normal eyes, contact lens eyes, dry eyes, post- LASIK/PRK eyes, and keratoconic eyes, repeatability and reproducibility ranged from 0.7 to 1.5, 1.0 to 2.6, 0.9 to 2.0, 0.7 to 2.5, and 1.1 to 2.3 µm for ET and 1.5 to 8.3, 2.3 to 12.1, 1.7 to 14.2, 1.4 to 13.7, and 6.9 to 18.9 µm for CT, respectively. The ranges of coefficient of variation values were 1.2% to 3.0%, 1.9% to 5.5%, 1.8% to 4.3%, 1.3% to 5.2%, and 2.2% to 4.5% for ET and 0.3% to 1.2%, 0.4% to 1.8%, 0.4% to 2.1%, 0.3% to 2.0%, and 1.2% to 3.0% for CT, respectively. CONCLUSIONS: Optical coherence tomography produced excellent repeatability and reproducibility for corneal ET and CT measurements up to a 9-mm zone in normal eyes and eyes with different corneal conditions. The CT measurements in keratoconic eyes were more variable than those in eyes with other corneal conditions.

Preoperative Prediction of the Optimal Toric Intraocular Lens Alignment Meridian.

PURPOSE: To determine whether any of three keratometry devices is superior to the others in predicting the ideal toric intraocular lens (IOL) alignment meridian. METHODS: A retrospective review was performed to identify patients who underwent cataract phacoemulsification with toric IOL implantation from November 2014 to November 2016 at a single academic institution. For each patient, corneal measurements were performed with an optical low-coherence reflectometer/autokeratometer (OLCR), a dual Scheimpflug/Placido analyzer, and a color light-emitting diode (LED) topographer. Postoperatively, the ideal toric IOL alignment meridian that would have resulted in the least amount of residual astigmatism was determined using the online Berdhal & Hardten Toric Results Analyzer (BHTRA). To determine the prediction error, this ideal alignment meridian was compared to the corneal meridian with the highest refractive power, as provided by the three devices. RESULTS: Fifty-six eyes of 56 patients were included in the study. The mean absolute errors in the toric IOL alignment meridians of the color LED topographer, dual Scheimpflug/Placido analyzer, and OLCR were 5.2° ± 5.2°, 7.6° ± 5.7°, and 5.4° ± 5.1°, respectively. There was no significant difference in the ability of each device to predict the ideal alignment meridian as determined by the BHTRA. CONCLUSIONS: The color LED topographer, dual Scheimpflug/Placido analyzer, and OLCR may all be used to preoperatively determine the best alignment meridian for toric IOL placement. Surgeons should use their best judgment in determining which device to use in preoperative planning for individual patients. [J Refract Surg. 2018;34(8):515-520.].

Gonioscopy-assisted Transluminal Trabeculotomy: An Ab Interno Circumferential Trabeculotomy: 24 Months Follow-up.

PURPOSE: The purpose of this study was to provide 24-month follow-up on surgical success and safety of an ab interno circumferential 360-degree trabeculotomy. METHODS: Chart review of patients who underwent a gonioscopy-assisted transluminal trabeculotomy (GATT) procedure was performed by 4 of the authors (D.S.G., O.S., R.L.F., and D.G.G.). The surgery was performed in adults with various types of open-angle glaucoma with preoperative intraocular pressures (IOPs) of ≥18 mm Hg. RESULTS: In total, 198 patients aged 24 to 89 years underwent the GATT procedure with at least 18 months follow-up. Patients with primary open-angle glaucoma had an average IOP decrease of 9.2 mm Hg at 24 months with an average decrease of 1.43 glaucoma medications. The mean percentage of IOP decrease in these primary open-angle glaucoma groups at 24 months was 37.3%. In secondary open-angle glaucoma, at 24 months there was an average decrease in IOP of 14.1 mm Hg on an average of 2.0 fewer medications. The mean percentage of IOP decrease in the secondary open-angle glaucoma groups at 24 months was 49.8%. The cumulative proportion of failure at 24 months ranged from 0.18 to 0.48, depending on the group. In all 6 study groups, at all 5 postoperative time points (3, 6, 12, 18, and 24 mo) the mean IOP and reduction in glaucoma medications was significantly reduced from baseline (P<0.001) with the exception of one time point. CONCLUSIONS: The 24-month results demonstrate that GATT is relatively safe and effective in treating various forms of open-angle glaucoma. The long-term results for GATT are relatively equivalent to those previously reported for GATT and ab externo trabeculotomy studies.

Accuracy of 8 intraocular lens calculation formulas in relation to anterior chamber depth in patients with normal axial lengths.

PURPOSE: To determine the effect of anterior chamber depth (ACD) on the accuracy of 8 intraocular lens calculation formulas in patients with normal axial lengths (ALs). SETTING: Baylor College of Medicine, Alkek Eye center, Houston, Texas, USA. DESIGN: Retrospective case series. METHODS: Patients having cataract surgery with ALs between 22.0 mm and 25.0 mm were divided into 3 groups based on their preoperative ACD measurement. The mean prediction errors, mean absolute errors (MAEs), and median absolute errors for each group were calculated. RESULTS: For the ACD of 3.0 mm or less group and the ACD of 3.5 mm or more group, the Barrett Universal II, Holladay 2, Haigis, and Olsen ray-tracing formulas had mean prediction error values that were not significantly different from zero. For the ACD of 3.01 to 3.49 mm group, all formulas had mean prediction error values that were not significantly different from zero. For the ACD of 3.0 mm or less group, the Barrett Universal II formula had a smaller median absolute error than the Haigis, Hoffer Q, and Olsen optical low-coherence reflectometry (OLCR) (Lenstar) formulas and a smaller MAE than the Hoffer Q, Hill-RBF, and Olsen OLCR (P < .05). In the ACD of 3.5 mm or more group, the Barrett MAE was smaller than the Hoffer Q (P < .05); however, there were no significant differences between median absolute errors. CONCLUSION: In eyes with normal ALs, taking preoperative ACD values into consideration might improve refractive outcomes.

Refractive outcomes after multifocal intraocular lens exchange.

PURPOSE: To evaluate the refractive outcomes after multifocal intraocular lens (IOL) exchange. SETTING: Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, USA. DESIGN: Retrospective case series. METHODS: Patients had multifocal IOL explantation followed by IOL implantation. Outcome measures included type of IOL, surgical indication, corrected distance visual acuity (CDVA), and refractive prediction error. RESULTS: The study comprised 29 patients (35 eyes). The types of IOLs implanted after multifocal IOL explantation included in-the-bag IOLs (74%), iris-sutured IOLs (6%), sulcus-fixated IOLs with optic capture (9%), sulcus-fixated IOLs without optic capture (9%), and anterior chamber IOLs (3%). The surgical indication for exchange included blurred vision (60%), photic phenomena (57%), photophobia (9%), loss of contrast sensitivity (3%), and multiple complaints (29%). The CDVA was 20/40 or better in 94% of eyes before the exchange and 100% of eyes after the exchange (P = .12). The mean refractive prediction error significantly decreased from 0.22 ± 0.81 diopter (D) before the exchange to -0.09 ± 0.53 D after the exchange (P < .05). The median absolute refractive prediction error significantly decreased from 0.43 D before the exchange to 0.23 D after the exchange (P < .05). CONCLUSIONS: Multifocal IOL exchange can be performed safely with good visual outcomes using different types of IOLs. A lower refractive prediction error and a higher likelihood of 20/40 or better vision can be achieved with the implantation of the second IOL compared with the original multifocal IOL, regardless of the final IOL position.

Secondary intraocular lens implantation: Complication rates, visual acuity, and refractive outcomes.

PURPOSE: To compare complication rates, visual acuity, and refractive outcomes of secondary intraocular lens (IOLs) implantation. SETTING: Department of Ophthalmology, Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, USA. DESIGN: Retrospective case series. METHODS: All secondary IOLs placed by the anterior segment service were reviewed. Preoperative data, operative reports, and data from each subsequent postoperative visit were evaluated. Patients were divided into 5 groups based on the final IOL position: (1) sulcus with optic capture, (2) sulcus without optic capture, (3) anterior chamber (AC), (4) iris-fixated, and (5) transscleral-sutured. Complication rates, visual acuity, and refractive outcomes were compared for each group. RESULTS: The sulcus with and without optic capture groups had the lowest complication rates and best visual acuity outcomes. There was no difference in final corrected distance visual acuity (CDVA) between the transscleral-sutured IOL, iris-fixated IOL, and AC IOL groups, although the AC IOL group had the lowest rates of early postoperative complications and a significant improvement in vision. The transscleral-sutured IOL group had the highest complication rates, and 25% of patients in the iris-fixated IOL group lost 2 or more lines of CDVA. CONCLUSIONS: When a secondary IOL cannot be placed within the capsular bag, sulcus with optic capture is the best alternative, followed by sulcus without optic capture. There was no difference in visual acuity outcomes between transscleral-sutured IOLs, iris-fixated IOLs, and AC IOLs. Anterior chamber IOLs resulted in fewer early complications.

Accuracy of toric intraocular lens axis alignment using a 3-dimensional computer-guided visualization system.

PURPOSE: To evaluate the accuracy of toric intraocular lens (IOL) alignment in femtosecond laser-assisted cataract surgery using the Truevision 3-dimensional (3-D) computer-guided visualization system compared with a manual marking method. SETTING: Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, USA. DESIGN: Retrospective comparative case series. METHODS: Preoperatively, all patients had corneal topography measurements with a color light-emitting diode topographer. The 3-D system used the anterior keratometry values to create an optimized plan for the toric IOL alignment. Intrastromal marks were created by the femtosecond laser at the intended toric meridian, guided by manual ink marks placed at the 3 o'clock and 9 o'clock limbus with the patient sitting upright. Intraoperatively, the 3-D system was used to align the IOL and measure the angular position of the femtosecond marks relative to the IOL meridian. Three weeks postoperatively, the manifest refraction, corrected distance visual acuity, and toric IOL alignment were recorded. RESULTS: The mean 3-D imaging error was -0.58 degrees ± 3.90 (SD) (range -9 to 5 degrees), and the mean manual ink error was -0.27 ± 3.65 degrees (range -8 to 5 degrees); neither was statistically significantly different from zero (P = .28 and P = .76, respectively). The mean absolute errors were 2.96 ± 2.54 degrees and 2.88 ± 2.18 degrees, respectively. CONCLUSION: The 3-D computer-guided system and manual marking combined with femtosecond laser marks were similar in accuracy for toric alignment. FINANCIAL DISCLOSURES: Dr. Wang received research support from Ziemer USA, Inc. Dr. Weikert is a consultant to Ziemer USA, Inc. Dr. Koch is a consultant to Alcon Laboratories, Inc., and Abbott Medical Optics, Inc., and received research support from Ziemer USA, Inc., i-Optics Corp, and Truevision Systems. None of the other authors has a financial or proprietary interest in any material or method mentioned.

Gonioscopy assisted transluminal trabeculotomy: an ab interno circumferential trabeculotomy for the treatment of primary congenital glaucoma and juvenile open angle glaucoma.

BACKGROUND/AIMS: To introduce a novel ab interno 360° trabeculotomy for treating primary congenital glaucoma (PCG) and juvenile open angle glaucoma (JOAG) and report preliminary results. METHODS: A retrospective chart review of patients who underwent a gonioscopy assisted transluminal trabeculotomy (GATT) procedure by four of the authors (DSG, OS, RLF and DGG) between October 2011 and October 2013. The surgery was performed in patients ≤30 years old with a dysgenic anterior segment angle and uncontrolled PCG and JOAG. RESULTS: Fourteen eyes of 10 patients underwent GATT with follow-up >12 months (12-33 months; mean 20.4). Patients ranged in age from 17 months to 30 years (mean=18.4 years), and five (50%) were female patients. No complications occurred during or following surgery except for early postoperative hyphema in five (36%) of eyes, all cleared by 1 month. The mean intraocular pressure (IOP) decreased from 27.3 to 14.8 mm Hg and the mean number of medications required decreased from 2.6 to 0.86. Five eyes had a drop in IOP ≥15 mm Hg (range 15-39). CONCLUSIONS: The preliminary results and safety for GATT, a minimally invasive conjunctival sparing circumferential trabeculotomy, are promising and at least equivalent to previous results for ab externo trabeculotomy for the treatment of PCG and JOAG. All eyes in the study were considered a clinical success.

Repeatability of posterior and total corneal curvature measurements with a dual Scheimpflug-Placido tomographer.

PURPOSE: To evaluate the repeatability of the Galilei G4 dual Scheimpflug analyzer in measuring simulated keratometric, total, and posterior corneal curvature in normal and post-refractive surgery eyes. SETTING: Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, USA. DESIGN: Prospective evaluation of diagnostic technology. METHODS: A single observer performed 3 consecutive measurements in 1 eye of each subject. The following were evaluated in both eyes and in eyes that had previous myopic excimer-laser surgery: (1) simulated keratometric corneal power and astigmatism, (2) total corneal power and astigmatism, and (3) posterior corneal power and astigmatism. Repeatability was assessed by calculating the within-subject standard deviation (Sw), coefficient of variation (CoV), and intra-class correlation coefficient (ICC). RESULTS: The study evaluated 41 normal eyes and 36 post-refractive surgery eyes. In normal eyes, the Sw was 0.08 diopters (D), 0.10 D, and 0.03 D for simulated keratometric, total, and posterior corneal power, respectively. The CoV ranged from 0.16% to 0.40%, and the ICC was 0.992 or more (P < .001) for all corneal powers. In post-refractive surgery eyes, the Sw was 0.09 D, 0.09 D, and 0.02 D for simulated keratometric, total, and posterior corneal power, respectively. The CoV ranged from 0.19% to 0.32%, and the ICC was 0.990 or more (P < .001) for all corneal powers. For posterior corneal astigmatism, the ICC was 0.814 and 0.886 for normal and post-refractive surgery eyes, respectively. CONCLUSIONS: In normal corneas and corneas that had undergone myopic excimer laser ablation, the dual Scheimpflug analyzer showed high intra-observer repeatability for simulated keratometric, total, and posterior corneal power measurements and moderate repeatability for posterior corneal astigmatism. FINANCIAL DISCLOSURE: Drs. Koch, Weikert, and Wang received research support from Ziemer USA, Inc. No other author has a financial or proprietary interest in any material or method mentioned.

Gonioscopy-assisted transluminal trabeculotomy, ab interno trabeculotomy: technique report and preliminary results.

PURPOSE: To introduce a minimally invasive, ab interno approach to a circumferential 360-degree trabeculotomy and to report the preliminary results. DESIGN: Retrospective, noncomparative cases series. PARTICIPANTS: Eighty-five eyes of 85 consecutive patients who sought treatment at Glaucoma Associates of Texas with uncontrolled open-angle glaucoma and underwent gonioscopy-assisted transluminal trabeculotomy (GATT) for whom there was at least 6 months of follow-up data. METHODS: Retrospective chart review of patients who underwent GATT by 4 of the authors (D.S.G., D.G.G., O.S., R.L.F.) between October 2011 and October 2012. The surgery was performed in adults with various open-angle glaucomas. MAIN OUTCOME MEASURES: Intraocular pressure (IOP), glaucoma medications, visual acuity, and intraoperative as well as postoperative complications. RESULTS: Eighty-five patients with an age range of 24 to 88 years underwent GATT with at least 6 months of follow-up. In 57 patients with primary open-angle glaucoma, the IOP decreased by 7.7 mmHg (standard deviation [SD], 6.2 mm Hg; 30.0% [SD, 22.7%]) with an average decrease in glaucoma medications of 0.9 (SD, 1.3) at 6 months. In this group, the IOP decreased by 11.1 mmHg (SD, 6.1 mmHg; 39.8% [SD, 16.0%]) with 1.1 fewer glaucoma medications at 12 months. In the secondary glaucoma group of 28 patients, IOP decreased by 17.2 mmHg (SD, 10.8 mmHg; 52.7% [SD, 15.8%]) with an average of 2.2 fewer glaucoma medications at 6 months. In this group, the IOP decreased by 19.9 mmHg (SD, 10.2 mmHg; 56.8% [SD, 17.4%]) with an average of 1.9 fewer medications (SD, 2.1) at 12 months. Treatment was considered to have failed in 9% (8/85) of patients because of the need for further glaucoma surgery. The cumulative proportion of failure at 1 year ranged from 0.1 to 0.32, depending on the group. Lens status or concurrent cataract surgery did not have a statistically significant effect on IOP in eyes that underwent GATT at either 6 or 12 months (P > 0.35). The most common complication was transient hyphema, seen in 30% of patients at the 1-week visit. CONCLUSIONS: The preliminary results and safety profile for GATT, a minimally invasive circumferential trabeculotomy, are promising and at least equivalent to previously published results for ab externo trabeculotomy.