Ildamaris Montes de Oca - Academia.edu (original) (raw)

Papers by Ildamaris Montes de Oca

Research paper thumbnail of ACE2 gene transfer ameliorates vasoreparative dysfunction in CD34+ cells derived from diabetic older adults

Clinical Science, 2021

Diabetes increases the risk for ischemic vascular diseases, which is further elevated in older ad... more 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 nondiabe...

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

Journal of Cataract and Refractive Surgery, 2022

PURPOSE To compare the effectiveness of penetrating vs intrastromal femtosecond laser corneal rel... more PURPOSE To compare the effectiveness of penetrating vs intrastromal femtosecond laser corneal relaxing incisions (CRI) in reducing corneal astigmatism during cataract surgery. SETTINGS Baylor College of Medicine and Mercy Clinic Eye Specialists. DESIGN Prospective randomized study. METHODS Subjects were randomly assigned to undergo paired penetrating (8-mm optical zone (OZ) at one 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, 9-18% of eyes had corneal astigmatism of ≤ 0.5 D, and 76-93% of eyes had postoperative refractive astigmatism of ≤ 0.5 D (P<0.05). Both penetrating and intrastromal CRIs produced significant mean net corneal changes along the CRI meridian (-0.49 D to -1.21 D), and 71% - 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<0.05). 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.

Research paper thumbnail of Association of optical cataract indices with cataract severity and visual function

International Ophthalmology, 2021

Purpose The purpose of this study is to determine the correlation between subjective and optical ... more Purpose The purpose of this study is to determine the correlation between subjective and optical measurements used during cataract evaluation, including the iTrace Dysfunctional Lens Index (DLI), the HD Analyzer Objective Scatter Index (OSI), Lens Opacities Classification System III (LOCS III), Visual Function-14 Questionnaire (VF-14), and the Pelli-Robson Contrast Sensitivity Chart (PRCSC). Methods Seventy eyes from 70 patients were enrolled, including all stages of age-related nuclear cataracts. The LOCS III-NO with a cutoff of 3.2 was chosen to divide the population into two groups. Eyes with corneal or retinal pathology were excluded. All patients were evaluated with the iTrace’s DLI, HD Analyzer’s OSI, LOCS III, VF-14, and the PRCSC during each follow-up visit. Correlation analyses were performed using Stata software, version 14.0, StataCorp. Results The LOCS III-NO, DLI, OSI, and VF-14 questionnaire each correlated moderately with the BCVA with a Spearman rho value of 0.37, − 0.45, 0.40, and − 0.35, respectively. The DLI correlated moderately with LOCS III-NO with a rho value of − 0.37 and with the VF-14 questionnaire with a rho value of 0.35. The OSI correlated with both the contrast sensitivity and DLI with a rho value of − 0.35 and − 0.55, respectively. Conclusions The DLI correlated with cataract symptoms (measured by the VF-14 questionnaire) in addition to BCVA. The OSI correlated moderately with contrast sensitivity and BCVA. The highest correlation was between DLI and OSI.

Research paper thumbnail of Corneal radius of curvature measurements in normal and post-refractive surgery eyes using point-source color LED and dual-Scheimpflug Placido topographer

Investigative Ophthalmology & Visual Science, 2015

Research paper thumbnail of Accuracy of toric intraocular lens alignment and predicted residual astigmatism using a 3D computer-guided visualization system in femtosecond laser-assisted cataract surgery

Investigative Ophthalmology & Visual Science, 2015

Research paper thumbnail of An Ineffective Astigmatism Analysis

Journal of Refractive Surgery, 2019

Research paper thumbnail of Preoperative Prediction of the Optimal Toric Intraocular Lens Alignment Meridian

Journal of refractive surgery (Thorofare, N.J. : 1995), 2018

To determine whether any of three keratometry devices is superior to the others in predicting the... more To determine whether any of three keratometry devices is superior to the others in predicting the ideal toric intraocular lens (IOL) alignment meridian. 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. Fifty-six eyes of 56 patients were included in the study...

Research paper thumbnail of Refractive outcomes after multifocal intraocular lens exchange

Journal of cataract and refractive surgery, 2017

To evaluate the refractive outcomes after multifocal intraocular lens (IOL) exchange. Cullen Eye ... more To evaluate the refractive outcomes after multifocal intraocular lens (IOL) exchange. Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, USA. Retrospective case series. 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. 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 erro...

Research paper thumbnail of Updates in Biometry

International ophthalmology clinics, 2017

Partial Coherence Interferometry (PCI) Optical Biometer The IOL Master 500 (Carl Zeiss Meditec AG... more Partial Coherence Interferometry (PCI) Optical Biometer The IOL Master 500 (Carl Zeiss Meditec AG, Jena, Germany), is a noncontact biometry device that uses the principle of PCI. It uses a 780-nm semiconductor diode laser and optical A-scans to determine the axial length (AL). It can also measure anterior chamber depth (ACD) and keratometry (K) based on 6 points of reference in a 2.3 mm zone. It has an accuracy of ± 0.02 mm for AL measurement, with excellent reproducibility compared with ultrasound devices. This noncontact technique is associated with increased patient comfort and decreased risk for corneal complications when compared with immersion ultrasound biometry. It also allows for patient fixation during the measurement process, which increases the likelihood of the AL measurement being directly aligned to the fovea. However, obtaining measurements can be difficult and less reliable in eyes with corneal opacities, dense posterior subcapsular cataracts (PSC), macular disease, and poor fixation.

Research paper thumbnail of Secondary intraocular lens implantation: Complication rates, visual acuity, and refractive outcomes

Journal of cataract and refractive surgery, 2017

To compare complication rates, visual acuity, and refractive outcomes of secondary intraocular le... more To compare complication rates, visual acuity, and refractive outcomes of secondary intraocular lens (IOLs) implantation. Department of Ophthalmology, Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, USA. Retrospective case series. 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. 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 t...

Research paper thumbnail of IOL Calculations in Short, Long, and Postrefractive Eyes

International Ophthalmology Clinics, 2016

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

Journal of cataract and refractive surgery, Apr 1, 2016

To evaluate the accuracy of toric intraocular lens (IOL) alignment in femtosecond laser-assisted ... more 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. Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, USA. Retrospective comparative case series. 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 acuit...

Research paper thumbnail of Repeatability of posterior and total corneal curvature measurements with a dual Scheimpflug-Placido tomographer

Journal of cataract and refractive surgery, 2015

To evaluate the repeatability of the Galilei G4 dual Scheimpflug analyzer in measuring simulated ... more 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. Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, USA. Prospective evaluation of diagnostic technology. 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). 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 c...

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

Journal of cataract and refractive surgery, 2018

To determine the effect of anterior chamber depth (ACD) on the accuracy of 8 intraocular lens cal... more 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). Baylor College of Medicine, Alkek Eye center, Houston, Texas, USA. Retrospective case series. 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. 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 Haigi...

Research paper thumbnail of Gonioscopy-Assisted Transluminal Trabeculotomy, Ab Interno Trabeculotomy

Ophthalmology, 2014

To introduce a minimally invasive, ab interno approach to a circumferential 360-degree trabeculot... more To introduce a minimally invasive, ab interno approach to a circumferential 360-degree trabeculotomy and to report the preliminary results. Retrospective, noncomparative cases series. 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. 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. Intraocular pressure (IOP), glaucoma medications, visual acuity, and intraoperative as well as postoperative complications. 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 &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; 0.35). The most common complication was transient hyphema, seen in 30% of patients at the 1-week visit. 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.

Research paper thumbnail of ACE2 gene transfer ameliorates vasoreparative dysfunction in CD34+ cells derived from diabetic older adults

Clinical Science, 2021

Diabetes increases the risk for ischemic vascular diseases, which is further elevated in older ad... more 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 nondiabe...

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

Journal of Cataract and Refractive Surgery, 2022

PURPOSE To compare the effectiveness of penetrating vs intrastromal femtosecond laser corneal rel... more PURPOSE To compare the effectiveness of penetrating vs intrastromal femtosecond laser corneal relaxing incisions (CRI) in reducing corneal astigmatism during cataract surgery. SETTINGS Baylor College of Medicine and Mercy Clinic Eye Specialists. DESIGN Prospective randomized study. METHODS Subjects were randomly assigned to undergo paired penetrating (8-mm optical zone (OZ) at one 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, 9-18% of eyes had corneal astigmatism of ≤ 0.5 D, and 76-93% of eyes had postoperative refractive astigmatism of ≤ 0.5 D (P<0.05). Both penetrating and intrastromal CRIs produced significant mean net corneal changes along the CRI meridian (-0.49 D to -1.21 D), and 71% - 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<0.05). 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.

Research paper thumbnail of Association of optical cataract indices with cataract severity and visual function

International Ophthalmology, 2021

Purpose The purpose of this study is to determine the correlation between subjective and optical ... more Purpose The purpose of this study is to determine the correlation between subjective and optical measurements used during cataract evaluation, including the iTrace Dysfunctional Lens Index (DLI), the HD Analyzer Objective Scatter Index (OSI), Lens Opacities Classification System III (LOCS III), Visual Function-14 Questionnaire (VF-14), and the Pelli-Robson Contrast Sensitivity Chart (PRCSC). Methods Seventy eyes from 70 patients were enrolled, including all stages of age-related nuclear cataracts. The LOCS III-NO with a cutoff of 3.2 was chosen to divide the population into two groups. Eyes with corneal or retinal pathology were excluded. All patients were evaluated with the iTrace’s DLI, HD Analyzer’s OSI, LOCS III, VF-14, and the PRCSC during each follow-up visit. Correlation analyses were performed using Stata software, version 14.0, StataCorp. Results The LOCS III-NO, DLI, OSI, and VF-14 questionnaire each correlated moderately with the BCVA with a Spearman rho value of 0.37, − 0.45, 0.40, and − 0.35, respectively. The DLI correlated moderately with LOCS III-NO with a rho value of − 0.37 and with the VF-14 questionnaire with a rho value of 0.35. The OSI correlated with both the contrast sensitivity and DLI with a rho value of − 0.35 and − 0.55, respectively. Conclusions The DLI correlated with cataract symptoms (measured by the VF-14 questionnaire) in addition to BCVA. The OSI correlated moderately with contrast sensitivity and BCVA. The highest correlation was between DLI and OSI.

Research paper thumbnail of Corneal radius of curvature measurements in normal and post-refractive surgery eyes using point-source color LED and dual-Scheimpflug Placido topographer

Investigative Ophthalmology & Visual Science, 2015

Research paper thumbnail of Accuracy of toric intraocular lens alignment and predicted residual astigmatism using a 3D computer-guided visualization system in femtosecond laser-assisted cataract surgery

Investigative Ophthalmology & Visual Science, 2015

Research paper thumbnail of An Ineffective Astigmatism Analysis

Journal of Refractive Surgery, 2019

Research paper thumbnail of Preoperative Prediction of the Optimal Toric Intraocular Lens Alignment Meridian

Journal of refractive surgery (Thorofare, N.J. : 1995), 2018

To determine whether any of three keratometry devices is superior to the others in predicting the... more To determine whether any of three keratometry devices is superior to the others in predicting the ideal toric intraocular lens (IOL) alignment meridian. 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. Fifty-six eyes of 56 patients were included in the study...

Research paper thumbnail of Refractive outcomes after multifocal intraocular lens exchange

Journal of cataract and refractive surgery, 2017

To evaluate the refractive outcomes after multifocal intraocular lens (IOL) exchange. Cullen Eye ... more To evaluate the refractive outcomes after multifocal intraocular lens (IOL) exchange. Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, USA. Retrospective case series. 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. 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 erro...

Research paper thumbnail of Updates in Biometry

International ophthalmology clinics, 2017

Partial Coherence Interferometry (PCI) Optical Biometer The IOL Master 500 (Carl Zeiss Meditec AG... more Partial Coherence Interferometry (PCI) Optical Biometer The IOL Master 500 (Carl Zeiss Meditec AG, Jena, Germany), is a noncontact biometry device that uses the principle of PCI. It uses a 780-nm semiconductor diode laser and optical A-scans to determine the axial length (AL). It can also measure anterior chamber depth (ACD) and keratometry (K) based on 6 points of reference in a 2.3 mm zone. It has an accuracy of ± 0.02 mm for AL measurement, with excellent reproducibility compared with ultrasound devices. This noncontact technique is associated with increased patient comfort and decreased risk for corneal complications when compared with immersion ultrasound biometry. It also allows for patient fixation during the measurement process, which increases the likelihood of the AL measurement being directly aligned to the fovea. However, obtaining measurements can be difficult and less reliable in eyes with corneal opacities, dense posterior subcapsular cataracts (PSC), macular disease, and poor fixation.

Research paper thumbnail of Secondary intraocular lens implantation: Complication rates, visual acuity, and refractive outcomes

Journal of cataract and refractive surgery, 2017

To compare complication rates, visual acuity, and refractive outcomes of secondary intraocular le... more To compare complication rates, visual acuity, and refractive outcomes of secondary intraocular lens (IOLs) implantation. Department of Ophthalmology, Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, USA. Retrospective case series. 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. 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 t...

Research paper thumbnail of IOL Calculations in Short, Long, and Postrefractive Eyes

International Ophthalmology Clinics, 2016

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

Journal of cataract and refractive surgery, Apr 1, 2016

To evaluate the accuracy of toric intraocular lens (IOL) alignment in femtosecond laser-assisted ... more 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. Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, USA. Retrospective comparative case series. 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 acuit...

Research paper thumbnail of Repeatability of posterior and total corneal curvature measurements with a dual Scheimpflug-Placido tomographer

Journal of cataract and refractive surgery, 2015

To evaluate the repeatability of the Galilei G4 dual Scheimpflug analyzer in measuring simulated ... more 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. Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, USA. Prospective evaluation of diagnostic technology. 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). 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 c...

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

Journal of cataract and refractive surgery, 2018

To determine the effect of anterior chamber depth (ACD) on the accuracy of 8 intraocular lens cal... more 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). Baylor College of Medicine, Alkek Eye center, Houston, Texas, USA. Retrospective case series. 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. 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 Haigi...

Research paper thumbnail of Gonioscopy-Assisted Transluminal Trabeculotomy, Ab Interno Trabeculotomy

Ophthalmology, 2014

To introduce a minimally invasive, ab interno approach to a circumferential 360-degree trabeculot... more To introduce a minimally invasive, ab interno approach to a circumferential 360-degree trabeculotomy and to report the preliminary results. Retrospective, noncomparative cases series. 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. 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. Intraocular pressure (IOP), glaucoma medications, visual acuity, and intraoperative as well as postoperative complications. 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 &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; 0.35). The most common complication was transient hyphema, seen in 30% of patients at the 1-week visit. 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.