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1.
Am J Ophthalmol ; 2024 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-39009239

RESUMEN

PURPOSE: To measure low perfusion area (LPA) and focal perfusion loss (FPL) in the macula using OCT angiography (OCTA) for glaucoma. DESIGN: Prospective, cross-sectional "case-control" comparison study. METHODS: A total of 60 patients with primary open-angle glaucoma (POAG) and 37 normal participants were analyzed. AngioVue 6 × 6-mm high-definition (400 × 400 transverse pixels) macular OCTA scans were performed on one eye of each participant. Flow signal was calculated using the split-spectrum amplitude-decorrelation angiography algorithm. En face ganglion cell layer plexus (GCLP) and superficial vascular complex (SVC) images were generated. Using custom software, vessel density (VD) maps were obtained by computing the fraction of area occupied by flow pixels after low-pass filtering by local averaging 41 × 41 pixels. LPA was defined by local VD below 0.5 percentile over a contiguous area above 98.5 percentile of the normal reference population. The FPL was the percent VD loss (relative to normal mean) integrated over the LPA. RESULTS: Among patients with POAG, 30 had perimetric and 30 had pre-perimetric glaucoma. The LPAGCLP-VD was 0.16±0.38 mm2 in normal and 5.78±6.30 mm2 in glaucoma subjects (P<0.001). The FPLGCLP-VD was 0.20%±0.47% in normal and 7.52%±8.84% in glaucoma subjects (P<0.001). The perimetric glaucoma diagnostic accuracy, measured by the area under the receiver operating curve, was 0.993 for LPAGCLP-VD and 0.990 for FPLGCLP-VD. The sensitivities were 96.7% and 93.3% at 95% specificity, respectively. The LPAGCLP-VD and FPLGCLP-VD had good repeatability (0.957 and 0.952 by intraclass correlation coefficient). Diagnostic accuracy was better than GCLP VD (AROC 0.950, sensitivity 83.3%) and OCT ganglion cell complex (GCC) thickness (AROC 0.927, sensitivity 80.0%), GCC focal loss volume (AROC 0.957, sensitivity 80.0%). The LPAGCLP-VD and FPLGCLP-VD correlated well with central VF mean deviations (Pearson's r=-0.716 and -0.705 respectively, both P<0.001). CONCLUSION: Assessment of macular focal perfusion loss using OCTA is useful in evaluating glaucomatous damage.

2.
Bioengineering (Basel) ; 11(6)2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38927813

RESUMEN

BACKGROUND: Recent advancements in deep learning have significantly impacted ophthalmology, especially in glaucoma, a leading cause of irreversible blindness worldwide. In this study, we developed a reliable predictive model for glaucoma detection using deep learning models based on clinical data, social and behavior risk factor, and demographic data from 1652 participants, split evenly between 826 control subjects and 826 glaucoma patients. METHODS: We extracted structural data from control and glaucoma patients' electronic health records (EHR). Three distinct machine learning classifiers, the Random Forest and Gradient Boosting algorithms, as well as the Sequential model from the Keras library of TensorFlow, were employed to conduct predictive analyses across our dataset. Key performance metrics such as accuracy, F1 score, precision, recall, and the area under the receiver operating characteristics curve (AUC) were computed to both train and optimize these models. RESULTS: The Random Forest model achieved an accuracy of 67.5%, with a ROC AUC of 0.67, outperforming the Gradient Boosting and Sequential models, which registered accuracies of 66.3% and 64.5%, respectively. Our results highlighted key predictive factors such as intraocular pressure, family history, and body mass index, substantiating their roles in glaucoma risk assessment. CONCLUSIONS: This study demonstrates the potential of utilizing readily available clinical, lifestyle, and demographic data from EHRs for glaucoma detection through deep learning models. While our model, using EHR data alone, has a lower accuracy compared to those incorporating imaging data, it still offers a promising avenue for early glaucoma risk assessment in primary care settings. The observed disparities in model performance and feature significance show the importance of tailoring detection strategies to individual patient characteristics, potentially leading to more effective and personalized glaucoma screening and intervention.

3.
Environ Sci Pollut Res Int ; 31(19): 28525-28537, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38558348

RESUMEN

Herein, novel catalysts of Fe-containing zeolite-A (Fe/zeolite-A) were synthesized by exchanging iron ions into zeolite-A framework, and short-chain organic acids (SCOAs) were employed as chelating agents. Reactive Brilliant Blue KN-R (KN-R) was used as a model pollutant to evaluate the performance of these catalysts based on the heterogeneous Fenton reaction. The results showed that Fe-OA/3A, which applied zeolite-3A as the supporter and oxalic as the chelating agent, presented the most prominent KN-R decolorization efficiency. Under the initial pH of 2.5, 0.4 mM KN-R could be totally decolorized within 20 min. However, the mineralization efficiency of KN-R was only 58.2%. Therefore, anthraquinone dyes were introduced to modify zeolite-3A. As a result, the mineralization efficiency of KN-R was elevated to 92.7% when using Alizarin Violet (AV) as the modifier. Moreover, the modified catalysts exhibited excellent stability, the KN-R decolorization efficiency could be maintained above 95.0% within 20 min after operating for nine cycles. The mechanism revealed that the Fe(II)/Fe(III) cycle was accelerated by AV-modified catalyst thus prompting the KN-R decolorization in Fenton-like system. These findings provide new insights for preparing catalysts with excellent activity and stability for dye wastewater treatment.


Asunto(s)
Hierro , Zeolitas , Zeolitas/química , Hierro/química , Colorantes/química , Contaminantes Químicos del Agua/química , Catálisis , Antraquinonas/química , Bencenosulfonatos/química , Peróxido de Hidrógeno/química
4.
J Am Med Inform Assoc ; 31(2): 456-464, 2024 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-37964658

RESUMEN

OBJECTIVE: Surgical outcome prediction is challenging but necessary for postoperative management. Current machine learning models utilize pre- and post-op data, excluding intraoperative information in surgical notes. Current models also usually predict binary outcomes even when surgeries have multiple outcomes that require different postoperative management. This study addresses these gaps by incorporating intraoperative information into multimodal models for multiclass glaucoma surgery outcome prediction. MATERIALS AND METHODS: We developed and evaluated multimodal deep learning models for multiclass glaucoma trabeculectomy surgery outcomes using both structured EHR data and free-text operative notes. We compare those to baseline models that use structured EHR data exclusively, or neural network models that leverage only operative notes. RESULTS: The multimodal neural network had the highest performance with a macro AUROC of 0.750 and F1 score of 0.583. It outperformed the baseline machine learning model with structured EHR data alone (macro AUROC of 0.712 and F1 score of 0.486). Additionally, the multimodal model achieved the highest recall (0.692) for hypotony surgical failure, while the surgical success group had the highest precision (0.884) and F1 score (0.775). DISCUSSION: This study shows that operative notes are an important source of predictive information. The multimodal predictive model combining perioperative notes and structured pre- and post-op EHR data outperformed other models. Multiclass surgical outcome prediction can provide valuable insights for clinical decision-making. CONCLUSIONS: Our results show the potential of deep learning models to enhance clinical decision-making for postoperative management. They can be applied to other specialties to improve surgical outcome predictions.


Asunto(s)
Aprendizaje Profundo , Glaucoma , Humanos , Glaucoma/cirugía , Aprendizaje Automático , Redes Neurales de la Computación , Resultado del Tratamiento
5.
Ophthalmol Sci ; 4(1): 100409, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38054107

RESUMEN

Objective: To determine the impact of documentation workflow on the accuracy of coded diagnoses in electronic health records (EHRs). Design: Cross-sectional study. Participants: All patients who completed visits at the Casey Eye Institute Retina Division faculty clinic between April 7, 2022 and April 13, 2022. Main Outcome Measures: Agreement between coded diagnoses and clinical notes. Methods: We assessed the rate of agreement between the diagnoses in the clinical notes and the coded diagnosis in the EHR using manual review and examined the impact of the documentation workflow on the rate of agreement in an academic retina practice. Results: In 202 visits by 8 physicians, 78% (range, 22%-100%) had an agreement between the coded diagnoses and the clinical notes. When physicians integrated the diagnosis code entry and note composition, the rate of agreement was 87.9% (range, 62%-100%). For those who entered the diagnosis codes separately from writing notes, the agreement was 44.4% (22%-50%, P < 0.0001). Conclusion: The visit-specific agreement between the coded diagnosis and the progress note can vary widely by workflow. The workflow and EHR design may be an important part of understanding and improving the quality of EHR data. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

6.
Transl Vis Sci Technol ; 12(9): 10, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37713187

RESUMEN

Purpose: This cross-sectional study aimed to investigate the sectoral variance of optical coherence tomography (OCT) and OCT angiography (OCTA) glaucoma diagnostic parameters across eyes with varying degrees of refractive error. Methods: Healthy participants, including individuals with axial ametropia, enrolled in the Hong Kong FAMILY cohort were imaged using the Avanti/AngioVue OCT/OCTA system. The OCT and OCTA parameters obtained include peripapillary nerve fiber layer thickness (NFLT), peripapillary nerve fiber layer plexus capillary density (NFLP-CD), and macular ganglion cell complex thickness (GCCT). Sectoral measurements of NFLT, NFLP-CD, and GCCT were based on sectors and hemispheres. Results: A total of 1339 eyes from 791 participants were stratified based on spherical equivalent refraction: high myopia (<-6 D), low myopia (-6 D to -1 D), emmetropia (-1 D to 1 D), and hyperopia (>1 D). Multivariable broken stick regression models, accounting for age, sex, and signal strength, showed that all NFLT sectors except temporally, the inferior GCCT hemisphere, and half of the NFLP-CD sectors were more affected by ametropia-related covariates than the corresponding global parameters. As expected, the false-positive rates in those sectors were elevated. Finally, sector-specific axial length (AL) and spherical equivalent (SE) adjustments helped reduce the elevated false-positive rates. Conclusions: The effect of optical magnification is even more prominent among sectors than the global parameters. AL- and SE-based adjustments should be individualized to each sector to mitigate this magnification bias effectively. Translational Relevance: Identifying sectoral differences among diagnostic parameters and adopting these sector-based adjustments into commercial OCT systems will hopefully reduce false-positive rates related to refractive error.


Asunto(s)
Glaucoma , Miopía , Errores de Refracción , Humanos , Tomografía de Coherencia Óptica , Estudios Transversales , Errores de Refracción/diagnóstico , Glaucoma/diagnóstico , Angiografía
8.
Transl Vis Sci Technol ; 11(9): 8, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-36112104

RESUMEN

Purpose: The purpose of this study was to correct refractive error-associated bias in optical coherence tomography (OCT) and OCT angiography (OCTA) glaucoma diagnostic parameters. Methods: OCT and OCTA imaging were obtained from participants in the Hong Kong FAMILY cohort. The Avanti/AngioVue OCT/OCTA system was used to measure the peripapillary nerve fiber layer thickness (NFLT), peripapillary nerve fiber layer plexus capillary density (NFLP-CD), macular ganglion cell complex thickness (GCCT), and macular superficial vascular complex vascular density (SVC-VD). Healthy eyes, including ones with axial ametropia, were enrolled for analysis. Results: A total of 1346 eyes from 792 participants were divided into 4 subgroups: high myopia (<-6D), low myopia (-6D to -1D), emmetropia (-1D to 1D), and hyperopia (>1D). After accounting for age, sex, and signal strength, multivariable regression showed strong dependence in most models for NFLT, GCCT, and NFLP-CD on axial eye length (AL), spherical equivalent (SE) refraction, and apparent optic disc diameter (DD). Optical analysis indicated that AL-related transverse optical magnification variations predominated over anatomic variations and were responsible for these trends. Compared to the emmetropic group, the false positive rates were significantly (Chi-square test P < 0.003) elevated in both myopia groups for NFLT, NFLP-CD, and GCCT. Regression-based adjustment of these diagnostic parameters with AL or SE significantly (McNemar test P < 0.03) reduced the elevated false positive rates. Conclusions: Myopic eyes are biased to have lower NFLT, GCCT, and NFLP-CD measurements. AL- and SE-based adjustments were effective in mitigating this bias. Translational Relevance: Adoption of these adjustments into commercial OCT systems may reduce false positive rates related to refractive error.


Asunto(s)
Glaucoma , Miopía , Disco Óptico , Errores de Refracción , Angiografía , Glaucoma/diagnóstico , Humanos , Miopía/diagnóstico por imagen , Disco Óptico/diagnóstico por imagen , Errores de Refracción/diagnóstico , Tomografía de Coherencia Óptica
9.
Am J Ophthalmol Case Rep ; 28: 101711, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36164560

RESUMEN

Purpose: To report the distinct pattern of retinal perfusion loss captured on optical coherence tomographic angiography (OCTA) in a case of compressive optic neuropathy associated with pituitary adenoma. Observations: A 51-year-old male had bitemporal hemianopia caused by a pituitary adenoma that compressed the optic chiasm. OCTA scans in both eyes showed peripapillary nerve fiber layer plexus defects in the nasal hemispheres and papillomacular corridors. On macular scans, the ganglion cell layer plexus showed papillomacular defects. The perfusion defects corresponded with thinning on structural OCT measurement and loss of sensitivity on visual field tests. Conclusions and importance: Chiasm compression produces a characteristic pattern of perfusion loss that can be recognized OCTA. This knowledge may be useful in the diagnosis and classification of optic neuropathies.

10.
Br J Ophthalmol ; 106(12): 1703-1709, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-34183324

RESUMEN

PURPOSE: To assess the effects of algorithms and covariates in glaucoma diagnosis with optical coherence tomography angiography (OCTA). METHODS: In this prospective cross-sectional study, one eye each of 36 normal controls and 64 patients with glaucoma underwent 4.5 mm disc-centred and 6 mm macula-centred OCTA scans. The peripapillary nerve fibre layer plexus capillary density (NFLP-CD) and macular superficial vascular complex vessel density (SVC-VD) were measured using both a commercial algorithm (AngioAnalytics) and a custom algorithm (Center for Ophthalmic Optics & Lasers Angiography Reading Toolkit (COOL-ART)). The nerve fibre layer and ganglion cell complex thicknesses were measured on structural OCT. RESULTS: The overall peripapillary NFLP-CD and macular SVC-VD measured with the two algorithms were highly correlated but poorly agreed. Among the normal controls, the perfusion measurements made by both algorithms were significantly correlated with age. AngioAnalytics measurements were also correlated with signal strength index, while COOL-ART measurements were not. These covariates were adjusted. The diagnostic accuracy, measured as the area under the receiver operating characteristic curve for glaucoma detection, was not significantly different between algorithms, between structural and perfusion parameters and between the peripapillary and macular regions (All p>0.05). The macular SVC-VD in the 6 mm square had a significantly higher diagnostic accuracy than that of the central 3 mm square area (p=0.005). CONCLUSIONS: AngioAnalytics and COOL-ART vessel density measurements are not interchangeable but potentially interconvertible. Age and signal strength are significant covariates that need to be considered. Both algorithms and both peripapillary and macular perfusion parameters have similarly good diagnostic accuracy comparable to structural OCT. A larger macular analytic area provides higher diagnostic accuracy.


Asunto(s)
Glaucoma , Disco Óptico , Humanos , Tomografía de Coherencia Óptica/métodos , Disco Óptico/irrigación sanguínea , Angiografía con Fluoresceína/métodos , Vasos Retinianos/diagnóstico por imagen , Vasos Retinianos/fisiología , Estudios Prospectivos , Estudios Transversales , Presión Intraocular , Glaucoma/diagnóstico , Algoritmos
11.
Nurs Res ; 71(2): 104-110, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34967828

RESUMEN

BACKGROUND: The COVID-19 pandemic has significantly affected healthcare institutions, introducing new challenges for nurse leaders and their colleagues. However, little is known about how the pandemic has specifically affected the lives of these leaders and what methods and strategies they are using to overcome pandemic-related challenges. OBJECTIVES: The aim of this study was to examine the effect of the 2019 pandemic on emerging healthcare leaders and highlight methods and strategies they used to overcome pandemic-related challenges. METHODS: The participants in this study represent a diverse group of interprofessional healthcare faculty enrolled in a transformational leadership course (Paths to Leadership) when the pandemic first appeared. Three months into the pandemic, the leadership cohort was invited to participate in this qualitative study, exploring four questions: Q1: How have you transformed your working styles in response to the pandemic? Q2: How have you adjusted your personal life in response to the pandemic? Q3: How have you used leadership skills learned from Paths to Leadership during the pandemic? Q4: What lessons have you learned from the pandemic? Participant narratives were analyzed by a team of nurse researchers using conventional qualitative content analysis. RESULTS: Themes for Q1 (working styles) included shifted from face-to-face to telework, faced novel disease and decisions, worked more from home, and challenged to maintain contact with professional peers and team. Themes for Q2 (personal life) included accommodate adults working and children learning from home, looked for and found the positive, and continue to struggle. Themes for Q3 (leadership skills) included reflective practice, listening, holding, and reframing. Finally, themes for Q4 (pandemic lessons) included leadership, human connection, be prepared, taking care of ourselves, and connecting with nature. DISCUSSION: The 2019 pandemic brought hardships and opportunities to faculty members enrolled in an interprofessional transformational leadership course. In conjunction with this course, the pandemic provided a unique opportunity for participants to apply newly acquired relationship building, positive organizational psychology, and reframing skills during a time of crisis. Nursing leaders, whose educational offerings may be immediately "put to the test," may find our lessons learned helpful as they develop strategies to cope with unanticipated future challenges.


Asunto(s)
COVID-19 , Adulto , Niño , Personal de Salud , Humanos , Liderazgo , Pandemias , SARS-CoV-2
12.
Exp Biol Med (Maywood) ; 246(20): 2214-2221, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34521225

RESUMEN

This study was designed to evaluate iVue Spectral-domain optical coherence tomography (SD-OCT) effectiveness in screening for eye disease compared to clinical examination. Subjects were recruited from the Casey Eye Community Outreach Program Mobile Clinic during its routinely scheduled outreach clinics to indigent, underserved populations throughout Oregon. Macular optical coherence tomography interpretation and automated optical coherence tomography analysis were compared to the clinical examination, with specific attention to findings indicative of retinal abnormalities, risks for glaucoma, and narrow angles. As a result, a total of 114 subjects were included in this study. In diabetics, optical coherence tomography and clinical exam were in fair agreement (kappa = 0.39), with 22% of eyes having abnormal findings on macular optical coherence tomography and 26% of eyes having diabetic retinopathy or diabetic macular edema on fundus exam. In non-diabetics, optical coherence tomography and clinical exam were in fair agreement (kappa = 0.28), with 11% of eyes having abnormal findings on macular optical coherence tomography and 9% on fundus exam. Using optical coherence tomography ganglion cell complex and retinal nerve fiber layer analysis, 18% of eyes were found to be glaucoma suspects, whereas clinical exam of cup-to-disc ratio detected 8% and intraocular pressure 5%. Agreements between optical coherence tomography and other methods were poor (kappa < 0.11) for glaucoma suspect. Anterior segment optical coherence tomography of the angle found 8% of eyes to have occludable angles, whereas slit lamp and gonioscopy found 5% of eyes to have narrow angles, with moderate agreement (kappa = 0.57). In summary, optical coherence tomography detected additional retinal abnormalities, glaucoma suspects, and narrow angles compared to clinical exam alone and may serve as a useful adjunct to the clinical exam in screening for eye disease in a low-risk, medically underserved, ethnically diverse population.


Asunto(s)
Retinopatía Diabética/diagnóstico , Glaucoma de Ángulo Cerrado/diagnóstico , Unidades Móviles de Salud , Retina/patología , Tomografía de Coherencia Óptica/métodos , Trastornos de la Visión/diagnóstico por imagen , Adulto , Complicaciones de la Diabetes/patología , Diabetes Mellitus/patología , Femenino , Fondo de Ojo , Gonioscopía , Humanos , Edema Macular/diagnóstico , Masculino , Área sin Atención Médica , Persona de Mediana Edad , Estudios Prospectivos , Retina/anomalías , Trastornos de la Visión/diagnóstico , Trastornos de la Visión/patología , Poblaciones Vulnerables
13.
Transl Vis Sci Technol ; 10(6): 9, 2021 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-34111254

RESUMEN

Purpose: To evaluate nerve fiber layer (NFL) reflectance for glaucoma diagnosis. Methods: Participants were imaged with 4.5 × 4.5 mm volumetric disc scans using spectral-domain optical coherence tomography. The normalized NFL reflectance map was processed by an azimuthal filter to reduce directional reflectance bias caused by variation of beam incidence angle. The peripapillary area of the map was divided into 160 superpixels. Average reflectance was the mean of superpixel reflectance. Low-reflectance superpixels were identified as those with NFL reflectance below the fifth percentile normative cutoff. Focal reflectance loss was measured by summing loss in low-reflectance superpixels. Results: Thirty-five normal, 30 preperimetric, and 35 perimetric glaucoma participants were enrolled. Azimuthal filtering improved the repeatability of the normalized NFL reflectance, as measured by the pooled superpixel standard deviation (SD), from 0.73 to 0.57 dB (P < 0.001, paired t-test) and reduced the population SD from 2.14 to 1.78 dB (P < 0.001, t-test). Most glaucomatous reflectance maps showed characteristic patterns of contiguous wedge or diffuse defects. Focal NFL reflectance loss had significantly higher diagnostic sensitivity than the best NFL thickness parameter (from map or profile): 77% versus 55% (P < 0.001) in glaucoma eyes with the specificity fixed at 99%. Conclusions: Azimuthal filtering reduces the variability of NFL reflectance measurements. Focal NFL reflectance loss has excellent glaucoma diagnostic accuracy compared to the standard NFL thickness parameters. The reflectance map may be useful for localizing NFL defects. Translational Relevance: The high diagnostic accuracy of NFL reflectance may make population-based screening feasible.


Asunto(s)
Glaucoma , Disco Óptico , Glaucoma/diagnóstico , Humanos , Presión Intraocular , Fibras Nerviosas , Estudios Prospectivos , Células Ganglionares de la Retina , Campos Visuales
14.
AMIA Annu Symp Proc ; 2021: 773-782, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35308943

RESUMEN

Accuracy of medication data in electronic health records (EHRs) is crucial for patient care and research, but many studies have shown that medication lists frequently contain errors. In contrast, physicians often pay more attention to the clinical notes and record medication information in them. The medication information in notes may be used for medication reconciliation to improve the medication lists' accuracy. However, accurately extracting patient's current medications from free-text narratives is challenging. In this study, we first explored the discrepancies between medication documentation in medication lists and progress notes for glaucoma patients by manually reviewing patients' charts. Next, we developed and validated a named entity recognition model to identify current medication and adherence from progress notes. Lastly, a prototype tool for medication reconciliation using the developed model was demonstrated. In the future, the model has the potential to be incorporated into the EHR system to help with realtime medication reconciliation.


Asunto(s)
Glaucoma , Procesamiento de Lenguaje Natural , Documentación , Registros Electrónicos de Salud , Glaucoma/tratamiento farmacológico , Humanos , Conciliación de Medicamentos
15.
Ophthalmology ; 127(4): 484-491, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31899032

RESUMEN

PURPOSE: To measure low perfusion areas (LPAs) and focal perfusion loss (FPL) in the peripapillary retina using OCT angiography (OCTA) in glaucoma. DESIGN: Prospective, observational study. PARTICIPANTS: A total of 47 patients with primary open-angle glaucoma (POAG) and 36 normal participants were analyzed. METHODS: One eye of each subject was scanned using an AngioVue (Optovue, Fremont, CA) 4.5-mm OCTA scan centered on the disc. En face nerve fiber layer (NFL) plexus angiogram was generated. With the use of custom software, a capillary density map was obtained by computing the fraction of area occupied by flow pixels after low-pass filtering by local averaging 21×21 pixels. The low-perfusion map is defined by local capillary density below 0.5 percentile over a contiguous area above 98.5 percentile of the normal reference population. The LPA parameter is the cumulative area, and the FPL is the percent capillary density loss (relative to normal mean) integrated over the LPA. MAIN OUTCOME MEASURES: Peripapillary retinal LPA and FPL. RESULTS: Among patients with POAG, 3 had preperimetric glaucoma and 44 had perimetric glaucoma, with visual field (VF) mean deviation (MD) of -5.14±4.25 decibels (dB). The LPA was 3.40±2.29 mm2 in those with POAG and 0.11±0.18 mm2 in normal subjects (P < 0.001). The FPL was 21.8%±17.0% in those with POAG and 0.3%±0.7% in normal subjects (P < 0.001). The diagnostic accuracy as measured by the area under the receiver operating curve was 0.965 for both LPA and FPL, with a sensitivity of 93.7% at 95% specificity. The repeatability as measured by intraclass correlation coefficient was 0.977 for LPA and 0.958 for FPL. The FPL had excellent correlation with VF MD (Spearman's rho = -0.843), which was significantly (P = 0.008) better than the correlation between NFL thickness and VF MD (rho = 0.760). The hemispheric difference correlation between FPL and VF (Spearman's rho = 0.770) was significantly (P < 0.001) higher than the hemispheric difference correlation between LPA and VF (rho = 0.595). CONCLUSIONS: The low-perfusion map and LPA and FPL parameters are able to assess the location and severity of focal glaucoma damage with good agreement with VF.


Asunto(s)
Glaucoma de Ángulo Abierto/fisiopatología , Disco Óptico/irrigación sanguínea , Vasos Retinianos/fisiología , Anciano , Presión Arterial/fisiología , Presión Sanguínea/fisiología , Estudios Transversales , Femenino , Angiografía con Fluoresceína , Glaucoma de Ángulo Abierto/diagnóstico por imagen , Humanos , Presión Intraocular/fisiología , Masculino , Persona de Mediana Edad , Fibras Nerviosas/patología , Disco Óptico/diagnóstico por imagen , Estudios Prospectivos , Curva ROC , Células Ganglionares de la Retina/patología , Tomografía de Coherencia Óptica , Tonometría Ocular , Trastornos de la Visión/fisiopatología , Pruebas del Campo Visual , Campos Visuales/fisiología
16.
Invest Ophthalmol Vis Sci ; 55(4): 2244-50, 2014 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-24557348

RESUMEN

PURPOSE: We correlated scleral IOP to assigned IOP using pneumatonometry in cadaver eyes before and after Boston type I keratoprosthesis (KPro) implantation. METHODS: Corneal IOP and scleral IOP at the superonasal, superotemporal, inferotemporal, and inferonasal quadrants were measured using pneumatonometry in six cadaver eyes cannulated with an infusion line with assigned IOP held at 20, 30, 40, and 50 mm Hg. Measurements of scleral IOP at the same location were repeated after a KPro was implanted. Correlations between scleral IOP and assigned IOP were analyzed for the entire group of eyes, and for each individual eye before and after KPro. One eye was tested by another masked grader for interobserver variability. RESULTS: Scleral IOP measured higher than corneal IOP by a mean of 13.2 mm Hg. For group analysis, pre-KPro scleral IOP had a positive and linear correlation with assigned IOP in all quadrants (P < 0.00001), and this correlation was preserved after KPro implantation (P < 0.00001). There was strong interobserver agreement in all measurement sites (P < 0.001). In analyses of individual eyes, scleral IOP measured at the inferotemporal quadrant confirmed the strong linear association between scleral IOP and assigned IOP before and after KPro for all study eyes. A Bland-Altman plot showed that the difference in scleral IOP between pre-KPro and post-KPro eyes fell mostly within ± 5 mm Hg. CONCLUSIONS: Scleral IOP measured by pneumatonometry may be used to estimate IOP in cadaver eyes with and without keratoprosthesis. This may be a potential modality for assessing IOP for patients with corneal pathology or keratoprosthesis.


Asunto(s)
Enfermedades de la Córnea/cirugía , Presión Intraocular/fisiología , Prótesis e Implantes , Esclerótica , Tonometría Ocular/métodos , Cadáver , Enfermedades de la Córnea/fisiopatología , Humanos , Periodo Posoperatorio , Periodo Preoperatorio , Curva ROC
17.
J Neuroophthalmol ; 33(1): 51-3, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23149617

RESUMEN

We describe a vision sparing surgical approach for optic nerve glioma. A 7-year-old girl experienced declining academic performance and social withdrawal attributed to progressive disfiguring proptosis. Three years earlier, she had undergone a limited biopsy, a course of chemotherapy, and orbital radiation therapy for a right optic nerve glioma with perineural arachnoidal gliomatosis (PAG). Because of marked proptosis, another surgery was performed via a lateral orbitotomy. After cutting a window in the thickened dura of the optic nerve, rouge colored spongy tissue was suctioned from the subarachnoid space. Small, more solidified areas were excised with unipolar cautery. Care was taken to avoid identifiable blood vessels and the optic nerve, and approximately 60%-70% of the tumor was removed. The dural window was approximated with interrupted sutures. Postoperatively, there was 9 mm reduction in right proptosis and visual acuity improved to from 20/70 to 20/60. This case illustrates the possibility of debulking optic nerve gliomas without sacrificing vision. It should be stressed that this technique is only applicable to gliomas with PAG and the durability of the surgical benefit is unknown.


Asunto(s)
Aracnoides/patología , Exoftalmia/cirugía , Neuroglía/patología , Glioma del Nervio Óptico/cirugía , Nervio Óptico/cirugía , Niño , Exoftalmia/patología , Femenino , Humanos , Nervio Óptico/patología , Glioma del Nervio Óptico/patología , Resultado del Tratamiento
18.
Middle East Afr J Ophthalmol ; 19(4): 432-5, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23248552

RESUMEN

Rituximab, a monoclonal antibody to the B cell marker CD20, is becoming increasingly popular in the treatment of various orbital disorders. In this university-based interventional case series, we describe two patients with bilateral orbital and extra-orbital reactive lymphoid hyperplasia (RLH) treated with rituximab. Initially both had favorable responses; but roughly a year later recurrent disease necessitated maintenance therapy in both cases. Both again responded to additional courses of rituximab. Although recalcitrant disease may persist after treatment, rituxmab may play a role in the management of RLH with widespread involvement.


Asunto(s)
Anticuerpos Monoclonales de Origen Murino/uso terapéutico , Enfermedades Orbitales/tratamiento farmacológico , Seudolinfoma/tratamiento farmacológico , Anciano , Antígenos CD20 , Biopsia , Diagnóstico Diferencial , Estudios de Seguimiento , Humanos , Factores Inmunológicos/uso terapéutico , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Enfermedades Orbitales/diagnóstico , Seudolinfoma/diagnóstico , Rituximab , Factores de Tiempo
19.
J Hazard Mater ; 156(1-3): 568-75, 2008 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-18243544

RESUMEN

Decolorization of an anthraquinone dye, Reactive Brilliant Blue KN-R by hydrogen peroxide was examined using Fe-containing Y and ZSM-5 zeolites as heterogeneous catalysts. Catalysts were prepared by ion-exchange and coprecipitation methods, and calcined at different temperatures. The surface morphologies, crystalline phases, and chemical-state of the catalysts were characterized by scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. Influences of reaction conditions, such as dye concentration, catalyst dosage and solution pH, were evaluated and the relations between catalytic capacity and surface microstructures were discussed. The results showed that Fe-containing Y and ZSM-5 zeolites generally exhibited similar or better catalytic efficiency compared with homogeneous Fenton reagent, with Fe-containing ZSM-5 being more efficient. Synthesis method and calcination temperature affected catalytic efficiency and the stability of catalysts. Fe-containing ZSM-5, which was prepared by coprecipitation and calcined at 450 degrees C, displayed the greatest decolorization capacity. Under the conditions of initial pH 2.5, 30.0 mmol/L H(2)O(2) and 4.0 g/L catalyst, 250 mg/L KN-R could be decolorized over 90% within 20 min.


Asunto(s)
Color , Hierro/química , Zeolitas/química , Catálisis , Microscopía Electrónica de Rastreo
20.
Am J Ophthalmol ; 145(3): 409-412, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18207124

RESUMEN

PURPOSE: To determine whether clinical outcomes in bacterial keratitis are associated with antibiotic susceptibility. DESIGN: Retrospective, ancillary study using data and samples from a completed randomized clinical trial. METHODS: Forty-two patients were enrolled with culture-confirmed bacterial keratitis at Aravind Eye Hospital in South India. All patients received topical moxifloxacin and were randomized to receive either topical prednisolone phosphate or placebo. Outcomes included time to epithelialization, best spectacle-corrected visual acuity (BSCVA), and infiltrate/scar size at three months. Bacterial isolates were cultured, and minimum inhibitory concentration (MIC) to moxifloxacin was measured using Etests. Multiple linear regression was used to assess the effect of MIC on outcome, adjusting for enrollment characteristics. RESULTS: MIC was associated with three-month infiltrate/scar size: each two-fold increase in MIC was associated with a 0.33-mm average diameter increase in scar size (P=.01). MIC was not associated with three-month BSCVA (P=.71) or time to epithelialization (P=.35). CONCLUSIONS: MIC was associated with infiltrate/scar size in bacterial keratitis. An ongoing larger, multicenter trial should provide further information on whether this association is maintained across subgroups of organisms.


Asunto(s)
Antiinfecciosos/farmacología , Compuestos Aza/farmacología , Bacterias/efectos de los fármacos , Úlcera de la Córnea/microbiología , Infecciones Bacterianas del Ojo/microbiología , Quinolinas/farmacología , Antiinfecciosos/uso terapéutico , Compuestos Aza/uso terapéutico , Úlcera de la Córnea/diagnóstico , Úlcera de la Córnea/tratamiento farmacológico , Susceptibilidad a Enfermedades , Infecciones Bacterianas del Ojo/diagnóstico , Infecciones Bacterianas del Ojo/tratamiento farmacológico , Fluoroquinolonas , Humanos , Pruebas de Sensibilidad Microbiana , Moxifloxacino , Proyectos Piloto , Prednisolona/uso terapéutico , Quinolinas/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Retrospectivos , Resultado del Tratamiento , Agudeza Visual
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