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1.
Cancer Causes Control ; 33(6): 899-911, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35380304

RESUMO

PURPOSE: A disconnect often exists between those with the expertise to manage and analyze complex, multi-source data sets, and the clinical, social services, advocacy, and public health professionals who can pose the most relevant questions and best apply the answers. We describe development and implementation of a cancer informatics infrastructure aimed at broadening the usability of community cancer data to inform cancer control research and practice; and we share lessons learned. METHODS: We built a multi-level database known as The Ohio Cancer Assessment and Surveillance Engine (OH-CASE) to link data from Ohio's cancer registry with community data from the U.S. Census and other sources. Space-and place-based characteristics were assigned to individuals according to residential address. Stakeholder input informed development of an interface for generating queries based on geographic, demographic, and disease inputs and for outputting results aggregated at the state, county, municipality, or zip code levels. RESULTS: OH-CASE contains data on 791,786 cancer cases diagnosed from 1/1/2006 to 12/31/2018 across 88 Ohio counties containing 1215 municipalities and 1197 zip codes. Stakeholder feedback from cancer center community outreach teams, advocacy organizations, public health, and researchers suggests a broad range of uses of such multi-level data resources accessible via a user interface. CONCLUSION: OH-CASE represents a prototype of a transportable model for curating and synthesizing data to understand cancer burden across communities. Beyond supporting collaborative research, this infrastructure can serve the clinical, social services, public health, and advocacy communities by enabling targeting of outreach, funding, and interventions to narrow cancer disparities.


Assuntos
Relações Comunidade-Instituição , Neoplasias , Atenção à Saúde , Humanos , Informática , Neoplasias/epidemiologia , Saúde Pública , Pesquisa
2.
Ophthalmology ; 126(8): 1076-1083, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30790587

RESUMO

PURPOSE: To determine whether preoperative endothelial cell density (ECD) and postoperative ECD after Descemet stripping automated endothelial keratoplasty (DSAEK) are associated with late endothelial graft failure (LEGF) in the Cornea Preservation Time Study (CPTS). DESIGN: Cohort study within a multicenter, randomized clinical trial. PARTICIPANTS: A total of 1007 individuals (1223 study eyes), mean age 70 years, undergoing DSAEK for Fuchs' dystrophy (94% of eyes) or pseudophakic or aphakic corneal edema (PACE) (6% of eyes) and followed for up to 5 years. METHODS: Central ECD was determined by a central image analysis reading center. Preoperative ECD was determined for 1209 eyes that did not fail and 14 eyes that experienced LEGF. The ECD at 6 and 12 months after DSAEK, the change in ECD from preoperative to 6 and 12 months, surgeon-reported operative complications, and postoperative graft dislocation were investigated for an association with LEGFs unrelated to other postoperative events. Univariable and multivariable Cox proportional hazards regression models were used to assess associations. MAIN OUTCOME MEASURES: Late endothelial graft failure and its associations with pre- and postoperative ECD and operative complications. RESULTS: The cumulative probability of LEGF was 1.3% (95% confidence interval [CI], 0.8%-2.4%). Median (interquartile range [IQR]) preoperative ECDs were similar for eyes with LEGF (2523; 2367-3161) cells/mm2) and eyes without failure (2727; 2508-2973) cells/mm2) (P = 0.34). The ECD at 6 months was associated with LEGF (P < 0.001) in time-to-event analyses, whereas preoperative ECD was not (P = 0.55). The cumulative incidence (95% CI) of LEGF was 6.5% (3.0%, 14.0%) for 97 grafts with a 6-month ECD less than 1200 cells/mm2, 0.3% (0.0%, 2.4%) for 310 grafts with a 6-month ECD between 1200 and 2000 cells/mm2, and 0.6% (0.1%, 2.7%) for 589 grafts with a 6-month ECD greater than 2000 cells/mm2. In multivariable analyses, ECD at 6 months and operative complications were both associated with LEGF (P = 0.002 and P = 0.01, respectively), whereas graft dislocation was not (P = 0.61). CONCLUSIONS: In eyes undergoing DSAEK, preoperative ECD is unrelated to LEGF, whereas lower ECD at 6 months is associated with LEGF. Early endothelial cell loss after DSAEK and intraoperative complications should be minimized to improve graft survival.


Assuntos
Edema da Córnea/cirurgia , Perda de Células Endoteliais da Córnea/patologia , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior/efeitos adversos , Distrofia Endotelial de Fuchs/cirurgia , Rejeição de Enxerto/patologia , Pseudofacia/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Perda de Células Endoteliais da Córnea/etiologia , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior/métodos , Endotélio Corneano/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais
3.
J Med Imaging (Bellingham) ; 11(1): 014006, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38188935

RESUMO

Purpose: To create Guided Correction Software for informed manual editing of automatically generated corneal endothelial cell (EC) segmentations and apply it to an active learning paradigm to analyze a diverse set of post-keratoplasty EC images. Approach: An original U-Net model trained on 130 manually labeled post-Descemet stripping automated endothelial keratoplasty (EK) images was applied to 841 post-Descemet membrane EK images generating "uncorrected" cell border segmentations. Segmentations were then manually edited using the Guided Correction Software to create corrected labels. This dataset was split into 741 training and 100 testing EC images. U-Net and DeepLabV3+ were trained on the EC images and the corresponding uncorrected and corrected labels. Model performance was evaluated in a cell-by-cell analysis. Evaluation metrics included the number of over-segmentations, under-segmentations, correctly identified new cells, and endothelial cell density (ECD). Results: Utilizing corrected segmentations for training U-Net and DeepLabV3+ improved their performance. The average number of over- and under-segmentations per image was reduced from 23 to 11 with the corrected training set. Predicted ECD values generated by networks trained on the corrected labels were not significantly different than the ground truth counterparts (p=0.02, paired t-test). These models also correctly segmented a larger percentage of newly identified cells. The proposed Guided Correction Software and semi-automated approach reduced the time to accurately segment EC images from 15 to 30 to 5 min, an ∼80% decrease compared to manual editing. Conclusions: Guided Correction Software can efficiently label new training data for improved deep learning performance and generalization between EC datasets.

4.
Ophthalmology ; 120(2): 246-51, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23107581

RESUMO

PURPOSE: To assess 3-year outcomes of Descemet's stripping automated endothelial keratoplasty (DSAEK) in comparison with penetrating keratoplasty (PKP) from the Cornea Donor Study (CDS). DESIGN: Prospective, multicenter, nonrandomized clinical trial. PARTICIPANTS: A total of 173 subjects undergoing DSAEK for a moderate risk condition (principally Fuchs' dystrophy or pseudophakic corneal edema) compared with 1101 subjects undergoing PKP from the CDS. METHODS: The DSAEK procedures were performed by 2 experienced surgeons using the same donor and similar recipient criteria as for the CDS PKP procedures, performed by 68 surgeons. Graft success was assessed by Kaplan-Meier survival analysis. Central endothelial cell density (ECD) was determined from baseline donor and postoperative central endothelial images by the reading center used in the CDS Specular Microscopy Ancillary Study. MAIN OUTCOME MEASURES: Graft clarity and ECD. RESULTS: The donor and recipient demographics were comparable in the DSAEK and PKP groups, except that the proportion of Fuchs' dystrophy cases was higher in the DSAEK cohort. The 3-year survival rate did not differ significantly between DSAEK and PKP procedures performed for either Fuchs' dystrophy (96% for both; P = 0.81) or non-Fuchs' cases (86% vs. 84%, respectively; P = 0.41). Principal causes of graft failure or regraft within 3 years after DSAEK and PKP were immunologic graft rejection (0.6% vs. 3.1%), endothelial decompensation in the absence of documented rejection (1.7% vs 2.1%), unsatisfactory visual or refractive outcome (1.7% vs. 0.5%), and infection (0% vs. 1.1%), respectively. The 3-year predicted probability of a rejection episode was 9% with DSAEK versus 20% with PKP (P = 0.0005). The median 3-year cell loss for DSAEK and PKP was 46% and 51%, respectively (P = 0.33), in Fuchs' dystrophy cases and 59% and 61%, respectively (P = 0.70), in the non-Fuchs' cases. At 3 years, use of a smaller DSAEK insertion incision was associated with significantly higher cell loss (60% vs. 33% for 3.2- and 5.0-mm incisions, respectively; P = 0.0007), but not with a significant difference in graft survival (P = 0.45). CONCLUSIONS: The graft success rate and endothelial cell loss were comparable at 3 years for DSAEK and PKP procedures. A 5-mm DSAEK incision width was associated with significantly less cell loss than a 3.2-mm incision.


Assuntos
Edema da Córnea/cirurgia , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior , Endotélio Corneano/fisiologia , Distrofia Endotelial de Fuchs/cirurgia , Sobrevivência de Enxerto/fisiologia , Ceratoplastia Penetrante , Idoso , Contagem de Células , Perda de Células Endoteliais da Córnea/fisiopatologia , Feminino , Humanos , Masculino , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento
5.
Diagnosis (Berl) ; 10(3): 267-274, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37080911

RESUMO

OBJECTIVES: Identify the incidence, rate of physician recognition, diagnostic practices and cancer outcomes for unintentional weight loss (UWL). METHODS: We completed a secondary analysis of structured and unstructured EHR data collected from adult patients between January 1, 2020 and December 31, 2021. We used four common definitions to define UWL, excluding patients with known causes of weight loss, intentional weight loss, and pregnancy. Unstructured physicians' notes were used to identify both intentional weight loss (e.g. dieting) as well as physician recognition of UWL. Cancer outcomes were identified within 12 months of UWL using diagnostic codes. Physician actions (lab tests, etc.) in response to UWL were identified through manual chart review. RESULTS: Among 29,494 established primary care patients with a minimum of two weight measurements in 2020 and in 2021, we identified 290 patients who met one or more criteria for UWL (1 %). UWL was recognized by physicians in only 60 (21 %). UWL was more common and more likely to be recognized among older patients. Diagnostic practices were quite variable. A complete blood count, complete metabolic profile, and thyroid stimulating hormone level were the three most common tests ordered in response to UWL. Five patients were diagnosed with cancer within 12 months of UWL (3 in whom UWL was recognized; two in whom it was not.). CONCLUSIONS: Unintentional weight loss is poorly recognized across a diverse range of patients. A lack of research-informed guidance may explain both low rates of recognition and variability in diagnostic practices.


Assuntos
Neoplasias , Médicos , Adulto , Feminino , Gravidez , Humanos , Neoplasias/diagnóstico , Redução de Peso , Pacientes , Atenção Primária à Saúde
6.
Transl Vis Sci Technol ; 12(2): 22, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36790821

RESUMO

Purpose: This study developed machine learning (ML) classifiers of postoperative corneal endothelial cell images to identify postkeratoplasty patients at risk for allograft rejection within 1 to 24 months of treatment. Methods: Central corneal endothelium specular microscopic images were obtained from 44 patients after Descemet membrane endothelial keratoplasty (DMEK), half of whom had experienced graft rejection. After deep learning segmentation of images from all patients' last and second-to-last imaging, time points prior to rejection were analyzed (175 and 168, respectively), and 432 quantitative features were extracted assessing cellular spatial arrangements and cell intensity values. Random forest (RF) and logistic regression (LR) models were trained on novel-to-this-application features from single time points, delta-radiomics, and traditional morphometrics (endothelial cell density, coefficient of variation, hexagonality) via 10 iterations of threefold cross-validation. Final assessments were evaluated on a held-out test set. Results: ML classifiers trained on novel-to-this-application features outperformed those trained on traditional morphometrics for predicting future graft rejection. RF and LR models predicted post-DMEK patients' allograft rejection in the held-out test set with >0.80 accuracy. RF models trained on novel features from second-to-last time points and delta-radiomics predicted post-DMEK patients' rejection with >0.70 accuracy. Cell-graph spatial arrangement, intensity, and shape features were most indicative of graft rejection. Conclusions: ML classifiers successfully predicted future graft rejections 1 to 24 months prior to clinically apparent rejection. This technology could aid clinicians to identify patients at risk for graft rejection and guide treatment plans accordingly. Translational Relevance: Our software applies ML techniques to clinical images and enhances patient care by detecting preclinical keratoplasty rejection.


Assuntos
Doenças da Córnea , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior , Humanos , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/cirurgia , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior/efeitos adversos , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior/métodos , Doenças da Córnea/etiologia , Doenças da Córnea/cirurgia , Células Endoteliais , Microscopia
7.
Cornea ; 41(5): 664-668, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34839330

RESUMO

PURPOSE: The purpose of this study was to evaluate agreement between eye banks (EBs) and an image analysis reading center on endothelial cell density (ECD) determinations using the same image analysis method. METHODS: The Cornea Image Analysis Reading Center (CIARC) determined ECD with a single experienced analyst on EB-obtained central endothelial images from donors intended for keratoplasty from 2 eye banks, Eversight and Lions VisionGift, using the Konan center analysis method. The EBs performed ECD determination on their respective sets of images using the same analysis method with experienced eye bank technicians. RESULTS: The mean age of the 200 donors was 54 years (range 30-75 years). Seventy (35%) of the 200 patients were women, and 57 (29%) were diabetic. The mean ECD was 10 cells/mm2 greater by the EBs than by CIARC (P = 0.39), with 95% limits of agreement of [-304 to 323 cells/mm2]. The mean difference was not substantially changed when the difference between EBs and CIARC ECD was adjusted for sex, donor age, donor diabetes, CV, HEX, number of cells analyzed, and EBs as a random effect (estimated mean difference of 20 cells/mm2 after adjustment in a linear mixed model; P = 0.73). The EB-determined preoperative ECD was within 10% of the CIARC-determined ECD for 178 (89%) image sets, with 15 (8%) higher by >10% and 7 (3%) lower by >10%. CONCLUSIONS: Well-trained eye bank technicians achieve comparable results for ECD determination with an experienced image analyst from an image analysis reading center when the same image analysis method is used.


Assuntos
Bancos de Olhos , Leitura , Adulto , Idoso , Contagem de Células , Perda de Células Endoteliais da Córnea/diagnóstico , Células Endoteliais , Endotélio Corneano , Feminino , Humanos , Pessoa de Meia-Idade , Doadores de Tecidos
8.
Ophthalmology ; 117(3): 438-44, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20031230

RESUMO

PURPOSE: To assess outcomes 1 year after Descemet's stripping automated endothelial keratoplasty (DSAEK) in comparison with penetrating keratoplasty (PKP) from the Specular Microscopy Ancillary Study (SMAS) of the Cornea Donor Study. DESIGN: Multicenter, prospective, nonrandomized clinical trial. PARTICIPANTS: A total of 173 subjects undergoing DSAEK for a moderate risk condition (principally Fuchs' dystrophy or pseudophakic/aphakic corneal edema) compared with 410 subjects undergoing PKP from the SMAS who had clear grafts with at least 1 postoperative specular image within a 15-month follow-up period. METHODS: The DSAEK procedures were performed by 2 experienced surgeons per their individual techniques, using the same donor and similar recipient criteria as for the PKP procedures in the SMAS performed by 68 surgeons at 45 sites, with donors provided from 31 eye banks. Graft success and complications for the DSAEK group were assessed and compared with the SMAS group. Endothelial cell density (ECD) was determined from baseline donor, 6-month (range, 5-7 months), and 12-month (range, 9-15 months) postoperative central endothelial images by the same reading center used in the SMAS. MAIN OUTCOME MEASURES: Endothelial cell density and graft survival at 1 year. RESULTS: Although the DSAEK recipient group criteria were similar to the PKP group, Fuchs' dystrophy was more prevalent in the DSAEK group (85% vs. 64%) and pseudophakic corneal edema was less prevalent (13% vs. 32%, P<0.001). The regraft rate within 15 months was 2.3% (DSAEK group) and 1.3% (PKP group) (P = 0.50). Percent endothelial cell loss was 34+/-22% versus 11+/-20% (6 months) and 38+/-22% versus 20+/-23% (12 months) in the DSAEK and PKP groups, respectively (both P<0.001). Preoperative diagnosis affected endothelial cell loss over time; in the PKP group, the subjects with pseudophakic/aphakic corneal edema experienced significantly higher 12-month cell loss than the subjects with Fuchs' dystrophy (28% vs. 16%, P = 0.01), whereas in the DSAEK group, the 12-month cell loss was comparable for the 2 diagnoses (41% vs. 37%, P = 0.59). CONCLUSIONS: One year post-transplantation, overall graft success was comparable for DSAEK and PKP procedures and endothelial cell loss was higher with DSAEK.


Assuntos
Doenças da Córnea/cirurgia , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior/métodos , Endotélio Corneano/patologia , Sobrevivência de Enxerto , Ceratoplastia Penetrante/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Contagem de Células , Córnea , Feminino , Humanos , Implante de Lente Intraocular , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Complicações Pós-Operatórias , Estudos Prospectivos , Doadores de Tecidos
9.
J Med Imaging (Bellingham) ; 7(1): 014503, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32090135

RESUMO

We are developing automated analysis of corneal-endothelial-cell-layer, specular microscopic images so as to determine quantitative biomarkers indicative of corneal health following corneal transplantation. Especially on these images of varying quality, commercial automated image analysis systems can give inaccurate results, and manual methods are very labor intensive. We have developed a method to automatically segment endothelial cells with a process that included image flattening, U-Net deep learning, and postprocessing to create individual cell segmentations. We used 130 corneal endothelial cell images following one type of corneal transplantation (Descemet stripping automated endothelial keratoplasty) with expert-reader annotated cell borders. We obtained very good pixelwise segmentation performance (e.g., Dice coefficient = 0.87 ± 0.17 , Jaccard index = 0.80 ± 0.18 , across 10 folds). The automated method segmented cells left unmarked by analysts and sometimes segmented cells differently than analysts (e.g., one cell was split or two cells were merged). A clinically informative visual analysis of the held-out test set showed that 92% of cells within manually labeled regions were acceptably segmented and that, as compared to manual segmentation, automation added 21% more correctly segmented cells. We speculate that automation could reduce 15 to 30 min of manual segmentation to 3 to 5 min of manual review and editing.

10.
Cancer Epidemiol Biomarkers Prev ; 29(4): 787-795, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31988074

RESUMO

BACKGROUND: Cleveland, Ohio, is home to three major hospital systems serving approximately 80% of the Northeast Ohio population. The Cleveland Clinic, University Hospitals Health System, and MetroHealth are direct competitors for primary and specialty care, and patient overlap between these systems is high. Fragmentation of health data that exist in silos at these health systems produces an overestimation of disease burden due to double and sometimes triple counting of patients. As a result, longitudinal population-based studies across the Cleveland patient population are impeded unless accurate and actionable clinically derived health data sets can be created. METHODS: The Cleveland Institute for Computational Biology has developed the De-Duplicate and De-Identify Research Engine (DeDeRE) that, without any exchange of personal health identifiers (PHI) between health systems, will effectively de-duplicate the patients between one or more health entities. RESULTS: The immediate utility of this software for cancer epidemiology is the increased accuracy in measuring cancer burden and the potential to perform longitudinal studies with de-duplicated, de-identified data sets. CONCLUSIONS: The DeDeRE software developed and tested here accomplishes its goals without exposing PHIs using a state-of-the-art, trusted privacy preservation network enabled by a hash-based matching algorithm. IMPACT: This paper will guide the reader through the functions currently developed in DeDeRE and how a healthcare organization (HCO) employing the release version of this technology can begin sharing data with one or more additional HCOs in a collaborative and noncompetitive manner to create a regional population health resource for cancer researchers.See all articles in this CEBP Focus section, "Modernizing Population Science."


Assuntos
Conjuntos de Dados como Assunto , Troca de Informação em Saúde , Registros de Saúde Pessoal , Neoplasias/epidemiologia , Algoritmos , Cidades/epidemiologia , Confidencialidade , Humanos , Ohio , Software
11.
J Cataract Refract Surg ; 46(3): 355-359, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32050222

RESUMO

PURPOSE: To determine whether intracameral moxifloxacin 500 µg is noninferior to 250 µg for central endothelial cell loss (ECL) after phacoemulsification. SETTING: Aravind Eye Care System. DESIGN: Prospective masked randomized study. METHODS: Eyes with bilateral nuclear cataracts, central endothelial cell density (ECD) of more than 2000 cells/mm, and ECD not differing between eyes by more than 200 cells/mm underwent phacoemulsification at least 14 days apart. Intraoperatively, the first eye was randomized to receive either a 500 or 250 µg dose of moxifloxacin intracamerally and received the other dose for the second-eye surgery. Postoperative course was monitored at 1 day, 1 week, 1 month, and 3 months. Preoperative and 30-day and 90-day postoperative central ECD was determined by a reading center for a masked analysis of ECL at 3 months postoperatively. RESULTS: Fifty eyes of 25 patients (aged 48 to 69 years) underwent uneventful surgery and had normal postoperative courses. The point estimate (PE) and 95% CI for the mean difference in % ECL between the 500 µg and 250 µg doses at 3 months postoperatively was 0.8% (-5.8%, 7.4%). Upon identifying and removing 2 outliers, noninferiority was proven with a mean difference of the PE, -2.2% (CI, -6.5%, 2.1%). CONCLUSIONS: Clinical and corneal endothelial cell were comparable in this study population for the 250 µg and 500 µg doses of intracameral moxifloxacin. Both doses were well tolerated clinically, supporting the use of the higher dose for improved antimicrobial coverage for the prevention of postoperative endophthalmitis.


Assuntos
Antibacterianos/toxicidade , Endoftalmite/prevenção & controle , Endotélio Corneano/efeitos dos fármacos , Moxifloxacina/toxicidade , Facoemulsificação , Complicações Pós-Operatórias/prevenção & controle , Idoso , Câmara Anterior/efeitos dos fármacos , Antibacterianos/administração & dosagem , Antibioticoprofilaxia , Perda de Células Endoteliais da Córnea/induzido quimicamente , Perda de Células Endoteliais da Córnea/diagnóstico , Método Duplo-Cego , Feminino , Humanos , Implante de Lente Intraocular , Masculino , Pessoa de Meia-Idade , Moxifloxacina/administração & dosagem , Nível de Efeito Adverso não Observado , Estudos Prospectivos , Acuidade Visual
12.
Artigo em Inglês | MEDLINE | ID: mdl-31762537

RESUMO

Images of the endothelial cell layer of the cornea can be used to evaluate corneal health. Quantitative biomarkers extracted from these images such as cell density, coefficient of variation of cell area, and cell hexagonality are commonly used to evaluate the status of the endothelium. Currently, fully-automated endothelial image analysis systems in use often give inaccurate results, while semi-automated methods, requiring trained image analysis readers to identify cells manually, are both challenging and time-consuming. We are investigating two deep learning methods to automatically segment cells in such images. We compare the performance of two deep neural networks, namely U-Net and SegNet. To train and test the classifiers, a dataset of 130 images was collected, with expert reader annotated cell borders in each image. We applied standard training and testing techniques to evaluate pixel-wise segmentation performance, and report corresponding metrics such as the Dice and Jaccard coefficients. Visual evaluation of results showed that most pixel-wise errors in the U-Net were rather non-consequential. Results from the U-Net approach are being applied to create endothelial cell segmentations and quantify important morphological measurements for evaluating cornea health.

13.
Cornea ; 38(3): 325-331, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30614901

RESUMO

PURPOSE: To evaluate corneal endothelial cell density (ECD) and morphology 2 years after phacoemulsification in subjects from the COMPASS trial (ClinicalTrials.gov, NCT01085357) who had mild-to-moderate primary open-angle glaucoma and visually significant cataracts. METHODS: The central corneal endothelium was evaluated by serial specular microscopy at 0 to 24 months. ECD, coefficient of variation, and percentage of hexagonal cells were evaluated by a central image analysis reading center and central corneal thickness (CCT) was evaluated by ultrasound pachymetry. RESULTS: Of 131 subjects who underwent routine phacoemulsification, analyzable endothelial images at 24 months were available for 126 subjects (96.2%). Mean ± SD central ECD at baseline was 2453 ± 359 cells/mm, decreasing by 10% ± 14% to 2195 ± 517 cells/mm at 3 months (P < 0.001) but stabilizing thereafter with mean endothelial cell loss (ECL) from baseline to 24 months of 9% ± 13% (P < 0.001). Twelve (9.5%) and 10 (7.9%) subjects experienced >30% ECL at 12 and 24 months, respectively. Neither coefficient of variation nor percentage of hexagonal cells changed significantly from baseline at any time point. Mean CCT was similar at baseline (550 ± 35 µm) and at 12 months (551 ± 37 µm) and 24 months (555 ± 35 µm). Age was significantly associated with ECL after cataract surgery (P = 0.02), but baseline intraocular pressure, number of glaucoma medications, and CCT were not. Similar results were observed in patients who underwent CyPass micro-stent implantation accompanying phacoemulsification. CONCLUSIONS: Phacoemulsification in eyes with mild-to-moderate primary open-angle glaucoma results in early ECL, with ECD stabilizing after 3 months and no effect on other endothelial stress markers up to 2 years postoperatively.


Assuntos
Perda de Células Endoteliais da Córnea/patologia , Glaucoma de Ângulo Aberto/cirurgia , Implante de Lente Intraocular , Facoemulsificação/efeitos adversos , Idoso , Contagem de Células , Perda de Células Endoteliais da Córnea/etiologia , Paquimetria Corneana , Endotélio Corneano/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
14.
Cornea ; 38(4): 426-432, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30664048

RESUMO

PURPOSE: To evaluate agreement between eye banks (EBs) and a reading center on endothelial cell density (ECD) determinations in the Cornea Preservation Time Study. METHODS: The Cornea Image Analysis Reading Center (CIARC) performed variable frame image analysis on EB-obtained-preoperative central endothelial images (after lamellar dissection for Descemet stripping automated endothelial keratoplasty by the EBs or before shipping, if surgeon prepared) to determine ECD. The EBs performed their usual method of ECD determination. The CIARC and EBs also provided ECD determinations from screening central endothelial images taken by the EBs during donor evaluation. Two independent masked CIARC readers determined ECD with measurements averaged. RESULTS: The mean preoperative ECD was 15 cells/mm greater by the EBs than by CIARC (N = 1286, P < 0.001) with 95% limits of agreement of (-644, 675 cells/mm). The limits of agreement in preoperative ECD were wider in the After-Lamellar-Dissection Group (-687, 683 cells/mm) than in the Before Shipping Group [(-505, 633 cells/mm); P = 0.03]. The EBs-determined preoperative ECD was within 10% of the CIARC-determined ECD for 886 (69%) image sets, with 236 (18%) higher by >10% and 164 (13%) lower by >10%. Excellent agreement appeared between the EBs and CIARC when 100-300 cells could be analyzed in contrast to <100 cells (SD = 308 cells/mm vs. SD = 603 cells/mm; P < 0.001). CONCLUSIONS: The mean ECD by the EBs and CIARC were similar, but there was considerable variability between determinations for individual corneas. Agreement improved between the 2 measurements when more than 100 cells were able to be analyzed.


Assuntos
Contagem de Células/métodos , Perda de Células Endoteliais da Córnea/diagnóstico por imagem , Endotélio Corneano/citologia , Bancos de Olhos/estatística & dados numéricos , Processamento de Imagem Assistida por Computador , Adolescente , Adulto , Idoso , Criança , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior , Endotélio Corneano/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
15.
JAMA Ophthalmol ; 137(2): 185-193, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30422157

RESUMO

Importance: Determining factors associated with endothelial cell loss after Descemet stripping automated endothelial keratoplasty (DSAEK) could improve long-term graft survival. Objective: To evaluate the associations of donor, recipient, and operative factors with endothelial cell density (ECD) 3 years after DSAEK in the Cornea Preservation Time Study. Design, Setting, and Participants: This cohort study was a secondary analysis of data collected in a multicenter, double-masked, randomized clinical trial. Forty US clinical sites with 70 surgeons participated, with donor corneas provided by 23 US eye banks. Individuals undergoing DSAEK for Fuchs dystrophy or pseudophakic/aphakic corneal edema were included. Interventions: The DSAEK procedure, with random assignment of a donor cornea with a preservation time of 0 to 7 days or 8 to 14 days. Main Outcomes and Measures: Endothelial cell density at 3 years as determined by a reading center from eye bank and clinical specular or confocal central endothelial images. Results: The study included 1090 participants (median age, 70 years) with 1330 affected eyes (240 bilateral cases [22.0%]), who underwent DSAEK for Fuchs dystrophy (1255 eyes [94.4%]) or pseudophakic/aphakic corneal edema (PACE) (75 eyes [5.6%]). Of these, 801 eyes (60.2%) belonged to women and 1207 (90.8%) to white individuals. A total of 749 participants (913 eyes; 164 [21.9%] bilateral cases) had functioning grafts with acceptable endothelial images preoperatively and at 3 years postoperatively and were included in this analysis. Factors associated with a lower ECD at 3 years (estimated effect with 99% CI) in the final multivariable model included donors with diabetes (-103 [-196 to -9] cells/mm2), lower screening ECD (-234 [-331 to -137] per 500 cells/mm2), recipient diagnosis of PACE (-257 [-483 to -31] in cells/mm2), and operative complications (-324 [-516 to -133] in cells/mm2). Endothelial cell loss (ECL) from a preoperative measurement to a 3-year postoperative measurement was 47% (99% CI, 42%-52%) for participants receiving tissue from donors with diabetes vs 43% (99% CI, 39%-48%) without diabetes; it was 53% (99% CI, 44%-62%) for participants diagnosed with PACE vs 44% (99% CI, 39%-49%) for those diagnosed with Fuchs dystrophy, and 55% (99% CI, 48%-63%) in participants who experienced operative complications vs 44% (99% CI, 39%-48%) in those who did not. No other donor, recipient, or operative factors were significantly associated with 3-year ECD. Conclusions and Relevance: Donor diabetes, lower screening ECD, a PACE diagnosis in the recipient, and operative complications were associated with lower ECD at 3 years after DSAEK surgery and may be associated with long-term graft success. While causation cannot be inferred, further studies on the association of donor diabetes and PACE in recipients with lower 3-year ECD warrant further study.


Assuntos
Córnea , Perda de Células Endoteliais da Córnea/diagnóstico , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior , Preservação de Órgãos/métodos , Doadores de Tecidos , Transplantados , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Contagem de Células , Criança , Edema da Córnea/cirurgia , Método Duplo-Cego , Endotélio Corneano/patologia , Feminino , Distrofia Endotelial de Fuchs/cirurgia , Sobrevivência de Enxerto/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Estudos de Tempo e Movimento
16.
J Neurosci ; 27(32): 8496-504, 2007 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-17687027

RESUMO

Alzheimer's disease is late life dementia associated with significant neurodegeneration in both cortical and subcortical regions. During the approximately 10 year course of the disease, neurons are lost in a progressive pattern that is relatively consistent among individuals. One example of this is the progression of disease pathology found in both the neocortex and archicortex. In these structures, the earliest problems can be found in superficial cortical layers (II-IV), whereas later the disease advances to involve the deeper cortical layers (V-VI). It is unclear whether these apparent differences in sensitivity are intrinsic to the neurons or imposed by external factors such as the pattern of connections. We used beta-amyloid (Abeta) peptide treatment of cultured mouse neurons as our model system. We show first that, as in hippocampus, dissociated cultures of embryonic cortical neurons are biased toward the survival of cells that were finishing division in the ventricular zone at the time of harvest. Thus, embryonic day 13.5 (E13.5) cultures contain primarily deep-layer neurons whereas E16.5 cultures contain cells destined for upper layers. We use this cell-type specific segregation to our advantage and show, using both differences in gene expression profiles and Abeta survival curves, that deeper layer neurons are significantly more resistant to the toxic effects of Abeta than are cells from the more superficial strata. This suggests that an intrinsic underlying biology drives at least part of the AD progression pattern and that the time of harvest is a crucial variable in the interpretation of any cortical culture experiment.


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/fisiologia , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Peptídeos beta-Amiloides/toxicidade , Animais , Células Cultivadas , Córtex Cerebral/química , Progressão da Doença , Suscetibilidade a Doenças/metabolismo , Suscetibilidade a Doenças/patologia , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Gravidez
17.
Cornea ; 37(5): 596-601, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29384810

RESUMO

PURPOSE: The effects of repeated intravitreal aflibercept injection (IAI) on the corneal endothelium were studied in patients with unilateral neovascular age-related macular degeneration. METHODS: RE-VIEW was a phase 4, open-label, single-arm, multicenter study. Patients received IAI every 8 weeks after 3 monthly doses. Slit-lamp biomicroscopy was performed at all study visits. The central corneal endothelial health was evaluated by specular microscopy in the treated versus untreated fellow eyes at baseline and weeks 24 and 52. RESULTS: No slit-lamp abnormalities were noted in 154 enrolled patients (eyes). Baseline versus 52-week mean (±SD) endothelial morphometric values (n = 118) for the treated versus untreated fellow eyes were respectively as follows: endothelial cell density was 2410 ± 364 versus 2388 ± 384 cells/mm at baseline and remained unchanged at 2401 ± 353 versus 2376 ± 364 cells/mm at 52 weeks (P = 0.87); the coefficient of variation was 33.5 ± 4.4% versus 34.0 ± 5.0% at baseline and remained unchanged at 34.2 ± 4.7% versus 34.1 ± 4.9% at 52 weeks (P = 0.18); the percentage of hexagonal cells was 59.5 ± 5.8% versus 59.6 ± 6.4% at baseline and remained unchanged at 59.5 ± 6.0% versus 59.5 ± 5.8% at 52 weeks (P = 0.96). CONCLUSIONS: Repeated IAI for 52 weeks had no apparent corneal endothelial toxicity noted on specular microscopy in patients treated for neovascular age-related macular degeneration.


Assuntos
Inibidores da Angiogênese/administração & dosagem , Endotélio Corneano/efeitos dos fármacos , Degeneração Macular/tratamento farmacológico , Receptores de Fatores de Crescimento do Endotélio Vascular/administração & dosagem , Proteínas Recombinantes de Fusão/administração & dosagem , Idoso , Inibidores da Angiogênese/efeitos adversos , Contagem de Células , Endotélio Corneano/citologia , Feminino , Humanos , Injeções Intravítreas , Masculino , Proteínas Recombinantes de Fusão/efeitos adversos , Acuidade Visual
18.
Cornea ; 35(12): 1556-1561, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27741015

RESUMO

PURPOSE: To evaluate a single eye bank's measurement of endothelial cell density (ECD) of Descemet membrane endothelial keratoplasty (DMEK) grafts before and after preparation using 2 separate counting methods. METHODS: A series of 60 donor tissues were prepared for DMEK surgery. One to 4 specular images of the central endothelium were taken both before and after preparation, and ECDs were evaluated for a total of 345 unique images. Images were then masked and provided to the Cornea Image Analysis Reading Center (CIARC) for independent analysis. RESULTS: Before preparation, average eye bank-determined ECD with the center method was 2678 ± 259 cells/mm and was 2599 ± 280 cells/mm CIARC-determined by the variable frame method (P < 0.001, n = 176). After preparation, eye bank-determined ECD was 2719 ± 265 cells/mm and CIARC-determined ECD was 2615 ± 344 cells/mm (P < 0.001, n = 169). The difference in ECD before and after DMEK preparation was not found to be statistically significant when evaluated using either analysis method (P = 0.19; P = 0.64) before and after preparation, respectively. CONCLUSIONS: Although the absolute ECD value may differ by the analysis method statistically, pre- and post-DMEK preparation ECDs did not significantly change by either analysis method. Other methods such as vital staining to assess tissue damage after preparation in conjunction with specular microscopy are suggested.


Assuntos
Perda de Células Endoteliais da Córnea/diagnóstico , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior , Endotélio Corneano/patologia , Bancos de Olhos , Doadores de Tecidos , Coleta de Tecidos e Órgãos , Idoso , Contagem de Células , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Acuidade Visual
19.
JAMA Ophthalmol ; 131(5): 601-608, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23493999

RESUMO

IMPORTANCE: Endothelial morphometric measures have potential value in predicting graft failure after penetrating keratoplasty. OBJECTIVE: To determine whether preoperative and/or postoperative central morphometric measures (endothelial cell density [ECD], coefficient of variation [CV], and percentage of hexagonality [HEX]) and their postoperative changes are predictive of graft failure caused by endothelial decompensation after penetrating keratoplasty to treat a moderate-risk condition, principally Fuchs dystrophy or pseudophakic corneal edema. DESIGN: In a subset of Cornea Donor Study participants with graft failure, a central reading center determined preoperative and postoperative ECD, CV, and HEX from available central endothelial specular images. SETTING: Cornea Image Analysis Reading Center of the Specular Microscopy Ancillary Study. PARTICIPANTS: Eighteen patients with graft failure due to endothelial decompensation and 54 individuals matched for most donor and recipient measures at baseline whose grafts did not fail. MAIN OUTCOME MEASURE: Change in ECD, CV, and HEX values. RESULTS: Preoperative ECD was not associated with graft failure (P = .43); however, a lower ECD at 6 months was predictive of subsequent failure (P = .004). Coefficient of variation at 6 months was not associated with graft failure in univariate (P = .91) or multivariate (P = .79) analyses. We found a suggestive trend of higher graft failure with lower HEX values at 6 months (P = .02) but not at the established statistical significance (P < .01). The most recent CV or HEX values, as time-dependent variables, were not associated with graft failure (P = .26 and P = .81, respectively). Endothelial cell density values decreased during follow-up, whereas CV and HEX appear to fluctuate without an apparent trend. CONCLUSIONS AND RELEVANCE: Endothelial cell density at 6 months after penetrating keratoplasty is predictive of graft failure, whereas CV and HEX appear to fluctuate postoperatively, possibly indicating an unstable endothelial population in clear and failing grafts. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00006411.


Assuntos
Perda de Células Endoteliais da Córnea/diagnóstico , Endotélio Corneano/patologia , Rejeição de Enxerto/diagnóstico , Ceratoplastia Penetrante , Idoso , Contagem de Células , Forma Celular , Tamanho Celular , Edema da Córnea/cirurgia , Feminino , Distrofia Endotelial de Fuchs/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Doadores de Tecidos
20.
Cornea ; 29(5): 523-7, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20299973

RESUMO

PURPOSE: To assess the effect of incision width (5.0 and 3.2 mm) on graft survival and endothelial cell loss 6 months and 1 year after Descemet stripping automated endothelial keratoplasty (DSAEK). METHODS: One hundred sixty-seven subjects with endothelial decompensation from a moderate-risk condition (principally Fuchs dystrophy or pseudophakic corneal edema) underwent DSAEK by 2 experienced surgeons. The donor was folded over and inserted with single-point fixation forceps. This retrospective analysis assessed graft survival, complications, and endothelial cell loss, which was calculated from baseline donor and 6-month and 1-year postoperative central endothelial images evaluated by an independent specular microscopy reading center. RESULTS: No primary graft failures occurred in either group. One-year graft survival rates were comparable (98% vs 97%) in the 5.0- and 3.2-mm groups, respectively (P = 1.0). Complications included graft dislocation, graft rejection episodes, and elevated intraocular pressure and occurred at similar rates in both groups (P > or = 0.28). Pupillary block glaucoma did not occur in either group. Mean baseline donor endothelial cell density did not differ: 2782 cells per square millimeter in the 5.0-mm (n = 64) and 2784 cells per square millimeter in the 3.2-mm (n = 103) groups. Percent endothelial cell loss was 27% +/- 20% (n = 55) versus 40% +/- 22% (n = 71; 6 months) and 31% +/- 19% (n = 45) versus 44% +/- 22% (n = 62; 12 months) in the 5.0- and 3.2-mm incision groups, respectively (both P < 0.001). CONCLUSIONS: One year after DSAEK, overall graft success was comparable for the 2 groups; however, the 5.0-mm incision width resulted in substantially lower endothelial cell loss at 6 and 12 months.


Assuntos
Perda de Células Endoteliais da Córnea/etiologia , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior/métodos , Sobrevivência de Enxerto , Complicações Pós-Operatórias , Idoso , Contagem de Células , Edema da Córnea/cirurgia , Perda de Células Endoteliais da Córnea/diagnóstico , Endotélio Corneano/patologia , Feminino , Seguimentos , Distrofia Endotelial de Fuchs/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Doadores de Tecidos , Acuidade Visual/fisiologia
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