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1.
Ophthalmol Sci ; 4(5): 100470, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827487

RESUMO

Purpose: Automated machine learning (AutoML) has emerged as a novel tool for medical professionals lacking coding experience, enabling them to develop predictive models for treatment outcomes. This study evaluated the performance of AutoML tools in developing models predicting the success of pneumatic retinopexy (PR) in treatment of rhegmatogenous retinal detachment (RRD). These models were then compared with custom models created by machine learning (ML) experts. Design: Retrospective multicenter study. Participants: Five hundred and thirty nine consecutive patients with primary RRD that underwent PR by a vitreoretinal fellow at 6 training hospitals between 2002 and 2022. Methods: We used 2 AutoML platforms: MATLAB Classification Learner and Google Cloud AutoML. Additional models were developed by computer scientists. We included patient demographics and baseline characteristics, including lens and macula status, RRD size, number and location of breaks, presence of vitreous hemorrhage and lattice degeneration, and physicians' experience. The dataset was split into a training (n = 483) and test set (n = 56). The training set, with a 2:1 success-to-failure ratio, was used to train the MATLAB models. Because Google Cloud AutoML requires a minimum of 1000 samples, the training set was tripled to create a new set with 1449 datapoints. Additionally, balanced datasets with a 1:1 success-to-failure ratio were created using Python. Main Outcome Measures: Single-procedure anatomic success rate, as predicted by the ML models. F2 scores and area under the receiver operating curve (AUROC) were used as primary metrics to compare models. Results: The best performing AutoML model (F2 score: 0.85; AUROC: 0.90; MATLAB), showed comparable performance to the custom model (0.92, 0.86) when trained on the balanced datasets. However, training the AutoML model with imbalanced data yielded misleadingly high AUROC (0.81) despite low F2-score (0.2) and sensitivity (0.17). Conclusions: We demonstrated the feasibility of using AutoML as an accessible tool for medical professionals to develop models from clinical data. Such models can ultimately aid in the clinical decision-making, contributing to better patient outcomes. However, outcomes can be misleading or unreliable if used naively. Limitations exist, particularly if datasets contain missing variables or are highly imbalanced. Proper model selection and data preprocessing can improve the reliability of AutoML tools. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

3.
Clin Ophthalmol ; 16: 1383-1390, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35520109

RESUMO

Purpose: Selective laser trabeculoplasty is a safe and effective procedure for reducing IOP, but its mechanism of action is not fully elucidated. We evaluated the morphologic and cellular changes as well as DNA synthesis after SLT treatment of human trabecular meshwork (TM) tissue explants. Methods: Corneoscleral rim tissues that underwent SLT treatment were compared to control segments that had no laser treatment. Light microscopy (LM), transmission electron microscopy (TEM), and scanning electron microscopy (SEM) were used to assess cell morphology. The Click-iT 5-ethynyl-2'-deoxyuridine (EdU) imaging kit was used to compare DNA synthesis/cell proliferation with a confocal microscope. All tissues were assessed for vitality. Results: SLT treatment does not reveal notable cell damage in the juxtacanalicular (JCT) region, but mildly disrupts superficial trabecular beams and uveal TM, ablates TM endothelial cells from the undamaged beams as detected by both LM and TEM. This superficial destruction was not observed in some SLT treatment spots on higher magnification by SEM. SLT treatment increased mitotic activity and DNA synthesis near the lining of Schlemm's canal after several days. Conclusion: SLT treatment disrupts endothelial cells in the corneoscleral TM and causes superficial ultrastructural changes to the uveal TM. SLT treatment also shows a trend towards dynamic time-dependent changes in (DNA synthesis) with an increase in mitotic activity at 7 days cell proliferation.

4.
Case Rep Ophthalmol Med ; 2021: 6816195, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34956683

RESUMO

While plasmapheresis is well known to significantly improve both retinal findings and systemic manifestations associated with Waldenstrom macroglobulinemia, few reports exist documenting changes in optical coherence tomography angiography (OCT-A). The authors present a case of a patient with Waldenstrom macroglobulinemia who had resolution of white-centered peripheral retinal lesions and parafoveal outer nuclear layer hyperreflective material following plasmapheresis. Applying image analysis software to before and after OCT-A images, the authors were able to show an objective decrease in retinal capillary and large vessel density following plasmapheresis. This technique can be used to guide treatment and surveillance for patients with hyperviscosity-related retinopathy.

5.
Retin Cases Brief Rep ; 15(4): 431-435, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30086105

RESUMO

PURPOSE: To report a case of macular vortex vein imaged with indocyanine green angiography, spectral domain optical coherence tomography, and optical coherence tomography angiography. METHODS: Observational case report. RESULTS: A 51-year-old myopic man presented with the complaint of a floater in his left eye for the previous 2 weeks. His visual acuity was 20/25 in the right eye and 20/40 in the left eye. Biomicroscopy was normal. Retinoscopy revealed lattice degeneration and posterior vitreous detachment of both eyes with dilated submacular vasculature in the right eye and submacular hemorrhage in the left eye. Spectral domain optical coherence tomography demonstrated dilated vessels in the choroid of the right eye and a choroidal neovascular membrane in the left eye. Fluorescein angiography and indocyanine green angiography showed a macular vortex vein in the right eye. Optical coherence tomography angiography demonstrated normal vessel densities in the superficial and deep capillary plexuses. No abnormalities were detected in the outer retina or choriocapillaris. Optical coherence tomography angiography delineated the macular vortex vein with a relative flow void in the right eye. His vision remained stable in the right eye. CONCLUSION: Macular vortex veins may be a prominent, albeit rare, incidental finding in highly myopic eyes. Further studies with application of newer optical coherence tomography angiography modalities, such as swept-source optical coherence tomography angiography, are recommended to improve our understanding and monitoring of these structures.


Assuntos
Corioide , Miopia , Angiografia , Corioide/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Miopia/diagnóstico por imagem , Tomografia de Coerência Óptica
7.
Ophthalmol Retina ; 3(2): 140-145, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30931417

RESUMO

Objective: To evaluate the outcomes of patients undergoing pneumatic retinopexy (PR) performed by vitreoretinal fellows at 6 academic centers in the United States. Design: Retrospective, multicenter, consecutive case series. Participants: 483 patients with primary retinal detachments who underwent PR by 49 vitreoretinal fellows from 6 U.S. training sites between 2002 and 2016. Methods: We reviewed medical records of patients and recorded baseline clinical characteristics (age, sex, baseline visual acuity, lens status, presence of lattice degeneration, presence of vitreous hemorrhage, location of retinal breaks, macular status, and size of detachment), visual and anatomic outcomes at 3-months after PR, as well as training level and PR experience of the fellow at the time of the procedure. Main Outcome Measures: Single-procedure anatomic success and visual acuity at 3-months follow-up, and association with clinical and training-related factors. Results: Vitreoretinal fellows performed a variable number of PR, with a median of 7 cases per fellow (range 1-24). Single-procedure anatomic success was 66.8%, and mean LogMAR visual outcome was 0.43 (Snellen equivalent 20/54) at 3 months. Factors that were independently associated with single-procedure success include phakic lens status (P = 0.01), smaller size of retinal detachment (P = 0.02), and the fellow's procedure experience (P = 0.01). The only factor associated with worse visual outcome was baseline visual acuity (P < 0.001). Conclusion: Vitreoretinal fellows perform variably few pneumatic retinopexies but have outcomes comparable to reported rates by experienced specialists. Procedure experience of individual fellows may impact anatomic outcomes.


Assuntos
Procedimentos Cirúrgicos Oftalmológicos/métodos , Descolamento Retiniano/cirurgia , Idoso , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estados Unidos , Acuidade Visual
9.
BMJ Open Ophthalmol ; 4(1): e000187, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30729172

RESUMO

BACKGROUND/AIMS: Optical coherence tomography (OCT) has become standard of care in the diagnosis and management of a myriad of retinal and optic nerve pathology. Access to diagnostic equipment and skilled imaging personnel in the after-hours setting is often limited. We examined the utility and diagnostic indications for automated OCT in a high-volume after-hours clinic within an eye institute. METHODS: OCT images obtained over a period of 15 months were reviewed in the context of electronic patient records. Residents and fellows were surveyed regarding their experience with the OCT and its value in emergency patient management. RESULTS: 202 patients and 359 eyes were examined. Complaints prompting imaging included flashes/floaters, metamorphopsia, decreased vision and scotomas. Diagnoses included vascular occlusion, retinal detachment, macular hole, cystoid macular oedema and central serous retinopathy. Of the 25 residents and fellows surveyed, most agreed that the OCT that facilitated delivery of optimal urgent management. OCT also aided in the triage of patients to specialty clinics. CONCLUSION: Expanded access to automated OCT in the urgent care setting shows promise for improving the accuracy and timeliness of diagnosis, which can be critical for optimising patient outcomes. OCT also provides clear, immediate documentation of pathology for substantiating medical decision-making.

11.
Ocul Immunol Inflamm ; 24(5): 544-8, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26472486

RESUMO

PURPOSE: Progressive outer retinal necrosis (PORN) associated with varicella zoster virus (VZV) is usually diagnosed in HIV positive or immunosuppressed patients. We report two cases of immunocompetent patients with necrotizing viral retinitis found to have idiopathic CD4 lymphocytopenia. METHODS: Clinical presentation, examination, imaging, and laboratory testing of two patients with VZV retinitis are presented. RESULTS: An HIV negative patient with history of herpes zoster presented with rapid loss of vision and examination consistent with PORN. PCR testing confirmed VZV. Lymphocytopenia was noted with a CD4 count of 25/mm(3). A second HIV negative patient presented with blurred vision and lid swelling and was found to have peripheral VZV retinitis confirmed by PCR. Laboratory workup revealed lymphocytopenia with a CD4 count of 133/mm(3). CONCLUSIONS: VZV necrotizing retinitis classic for PORN can occur in HIV negative patients. Idiopathic CD4 lymphocytopenia should be considered healthy patients who develop ocular infections seen in the immunocompromised.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Herpes Zoster Oftálmico/virologia , Herpesvirus Humano 3/isolamento & purificação , Linfopenia/virologia , Síndrome de Necrose Retiniana Aguda/virologia , Aciclovir/análogos & derivados , Aciclovir/uso terapêutico , Adulto , Antivirais/uso terapêutico , Contagem de Linfócito CD4 , Angiofluoresceinografia , Soronegatividade para HIV , Herpes Zoster Oftálmico/diagnóstico , Herpes Zoster Oftálmico/tratamento farmacológico , Humanos , Linfopenia/diagnóstico , Linfopenia/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Síndrome de Necrose Retiniana Aguda/diagnóstico , Síndrome de Necrose Retiniana Aguda/tratamento farmacológico , Tomografia de Coerência Óptica , Valaciclovir , Valina/análogos & derivados , Valina/uso terapêutico , Vitrectomia
12.
J Neuroophthalmol ; 34(2): 149-50, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24135969

RESUMO

Intermittent Horner syndrome is uncommon in both the adult and pediatric population. We describe a case of a pediatric patient with an intermittent Horner syndrome. Infrared photography and videography were used to help establish the diagnosis.


Assuntos
Encéfalo/patologia , Síndrome de Horner/diagnóstico , Adolescente , Humanos , Angiografia por Ressonância Magnética , Imageamento por Ressonância Magnética , Masculino
13.
Ophthalmic Plast Reconstr Surg ; 29(6): e160-2, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23446300

RESUMO

Common variable immune deficiency (CVID) is characterized by reduced serum immune globulins and impaired or absent antibody responses. Patients become more susceptible to infections and to lymphoproliferation and granulomatous inflammation. Ophthalmic manifestations of CVID are rare. The authors describe a case of orbital follicular hyperplasia in a 15-year-old girl with CVID syndrome causing proptosis and exposure keratopathy.


Assuntos
Face/anormalidades , Síndromes de Imunodeficiência/complicações , Órbita/patologia , Doenças Orbitárias/etiologia , Adolescente , Exoftalmia/etiologia , Feminino , Humanos , Hiperplasia/etiologia , Doenças da Imunodeficiência Primária
15.
Invest Ophthalmol Vis Sci ; 50(8): 3771-7, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19168904

RESUMO

PURPOSE: SPARC is a matricellular protein that is highly expressed in remodeling tissues, including the trabecular meshwork and ciliary body. The hypothesis for the study was that SPARC contributes to the regulation of intraocular pressure (IOP). The IOPs of SPARC-null mice, their corresponding wild-type (WT), and heterozygous animals were compared. METHODS: Diurnal and nocturnal IOPs of C57Bl/6x129SvJ WT, SPARC-null, and heterozygous mice were measured. Fluorophotometric measurements were made to assess aqueous turnover. Central corneal thickness (CCT) was measured using histology, ultrasound biomicroscopy, and optical coherence tomography. Iridocorneal angles were examined using light microscopy (LM). RESULTS: During the day, the mean IOP of SPARC-null mice (n = 142, 16.9 +/- 2.4 mm Hg) was lower than that of both WT mice (n = 104, 19.9 +/- 2.9 mm Hg; P < 10(-12)), and heterozygotes (n = 38, 19.3 +/- 2.5 mm Hg; P < 10(-4)). At night, SPARC-null mice also exhibited a blunted increase in IOP in comparison to WT and heterozygous mice. CCTs were not significantly different between WT and SPARC-null mice. Heterozygous mice tended to have thicker corneas (3.4%). Fluorophotometric measurements suggest that aqueous turnover rates in SPARC-null mice are equal to if not greater than rates in WT mice. LM of the SPARC-null iridocorneal angle revealed morphology that is indistinguishable from WT. CONCLUSIONS: SPARC-null mice have lower IOPs than do their WT counterparts with equal CCTs. The rate of aqueous turnover suggests that the mechanism is enhanced outflow resistance.


Assuntos
Humor Aquoso/metabolismo , Pressão Intraocular/fisiologia , Osteonectina/fisiologia , Animais , Segmento Anterior do Olho/citologia , Ritmo Circadiano , Córnea/diagnóstico por imagem , Feminino , Fluorofotometria , Deleção de Genes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Acústica , Tomografia de Coerência Óptica , Tonometria Ocular
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