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1.
Clin Ophthalmol ; 18: 943-950, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38560333

RESUMO

Purpose: Achieving competency in cataract surgery is an essential component of ophthalmology residency training. Video-based analysis of surgery can change training through its objective, reliable, and timely assessment of resident performance. Methods: Using the Image Labeler application in MATLAB, the capsulorrhexis step of 208 surgical videos, recorded at the University of Michigan, was annotated for subjective and objective analysis. Two expert surgeons graded the creation of the capsulorrhexis based on the International Council of Ophthalmology's Ophthalmology Surgical Competency Assessment Rubric:Phacoemulsification (ICO-OSCAR:phaco) rating scale and a custom rubric (eccentricity, roundness, size, centration) that focuses on the objective aspects of this step. The annotated rhexis frames were run through an automated analysis to obtain objective scores for these components. The subjective scores were compared using both intra and inter-rater analyses to assess the consistency of a human-graded scale. The subjective and objective scores were compared using intraclass correlation methods to determine relative agreement. Results: All rhexes were graded as 4/5 or 5/5 by both raters for both items 4 and 5 of the ICO-OSCAR:phaco rating scale. Only roundness scores were statistically different between the subjective graders (mean difference = -0.149, p-value = 0.0023). Subjective scores were highly correlated for all components (>0.6). Correlations between objective and subjective scores were low (0.09 to 0.39). Conclusion: Video-based analysis of cataract surgery presents significant opportunities, including the ability to asynchronously evaluate performance and provide longitudinal assessment. Subjective scoring between two raters was moderately correlated for each component.

2.
IEEE J Biomed Health Inform ; 28(3): 1599-1610, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38127596

RESUMO

Cataract surgery remains the only definitive treatment for visually significant cataracts, which are a major cause of preventable blindness worldwide. Successful performance of cataract surgery relies on stable dilation of the pupil. Automated pupil segmentation from surgical videos can assist surgeons in detecting risk factors for pupillary instability prior to the development of surgical complications. However, surgical illumination variations, surgical instrument obstruction, and lens material hydration during cataract surgery can limit pupil segmentation accuracy. To address these problems, we propose a novel method named adaptive wavelet tensor feature extraction (AWTFE). AWTFE is designed to enhance the accuracy of deep learning-powered pupil recognition systems. First, we represent the correlations among spatial information, color channels, and wavelet subbands by constructing a third-order tensor. We then utilize higher-order singular value decomposition to eliminate redundant information adaptively and estimate pupil feature information. We evaluated the proposed method by conducting experiments with state-of-the-art deep learning segmentation models on our BigCat dataset consisting of 5,700 annotated intraoperative images from 190 cataract surgeries and a public CaDIS dataset. The experimental results reveal that the AWTFE method effectively identifies features relevant to the pupil region and improved the overall performance of segmentation models by up to 2.26% (BigCat) and 3.31% (CaDIS). Incorporation of the AWTFE method led to statistically significant improvements in segmentation performance (P < 1.29 × 10-10 for each model) and yielded the highest-performing model overall (Dice coefficients of 94.74% and 96.71% for the BigCat and CaDIS datasets, respectively). In performance comparisons, the AWTFE consistently outperformed other feature extraction methods in enhancing model performance. In addition, the proposed AWTFE method significantly improved pupil recognition performance by up to 2.87% in particularly challenging phases of cataract surgery.


Assuntos
Extração de Catarata , Catarata , Humanos , Pupila , Extração de Catarata/métodos , Catarata/diagnóstico por imagem , Processamento de Imagem Assistida por Computador
3.
Cornea ; 39(10): 1243-1246, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32898354

RESUMO

PURPOSE: To evaluate the recipient factors associated with graft detachment in the subsequent eye of patients who underwent sequential Descemet membrane endothelial keratoplasty (DMEK). METHODS: A retrospective, consecutive case series with 158 eyes of 79 patients who underwent DMEK surgeries in both eyes between October 2013 and April 2019 for treatment of Fuchs endothelial dystrophy. The main outcome measure was the presence of graft detachment (any amount of detachment) at postoperative 1 week in the subsequent eye. Preoperative, intraoperative, and postoperative factors were evaluated for association with graft detachment. RESULTS: Of 79 patients (158 eyes) with a mean follow-up of 11.7 ± 8.4 months, 18 patients (36 eyes) developed graft detachment in both eyes 1 week postoperatively. The risk of detachment in the subsequent eye was increased when the first eye had any amount of detachment [odds ratio = 2.8; 95% confidence interval (CI) = 1.1-7.3; P = 0.037]. When the first eye had a clinically significant detachment (>30% detached), the risk of detachment occurring in the subsequent eye was greater (odds ratio = 15.7; 95% CI = 1.8-134.5; P = 0.012). This risk of graft detachment in the subsequent eye increased 33% for every 5% increase in the detachment percentage in the first eye (odds ratio = 1.3; 95% CI = 1.1-1.6; P = 0.008). CONCLUSIONS: The presence of graft detachment after DMEK increases the risk of graft detachment in subsequent DMEK in the contralateral eye. Modification in perioperative care and surgical technique in the contralateral eye, such as a larger gas bubble, use of SF6 20%, and combining cataract surgery, may be needed when graft detachment occurs after DMEK in the first eye.


Assuntos
Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior , Distrofia Endotelial de Fuchs/cirurgia , Rejeição de Enxerto/etiologia , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos , Fatores de Risco , Transplantados , Acuidade Visual/fisiologia
4.
Ocul Immunol Inflamm ; 22(1): 15-22, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23730797

RESUMO

PURPOSE: To investigate whether lacrimal gland uptake on (67)Ga-gallium citrate scintigraphy correlates with histopathologic evidence of sarcoidosis. METHODS: A retrospective, pilot study of 31 patients with suspected sarcoidosis who underwent gallium scintigraphy and lacrimal gland biopsy. Lacrimal gland gallium uptake was assessed by subjective visual scoring (SVS) and lacrimal uptake ratio (LUR). RESULTS: Eleven (36%) patients had lacrimal gland biopsies containing noncaseating granulomas. A statistically significant correlation was found between lacrimal gland gallium uptake and biopsy positivity using SVS (p = 0.03) or LUR (p = 0.01). Using SVS, biopsy positivity rate increased from 0 to 50% in patients with mild to intense uptake. Using LUR, biopsy positivity rate increased linearly as the ratio increased from 13% (LUR < 4) to 100% (LUR > 8). CONCLUSIONS: Lacrimal biopsy positivity rate significantly correlated with gallium uptake on scintigraphy. Both SVS and LUR methods appear to correlate with histologic results and may potentially aid in patient selection for biopsy.


Assuntos
Citratos , Gálio , Doenças do Aparelho Lacrimal/diagnóstico por imagem , Compostos Radiofarmacêuticos , Sarcoidose/diagnóstico por imagem , Adolescente , Adulto , Idoso , Biópsia , Criança , Feminino , Radioisótopos de Gálio , Humanos , Doenças do Aparelho Lacrimal/patologia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Cintilografia , Estudos Retrospectivos , Sarcoidose/patologia , Sensibilidade e Especificidade , Adulto Jovem
5.
Ocul Immunol Inflamm ; 16(1): 25-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18379938

RESUMO

PURPOSE: To report a case where combined whole-body Fluorine-18 fluorodeoxyglucose (FDG) PET-CT scanning was used to aid in the diagnosis of a patient with occult sarcoidosis. DESIGN: Case report. METHODS: FDG PET-CT scanning was performed in a patient who presented with persistent bilateral panuveitis after cataract surgery and had undergone an extensive negative workup. RESULTS: FDG PET-CT scanning demonstrated extensive mediastinal adenopathy. Biopsy showed a non-caseating granuloma with associated giant cell formation consistent with a diagnosis of sarcoidosis. CONCLUSIONS: FDG PET-CT scanning generates tomographic scans with excellent sensitivity, spatial resolution, and anatomical landmark identification and may be useful in the workup of idiopathic uveitis.


Assuntos
Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Sarcoidose/diagnóstico , Tomografia Computadorizada por Raios X , Idoso , Extração de Catarata , Feminino , Humanos , Complicações Pós-Operatórias/etiologia , Sarcoidose/complicações , Uveíte/etiologia
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