Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
1.
Transl Vis Sci Technol ; 12(11): 5, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37917086

RESUMEN

Purpose: Predict central 10° global and local visual field (VF) measurements from macular optical coherence tomography (OCT) volume scans with deep learning (DL). Methods: This study included 1121 OCT volume scans and 10-2 VFs from 289 eyes (257 patients). Macular scans were used to estimate 10-2 VF mean deviation (MD), threshold sensitivities (TS), and total deviation (TD) values at 68 locations. A three-dimensional (3D) convolutional neural network based on the 3D DenseNet121 architecture was used for prediction. We compared DL predictions to those from baseline linear models. We carried out 10-fold stratified cross-validation to optimize generalizability. The performance of the DL and baseline models was compared based on correlations between ground truth and predicted VF measures and mean absolute error (MAE; ground truth - predicted values). Results: Average (SD) MD was -9.3 (7.7) dB. Average (SD) correlations between predicted and ground truth MD and MD MAE were 0.74 (0.09) and 3.5 (0.4) dB, respectively. Estimation accuracy deteriorated with worsening MD. Average (SD) Pearson correlations between predicted and ground truth TS and MAEs for DL and baseline model were 0.71 (0.05) and 0.52 (0.05) (P < 0.001) and 6.5 (0.6) and 7.5 (0.5) dB (P < 0.001), respectively. For TD, correlation (SD) and MAE (SD) for DL and baseline models were 0.69 (0.02) and 0.48 (0.05) (P < 0.001) and 6.1 (0.5) and 7.8 (0.5) dB (P < 0.001), respectively. Conclusions: Macular OCT volume scans can be used to predict global central VF parameters with clinically relevant accuracy. Translational Relevance: Macular OCT imaging may be used to confirm and supplement central VF findings using deep learning.


Asunto(s)
Aprendizaje Profundo , Tomografía de Coherencia Óptica , Humanos , Campos Visuales , Ojo , Redes Neurales de la Computación
2.
Am J Ophthalmol ; 249: 12-20, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36516918

RESUMEN

PURPOSE: We compared ganglion cell layer (GCL) and inner plexiform layer (IPL) rates of change (RoC) in patients with glaucoma suspect (GS) and established glaucoma (EG) to test the hypothesis that IPL thickness changes would occur earlier than GCL changes in eyes with early damage. DESIGN: Prospective, cohort study. METHODS: A total of 64 GS eyes (46 patients) and 112 EG eyes (112 patients) with ≥2 years of follow-up and ≥3 macular optical coherence tomography scans were included. GCL and IPL superpixel thickness measurements were exported. A Bayesian hierarchical model with random intercepts/slopes and random residual variances was fitted to estimate RoC in individual superpixels. Normalized RoC and proportions of superpixels with significantly negative and positive GCL and IPL RoC were compared within the groups. RESULTS: The average (SD) follow-up time and number of scans were 3.5 (0.7) years and 4.2 (1.0), respectively, in the GS group and 3.6 (0.4) years and 7.3 (1.1) in the EG group. Mean (SD) normalized RoC was faster for GCL than IPL (-0.69 [0.05] vs -0.33 [0.04]) in the GS group, whereas it was faster for IPL (-0.47 [0.03] vs -0.28 [0.02]) in EG eyes. GCL RoC were significantly negative in 24 of 36 superpixels compared with 8 of 36 for IPL (P < .001) in GS eyes. In the EG group, 23 of 36 superpixels had significant negative IPL RoC compared with 13 of 36 superpixels for GCL (P = .006). CONCLUSIONS: GCL thickness is more likely to demonstrate change over time compared with IPL in glaucoma suspects. There is no evidence of preferential IPL thinning in eyes with suspected early glaucoma damage.


Asunto(s)
Glaucoma , Células Ganglionares de la Retina , Humanos , Estudios Prospectivos , Teorema de Bayes , Estudios de Cohortes , Presión Intraocular , Fibras Nerviosas , Estudios Transversales , Glaucoma/diagnóstico , Tomografía de Coherencia Óptica/métodos
3.
Ophthalmol Glaucoma ; 6(1): 68-77, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35750324

RESUMEN

OBJECTIVE: To investigate the confounding effect of nonexudative age-related macular degeneration (AMD), specifically drusen and outer retinal atrophy, on the architecture and automated segmentation of the inner retinal layers as measured with OCT. DESIGN: Observational cross-sectional study. SUBJECTS: Two hundred sixty-three consecutive eyes with nonexudative AMD were identified through a retrospective chart review. Exclusion criteria were a diagnosis of glaucoma or glaucoma suspect, other retinal pathology affecting the macula, axial length > 26.5 mm or spherical equivalent less than -6 diopters, any other optic nerve or neurologic disorders, or poor image quality. METHODS: Drusen were automatically segmented on macular OCT B-scans with a publicly available and validated deep learning approach. Automated segmentation of the inner plexiform layer (IPL)/inner nuclear layer (INL) boundary was carried out with the device's proprietary software. MAIN OUTCOME MEASURES: Quality of segmentation of the IPL/INL boundary as a function of drusen size and presence of inner retinal layer displacement in the area of macular pathology (drusen or atrophy). RESULTS: One hundred twenty-five eyes (65 patients) met the inclusion criteria. Drusen size varied between 16 and 272 µm (mean, 118 µm). Automated segmentation had a 22% chance of failure if the drusen height was between 145 and 185 µm and was most likely to fail with drusen heights above 185 µm. When drusen height was normalized by total retinal thickness, segmentation failed 36% of the time when the drusen to total retinal thickness ratio was 0.45 or above. Images were likely to show displacement of inner retinal layers with drusen heights above 176 µm and a normalized drusen height ratio of 0.5 or higher. Eighty-seven percent of images with outer retinal atrophy displayed incorrect segmentation. CONCLUSIONS: Outer retinal diseases can alter the retinal topography and affect the segmentation accuracy of the inner retinal layers. Large drusen may cause segmentation error and compression of the inner macular layers. Geographic atrophy confounds automated segmentation in a high proportion of eyes. Clinicians should be cognizant of the effects of outer retinal disease on the inner retinal layer measurements when interpreting the results of macular OCT imaging in patients with glaucoma.


Asunto(s)
Glaucoma , Mácula Lútea , Degeneración Macular , Enfermedades de la Retina , Humanos , Estudios Retrospectivos , Tomografía de Coherencia Óptica/métodos , Degeneración Macular/diagnóstico , Glaucoma/diagnóstico , Glaucoma/patología , Mácula Lútea/patología
4.
Am J Rhinol Allergy ; 36(6): 827-834, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35915990

RESUMEN

OBJECTIVES: To examine the epidemiology, subtypes, trends over time, and predictive factors for recurrence and malignant transformation of sinonasal papillomas. METHODS: A retrospective chart review of 118 patients with sinonasal papillomas from 2009 to 2019 was conducted at the University of California, Los Angeles. This study is a follow-up to a previously published study from 2000 to 2009 at the same academic center. RESULTS: The mean age was at presentation was 58.5 years, with a 2:1 male to female ratio, and average follow-up of 30.1 months. The rate of recurrence after complete resection was 19% with an average of 32.6 months to recurrence. The time to recurrence followed a bimodal distribution with 57% of cases recurring within 24 months (mean = 10) and 43% from 40 to 103 months (mean = 61). The proportion of the inverted papillomas rose from 38% in 2000-2004 to 89.6% in 2015-2019. Patients presenting at a younger age had a higher chance of recurrence (mean age 52 with recurrence vs. 61 without recurrence). Age did not correlate with histopathologic transformation in surgical pathology. Furthermore, histopathological transformation did not raise the chance of recurrence. Smoking, alcohol use, chronic rhinosinusitis, and allergic rhinitis were not associated with any of the outcome measures in this study. The most significant factor predicting recurrence, beside age at presentation, was the history of two or more prior sinus surgeries for papillomas or other reasons (OR = 3.52 and 5.81). CONCLUSION: This study explored the features of sinonasal papillomas as well as the risk factors for recurrence and transformation. Younger age at presentation and two or more prior surgeries for papillomas were associated with recurrence. Time to recurrence followed a bimodal distribution, with late recurrences happenning from 40 to 103 months after surgery, emphasizing the importance of long-term follow-up for timely resection of tumors and prevention of malignancy.


Asunto(s)
Neoplasias Nasales , Papiloma Invertido , Neoplasias de los Senos Paranasales , Transformación Celular Neoplásica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/epidemiología , Neoplasias Nasales/epidemiología , Neoplasias Nasales/patología , Neoplasias Nasales/cirugía , Papiloma Invertido/epidemiología , Papiloma Invertido/patología , Papiloma Invertido/cirugía , Neoplasias de los Senos Paranasales/epidemiología , Neoplasias de los Senos Paranasales/patología , Neoplasias de los Senos Paranasales/cirugía , Estudios Retrospectivos
5.
Ophthalmic Surg Lasers Imaging Retina ; 53(7): 398-402, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35858232

RESUMEN

Malignant infantile osteopetrosis is a rare inherited disorder with neurological complications and a shortened life expectancy. Vision loss is typically attributed to osseous compression of the optic nerves at the level of the optic canal. Fundus imaging is reported, as well as the first optical coherence tomography and optical coherence tomography angiography in this rare condition. Imaging revealed optic nerve pallor, subfoveal ellipsoid zone disruption, and an enlarged foveal avascular zone. These results provide insight regarding other potential mechanisms of vision loss in these patients. [Ophthalmic Surg Lasers Imaging Retina 2022; 53:398-402.].


Asunto(s)
Osteopetrosis , Tomografía de Coherencia Óptica , Angiografía con Fluoresceína/métodos , Fóvea Central/patología , Fondo de Ojo , Humanos , Osteopetrosis/diagnóstico , Osteopetrosis/patología , Tomografía de Coherencia Óptica/métodos , Trastornos de la Visión/patología
6.
Psychoneuroendocrinology ; 123: 105039, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33161257

RESUMEN

Autism spectrum disorder (ASD) has been associated with imbalance between excitatory and inhibitory (E/I) neurotransmission systems, as well as with neuroinflammation. Sitting at the crossroads between E/I imbalance and neuroinflammation is a class of endogenous hormones known as neurosteroids. Current literature points to dysregulated steroid metabolism and atypical neurosteroid levels in ASD as early as in utero. However, due to the complexity of neurosteroid metabolomics, including possible sex differences, the impact of neurosteroids on ASD symptomatology remains unclear. In this study, we assessed neurosteroid levels and ASD symptom severity of 21 males with ASD and 20 full-scale-IQ-matched typically developing (TD) males, all aged 18-39. Using liquid chromatography-tandem mass spectrometry, concentrations of allopregnanolone, cortisol, dehydroepiandrosterone, progesterone, and testosterone were measured in saliva and serum. With the exception of cortisol's, all neurosteroids' concentrations were found to have ASD vs. TD group differences in distribution, where one group was normally distributed and the other non-normally distributed. Serum allopregnanolone levels in males with ASD were found to negatively correlate with clinician-rated measures of restricted and repetitive behavior measures (ADOS-2 RRB and ADI-R RRSB domain scores). Additionally, lower serum allopregnanolone levels were found to predict more negative camouflaging scores, which represent greater differences in self- and clinician-rated symptom severity, of both ASD symptomatology overall and repetitive behaviors in particular. Taken together, our findings demonstrate that in adult males with ASD, decreased serum allopregnanolone levels are associated with more severe restricted and repetitive behaviors and with less insight into the severity of these behaviors.


Asunto(s)
Trastorno del Espectro Autista , Pregnanolona , Adulto , Trastorno del Espectro Autista/sangre , Trastorno del Espectro Autista/psicología , Humanos , Masculino , Pregnanolona/sangre
7.
Int J Pediatr Otorhinolaryngol ; 136: 110141, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32554136

RESUMEN

BACKGROUND: In the last few decades, the increased survival of premature infants and critically ill children have led to the increased frequency and complexity of pediatric airway procedures. Minimizing readmission rates following these procedures is important to maximize health outcomes and cost effectiveness. This study examines the incidence, reasons, and risk factors for hospital readmissions following pediatric airway surgeries in a large, nationally representative sample. METHODS: Pediatric airway surgeries performed across 22 states in 2014 were identified using data from the Nationwide Readmissions Database (NRD). Airway surgeries were identified and categorized using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes into the following categories: tracheostomy, repair of larynx, repair of trachea, laryngeal excision, tracheal excision, bronchoscopy, laryngoscopy, laryngotracheal diagnostic procedures, other operations on larynx, and other operations on trachea. Univariate and multivariate analyses were used to identify factors significantly correlated with readmissions. RESULTS: 10,289 pediatric airway procedures over 7120 visits were identified. 954 readmissions were identified for an overall readmission rate of 13.4%. 613 of these readmissions were related to the initial procedure, yielding a relevant readmission rate of 8.6%. On univariate analysis, factors that varied significantly with readmission rates included number of diagnoses on record (OR 1.06), number of chronic conditions (OR 1.18), number of procedures (OR 1.07), public insurance status (OR 1.39), bottom quartile median household income in patient zip code (OR 1.29), teaching hospital status (OR 1.60), and chronic perinatal respiratory disease (OR 1.45). On multivariate analysis, significant predictors included number of diagnoses (OR 1.02), number of chronic conditions (OR 1.13), and bottom quartile median household income in patient zip code (OR 1.20). The most common categories for readmission were respiratory distress (36%), infection (24%), and pneumonia (14%). The top overall individual reasons for readmission were stenosis of larynx (7.3%) and pneumonia (5.9%). CONCLUSIONS: Pediatric airway surgeries have relatively high rates of readmission. Strategies to reduce readmissions should involve addressing health disparities and employing a multidisciplinary approach to improve care for medically complex patients.


Asunto(s)
Broncoscopía , Procedimientos Quirúrgicos Otorrinolaringológicos , Readmisión del Paciente/estadística & datos numéricos , Complicaciones Posoperatorias/etiología , Enfermedades Respiratorias/cirugía , Adolescente , Niño , Preescolar , Bases de Datos Factuales , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/terapia , Estudios Retrospectivos , Factores de Riesgo , Estados Unidos
8.
Nat Commun ; 8: 15269, 2017 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-28524850

RESUMEN

Fluorescence imaging in the second near-infrared window (NIR-II) allows visualization of deep anatomical features with an unprecedented degree of clarity. NIR-II fluorophores draw from a broad spectrum of materials spanning semiconducting nanomaterials to organic molecular dyes, yet unfortunately all water-soluble organic molecules with >1,000 nm emission suffer from low quantum yields that have limited temporal resolution and penetration depth. Here, we report tailoring the supramolecular assemblies of protein complexes with a sulfonated NIR-II organic dye (CH-4T) to produce a brilliant 110-fold increase in fluorescence, resulting in the highest quantum yield molecular fluorophore thus far. The bright molecular complex allowed for the fastest video-rate imaging in the second NIR window with ∼50-fold reduced exposure times at a fast 50 frames-per-second (FPS) capable of resolving mouse cardiac cycles. In addition, we demonstrate that the NIR-II molecular complexes are superior to clinically approved ICG for lymph node imaging deep within the mouse body.


Asunto(s)
Colorantes Fluorescentes/química , Ionóforos/química , Imagen Óptica , Espectroscopía Infrarroja Corta , Animales , Femenino , Fluorescencia , Ganglios Linfáticos/patología , Ratones , Ratones Desnudos , Nanoestructuras/química , Nanotubos de Carbono/química , Compuestos Orgánicos/química , Teoría Cuántica , Semiconductores , Grabación en Video
9.
Small ; 11(47): 6325-30, 2015 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-26529611

RESUMEN

Postsynthetic single-walled carbon nanotube (SWCNT) sorting methods such as density gradient ultracentrifugation, gel chromatography, and electrophoresis have all been inspired by established biochemistry separation techniques designed to separate subcellular components. Biochemistry separation techniques have been refined to the degree that parameters such as pH, salt concentration, and temperature are necessary for a successful separation, yet these conditions are only now being applied to SWCNT separation methodologies. Slight changes in pH produce radically different behaviors of SWCNTs inside a density gradient, allowing for the facile separation of ultrahigh purity (6,4) SWCNTs from as-synthesized carbon nanotubes. The (6,4) SWCNTs are novel fluorophores emitting below ≈900 nm and can be easily detected with conventional silicon-based charge-coupled device detectors without the need for specialized InGaAs cameras. The (6,4) SWCNTs are used to demonstrate their potential as a clinically relevant NIR-I fluorescence stain for the immunohistochemical staining of cells and cancer tissue sections displaying high endothelial growth factor receptor levels.


Asunto(s)
Imagenología Tridimensional/instrumentación , Imagenología Tridimensional/métodos , Nanotubos de Carbono/química , Silicio/química , Línea Celular Tumoral , Fluorescencia , Humanos , Concentración de Iones de Hidrógeno , Imagen Molecular , Ultracentrifugación
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...