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1.
Indian J Ophthalmol ; 70(5): 1617-1625, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35502038

RESUMEN

Purpose: Remnant lens epithelial cells (LECs) within the capsular bag (CB) undergo epithelial-to-mesenchymal transition (EMT) and acquire a myofibroblast phenotype, depositing extracellular matrix (ECM) components, leading to posterior capsular opacification (PCO). This study histopathologically analyzes the LEC-to-myofibroblast transition and de novo ECM component deposition (i.e., smooth muscle actin (SMA) and fibronectin (FN) expression) and determines the intraocular lens (IOL) and patient factors associated with these changes. Methods: In total, 190 CBs with IOLs were removed from donor eyes. Digital images were obtained, and PCO was graded using published software (ADOS, Medical Parachute). Automated immunohistochemistry was performed using anti-SMA to detect EMT and anti-FN to document ECM remodeling. Slides were digitized and analyzed using the Positive Pixel Count v9 algorithm. Linear regression and Poisson regression were performed (P < 0.05). Results: SMA positive expression decreased as the time of IOL implantation increased (P < 0.0001). Positivity of SMA and FN demonstrated a positive correlation (P = 0.0002). Controlling for confounding factors in Poisson regression, hydrophobic and hydrophilic materials showed higher FN and SMA expression when compared to silicone material lenses (FN; P = 0.018; P < 0.0001, SMA; P = 0.001; P = 0.003, respectively). The square optic design had 29% higher SMA positivity compared to the opti-edge design (P = 0.042). One-piece haptic lenses had higher SMA expression compared to three-piece haptic (P = 0.042). A higher risk of expression of SMA and FN was seen in patients with a history of smoking, hypertension, and glaucoma (P < 0.05). Conclusion: This study demonstrated that SMA and FN expression is different according to IOL design and patient factors, thus indicating that LEC changes depend on lens biocompatibility. Therefore, by analyzing the histopathological composition of PCO by using LECs, further insight into the characteristics of IOLs that are important for biocompatibility can be ascertained.


Asunto(s)
Opacificación Capsular , Cristalino , Lentes Intraoculares , Opacificación Capsular/diagnóstico , Opacificación Capsular/etiología , Células Epiteliales/metabolismo , Humanos , Cristalino/patología , Lentes Intraoculares/efectos adversos , Programas Informáticos
2.
Can J Ophthalmol ; 55(5): 437-444, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32585141

RESUMEN

OBJECTIVE: Patients have shown a lowering of intraocular pressure (IOP) after cataract surgery. Histopathology studies have reported trabecular meshwork (TM) changes in pseudophakic eyes with posterior chamber intraocular lens (PCIOL) and have eluded to the mechanisms for IOP decrease. Unlike PCIOLs, TM histopathology changes after implantation of an anterior chamber intraocular lens (ACIOL) have not been studied, to our knowledge. Therefore, this study aims to examine the histopathological changes in both the TM and corneal endothelium among donor eyes with ACIOL, PCIOL, and phakic eyes. METHODS: Forty fixed postmortem donor eyes were obtained, sectioned, and embedded. Slides were stained with Masson's trichrome and CD31 vascular endothelial antibody, and further digitalized. Customized Medical Parachute TMAN software quantified the cellular components, the trabecular extracellular matrix (ECM), ECM fibrosis, and trabecular area. Schlemm's canal and corneal endothelium were quantified across the ACIOL, PCIOL, and phakic groups. RESULTS: Cellular area component of the TM was lower in the ACIOLs and PCIOLs than in phakic eyes, but statistically significant only between PCIOL and phakic eyes (p = 0.0023). ECM area component, TM fibrosis score and TM lamellae area, ciliary process fibrosis, and CD31 expression in Schlemm's canal showed no differences (p = 0.40, 0.99, 0.10, 0.83, 0.45). Significantly lower corneal endothelial cells were seen in ACIOLs compared with both PCIOLs and phakic eyes (p = 0.0002). CONCLUSIONS: ACIOLs and PCIOLs in our sample group showed that there is loss of cellular components in the TM compared with the phakic eyes, with PCIOLs displaying the least amount of TM cells statistically, in this cohort. The ACIOLs led to a greater loss of corneal endothelial cells than both PCIOLs and phakic eyes after cataract surgery. The endothelial cells in Schlemm's canal did not seem to be affected by the IOL placements. Therefore, this study illustrates that there are histopathological differences seen with the placements of ACIOLs in both TM and cornea.


Asunto(s)
Células Endoteliales , Lentes Intraoculares , Cámara Anterior , Humanos , Implantación de Lentes Intraoculares , Esclerótica , Malla Trabecular
3.
Curr Eye Res ; 43(11): 1362-1368, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30009642

RESUMEN

Purpose/aim: Posterior capsular opacification (PCO) is the leading complication following cataract surgery. However, PCO grading methods vary between studies and rely on subjective scoring methods; hence, they are prone to error. Therefore, software that reduces subjectivity and enhances reproducibility is needed. The aim of the study was to evaluate the reproducibility and objectivity of a novel automated custom-designed PCO detection software. MATERIALS AND METHODS: In total, 165 fixed eyes with intraocular lenses were sectioned to obtain a Miyake Apple view (MAV) image. The capsular bag (CB) with the in situ IOL was removed and imaged using the Olympus DSX110 stereoscope. Central, peripheral, and Soemmering's ring area (SRA) and intensity (SRI) were graded by two ophthalmologists using a scale of 0-4. Software was developed to detect PCO, and these values were correlated with subjective scoring. RESULTS: Intra-observer agreement for MAV and CB images ranged from poor to moderate, with very good agreement for SRI (k = 0.88, 0.86, respectively). Agreement between graders was fair to good (k = 0.31-0.77). Miyake Apple view and capsular bag images showed good correlation; central PCO showed the least correlation for both evaluators (k = 0.29, 0.72). Subjective average grading versus software correlation demonstrated very good correlation for intensity and good for area (r = 0.85, 0.61). Reproducibility of the methodology resulted in good to very good correlation. CONCLUSIONS: Software correlates with previous scoring methods and is a reliable and reproducible system. Moreover, the capsular bag view, as opposed to the Miyake Apple view, allows visualization of the capsular bag directly and avoids overlapping structures (vitreous, cornea) that may interfere with proper PCO quantification.


Asunto(s)
Opacificación Capsular/cirugía , Extracción de Catarata/efectos adversos , Técnicas de Diagnóstico Oftalmológico , Cápsula del Cristalino/patología , Complicaciones Posoperatorias/cirugía , Programas Informáticos , Opacificación Capsular/etiología , Opacificación Capsular/patología , Humanos , Cápsula del Cristalino/cirugía , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/patología , Curva ROC , Reoperación , Reproducibilidad de los Resultados
4.
J Med Imaging (Bellingham) ; 3(2): 027501, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27226977

RESUMEN

Invasive ductal breast carcinomas (IDBCs) are the most frequent and aggressive subtypes of breast cancer, affecting a large number of Canadian women every year. Part of the diagnostic process includes grading the cancerous tissue at the microscopic level according to the Nottingham modification of the Scarff-Bloom-Richardson system. Although reliable, there exists a growing interest in automating the grading process, which will provide consistent care for all patients. This paper presents a solution for automatically detecting regions expressing IDBC in images of microscopic tissue, or whole digital slides. This represents the first stage in a larger solution designed to automatically grade IDBC. The detector first tessellated whole digital slides, and image features were extracted, such as color information, local binary patterns, and histograms of oriented gradients. These were presented to a random forest classifier, which was trained and tested using a database of 66 cases diagnosed with IDBC. When properly tuned, the detector balanced accuracy, F1 score, and Dice's similarity coefficient were 88.7%, 79.5%, and 0.69, respectively. Overall, the results seemed strong enough to integrate our detector into a larger solution equipped with components that analyze the cancerous tissue at higher magnification, automatically producing the histopathological grade.

5.
Ophthalmic Res ; 53(2): 100-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25660418

RESUMEN

PURPOSE: SIRT2 and SIRT6 are members of the sirtuin family and are associated with cancer development and progression in certain tumours, but their expression in retinoblastoma has not been studied. The primary objective of our study was to determine the expression of SIRT2 and SIRT6 in human retinoblastoma cases. METHODS: Eighteen formalin-fixed paraffin-embedded blocks of retinoblastoma cases from the Ocular Pathology Registry at the Henry C. Witelson Ocular Pathology Laboratory were obtained, classified and immunostained for SIRT2 and SIRT6 using mouse monoclonal antibodies. RESULTS: Sixteen cases were poorly differentiated retinoblastoma cases. SIRT2 and SIRT6 were expressed in all cases of retinoblastoma although differences in the staining intensity were found between cases. SIRT2 and SIRT6 expression was also observed in various normal structures of the remaining ocular tissue. CONCLUSIONS: SIRT2 and SIRT6 are expressed in retinoblastoma, as well as in some normal ocular structures. While precise roles of these proteins must still be determined in retinoblastoma, their expression profiles suggest that further functional studies of both SIRT2 and SIRT6 should be pursued in this cancer.


Asunto(s)
Neoplasias de la Retina/metabolismo , Retinoblastoma/metabolismo , Sirtuina 2/metabolismo , Sirtuinas/metabolismo , Niño , Preescolar , Enucleación del Ojo , Femenino , Humanos , Técnicas para Inmunoenzimas , Lactante , Masculino , Neoplasias de la Retina/patología , Neoplasias de la Retina/cirugía , Retinoblastoma/patología , Retinoblastoma/cirugía
6.
Saudi J Ophthalmol ; 26(2): 145-9, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23960985

RESUMEN

Although rare, uveal melanoma is the most common intraocular tumor in adults. Most cases arise from the choroidal layer of the uvea, displaying a discoid, collar-button, or mushroom shaped growth. Histopathologically, neoplasms are classified by the dominant cell type: spindle, epithelioid or mixed spindle cell type. The most important prognostic factors are cell type, nucleolar size, largest tumor dimension, and mitotic figures. Patient prognosis is poor when metastases occur in the liver, one of the main reasons that despite advances in the diagnosis and treatment of uveal melanoma, the mortality rate has not change significantly since 1973.

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