Monitoring the density of corneal endothelial cells (CEC) is essential in the management of corneal diseases. Its manual calculation is time consuming and prone to errors. U-Net, a neural network for biomedical image segmentation, has shown promising results in the automated segmentation of images of healthy corneas and good quality. The purpose of this study was to assess its performance in “real-world” CEC images (variable quality, different ophthalmologic diseases). The outcome measures were: precision and recall of the extraction of CEC, correctness of CEC density estimation, detection of ungradable images. A classical approach based on grayscale morphology and water shedding was pursued for comparison. There was good agreement between the automated image analysis and the manual annotation from the U-Net. R-square from Pearson’s correlation was 0.96. Recall of CEC averaged 0.34 and precision 0.84. The U-Net correctly predicted the CEC density in a large set of images of healthy and diseased corneas, including images of poor quality. It robustly ignored image regions with poor visibility of CEC. The classical approach, however, did not provide acceptable results. R-square from Pearson’s correlation with the ground truth was as low as 0.35.
AimsTo systematically describe the clinical and histopathological features of a case series of conjunctival carcinomatous lesions underlying as—and also masquerading—pyogenic granuloma.MethodsNine cases of conjunctival carcinomatous lesions underlying a pyogenic granuloma (which were clinically predominant) were retrospectively identified. Patients’ records were analysed for demographic data, clinical appearance and the postoperative course. Formalin-fixed paraffin-embedded specimens were routinely processed and stained with H&E and periodic acid-Schiff. Immunohistochemical stains for cytokeratin were performed in selected cases.ResultsAll nine tumours were located in the conjunctiva (bulbar, tarsal, limbal conjunctiva) of patients between 44 and 80 years. The lesions exhibited clinical features of pyogenic granuloma which dominated the clinical appearance. Additional features comprised a papillomatous appearance of the adjacent conjunctiva, a more whitish aspect of the lesion and a history of squamous cell carcinoma (SCC) respectively surgery for other entities. Histopathological analysis revealed a carcinomatous lesion (conjunctival intraepithelial neoplasia or SCC) at the base of a classic pyogenic granuloma in all nine cases. Surgical removal (R0 resection) was performed. Three cases received adjuvant mitomycin C or interferon α2b treatment. Two lesions locally recurred within 2 years after initial presentation.ConclusionCarcinomatous lesions may be accompanied by a pyogenic granuloma which may dominate the clinical pictures. As the tumour is usually located at the base of the lesion, a complete surgical excision followed by histopathological analysis is mandatory for each lesion appearing as conjunctival pyogenic granuloma.
The aim of this study was to investigate HIF-1α, HIF-2α, and ProExC expression in conjunctival intraepithelial neoplasia (CIN), to differentiate between metaplasia and dysplasia, and to access their value as diagnostic and prognostic immunohistochemical markers. Recurrence and progression into SCC (squamous cell carcinoma) were defined as endpoints. Methods Forty-three specimens including CIN I (2), CIN II (9), CIN III (29), with and without metaplasia, and metaplasia alone (3), as well as 21 conjunctival control specimens, were stained with antibodies against HIF-1α, HIF-2α, and ProExC. The percentage of positively stained cells were calculated and used for further analysis. Results The mean percentages of HIF-1α and HIF-2α were not increased in CIN. In comparison, the expressions of these markers were even significantly elevated in control specimens (p < 0.001). Upper epithelial cells in CIN were more often ProExC-positive compared with normal conjunctiva or metaplasia (p = 0.06 and p = 0.07). Cox proportional-hazards analysis was performed for characterization of factors influencing the combined endpoint and showed a significant elevated hazard ratio for staining with ProExC (p = 0.04) compared with HIF-1α (p = 0.26) and HIF-2α (p = 0.49). Conclusion Our study shows that HIF-1α and HIF-2α do not serve as diagnostic or prognostic markers in CIN. ProExC seems to be a potential indicator for CIN, but not a reliable diagnostic marker. However, control specimens occasionally also display a high percentage of ProExC-positive cells and staining over the entire epithelial layer.
Background The demographic change in Germany will lead to an increase in irreversible age-related eye diseases. This will increase the need for specialised care facilities for visually impaired people. Due to reduced mobility, residents in such facilities often do not receive adequate ophthalmological care. New concepts must therefore be considered for this group of patients. One approach is to set up an ophthalmological examination unit within the facility combined with regular visits by an ophthalmologist. We now present the experience with such a model in a home for the blind. Patients and Methods The project was initiated in 2009. Since then there have been visits by medical staff of the Eye Center at Medical Center, University of Freiburg, every two weeks. All patient records (2010 – 2017) were reviewed systematically. The following data were extracted in a structured and anonymous way: Age at first presentation, gender, ophthalmological diagnoses and if a therapy was initiated. This data set was finally analysed descriptively. Results Out of 130 residents aged between 48 and 100 years, half were between 78 and 90 years old. The youngest resident was 48, the oldest 100 years old. The median visual acuity was 0.2. Sixty percent of the residents had at least mild visual impairment according to the WHO (visual acuity < 0.5; category 1 – 6). In one of 6 – 7 residents, visual acuity could not be determined using Snellen charts. The most frequent ophthalmological diagnoses included cataract (44%), age-related macular degeneration (36%) and glaucoma (29%). In 67 residents (52%), the ophthalmological examination lead to treatment, such as application of local therapy or planning an operation. Conclusion In every second resident, the ophthalmologistʼs visit lead to treatment during the observation period. This underlines the difficulty of providing ophthalmological care even in specialised institutions for the blind and visually impaired, which is possibly due to the residentsʼ mobility problems. The concept presented here has established a low-threshold, sustainable and high-quality ophthalmological service on site. These positive experiences indicate that corresponding measures may also be useful for other locations. However, in order to implement such a project on a larger scale, suitable financing and accounting modalities for the construction measures, the nursing staff and the ophthalmological procedure still need to be developed.
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