Automatic segmentation of layers in chorio-retinal complex using Graph-based method for ultra-speed 1.7 MHz wide field swept source FDML optical coherence tomography.

The posterior segment of the human eye complex contains two discrete microstructure and vasculature network systems, namely, the retina and choroid. We present a single segmentation framework technique for segmenting the entire layers present in the chorio-retinal complex of the human eye using optical coherence tomography (OCT) images. This automatic program is based on the graph theory method. This single program is capable of segmenting seven layers of the retina and choroid scleral interface. The graph theory was utilized to find the probability matrix and subsequent boundaries of different layers. The program was also implemented to segment angiographic maps of different chorio-retinal layers using "segmentation matrices." The method was tested and successfully validated on OCT images from six normal human eyes as well as eyes with non-exudative age-related macular degeneration (AMD). The thickness of microstructure and microvasculature for different layers located in the chorio-retinal segment of the eye was also generated and compared. A decent efficiency in terms of processing time, sensitivity, and accuracy was observed compared to the manual segmentation and other existing methods. The proposed method automatically segments whole OCT images of chorio-retinal complex with augmented probability maps generation in OCT volume dataset. We have also evaluated the segmentation results using quantitative metrics such as Dice coefficient and Hausdorff distance This method realizes a mean descent Dice similarity coefficient (DSC) value of 0.82 (range, 0.816-0.864) for RPE and CSI layer.

Adverse events following COVID-19 immunisation (AEFI) at a COVID-19 vaccination centre: An observational analytical study.

Objectives: The aim of this study was to determine the adverse events following immunisation (AEFI) in various age groups after coronavirus disease 2019 (COVID-19) vaccination and assess the association of comorbidities with AEFI. Methods: An observational analytical study was conducted among the general population who had received both doses of the COVID-19 vaccine. A total of 389 participants from the 18-44 years age group, 380 participants from the 45-60 years age group and 373 participants from the 60 plus age group were enrolled in the study after verbal and written consent. Simple random sampling was used to select the study participant in each group. Home visits were made to fill out the semi-structured questionnaire for information regarding any adverse event following COVID-19 immunisation. Results: Overall, 31.9%, 19.74% and 15.17% of >60, 45-60 and 18-44 years, respectively, reported any AEFI after COVID-19 immunisation. The severity of AEFI was more among the 18-44 years age group (66.1%) followed by 45-60 years (30.67%) and less among the older one, that is, >60 years. Fever and pain with inflammation at the injection site were the most common AEFI reported after any dose. There was no association of comorbidity with the severity of AEFI. Conclusion: Since the AEFI reported are very less, most of them were of a minor type and were general immunogenic reactions of any vaccine. Hence the COVID-19 vaccines are very safe, and uptake should be high among all the recommended age groups to combat the severity of the COVID-19 disease.