scholarly journals Automatic Identification and Intuitive Map Representation of the Epiretinal Membrane Presence in 3D OCT Volumes

Sensors ◽  
2019 ◽  
Vol 19 (23) ◽  
pp. 5269 ◽  
Author(s):  
Sergio Baamonde ◽  
Joaquim de Moura ◽  
Jorge Novo ◽  
Pablo Charlón ◽  
Marcos Ortega

Optical Coherence Tomography (OCT) is a medical image modality providing high-resolution cross-sectional visualizations of the retinal tissues without any invasive procedure, commonly used in the analysis of retinal diseases such as diabetic retinopathy or retinal detachment. Early identification of the epiretinal membrane (ERM) facilitates ERM surgical removal operations. Moreover, presence of the ERM is linked to other retinal pathologies, such as macular edemas, being among the main causes of vision loss. In this work, we propose an automatic method for the characterization and visualization of the ERM’s presence using 3D OCT volumes. A set of 452 features is refined using the Spatial Uniform ReliefF (SURF) selection strategy to identify the most relevant ones. Afterwards, a set of representative classifiers is trained, selecting the most proficient model, generating a 2D reconstruction of the ERM’s presence. Finally, a post-processing stage using a set of morphological operators is performed to improve the quality of the generated maps. To verify the proposed methodology, we used 20 3D OCT volumes, both with and without the ERM’s presence, totalling 2428 OCT images manually labeled by a specialist. The most optimal classifier in the training stage achieved a mean accuracy of 91 . 9 % . Regarding the post-processing stage, mean specificity values of 91 . 9 % and 99 . 0 % were obtained from volumes with and without the ERM’s presence, respectively.

Sensors ◽  
2021 ◽  
Vol 21 (17) ◽  
pp. 5752
Author(s):  
Milan Ondrašovič ◽  
Peter Tarábek

Homography mapping is often exploited to remove perspective distortion in images and can be estimated using point correspondences of a known object (marker). We focus on scenarios with multiple markers placed on the same plane if their relative positions in the world are unknown, causing an indeterminate point correspondence. Existing approaches may only estimate an isolated homography for each marker and cannot determine which homography achieves the best reprojection over the entire image. We thus propose a method to rank isolated homographies obtained from multiple distinct markers to select the best homography. This method extends existing approaches in the post-processing stage, provided that the point correspondences are available and that the markers differ only by similarity transformation after rectification. We demonstrate the robustness of our method using a synthetic dataset and show an approximately 60% relative improvement over the random selection strategy based on the homography estimation from the OpenCV library.


Author(s):  
Abdulrahman M. Ibrahem ◽  
Salah Q. Mahmood ◽  
Muhammed Babakir-Mina ◽  
Salar Ibrahim Ali ◽  
Bakhtyar Kamal Talabany

Knowledge and practice of public, especially patients about eye diseases are important to reduce magnitude of human blindness. Vision and sight are very essential because they allow us to connect to each other’s. In accordance to the recently published data; the estimation of 253 million people lives with vision impairment, 36 million are blind and 217 million suffer from moderate to severe vision impairment. A descriptive cross-sectional study was conducted at Shahid Dr. Aso Hospital in Sulaimani city-Iraq, from April to August 2017 by face-to-face interview through close ended questionnaire for data collecting. All data were analyzed by Statistical Package for Social Sciences version 22.0 software. P-value of < 0.05 was considered as a statistically significant. A total of 430 patients were randomly chosen to participate in the study. They were 254 (59.1%) males and 176 (40.9%) females. 76.7% of respondents was worrying about vision loss, 0.7% was worrying about hair loss. Of the participants, 32.8% was with a good knowledge level and 40.5% was with a poor knowledge level, as well as 3.1% was in a good practice and 58.8% was in a poor practice level. Female knowledge mean score was 9.53±4.96 and male knowledge mean score was 8.42±5.45, the practice mean score of males was 4.33±1.96 and mean practice score of females was 4.13±1.93. The study data indicate the worrying of participates about vision loss is in the highest proportion and the awareness and practice of patients about eye diseases is unsatisfactory. Health education campaigns are needed to improve personal awareness about vision related problems and for better eye health.


Author(s):  
Tran Dai Tri Han ◽  
Keiko Nakamura ◽  
Kaoruko Seino ◽  
Vo Nu Hong Duc ◽  
Thang Van Vo

This study examined the prevalence of cognitive impairment among older adults in central Vietnam and the roles of communication (with or without communication devices) in the association between cognitive impairment and hearing loss. This cross-sectional study was performed on 725 randomly selected community-dwelling older adults aged ≥60 years from Thua Thien Hue province, Vietnam. Participants attended a face-to-face survey. Sociodemographic characteristics, social interaction with or without communication devices, health status and cognitive function using the Mini-Mental State Examination were reported. Ordinal logistic regression analysis was performed to quantify the association between hearing loss and cognitive function by frequency of communication with and without devices. Mild and severe cognitive impairment had prevalence rates of 23.6% and 19.3%, respectively. Cognitive impairment was more prevalent among older adults with hearing-loss, vision loss and difficulties with instrumental activities of daily living (IADL). The association between hearing loss and cognitive impairment was not significant when older adults had frequent communication with others using devices. This study presented the relatively high prevalence of cognitive impairment in community-dwelling older adults in Vietnam. Frequent communication using devices attenuated the association between hearing loss and cognitive impairment.


Biomolecules ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1150
Author(s):  
Dixa Gautam ◽  
Michelle G. Pedler ◽  
Devatha P. Nair ◽  
Jonathan Mark Petrash

Cataracts are a leading cause of blindness worldwide. Surgical removal of cataracts is a safe and effective procedure to restore vision. However, a large number of patients later develop vision loss due to regrowth of lens cells and subsequent degradation of the visual axis leading to visual disability. This postsurgical complication, known as posterior capsular opacification (PCO), occurs in up to 30% of cataract patients and has no clinically proven pharmacological means of prevention. Despite the availability of many compounds capable of preventing early steps in PCO development, there is currently no effective means to deliver such therapies into the eye for a suitable duration. To model a solution to this unmet medical need, we fabricated acrylic substrates as intraocular lens (IOL) mimics scaled to place into the capsular bag of the mouse lens following a mock-cataract surgery. Substrates were coated with a hydrophilic crosslinked acrylate nanogel designed to elute Sorbinil, an aldose reductase inhibitor previously shown to suppress PCO. Insertion of the Sorbinil-eluting device into the lens capsule at the time of cataract surgery resulted in substantial prevention of cellular changes associated with PCO development. This model demonstrates that a cataract inhibitor can be delivered into the postsurgical lens capsule at therapeutic levels.


2021 ◽  
pp. bjophthalmol-2020-317461
Author(s):  
Sean Mullany ◽  
Lewis Xiao ◽  
Ayub Qassim ◽  
Henry Marshall ◽  
Puya Gharahkhani ◽  
...  

Background/aimsRecent research suggests an association between normal-tension glaucoma (NTG) and dementia. This study investigated whether cognitive impairment is more strongly associated with NTG than high tension glaucoma (HTG) using cognitive screening within an Australiasian Glaucoma Disease Registry.MethodsThe authors completed a case–control cross-sectional cognitive screening involving 290 age-matched and sex-matched NTG participants and HTG controls aged ≥65 randomly sampled from the Australian and New Zealand Registry of Advanced Glaucoma. Cognitive screening was performed using the Telephone Version of the Montreal Cognitive Assessment (T-MoCA). The T-MoCA omits points requiring visual interpretation, accounting for confounding factors related to vision loss in visually impaired participants. Cognitive impairment was defined by a T-MoCA score of <11/22. Cognition was compared between NTG and HTG participants using predetermined thresholds and absolute screening scores.ResultsA total of 290 participants completed cognitive assessment. There were no differences in NTG (n=144) and HTG (n=146) cohort demographics or ocular parameters at baseline. Cognitive impairment was more prevalent in the NTG cohort than the HTG cohort (OR=2.2; 95% CI 1.1 to 6.7, p=0.030). Though a linear trend was also observed between lower absolute T-MoCA scores in the NTG cohort when compared with the HTG cohort, this association was not statistically significant (p=0.108).ConclusionThis study demonstrated an association between NTG status and poor cognition, supporting the hypothesis that there exists a disease association and shared pathoaetiological features between NTG and dementia.


2018 ◽  
Vol 103 (9) ◽  
pp. 1314-1319 ◽  
Author(s):  
Eva K Fenwick ◽  
Ryan E K Man ◽  
Alfred Tau Liang Gan ◽  
Neelam Kumari ◽  
Charlene Wong ◽  
...  

Background/aimsTo assess the independent impact of diabetic retinopathy (DR) on three domains of vision-related quality of life (VRQoL) in a Chinese Singapore population.MethodsThe Singapore Chinese Eye Study (n=3353; 2009–2011) was a population-based, prospective, cross-sectional study conducted at the Singapore Eye Research Institute. The study population included 292 adults with diabetes, with and without DR. DR (better eye) was categorised as presence and absence of any DR; severity of DR (no vision-threatening DR (VTDR); severe non-proliferative DR (NPDR); PDR and/or clinically significant macular oedema and VTDR). Our main outcome was VRQoL which was measured using Rasch-calibrated scores from the ‘Reading’, ‘Mobility’ and ‘Emotional’ domains of the Impact of Vision Impairment questionnaire. The relationship between DR and VRQoL was assessed using multiple linear regression models.ResultsOf the 292 individuals (mean age 61.35 ± 9.66 years; 55.8% male), 201 (68.8%), 49 (16.8%), 20 (6.8%), 22 (7.5%) and 27 (9.2%) had no DR, minimal-mild NPDR, moderate-severe NPDR, PDR and VTDR, respectively. Any DR and VTDR were independently associated with 6% and 12% worse Reading scores and 7% and 18% poorer Emotional well-being, respectively, compared with those without DR. These associations persisted after separate adjustment for visual impairment and presenting visual acuity. No significant difference was found in the Mobility domain between persons with and without DR.ConclusionsWe documented that DR, particularly VTDR, was independently associated with restrictions in Reading and Emotional well-being. Understanding factors underlying the detrimental DR-VRQoL relationship may optimise rehabilitation outcomes for individuals with DR.


Electronics ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 134
Author(s):  
Federica Uberti ◽  
Lucia Frosini ◽  
Loránd Szabó

A new procedure for the design and optimization of the rotor laminations of a synchronous reluctance machine is presented in this paper. The configuration of the laminations is symmetrical and contains fluid-shaped barriers. The parametrization principle is used, which executes variations in the lamination geometry by changing the position, thickness and shape of the flux barriers. Hence, the optimization procedure analyzes the various configurations through finite element simulations, by means of the communication between MATLAB and Flux 2D. In the post processing stage, the best geometry which optimizes mean torque, torque ripple, efficiency and power factor is selected. Once the best rotor configuration is defined, further investigations allow improving its performance by modifying the current angle, the stator winding and the thickness of the radial ribs.


2021 ◽  
Vol 7 (2) ◽  
pp. 366-371
Author(s):  
Sunil Ganekal ◽  
Varun Ganekal

To compare the visual acuity outcomes after surgical treatment of epiretinal membranes (ERM) in cases with and without ectopic inner foveal layers (EIFL). : A total of 100 eyes of 98 patients with idiopathic ERM were retrospectively staged according to the newer OCT classification and divided into two groups on the basis of presence or absence of EIFL. The two groups were evaluated for various parameters including visual acuity, thickness of the EIFL, re-appearance of the foveal contour, outer retinal changes and complications before and after ERM peeling. Correlation analysis was done using chi square test and p-values were obtained for corresponding variables.: Of 100 eyes with ERM, 20% had stage 1, 29% had stage 2, 42% had stage3 & 9% had stage 4 disease. VA was worse in eyes with EIFL as compared those without it. Correlation of VA with EIFL thickness however was not significant. Surgical removal of ERM didn’t alter EIFL frequency though the thickness decreased. New EIFL appeared in 4% eyes and 35% demonstrated thickened fovea after surgery. Anatomical reappearance of foveal contour was poorer in eyes with EIFL. Outer retinal changes were more common in non EIFL eyes. Lamellar holes and nontractional cysts were more common in EIFL eyes.: EIFL is a significant prognostic tool to predict the visual outcome of surgery in cases of Epiretinal membrane. EIFL eyes did not regain foveal contour, had less outer retinal damage but were associated with poorer visual outcomes.


2020 ◽  
Author(s):  
Wendy Andrusjak ◽  
Ana Barbosa ◽  
Gail Mountain

Abstract Background: Hearing and vision loss in older people has proven to affect physical and mental health and increase the speed of cognitive decline. Studies have proven certain practices and aspects of staff knowledge increase the effective care of residents’ ears and eyes, yet it is not known which of these are being implemented in care homes. This study aims to identify the gaps in staff knowledge and underused practices evident in long term care homes when identifying and managing hearing and vision difficulties in older residents. Methods: This study used a cross-sectional survey design. Survey questions were informed by the existing literature and were focused on practices, staff knowledge, and other aspects that have shown to affect residents’ hearing and vision care. The survey was sent to care homes across England between November 2018 and February 2019 both via Email and in paper format for care home staff to complete. Descriptive statistics and Chi-Square analysis was used to assess the factors particularly influencing the current care being provided to care home residents. Results: A total of 400 care home staff responded from 74 care homes. The results revealed that screening tools are rarely used by staff to identify hearing and vision impairments, care homes have limited access to other assistive devices, and audiology services do not regularly assess care home residents. A majority of staff were also not entirely confident in their knowledge of ear and eye care. Responses were also affected by the respondents’ job role, length of time working in care homes and also the care home type and care home capacity revealing a lack of standardised practice and shared communication. Conclusion: This study identifies which practices known to facilitate ear and eye care are currently under used in care homes across England and what particularly staff are not knowledgeable on when it comes to ear and eye care. This can now inform future research of the areas requiring improvement to as effectively address to acknowledged slow identification and poor management of hearing and vision loss in older people residing in care homes.


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