Iris Position Research Articles

CUSTOMISED OCULAR PROSTHESIS FABRICATION - A CASE SERIES

Loss of an eye, whether due to trauma or medical necessity, can lead to significant physical and psychological distress This article delves into the profound impact of ocular prosthetics in alleviating the physical and psychological repercussions of eye loss. Acrylic resin has been identified as an optimal material for its durability, aesthetic fidelity, and biocompatibility in fabricating ocular prostheses. Beyond restoring facial symmetry and enhancing aesthetics, these prostheses significantly bolster patient self-confidence and overall quality of life. The series comprehensively examines four distinct methods for iris positioning and prosthesis characterization, crucial for imparting natural vitality to the prosthetic eye. Each case underscores the importance of personalized care in ocular prosthetics, emphasizing the advantages over standard stock prostheses.

Survey on Eye Gaze Tracking to Control Cursor Movement

In Controlling the mouse by a physically challenged person is really a tough one. To find a solution for the people who cannot use the Mouse physically, we have proposed this mouse cursor control using Eye Movements. Eye gaze is an alternative way of accessing a computer using eye movements to control the mouse. For someone who fine touch screens, mouse inaccessible, eye gaze is an alternative method to allow a user to operate their computer, using the movement of their eyes. Eye movement can be regarded as a pivotal real-time input medium for human-computer communication, which is especially important for people with physical disability. In order to improve the reliability, mobility, and usability of eye tracking technique in user-computer dialogue, a novel eye control system is proposed in this system using Webcam and without using any extra hardware. The proposed system focuses on providing a simple and convenient interactive mode by only using user’s eye. The usage flow of the proposed system is designed to perfectly follow human natural habits. The proposed system describes the implementation of both iris and movement of cursor according to iris position which can be used to control the cursor on the screen using webcam and implemented using Python

Intelligent learners distraction and drowsiness prediction through EEG signal and iris angel position with brain vision algorithm

Distraction and fatigue are serious issues in online learning, and they directly impact educational outcomes. To achieve excellent academic achievement, students need to focus on their studies without being distracted or fatigued. Learners frequently overlook crucial information, directions, and concepts while they are passive and sleepy. They tend to miss important content, instructions, and concepts. Iris Angle Position (IAP) and electroencephalography (EEG) were used in this model to identify the behaviour of learners. Specifically, a Deep Convolutional Neural Network (DCNN) is constructed to extract IAP in order to accurately capture the learner’s facial area. EEG signals are effectively handled and sorted using deep reinforcement learning (DRL). The learners’ facial landmarks are retrieved from a frame using the dlib toolbox. Only eye landmark points from face landmarks alone are focused on in order to determine the learner’s behaviour. When the learners EEG signals and Iris positions are monitored simultaneously, it’s helpful to identify the learner’s fatigue state (LFS) and the learner’s distraction state (LDS). The Brain Vision Algorithm (BVA) uses iris position and minimal facial landmarks, along with brain activity, to properly identify the learner’s level of distraction and exhaustion. When a student is detected as being preoccupied or sleepy, an alert goes off automatically, and the educator gets performance feedback. Iris position data and brain-computer interface-based EEG signal values are utilised to identify distraction and sleepiness. Comparative tests have demonstrated that this innovative method offers fast and high-accuracy student activity detection in virtual learning settings. Applying the suggested approach to different existing classifiers yields an F-Score of 91.92%, a recall of 93.87%, and a precision of 92.37% . The results showed that the detection rates for both distracted and sleepy phases were higher than those attained with other currently used techniques.

Computational methodology to support functional vision assessment in premature infants: A viability study.

Premature newborns have a higher risk of abnormal visual development and visual impairment. To develop a computational methodology to help assess functional vision in premature infants by tracking iris distances. This experimental study was carried out with children up to two years old. A pattern of image capture with the visual stimulus was proposed to evaluate visual functions of vertical and horizontal visual tracking, visual field, vestibulo-ocular reflex, and fixation. The participants' visual responses were filmed to compose a dataset and develop a detection algorithm using the OpenCV library allied with FaceMesh for the detection and selection of the face, detection of specific facial points and tracking of the iris positions is done. A feasibility study was also conducted from the videos processed by the software. Forty-one children of different ages and diagnoses participated in the experimental study, forming a robust dataset. The software resulted in the tracking of iris positions during visual function evaluation stimuli. Furthermore, in the feasibility study, 8 children participated, divided into Pre-term and Term groups. There was no statistical difference in any visual variable analyzed in the comparison between groups. The computational methodology developed was able to track the distances traveled by the iris, and thus can be used to help assess visual function in children.

Computer Vision Mouse for Tetraplegic Individuals to Access Computers Using Facial Expressions

Abstract: Controlling the mouse by a physically challenged person is really a tough one. To find a solution for the people who cannot use the Mouse physically, we have proposed this mouse cursor control using Eye Movements. Eye gaze is an alternative way of accessing a computer using eye movements to control the mouse. For someone who fine touchscreens, mouse inaccessible, eye gaze is an alternative method to allow a user to operate their computer, using the movement of their eyes. Eye movement can be regarded as a pivotal real-time input medium for human-computer communication, which is especially important for people with physical disability. In order to improve the reliability, mobility, and usability of eye tracking technique in user-computer dialogue, a novel eye control system is proposed in this system using Webcam and without using any extra hardware. The proposed system focuses on providing a simple and convenient interactive mode by only using user’s eye. The usage flow of the proposed system is designed to perfectly follow human natural habits. The proposed system describes the implementation of both iris and movement of cursor according to iris position which can be used to control the cursor on the screen using webcam and implemented using Python.

A novel technique for CAD-CAM assisted digital ocular prosthesis.

There are various techniques available for constructing a custom ocular prosthesis. The present technique report describes a digital workflow for constructing an ocular prosthesis using computed tomography integrated with digital technologies. The outer region of the healthy eyeball was segmented to produce the top surface of the prosthesis, while the contour and bottom surface were segmented from the tissue bed of the anophthalmic socket. The iris position was determined by tracing the optical nerve and confirmed by superimposing the patient's facial scan onto the soft tissue model of the computed tomography. Using these parameters, a standard tessellation language file for the ocular prosthesis was generated and 3D printed. The iris was then printed via UV technology using digital photographs of the patient's contralateral eye; characterization of the sclera and the final layer of clear acrylic resin were done conventionally.

Augmented reality filters for iris positioning in orbital prosthesis: A clinical report

Mid-facial defects involving the eye can result in severe emotional and psychological trauma for the affected individual, apart from the loss of vision. Prosthetic rehabilitation with an orbital prosthesis can camouflage such defects when surgical treatments are limited. The fabrication of an orbital prosthesis requires precise positioning of the iris for an optimal esthetic outcome. Different techniques for accurate iris positioning in orbital or ocular prostheses have been described, but they have been subjective or require elaborate equipment. This clinical report describes a novel and digital solution for iris positioning with the help of augmented reality filters using a smartphone and Instagram app.

Custom Ocular Prosthesis with an Innovative Approach of Iris Positioning Using Bite Fork: A Case Report

Custom Ocular Prosthesis with an Innovative Approach of Iris Positioning Using Bite Fork: A Case Report

An intelligent strabismus detection method based on convolution neural network

Strabismus is one of the widespread vision disorders in which the eyes are misaligned and asymmetric. Convolutional neural networks (CNNs) are properly designed for analyzing images and detecting texture patterns. In this paper, we proposed a system that uses deep learning CNN applications for automatically detecting and classifying strabismus disorder. The proposed system includes two main stages: first, the detection of facial eye segmentation using the viola-jones algorithm. The second stage is to map the segmented eye area according to the iris position of each eye. This method is applied to three strabismus datasets, gathered as digital images. The second section covers the segmentation of the eye region. Besides, the evaluation equations for measuring system performance. The system has undergone numerous experiments in various stages to simulate and analyze the detection performance of CNN layers through different classifiers and variant thresholds ratio. The researchers investigated the experimental outcomes during the training and testing phases and obtained promising results that exhibit the effectiveness of the proposed system. According to the results, the accuracy of this technique reached 95.62%.

An improved strabismus screening method with combination of meta-learning and image processing under data scarcity.

PurposeConsidering the scarcity of normal and strabismic images, this study proposed a method that combines a meta-learning approach with image processing methods to improve the classification accuracy when meta-learning alone is used for screening strabismus.MethodsThe meta-learning approach was first pre-trained on a public dataset to obtain a well-generalized embedding network to extract distinctive features of images. On the other hand, the image processing methods were used to extract the position features of eye regions (e.g., iris position, corneal light reflex) as supplementary features to the distinctive features. Afterward, principal component analysis was applied to reduce the dimensionality of distinctive features for integration with low-dimensional supplementary features. The integrated features were then used to train a support vector machine classifier for performing strabismus screening. Sixty images (30 normal and 30 strabismus) were used to verify the effectiveness of the proposed method, and its classification performance was assessed by computing the accuracy, specificity, and sensitivity through 5,000 experiments.ResultsThe proposed method achieved a classification accuracy of 0.805 with a sensitivity (correct classification of strabismus) of 0.768 and a specificity (correct classification of normal) of 0.842, whereas the classification accuracy of using meta-learning alone was 0.709 with a sensitivity of 0.740 and a specificity of 0.678.ConclusionThe proposed strabismus screening method achieved promising classification accuracy and gained significant accuracy improvement over using meta-learning alone under data scarcity.

Custom - made ocular prosthesis: A novel way of iris positioning

Loss of any part from the maxillofacial region can have traumatic impact on the psychology of an individual. A prime role in facial expression is played by the eyes and tissues around it. A missing eye can be rehabilitated prosthetically. The main aim is to achieve adequate esthetic and function with rehabilitation to improve lifestyle and social acceptance. The ocular prosthesis can be a stock eye shell or custom-made eye. Exact matching of the contralateral eye is of utmost importance. Here a novel way of iris positing has been done. Thus, this case report presents a unique technique for the fabrication of a custom-made unilateral ocular prosthesis.

Miniaturized Quarter-Mode SIW Filters Loaded by Dual-Mode Microstrip Resonator With High Selectivity and Flexible Response

A novel miniaturized multilayer quarter-mode substrate integrated waveguide (QMSIW) filter with high selectivity and wide stopband is proposed. First, an innovative multilayer dual-mode microstrip resonator is proposed to couple the QMSIW resonators located at the upper and lower substrate layers. The combination of the dual-mode resonator with the two QMSIW cavities leads to a fourth-order filtering response. Then, the coupling iris is opened at the position, where the magnetic field distribution in the QMSIW cavity achieves a peak value. Finally, sharp skirt is obtained by composing the modified box-like topology. In addition, different responses could be achieved by changing the position of the coupling iris, resulting in a wide stopband and flexible response. The size of the filter is also reduced through the multilayer QMSIW configuration and miniaturized multilayer dual-mode microstrip resonator.

Modified impression tray and iris positioning ocular prosthesis of post enucleation socket syndrome: case report

The cosmetic disfigurements which arise due to loss of orbital volume after enucleation of an eye include enophthalmus, superior sulcus deformity, upper eyelid ptosis, and lower eyelid laxity. The treatment can be either conservative or surgical. For patients who does not want to undergo further surgical procedures, the conservative treatment is simple, non-invasive, and appropriate. This case report describes modified impression tray and iris positioning technique of post enucleation socket syndrome to achieve aesthetics and function. A 65-year-old male patient reported to the Dental Hospital Universitas Sumatera Utara with the chief complaint of facial disfigurement due to loss of the right eye. Patient had enucleation 6 months ago and using conformer after surgery. The diagnosis was post enucleation socket syndrome. Clear acrylic sclera as a tray without handgrip will precisely records of the palpebre con- vexity and specified socket. The use of eyebrow ruler helps accurately determine the symmetrical iris position com- pared to only visually determining which is subjective with the possibility of interobserver errors. It was concluded that clear acrylic sclera as a tray and eyebrow ruler to determine the position of iris resulting in patient satisfaction due to aesthetics and function.

Iris positioning technique by using face symmetric measurement tool on the custom ocular prosthesis: a case report

Loss of eye can have a major psychological impact on the patient. To overcome this problem, an ocular prosthetic must have been fabricated similar with the natural eye. Various techniques are documented to determine the symme- trical bilateral iris position; these methods can be subjective and have no measurement guidelines. A 20-year-old male patient came to the Prosthodontic Clinic of Dental Hospital Universitas Sumatera Utara with the diagnosis is post enucleation socket syndrome. Determination of the iris position using the face symmetric measurement-tool by focus to the vertical and horizontal lines of the facial symmetry guide. Confirm the alignment of the vertical lines by connecting the trichion–glabella–subnasal–gnathion guide points so that they vertically divide the two sides of the face, then the two horizontal lines by connecting the left-right cheilon with the mesial-distal canthus of the right and left eyes. This tool is like a face mask with vertical and horizontal guidelines connecting the symmetrical guide points of the face accompanied by centimeters and millimetres making it easy to measure distances and sizes of the iris symmetrically. The use of this tool has given good results in determining the position of the iris because its simplicity and can see facial symmetry.

A Scalable Off-the-Shelf Framework for Measuring Patterns of Attention in Young Children and its Application in Autism Spectrum Disorder.

Autism spectrum disorder (ASD) is associated with deficits in the processing of social information and difficulties in social interaction, and individuals with ASD exhibit atypical attention and gaze. Traditionally, gaze studies have relied upon precise and constrained means of monitoring attention using expensive equipment in laboratories. In this work we develop a low-cost off-the-shelf alternative for measuring attention that can be used in natural settings. The head and iris positions of 104 16-31 months children, an age range appropriate for ASD screening and diagnosis, 22 of them diagnosed with ASD, were recorded using the front facing camera in an iPad while they watched on the device screen a movie displaying dynamic stimuli, social stimuli on the left and nonsocial stimuli on the right. The head and iris position were then automatically analyzed via computer vision algorithms to detect the direction of attention. Children in the ASD group paid less attention to the movie, showed less attention to the social as compared to the nonsocial stimuli, and often fixated their attention to one side of the screen. The proposed method provides a low-cost means of monitoring attention to properly designed stimuli, demonstrating that the integration of stimuli design and automatic response analysis results in the opportunity to use off-the-shelf cameras to assess behavioral biomarkers.

A sparkle in the eye: Illumination cues and lightness constancy in the perception of eye contact

In social interactions, our sense of when we have eye contact with another person relies on the distribution of luminance across their eye region, reflecting the position of the darker iris within the lighter sclera of the human eye. This distribution of luminance can be distorted by the lighting conditions, consistent with the fundamental challenge that the visual system faces in distinguishing the nature of a surface from the pattern of light falling upon it. Here we perform a set of psychophysics experiments in human observers to investigate how illumination impacts on the perception of eye contact. First, we find that simple changes in the direction of illumination can produce systematic biases in our sense of when we have eye contact with another person. Second, we find that the visual system uses information about the lighting conditions to partially discount or ‘explain away’ the effects of illumination in this context, leading to a significantly more robust sense of when we have eye contact with another person. Third, we find that perceived eye contact is affected by specular reflections from the eye surface in addition to shading patterns, implicating eye glint as a potential cue to gaze direction. Overall, this illustrates how our interpretation of social signals relies on visual mechanisms that both compensate for the effects of illumination on retinal input and potentially exploit novel cues that illumination can produce.

Fast Iris localization using Haar-like features and AdaBoost algorithm

Traditional iris recognition methods, which are still preferred against artificial intelligence (AI) approaches in practical applications, are often required to capture high-grade iris samples by an iris scanner for accurate subsequent processing. To reduce the system cost for mass deployment of iris recognition, pricey scan devices can be replaced by the average quality cameras combined with additional processing algorithm. In this paper, we propose a Haar-like-feature-based iris localization method to quickly detect the location of human iris in the images captured by low-cost cameras for the ease of post-processing stages. The AdaBoost algorithm was chosen as a learning method for training a cascade classifier using Haar-like features, which was then utilized to detect the iris position. The experimental results have shown acceptable accuracy and processing speed for this novel cascade classifier. This achievement stimulates us to implement this novel capturing device in our iris recognition.

Comparison of Two Novel Techniques for Iris Centering in Ocular Prosthesis

AbstractEyes are among the first features of the face to be noticed. Loss of an eye due to congenital, traumatic, or pathologic etiologies causes disfigurement and loss of sensory feedback. It leaves a psychological impact on the patient; thus, prosthesis should be provided at the earliest to raise the spirits of the afflicted. Iris positioning is one of the important steps in fabricating customized ocular prosthesis. In facial asymmetry cases, comparison of both irises together can be a major disadvantage. This case report illustrates the use of a regular eyeglass in one technique and the use of a bioart facebow in the second technique for centering of iris in a customized ocular prosthesis to overcome the disadvantages of earlier used standard techniques (McArthur’s ocular locator and fixed calliper, pupillometer, visual judgement, and graph grid) of iris centering.

Modification of techniques in the fabrication of ocular prostheses: A case report

To report a modification technique in ocular prostheses impression. The treatment procedure with two stages of impressions, preliminary impression to get a preliminary model for special tray fabrication, then the physiological impression are performed by instructing the patient to move the eyes physiologically in all directions using the vinyl polysiloxane impression material. Inter-pupil measurement with a special ruler by making a guideline on the patient's face during the try-in process. Custom ocular prostheses are made specifically according to the anatomy of the patient. It provides the benefits of eyeball movement enhancement, the proper suitability of the iris position as well as adjacent natural eyes, and good adaptation to surrounding tissues. Custom ocular prostheses were made specifically according to the anatomy of the patient, so it provides the benefits of eyeball movement enhancement, the proper suitability of the iris position.

Modelling floppy iris syndrome and the impact of pupil size and ring devices on iris displacement

IntroductionThe aim of this paper was to further develop a previously described finite element model which equates clinical iris billowing movements with mechanical buckling behaviour, simulating floppy iris syndrome. We wished to evaluate the impact of pupil dilation and mechanical devices on normal iris and floppy iris models.MethodsTheoretical mathematical modelling and computer simulations were used to assess billowing/buckling patterns of the iris under loading pressures for the undilated and dilated normal iris, the undilated and dilated floppy iris, and additionally with a mechanical ring device.ResultsFor the normal iris, billowing/buckling occurred at a critical pressure of 19.92 mmHg for 5 mm pupil size, which increased to 28.00 mmHg (40.56%) with a 7 mm pupil. The Malyugin ring device significantly increased critical initiating buckling pressures in the normal iris scenario, to 34.58 mmHg (73.59%) for 7 mm ring with boundary conditions I (BC I) and 34.51 mmHg (73.24%) with BC II. For the most floppy iris modelling (40% degradation), initiating buckling value was 18.04 mmHg (−9.44%), which increased to 28.39 mmHg (42.52%) with the 7 mm ring. These results were much greater than for normal undilated iris without restrictive mechanical expansion (19.92 mmHg).ConclusionThis simulation demonstrates that pupil expansion devices inhibit iris billowing even in the setting of floppy iris syndrome. Our work also provides a model to further investigate the impact of pupil size or pharmacological interventions on anterior segment conditions affected by iris position.