Ahmed Sayed, Ph.D

Repeatability Assessment of Monocular and Binocular Visual Field Measurements with a Head Mounted Display

The Association for Research in Vision and Ophthalmology  

May 2022

The Effect of Visual Field

Investigative Ophthalmology & Visual Science  New Orleans, LA 2023

Repeatability Assessment of Monocular and Binocular Visual Field Measurements with a Head Mounted Display

The Association for Research in Vision and Ophthalmology  May 2022

Digital Glasses for Visual Rehabilitation of Glaucoma Patients suffering from Visual Fields Defects

The Association for Research in Vision and Ophthalmology  Vancouver, Canada

Digital Glasses for Visual Rehabilitation of Glaucoma Patients with Visual Fields Defects: Pilot Study

American Academy of Ophthalmology  Chicago

Modeling Procedures for Breast Cancer Diagnosis Based On Clinical Elastography Images

IEEE 12th International Conference on Computer Engineering and Systems  Cairo

A New Method for Biomechanical Data Acquisition in Remote Laboratory Delivery During the COVID-19 Pandemic

ASEE North Midwest Section Annual Conference  Ames, IA 2020

The effect of see-through digital spectacles on eye scanning behavior of patients with peripheral visual field losses

The Association for Research in Vision and Ophthalmology, ARVO  Baltimore, Maryland 2020

Biomechanics

This course presents the fundamentals of human biomechanics and introduces multiple applications to sports, rehabilitation, and occupational biomechanics. The course starts with the study of engineering dynamics parameters and the forces and moments causing motion. Studies of linear motion, rotational motion, dynamic force analysis, work and energy, and impulse and momentum problems are illustrated. The course then discusses the application of kinematic and kinetic analyses of major human joint motions. Topics include anthropometry, mechanical work and energy, muscle mechanics, synthesis of human movement, repetitive motion, and introduction to the design of prosthetic devices.

Biomedical Instrumentation I

This course focuses on the fundamental devices, circuitry, and techniques needed to acquire and preprocess biomedical signals. Operating principles of basic semiconductor devices as well as their application are explained. The electrical characteristics of diodes, photodiodes, Zener diodes, LED, regulators, and BJT transistors are covered. Switched mode power supplies are introduced as an application. Filtering principles and filer types are demonstrated in detail. Additionally, operational amplifiers are studied and used in multiple amplifier and filter circuits to preprocess signals. Non-ideal op amp properties are treated in sufficient depth to permit design of high gain circuits capable of handling small DC and low frequency biomedical signals.

Lasers: Medical Applications

Lasers have become increasingly utilized in many disciplines. This course will provide answers to questions such as: Why lasers? How do lasers work? How does laser light interact with living tissues and other materials? The course will demonstrate the basic mechanisms of light propagation in tissues and all laser tissue interactions (photo-chemical, photo-thermal, photo-ablation, and photo-mechanical interactions). The influence of laser wavelengths and pulse durations on the interaction process will be studied. In addition, diagnostic and therapeutic laser applications will be discussed. Selected laser medical applications in ophthalmology, urology, gynecology, and dentistry will be demonstrated throughout this course. Other interesting applications of lasers in data transmission, modulation, astronomy, and weaponry will also be illustrated.

System and Device for Tumor Characterization Using Nonlinear Elastography Imaging

US11090025B2

2021-08-01

The present invention provides a method and a device to image and characterize human tumors, and to classify the tumors as either malignant or benign. The method includes using a multi-compression technique upon the tissue or organ combined with a 3D ultrasound strain imaging of the compressed tissue or organ for acquiring raw data and analyzing the raw data using a computer processing unit equipped with a nonlinear biomechanical tissue model for tumor classification. A device is provided having a compression stage for delivering multi-compression with continuous force measurements, and a 3D ultrasound transducer strain imaging probe, wherein the imaging probe and the compression stage are in communication with a computer processing unit.

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Field of view enhancement via dynamic display portions

US10955678B2

2021-03-01

In certain embodiments, enhancement of a field of view of a user may be facilitated via one or more dynamic display portions. In some embodiments, one or more changes related to one or more eyes of a user may be monitored. Based on the monitoring, one or more positions of one or more transparent display portions of wearable device may be adjusted, where the transparent display portions enable the user to see through the wearable device. A live video stream representing an environment of the user may be obtained via the wearable device. A modified video stream derived from the live video stream may be displayed on one or more other display portions of the wearable device.

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Field of view enhancement via dynamic display portions

US20190227327A1

2019-07-25

In certain embodiments, enhancement of a field of view of a user may be facilitated via one or more dynamic display portions. In some embodiments, one or more changes related to one or more eyes of a user may be monitored. Based on the monitoring, one or more positions of one or more transparent display portions of a screen of wearable device may be adjusted, where the transparent display portions enable the user to see through the screen of the wearable device. A live video stream representing an environment of the user may be obtained via the wearable device. An enhanced video stream derived from the live video stream may be displayed on one or more other display portions of the screen of the wearable device.

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Visual enhancement for dynamic vision defects

US10409071B2

2019-09-10

In certain embodiments, live image data modifications may be facilitated for dynamic vision defects. In some embodiments, one or more eyes of a user may be monitored while a set of stimuli are displayed to the user. Feedback related to the set of stimuli may be obtained, where the feedback indicates (i) whether or how the user sees one or more stimuli of the set and (ii) one or more characteristics related to the eyes that occurred when such stimuli are displayed. A set of modification profiles associated with the user may be generated based on the feedback, where each modification profile of the set (i) is associated with eye-related characteristics and (ii) includes modification parameters to be applied to an image to modify the image for the user when eye-related characteristics of the user matches the associated eye-related characteristics.

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Field of view enhancement via dynamic display portions for a modified video stream

US10481402B1

2019-11-19

In certain embodiments, enhancement of a field of view of a user may be facilitated via one or more dynamic display portions. In some embodiments, one or more changes related to one or more eyes of a user may be monitored. Based on the monitoring, one or more positions of one or more transparent display portions of wearable device may be adjusted, where the transparent display portions enable the user to see through the wearable device. A live video stream representing an environment of the user may be obtained via the wearable device. A modified video stream derived from the live video stream may be displayed on one or more other display portions of the wearable device.

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Vision defect determination and enhancement using a prediction model

US10389989B2

2019-08-20

In certain embodiments, enhancement of a vision of a user may be facilitated. In some embodiments, a visual test presentation including a set of stimuli may be provided to a user. Feedback related to the set of stimuli may be obtained during the visual test presentation. The feedback may be provided to a prediction model, and the prediction model may be configured based on the feedback. Subsequent to the configuring of the prediction model, live video stream data, eye characteristic information, or other information may be provided to the prediction model to obtain a set of modification parameters. An enhanced image may be generated and displayed to the user based on the live video stream and the set of modification parameters.

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Vision defect determination and enhancement using a prediction model

US10485421B1

2019-11-26

In certain embodiments, enhancement of a vision of a user may be facilitated. In some embodiments, a visual test presentation including a set of stimuli may be provided to a user. Feedback related to the set of stimuli may be obtained during the visual test presentation. The feedback may be provided to a prediction model, and the prediction model may be configured based on the feedback. Subsequent to the configuring of the prediction model, live video stream data, eye characteristic information, or other information may be provided to the prediction model to obtain a set of modification parameters. A modified version of the live video stream data may be generated and displayed to the user based on the live video stream and the set of modification parameters.

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Solution for Non-invasive Breast Tissue Classification using Ultrasound Imaging

TIEC £1 million EGP

Co-PI Egypt 2017

Biodegradable albumin-based composites for suture production in tissue engineering applications

1. Mohamed A. Naser, Ahmed M. Sayed, Wael A. Moeaz, and Mohamed Tariq El- Waqad, Mohamed S. Abdo

April 2024 Recent advancements in the field of biomedical engineering have underscored the pivotal role of biodegradable materials in addressing the challenges associated with tissue regeneration therapies. The spectrum of biodegradable materials presently encompasses ceramics, polymers, metals, and composites, each offering distinct advantages for the replacement or repair of compromised human tissues. Despite their utility, these biomaterials are not devoid of limitations, with issues such as suboptimal tissue integration, potential cytotoxicity, and mechanical mismatch (stress shielding) emerging as significant concerns. To mitigate these drawbacks, our research collective has embarked on the development of protein-based composite materials, showcasing enhanced biodegradability and biocompatibility. This study is dedicated to the elaboration and characterization of an innovative suture fabricated from human serum albumin through an extrusion methodology. Employing a suite of analytical techniques—namely tensile testing, scanning electron microscopy (SEM), and thermal gravimetric analysis (TGA)—we endeavored to elucidate the physicochemical attributes of the engineered suture. Additionally, the investigation extends to assessing the influence of integrating biodegradable organic modifiers on the suture's mechanical performance. Preliminary tensile testing has delineated the mechanical profile of the Filament Suture (FS), delineating tensile strengths spanning 1.3 to 9.616 MPa and elongation at break percentages ranging from 11.5 to 146.64%. These findings illuminate the mechanical versatility of the suture, hinting at its applicability across a broad spectrum of medical interventions. Subsequent analyses via SEM and TGA are anticipated to further delineate the suture’s morphological features and thermal resilience, thereby enriching our comprehension of its overall performance characteristics. Moreover, the investigation delves into the ramifications of incorporating biodegradable organic constituents on the suture's mechanical integrity. Collectively, the study not only sheds light on the mechanical and thermal dynamics of a novel suture material derived from human serum albumin but also explores the prospective enhancements afforded by the amalgamation of biodegradable organic compounds,

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A comparison of measurements based on visual field testing with a novel algorithm on an augmented reality headset to standard automated perimetry

Catherine Johnson, Ahmed M. Sayed, John McSoley, Mary Durbin, Rashed Kashem, Alexandra Nicklin, Valeria Lopez, Georgeana Mijares, Michael Chen, Abdulla Shaheen, Steven Segarra, Christian Andres Duque, Mohamed Abou Shousha

May 2023 This study of inter-test comparability of a novel visual field application installed on an augmented-reality portable headset and Humphrey field analyzer Swedish interactive thresholding algorithm (SITA) Standard visual field test demonstrates the excellent correlation of mean deviation (MD) and mean sensitivity (MS).

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Correcting Higher Order Aberrations Using Image Processing

Olga Jumbo, Shihab Asfour, Ahmed M. Sayed, Mohamed Abdel-Mottaleb

January 2021 Higher Order Aberrations (HOAs) are complex refractive errors in the human eye that cannot be corrected by regular lens systems. Researchers have developed numerous approaches to analyze the effect of these refractive errors; the most popular among these approaches use Zernike polynomial approximation to describe the shape of the wavefront of light exiting the pupil after it has been altered by the refractive errors. We use this wavefront shape to create a linear imaging system that simulates how the eye perceives source images at the retina. With phase information from this system, we create a second linear imaging system to modify source images so that they would be perceived by the retina without distortion. By modifying source images, the visual process cascades two optical systems before the light reaches the retina, a technique that counteracts the effect of the refractive errors. While our method effectively compensates for distortions induced by HOAs, it also introduces blurring and loss of contrast; a problem that we address with Total Variation Regularization. With this technique, we optimize source images so that they are perceived at the retina as close as possible to the original source image. To measure the effectiveness of our methods, we compute the Euclidean error between the source images and the images perceived at the retina. When comparing our results with existing corrective methods that use deconvolution and total variation regularization, we achieve an average of 50% reduction in error with lower computational costs.

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Mobility improvement of patients with peripheral visual field losses using novel see-through digital spectacles

Ahmed M. Sayed, Mohamed Abou Shousha, MD Baharul Islam, Taher K. Eleiwa, Rashed Kashem, Mostafa Abdel-Mottaleb, Eyup Ozcan, Mohamed Tolba, Jane C. Cook, Richard K. Parrish II

2020 Purpose: To evaluate see-through Augmented Reality Digital spectacles (AR DSpecs) for improving the mobility of patients with peripheral visual field (VF) losses when tested on a walking track.

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Expansion of Peripheral Visual Field with Novel Virtual Reality Digital Spectacles

Ahmed M Sayed, Mostafa Abdel-Mottaleb, Rashed Kashem, Vatookarn Roongpoovapatr, Mohamed Abdel-Mottaleb, Richard K Parrish II, Mohamed F Abou Shousha

2020 Purpose: To examine an image remapping method for peripheral visual field (VF) expansion with novel virtual reality digital spectacles (DSpecs) to improve visual awareness in glaucoma patients.

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Quantitative Assessment of Gingival Inflammation Using HighResolution Ultrasound Ex Vivo

This study investigates the feasibility of using high-resolution ultrasound imaging echogenicity to quantitatively diagnose gingival inflammation. Gingival samples were extracted from the study participants during gingivectomy procedures. Ultrasound mechanical scanning of the samples was immediately conducted ex-vivo to render cross-sectional images of high resolution, at different locations. Samples’ histological preparation and analysis was followed after performing ultrasound imaging.

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Automatic Segmentation of Corneal Microlayers on Optical Coherence Tomography Images

To propose automatic segmentation algorithm (AUS) for corneal microlayers on optical coherence tomography (OCT) images.

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Automatic Classification of Breast Tumors Using Features Extracted from Magnetic Resonance Images

Breast cancer is considered as the second leading cause of cancer deaths among women in the United States. Early detection of cancer is crucial in order to reduce its negative effects.

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3-D Visualization and Non-linear Tissue Classification of Breast Tumors Using Ultrasound Elastography In Vivo

The goal of the study described here was to introduce new methods for the classification and visualization of human breast tumors using 3-D ultrasound elastography. A tumor's type, shape and size are key features that can help the physician to decide the sort and extent of necessary treatment.

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