Article
Optics
Ning Xi, Jiaxun Ye, Chao Ping Chen, Qiang Chu, Haiyang Hu, Seak Pang Zou
Summary: We propose an implantable metaverse with retinal prostheses that work in tandem with bionic vision processing. Our approach differs from conventional retinal prostheses by rearranging electrodes to match the distribution of ganglion cells. To emulate human vision, we develop a scheme for bionic vision processing that visualizes monocular image, binocular image fusion, and parallax-induced depth map on a three-dimensional eye model.
Article
Clinical Neurology
Avi Caspi, Michael P. Barry, Uday K. Patel, Michelle Armenta Salas, Jessy D. Dorn, Arup Roy, Soroush Niketeghad, Robert J. Greenberg, Nader Pouratian
Summary: The study focuses on evaluating the impact of eye movements on phosphene locations elicited by electrical stimulation of the visual cortex to restore sight in blind subjects. Results show that eye movements significantly affect the perceived location of cortical stimulation-evoked phosphenes, even after prolonged blindness. By accounting for eye positions and remapping responses, researchers can mimic retinal mapping to improve visual restoration outcomes.
Article
Engineering, Electrical & Electronic
Abraham Akinin, Jeremy M. Ford, Jiajia Wu, Chul Kim, Hiren D. Thacker, Patrick P. Mercier, Gert Cauwenberghs
Summary: This article introduces an inductively powered wireless SoC for an electrically controlled, optically addressed retinal prosthetic system, achieving reduced thermal dissipation near sensitive retinal tissue and charge-balanced stimulation control.
IEEE JOURNAL OF SOLID-STATE CIRCUITS
(2021)
Article
Biochemistry & Molecular Biology
Alessandro Bellapianta, Ana Cetkovic, Matthias Bolz, Ahmad Salti
Summary: Despite significant progress in modern medicine, millions of people with retinal dystrophies or age-related diseases still suffer from severe visual impairment. Reprogramming somatic cells into induced pluripotent stem cells and advancements in electronic retinal prosthesis technology offer promising opportunities for studying and treating these conditions.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Review
Ophthalmology
Daniel Caravaca-Rodriguez, Susana P. Gaytan, Gregg J. Suaning, Alejandro Barriga-Rivera
Summary: Retinal degenerative diseases result in vision loss due to neural rewiring cascade. Activating retinal neurons via implants faces challenges of unselective activation patterns and pre-existing neural rewiring. Modulating neural rewiring may be crucial for improving artificial vision and neurorehabilitation strategies.
INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE
(2022)
Article
Biochemistry & Molecular Biology
Carey Y. L. Huh, Henri Leinonen, Taylor Nakayama, Julia R. Tomasello, Jianye Zhang, Jack Zeitoun, John P. Peach, Maximilian Halabi, Jianying Z. Kiser, Krzysztof Palczewski, Philip D. Kiser, Sunil P. Gandhi
Summary: This study found that adult mice can recover visual responsiveness in the primary visual cortex following the correction of retinal defects through retinoid treatment. The treatment increases the number and amplitude of visually responsive neurons and restores the balance of eye-specific responses in the cortex. Additionally, it rescues the modulation of cortical responses by arousal.
Article
Pharmacology & Pharmacy
Jin Liu, Jessica Kwan Wun Tsang, Frederic Khe Cheong Fung, Sookja Kim Chung, Zhongjie Fu, Amy Cheuk Yin Lo
Summary: This study comprehensively analyzed the role of retinal microglia in retinopathy of prematurity (ROP), and found that the activation of retinal microglia was closely associated with increased retinal microglia and vessels in the process of vascular abnormalities. Additionally, the pharmacological inhibition of retinal microglia exacerbated the retinal vascular consequences in ROP.
FRONTIERS IN PHARMACOLOGY
(2022)
Article
Ophthalmology
Huizhuo Xu, Xingwu Zhong, Changlin Pang, Jing Zou, Wangling Chen, Xianggui Wang, Shanxiang Li, Yuntao Hu, Didier S. Sagan, Philip T. Weiss, Yangyi Yao, Jiayi Xiang, Margot S. Dayan, Mark S. Humayun, Yu-Chong Tai
Summary: The study demonstrated significant improvement in visual performance and relative safety of the IMIE 256 system in comparison to baseline or when the system was turned off. Further clinical trials are needed to validate these results, with observed adverse events mainly related to expected postoperative healing processes and serious adverse events successfully resolved through surgery.
TRANSLATIONAL VISION SCIENCE & TECHNOLOGY
(2021)
Article
Medicine, General & Internal
Sophia Sidhu, Patrice J. Persad, Byron L. Lam, Kasey L. Zann, Ninel Z. Gregori
Summary: The study aims to assess the assistive devices used by patients with IRDs, the difficulties they face despite these devices, and their recommendations for a future visual prosthesis. An online survey was conducted with IRDs patients, and it was found that participants reported continued difficulty with ADLs despite current assistive devices.
JOURNAL OF CLINICAL MEDICINE
(2023)
Article
Engineering, Biomedical
Matthew J. Bryan, Linxing Preston Jiang, Rajesh P. N. Rao
Summary: This study proposes a device called a 'neural co-processor' which uses artificial neural networks and deep learning to learn optimal closed-loop stimulation policies and adapt them as the brain and sensors change. Computer simulations demonstrate the ability of the neural co-processor to recover healthy function after different lesions.
JOURNAL OF NEURAL ENGINEERING
(2023)
Article
Behavioral Sciences
Amber Maimon, Or Yizhar, Galit Buchs, Benedetta Heimler, Amir Amedi
Summary: The paper discusses the unique phenomenological experience of a man who became blind in adulthood and underwent training with both an Argus II retinal prosthesis and the EyeMusic sensory substitution device. The man reports that the sensory substitution device provided a richer and more natural perceptual experience compared to the retinal prosthesis. Long-term use of the sensory substitution device resulted in a higher level of automaticity. The combination of both devices also enhanced the user's subjective visual experience.
Article
Ophthalmology
Samuel A. Titchener, Jeroen Goossens, Jessica Kvansakul, David A. X. Nayagam, Maria Kolic, Elizabeth K. Baglin, Lauren N. Ayton, Carla J. Abbott, Chi D. Luu, Nick Barnes, William G. Kentler, Mohit N. Shivdasani, Penelope J. Allen, Matthew A. Petoe
Summary: Gaze-based phosphene mapping is a viable alternative to conventional finger-based mapping, but may not be suitable for all subjects.
TRANSLATIONAL VISION SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
James M. Begeng, Wei Tong, Blanca del Rosal, Michael Ibbotson, Tatiana Kameneva, Paul R. Stoddart
Summary: Patients with photoreceptor degeneration-caused blindness can partially regain vision through artificial stimulation of surviving retinal ganglion cells (RGCs). Nanoparticle-based optical sensors, specifically nanoparticle-enhanced infrared neural modulation (NINM), show potential in stimulating and inhibiting RGCs, which is important for modulating different types of RGCs. Gold nanorods with tunable absorption in the near-infrared range could be well-suited for retinal prosthesis applications but have not been demonstrated in RGCs before.
Article
Chemistry, Analytical
Chenlin Xu, Gengxi Lu, Haochen Kang, Mark S. Humayun, Qifa Zhou
Summary: This paper introduces a novel design and simulation of a non-invasive ultrasonic retinal stimulation device, which can acoustically couple with the eye via the tear film and trigger the activities of retinal neurons with high spatial-temporal resolution. Compared with other retinal prostheses, this ultrasound ring array is shown to be practical and safe.
Article
Engineering, Biomedical
Zhijie Charles Chen, Bing-Yi Wang, Anna Kochnev Goldstein, Emma Butt, Keith Mathieson, Daniel Palanker
Summary: The study aims to improve the shaping of electric fields for PRIMA. A new computational framework, RPSim, is used to predict stimulus strength and contrast of the retina's electric field with different pixel designs and stimulation patterns. The results show that using monopolar pixels and pillar electrodes can enhance stimulus strength and contrast, potentially achieving higher resolution in some patients.
JOURNAL OF NEURAL ENGINEERING
(2022)
Article
Engineering, Biomedical
Reem M. Almasri, Amr Al Abed, Yuan Wei, Han Wang, Josiah Firth, Laura A. Poole-Warren, Francois Ladouceur, Torsten Lehmann, Nigel H. Lovell
Summary: This study investigates the impedance properties of optrode technology for biopotential recording. The results show that the liquid crystals in the optrode platform have higher input impedance values suitable for voltage sensing. The optrode system automatically scales the input impedance to maintain a relatively constant ratio, allowing for high spatial-resolution recordings regardless of the size of the recording site.
IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING
(2022)
Article
Engineering, Biomedical
Masoud Fetanat, Michael Stevens, Pankaj Jain, Christopher Hayward, Erik Meijering, Nigel H. Lovell
Summary: In this study, an improved Harris Hawks optimizer algorithm (HHO+) and a novel fully Elman neural network (FENN) were proposed for the classification of abnormal and normal pulmonary arterial wedge pressure (PAWP) using a convolutional neural network (CNN). The results showed that the proposed CNN-FENN-HHO+ method outperformed other methods in classification performance, which may help reduce the mortality rate of patients with heart failure.
IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING
(2022)
Article
Computer Science, Artificial Intelligence
Xiaoou Ding, Hongzhi Wang, Jiaxuan Su, Muxian Wang, Jianzhong Li, Hong Gao
Summary: This paper studies the method of multiple data cleaning for incomplete and inconsistent data, proposing a four-step framework called Imp3C. It uses a currency determining method and a consistency distance metric to repair dirty data. Experiments demonstrate that Imp3C outperforms existing methods in data repairing.
IEEE TRANSACTIONS ON KNOWLEDGE AND DATA ENGINEERING
(2022)
Article
Engineering, Biomedical
Abdulrahman Alqahtani, Amr Alabed, Yousef Alharbi, Mohsen Bakouri, Nigel H. Lovell, Socrates Dokos
Summary: This study compares the classical cable equation and the varying-radius cable equation for modeling nerve fibers under different electrical stimulation protocols. The results show that the classical equation has a significant error in simulating intracellular neural electrical stimulation, while the difference between the two equations is smaller in the case of extracellular stimulation.
INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING
(2022)
Article
Engineering, Biomedical
Michael L. Italiano, Tianruo Guo, Nigel H. Lovell, David Tsai
Summary: This study developed an anatomically accurate 3D model of RGC populations within the human central retina and demonstrated the potential for an epiretinal hexapolar configuration to achieve consistent, spatially confined retinal responses even within the unique and neuron-dense foveal region.
JOURNAL OF NEURAL ENGINEERING
(2022)
Article
Engineering, Biomedical
Ariyamehr Rezaei, Michael C. C. Stevens, Ahmadreza Argha, Alessandro Mascheroni, Alessandro Puiatti, Nigel H. H. Lovell
Summary: In this study, an unobtrusive monitoring system using infrared technology was developed to accurately detect human activities, locations, and critical activities such as falling and lying on floor.
IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING
(2023)
Article
Engineering, Electrical & Electronic
Ariyamehr Rezaei, Alessandro Mascheroni, Michael C. Stevens, Reza Argha, Michela Papandrea, Alessandro Puiatti, Nigel H. Lovell
Summary: As the population ages, wearable devices offer a solution for unobtrusively detecting falls. The millimeter-wave radar technology was used in this study to collect data from healthy young volunteers. Different classifiers, including multilayer perceptron, random forest, k-nearest neighbor, and support vector machine, were applied to the extracted features. Additionally, a convolutional neural network based on deep learning was proposed. Results showed that the random forest classifier achieved the best accuracy, and the CNN model performed slightly better, suggesting the feasibility of using mmWave radar for unobtrusive fall detection.
IEEE SENSORS JOURNAL
(2023)
Article
Engineering, Biomedical
Shaheen Hasmat, Nigel H. Lovell, Tsu-Hui (Hubert) Low, Jonathan R. Clark
Summary: Facial nerve paralysis (FNP) can lead to corneal exposure due to lack of blinking, but the implantable solution called Bionic lid implant for natural closure (BLINC) solves this problem by using an electromagnetic actuator and an eyelid sling. This study focuses on the device's biocompatibility and describes its evolution through prototypes to address these issues. The key components of the device include the actuator, electronics with energy storage, and an induction link for wireless power transfer. Testing in synthetic or cadaveric models ensures the final prototype is suitable for acute and chronic animal trials.
MEDICAL ENGINEERING & PHYSICS
(2023)
Article
Engineering, Electrical & Electronic
Yuan Wei, Han Wang, Amr Al Abed, Reem M. Almasri, Xinyue Lei, Josiah Firth, Leonardo Silvestri, Francois Ladouceur, Torsten Lehmann, Nigel H. Lovell
Summary: This study proposes a design for a bi-directional optical-electrode or 'optrode' that can interface with peripheral nerves and brain-machine interfaces. The principle of operation is explained, including the ability to provide biphasic stimulus and charge balancing functionalities. The prototype chip is fabricated, characterized, and tested both in vivo and ex vivo, successfully demonstrating its capability to stimulate and record from the rabbit sciatic nerve. The experiment also validates the charge-balancing effect of a discrete component circuit.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Engineering, Biomedical
Yuyang Xie, Peijun Qin, Tianruo Guo, Amr Al Abed, Nigel H. Lovell, David Tsai
Summary: A computational toolkit was developed to create nerve stimulation models and study fiber responses under different electrode arrangements and stimulation waveforms. The toolkit allows bi-directional transfer of results and provides an agile and efficient design method for improving the design of intrafascicular implants.
JOURNAL OF NEURAL ENGINEERING
(2023)
Article
Chemistry, Analytical
Kefan Zhu, Phuoc Thien Phan, Bibhu Sharma, James Davies, Mai Thanh Thai, Trung Thien Hoang, Chi Cong Nguyen, Adrienne Ji, Emanuele Nicotra, Hung Manh La, Tat Thang Vo-Doan, Hoang-Phuong Phan, Nigel H. Lovell, Thanh Nho Do
Summary: This paper presents a smart textile-actuated spine assistance robotic exosuit (SARE) that seamlessly conforms to the back and allows for free movement, while also monitoring and rectifying human posture. Experimental results with human subjects show that the SARE can effectively reduce muscle strain, electromyography signals, and metabolic energy cost associated with repetitive lifting tasks.
Article
Clinical Neurology
Fiona L. Knapman, E. Myfanwy Cohen, Tom Kulaga, Nigel Lovell, Leszek Lisowski, Simon Mcmullan, Peter G. R. Burke, Lynne E. Bilston
Summary: This study proposes a novel optogenetics-based therapy for obstructive sleep apnea (OSA) and demonstrates its feasibility using a rodent model. The therapy involves stimulating upper airway muscle contractions in response to light. The results show that muscle-specific promoter-driven optogenetic muscle activation can effectively restore muscle activity and induce airway dilation.
Article
Oncology
Reza Ghamsari, Joseph Rosenbluh, A. Vipin Menon, Nigel H. Lovell, Hamid Alinejad-Rokny
Summary: Enhancers serve as logic gates of gene expression regulation and their malfunction is associated with various diseases. The functional validation of enhancer elements is therefore crucial in genomics research. Recent advancements in technology have enabled researchers to perturb enhancers and examine their impact on nearby gene expression. This review summarizes the progress made in experimental and computational methods, providing researchers with promising tools to uncover enhancer-phenotype relationships and gain mechanistic insights into diseases.
Review
Engineering, Biomedical
Reem M. Almasri, Francois Ladouceur, Damia Mawad, Dorna Esrafilzadeh, Josiah Firth, Torsten Lehmann, Laura A. Poole-Warren, Nigel H. Lovell, Amr Al Abed
Summary: Optrode arrays utilize light to modulate biological tissues and transduce bioelectrical signals into the optical domain. This review provides an overview of devices and material systems that use light for electrophysiology recording and stimulation.
APL BIOENGINEERING
(2023)
Article
Engineering, Biomedical
Chi Cong Nguyen, Timotius Teh, Mai Thanh Thai, Phuoc Thien Phan, Trung Thien Hoang, James Davies, Hoang-Phuong Phan, Chun H. Wang, Nigel H. Lovell, Thanh Nho Do
Summary: Minimally invasive surgery has been effective for cardiovascular diseases and gastrointestinal cancers. Soft robotic catheters using soft materials have gained attention for their ability to navigate complex anatomical structures. However, current systems have limitations due to rigid mechanisms and insufficient forces. New soft robotic catheters with bidirectional bending motion and spiral shapes have been introduced to address these challenges. They offer quicker and more accurate manipulation for cardiac and GI interventions, enhancing patient outcomes.
IEEE TRANSACTIONS ON MEDICAL ROBOTICS AND BIONICS
(2023)
