Free Visual Prosthesis Essay Sample
Introduction
The social significance of the current research, which is oriented to designing and improving the technical and ergonomic characteristics of a visual prosthesis, tends to rise nowadays. As it aims at restoring the vision of those individuals who suffer from partial and total blindness, the number of potential recipients of such services is considerable. However, the successful implementation of this project is associated with numerous explicit and implicit challenges. On the one hand, there is a need for optimizing interactions between the eye and the ophthalmic nerve with the electronic signals incorporated into the device. Thus, it includes the corresponding biological and technological considerations.
On the other hand, the working principle of a visual prosthesis should provide the corresponding care of vision through achieving the proper balance between its inputs, outputs, and processing abilities. There are different approaches to the solution of the outlined issue. It is also necessary to evaluate the possibilities to develop further the existing device in the context of including the ability to provide the live video stream similar to the perceptions of the real eye. There are also numerous design, manufacturing, and constraints issues related to the outlined device. Although the development of a visual prosthesis and its further improvement constitute a challenging task, the existing technological opportunities and professional qualification of various professionals contribute to the high likelihood of the substantial improvements in this sphere in the nearest future.
Interaction of Eye and Ophthalmic Nerve with Electronic Signals
The effective fulfillment of its key functions by the visual prosthesis is possible only if the proper interactions between the eye and ophthalmic nerve with the corresponding electronic signals are achieved. The selected types of electronic signals are based on the close examination of the real eye functioning under the normal conditions. It includes the key role of photoreceptor cells in converting into the electrical and chemical signals; ultimately, the brain receives the visual signal. The visual prosthesis should assist in utilizing the adequate electronic signals for fulfilling the similar function.
In particular, it enables stimulating bipolar cells with the proportional impact on the ophthalmic nerve. In some difficult cases, when the patient’s ophthalmic nerve does not function properly, it is possible to utilize electronic signals for stimulating the brain directly. However, such direct stimulation is associated with additional difficulties, and it is used only in those cases when the existing technological opportunities or the patient’s health conditions do not allow affecting the ophthalmic nerve.
The recent clinical research demonstrates the effectiveness of utilizing electronic signals for restoring some functions even among blind patients. The visual prosthesis enables people recognizing and comprehending the location of different objects. Patients’ ability to orient themselves in the new environment tends to improve. In some cases, patients may even become able to perform the basic reading tasks. In general, it is crucial to consider the health conditions of each particular patient to determine the appropriate type and intensity of the electronic signal.
Working Principle of Visual Prosthesis
Although there are several approaches towards organization of the visual prosthesis functioning, it is possible to outline the major components of its working principle, including the corresponding inputs, outputs, and processing abilities. The major inputs refer to assessing the visual space for a particular patient and those areas (the ophthalmic nerve, brain, etc.) that should be stimulated. Moreover, as the interventions impact the entire patient’s health system, it is necessary to measure the inputs, their dynamics, and intensity on the regular basis. When the visual prosthesis has obtained the inputs, it transforms them into the outputs according to the designed program or algorithm.
The outputs include the electrical signals that assist the ophthalmic nerve and the patient’s brain to obtain the necessary information regarding the external world. The outputs enable transforming patients’ visual space in a way that is objectively required by their health conditions. Phosphenes may also be generated in order to restore the balance of the nervous system and ensure the adequate reactions to the provided impulses. In general, the outputs try to liquidate the gap between the possibilities of the real eye and those of the visual prosthesis. The examination of the patient’s brain activity is necessary for assessing the effectiveness of the introduced outcomes and the usefulness of initiating the urgent adjustments.
However, the major element in this context refers to the visual prosthesis’ processing abilities. In fact, the existing technological possibilities should allow establishing the proper relationships between inputs and outputs as well as minimize the time for transforming the visual space and sending the proper electronic signals. The implanted electronics enable regulating power as well as controlling the direction and intensity of the impulses. Modern versions of the visual prosthesis include the sophisticated electronic circuitry. It contributes to a more realistic presentation of the external reality impacting the patient’s systems and brain functions.
Digital camera technologies that are used for obtaining the initial information for its subsequent transmission to the patient’s brain. It is possible to provide the timely adjustments in relation to the patient’s aesthetic preferences and sensitivity. It should correspond to the general patterns demonstrated by his nervous system. Any deviation may lead to additional time needed for grasping the information and providing the required response as well as activating the expected reactions. The dynamic range of interventions depends on the specific type of strategy and the visual prosthesis’ configurations.
There are two major methods used for transmitting electronic signals through the patient’s skin. These include radio frequency telemetry and percutaneous connectors, and they have their corresponding strengths and weaknesses. Percutaneous connectors are more robust and do not require complementary devices for their functioning. However, such a method may lead to the growing likelihood of different infections due to the substantial number of electrodes and their mutual impact. In some modifications, cochlear implants may be used for supporting the general effect of connectors. Radio frequency telemetry enables sending and receiving signals without breaking the skin, and it constitutes a considerable advantage, especially in the context of the long-term trends in this field. Moreover, various optically transparent options are used for reaching the retina. The target cells should be stimulated with the help of a laser incorporated in glasses. This system enables transmitting both power and the needed information to the brain. The existing technologies assist in specifying those target cells that should be stimulated for sending and receiving the specific types of information.
The visual prosthesis’ working principle also includes the multichannel stimulators that impact consistent phosphenes through electrodes. It is also necessary to address the serious safety concerns in order to avoid the potential health damage that may occur due to the improper functioning of the electrode interface. Therefore, the capacity and power issues should be addressed in advance to eliminate the possibility of any negative health effects or tissue damages under any conditions.
The interface to the nervous system is the next crucial element of the working principle. It creates the basis for the consistent and productive electrical stimulation. The advancements, which are helpful in understanding implications of the electrochemical processes during the last 40 years, enable designing the effective interventions as well as maintaining the integrity of the epithelial cell layer. The current research in this field mostly refers to maximizing biocompatibility of all the elements and maximizing the actual health outcomes with the minimum degree of risks. Thus, the working principle utilized in the visual prosthesis is complex as it includes numerous interrelated elements.
Possibilities of Developing Fully-Functional Device
Despite the current progress in the sphere of such technologies, the visual prosthesis still cannot offer the perfect substitute for the real eye. In fact, it can assist patients in obtaining some visual information and adjusting their behavior with the help of electronic signals or other methods. However, the quality of obtained information is still low in comparison with the real eye. Therefore, the major focus of the future research is designing the multi-functional recording and transmitting device that provides a live video stream and imitates closely the functioning of the real eye.
In general, the current trends indicate the possibility of designing such a device in the long run if several intermediate objectives are met. First, it is necessary to increase the phosphene reliability. The current distance between the electrodes and target cells is not optimal, and additional research may be needed for optimizing the distance and the impact of the electrodes. In addition, the current methods often lead to the situation when not only target cells are affected. It disrupts the functioning of the nervous system and the brain. Therefore, the integrated device should be able to identify and affect precisely the target cells without any negative secondary effects.
Second, it may be reasonable to increase the stimulation frequency in order to facilitate the positive processes of restoring health functions. The modifications of the existing neural networks can allow initiating interventions associated with the maximum frequency. Third, the fully-functional device should possess the improved spatial resolution. It is necessary for analyzing the patient’s health dynamics and the precision of interventions in the most correct way. It may be expected that the further technological progress will enable achieving the desired resolution in the nearest future.
Four, it is necessary to introduce the integrated and standardized assessment of the patients’ health indicators. In particular, the parameters, such as form vision, spatial mapping, the reported outcomes, and even daily activities, should be considered while determining the utility of the new devices. The complex assessments will also outline the precise spheres for the future research and technological development. Five, the future device should provide the proportional compensation to the neural network after sending the electronic impulses. Currently, some problems in this regard exist as well as regarding optimizing the relationships between the electronic stimulation and the subsequent neural response.
Finally, both visual resolution and visual field size of the new device should be maximized. It represents a serious challenge as it is typically necessary to find the proper balance between these two components. The multi-functional device should demonstrate the highest acuity with the maximum area of restored vision. The device should have a positive impact on the rates of degeneration. Human cells have the potential for restoring their natural qualities and characteristics, but the current technologies have a negative effect on degeneration. Therefore, it is necessary to consider this situation closely and create the optimal conditions for the given process. If this objective is addressed properly, the intensity of stimulation can be declined gradually according to the degeneration trends observed in relation to a specific patient.
Thus, the development of the multi-functional device that will serve as a perfect substitute of the real eye is possible in the future. However, it requires addressing the above-mentioned challenges in the consistent manner.
Design, Manufacturing, and Implementing Constraints
Although it is possible to produce the multi-functional device from a theoretical perspective, the practical implementation of such a project is associated with numerous challenges. The major design constraints refer to the need for integrating the device into the human system with the minimum negative impact on other functions. The optimal design should presuppose the natural extension of the patient’s functions through the corresponding stimulation of the major brain zones and target cells. The design considerations should be integrated closely into the overall system of maintaining visual acuities and the ability to implement the timely adjustments to the needs of a particular patient. It means that the direction of electronic signals as well as their intensity should be regulated due to the regular monitoring of the patient’s health conditions.
The manufacturing constraints include physical and technological aspects that cannot be neglected while developing the multi-functional device. The current pitch constraint is around 50 μm for different types of stimulation. As the multi-functional device may require more sophisticated techniques and moving beyond the outlined pitch, the current focusing and steering methods should be used. In general, the present state of technological knowledge allows implementing such methods; however, it is necessary to apply them correctly to the specific challenges in the context of patients’ health conditions and functions.
The implementation constraints include the need for relying on the load testing for assessing patients’ performance measures as well as considering the economic benefits of the large-scale distribution and utilization of the device. The current performance measures should serve as the direction of further implementation trends. In particular, if some health needs are not addressed properly or additional risks are identified, the timely adjustments in the implementation strategy are necessary. Economic benefits and analysis are required for assessing the possibility of generating positive financial results as well as potential need for searching other funds from the third parties. Moreover, the device usage by all the patients should be documented to identify any deviations from the prescribed procedures. Consequently, the implementation of the device distribution may also be revised. In general, it is necessary to utilize the systematic approach for minimizing the scope of the existing restraints and contributing to the maximum possible satisfaction of the patients’ needs.
Conclusion
To summarize, there are numerous urgent issues related to the visual prosthesis. The recent progress in this field indicates the possibility of restoring basic functions and assisting patients with partial or total blindness in orienting in the new environment, comprehending the location of external objects, and performing some reading tasks. The visual prosthesis utilizes the electronic signals for stimulating the corresponding target cells and brain areas. Consequently, it contributes to the proper transformation of the visual space and more objective comprehension of the external reality.
The artificial device utilizes a variety of inputs for achieving the desired outputs according to the existing algorithms. The processing abilities are based on the latest technological opportunities and the available means for analyzing inputs and transforming them into the desired reaction due to the electronic impulses and other tools. The further development of the research in this field will be oriented to developing a multi-functional recording and transmitting device that may perform the same functions as the real eye. There exists theoretical possibility of such technological advancement although it presupposes addressing a variety of key challenges from several interrelated areas. It is also necessary to consider the major design, manufacturing, and implementing constraints to demonstrate the steady progress in this field. However, the consistent and systematic approach may lead to the positive long-term results.