{"id":{"repo_id":"auckland-ms","oai_identifier":"oai:researchspace.auckland.ac.nz:2292/69319"},"canonical_url":"https://search.dev.ndltd.org/etd/auckland-ms/oai:researchspace.auckland.ac.nz:2292/69319","repository":{"repo_id":"auckland-ms","name":"University of Auckland","base_url":"https://researchspace.auckland.ac.nz/server/oai/request"},"display":{"title":"Smart Ocular Implant for Monitoring IOP in Glaucoma Patients","abstract":"Glaucoma is often called the ’thief of sight’ or the ’silent blinding eye disease’. As the world’s second most blinding eye disease and the number one irreversible eye disease, numerous studies have shown that pathological IOP is a significant risk factor. A single clinical examination of vision cannot detect an insidious increase in IOP. Therefore, long-term, uninterrupted IOP measurement is of great importance for the early diagnosis of glaucoma and individual monitoring and IOP control of glaucoma patients. Implantable IOP testing devices have been developed to perform long-term IOP measurement tasks effectively. Today’s implantable IOP devices mainly use capacitive IOP sensors as the primary operating device for remote excitation and data acquisition. Most of the research has focused on developing sensors, mainly using metal layers as the conductive plates of a capacitive sensor. Large stationary devices such as network analysers are typically used for data acquisition. The overall system lacks the original purpose of mobility and simplicity. This thesis presents an outline for an implantable IOP detection device, for which the various subsystems are designed and analysed to simplify the system for long-term IOP measurement. Firstly, a remote excitation coil system is designed and analysed. A three-dimensional transmitter coil that can be attached to the frame of a spectacle is proposed. This transmitter coil is designed to maximise the magnetic coupling with a corresponding implanted sensor coil. A simple half-bridge inverter module is developed to drive the transmitter coil through a compensation network, thereby exciting the sensor coil. The design is optimised using simulations, and experimental results are provided to validate operation for various misalignment cases. Next, a novel receiver coil system is developed to extract the IOP through magnetic coupling with the sensor coil. To simplify the design of the IOP readout, the strong magnetic coupling between the receiver and transmitter coils is decoupled using an inductor pair. Through mathematical modelling and simulations of the structure, the operation of the decoupled mutual inductor pair is determined.The experiments verify that the receiver circuit can resolve changes in the IOP sensor signal using a simple rectifier circuit, reducing the complexity of conventional readout circuits. Misalignment cases are also analysed and discussed. Finally, this thesis proposes a new stretchable conductive film based implantable capacitive sensor for IOP measurements, by investigating the characteristic of suitable materials and structures. This capacitive sensor uses a planar structure and can be easily miniaturised further. Using a conductive film with excellent biocompatibility and as a drug-release component provides for the future use of automatic drug-release attached to IOP detection devices. A mathematical model of the structural mechanics and capacitance of the proposed sensor is presented, and simulations are carried out. A prototype has been built, and the simulation results are experimentally verified, including testing and analysing the reproducibility and consistency of the sensor. Suggested future research areas are identified.","abstract_html":"Glaucoma is often called the ’thief of sight’ or the ’silent blinding eye disease’. As the world’s second most blinding eye disease and the number one irreversible eye disease, numerous studies have shown that pathological IOP is a significant risk factor. A single clinical examination of vision cannot detect an insidious increase in IOP. Therefore, long-term, uninterrupted IOP measurement is of great importance for the early diagnosis of glaucoma and individual monitoring and IOP control of glaucoma patients. Implantable IOP testing devices have been developed to perform long-term IOP measurement tasks effectively. Today’s implantable IOP devices mainly use capacitive IOP sensors as the primary operating device for remote excitation and data acquisition. Most of the research has focused on developing sensors, mainly using metal layers as the conductive plates of a capacitive sensor. Large stationary devices such as network analysers are typically used for data acquisition. The overall system lacks the original purpose of mobility and simplicity. This thesis presents an outline for an implantable IOP detection device, for which the various subsystems are designed and analysed to simplify the system for long-term IOP measurement. Firstly, a remote excitation coil system is designed and analysed. A three-dimensional transmitter coil that can be attached to the frame of a spectacle is proposed. This transmitter coil is designed to maximise the magnetic coupling with a corresponding implanted sensor coil. A simple half-bridge inverter module is developed to drive the transmitter coil through a compensation network, thereby exciting the sensor coil. The design is optimised using simulations, and experimental results are provided to validate operation for various misalignment cases. Next, a novel receiver coil system is developed to extract the IOP through magnetic coupling with the sensor coil. To simplify the design of the IOP readout, the strong magnetic coupling between the receiver and transmitter coils is decoupled using an inductor pair. Through mathematical modelling and simulations of the structure, the operation of the decoupled mutual inductor pair is determined.The experiments verify that the receiver circuit can resolve changes in the IOP sensor signal using a simple rectifier circuit, reducing the complexity of conventional readout circuits. Misalignment cases are also analysed and discussed. Finally, this thesis proposes a new stretchable conductive film based implantable capacitive sensor for IOP measurements, by investigating the characteristic of suitable materials and structures. This capacitive sensor uses a planar structure and can be easily miniaturised further. Using a conductive film with excellent biocompatibility and as a drug-release component provides for the future use of automatic drug-release attached to IOP detection devices. A mathematical model of the structural mechanics and capacitance of the proposed sensor is presented, and simulations are carried out. A prototype has been built, and the simulation results are experimentally verified, including testing and analysing the reproducibility and consistency of the sensor. Suggested future research areas are identified.","abstract_has_math":false,"creators":["Xu, Qing"],"institution":"ResearchSpace@Auckland","degree_name":"PhD","degree_level":"Doctoral","degree_discipline":"Engineering","degree_department":null,"school":null,"contributors":[],"advisors":["Thrimawithana, Duleepa"],"committee_chairs":[],"committee_members":[],"year":2024,"date_issued":"2024","date_published":"2024","updated_at":"2026-07-24T01:07:07Z","subjects":[],"languages":[],"rights":["Items in ResearchSpace are protected by copyright, with all rights reserved, unless otherwise indicated."],"rights_urls":["https://researchspace.auckland.ac.nz/docs/uoa-docs/rights.htm"],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/2292/69319","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Thrimawithana, Duleepa"]},{"key":"dc:creator","label":"Author","values":["Xu, Qing"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2024-07-24T20:02:09Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2024-07-24T20:02:09Z"]},{"key":"dc:date.issued","label":"Date","values":["2024"]},{"key":"dc:publisher","label":"Institution","values":["ResearchSpace@Auckland"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Engineering"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Doctoral"]},{"key":"thesis:degree_name","label":"Degree Name","values":["PhD"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["The University of Auckland"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:rights","label":"Dc Rights","values":["Items in ResearchSpace are protected by copyright, with all rights reserved, unless otherwise indicated."]},{"key":"dc:rights.uri","label":"Rights URI","values":["https://researchspace.auckland.ac.nz/docs/uoa-docs/rights.htm"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://hdl.handle.net/2292/69319"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Glaucoma is often called the ’thief of sight’ or the ’silent blinding eye disease’. As the world’s second most blinding eye disease and the number one irreversible eye disease, numerous studies have shown that pathological IOP is a significant risk factor. A single clinical examination of vision cannot detect an insidious increase in IOP. Therefore, long-term, uninterrupted IOP measurement is of great importance for the early diagnosis of glaucoma and individual monitoring and IOP control of glaucoma patients. Implantable IOP testing devices have been developed to perform long-term IOP measurement tasks effectively. Today’s implantable IOP devices mainly use capacitive IOP sensors as the primary operating device for remote excitation and data acquisition. Most of the research has focused on developing sensors, mainly using metal layers as the conductive plates of a capacitive sensor. Large stationary devices such as network analysers are typically used for data acquisition. The overall system lacks the original purpose of mobility and simplicity. This thesis presents an outline for an implantable IOP detection device, for which the various subsystems are designed and analysed to simplify the system for long-term IOP measurement. Firstly, a remote excitation coil system is designed and analysed. A three-dimensional transmitter coil that can be attached to the frame of a spectacle is proposed. This transmitter coil is designed to maximise the magnetic coupling with a corresponding implanted sensor coil. A simple half-bridge inverter module is developed to drive the transmitter coil through a compensation network, thereby exciting the sensor coil. The design is optimised using simulations, and experimental results are provided to validate operation for various misalignment cases. Next, a novel receiver coil system is developed to extract the IOP through magnetic coupling with the sensor coil. To simplify the design of the IOP readout, the strong magnetic coupling between the receiver and transmitter coils is decoupled using an inductor pair. Through mathematical modelling and simulations of the structure, the operation of the decoupled mutual inductor pair is determined.The experiments verify that the receiver circuit can resolve changes in the IOP sensor signal using a simple rectifier circuit, reducing the complexity of conventional readout circuits. Misalignment cases are also analysed and discussed. Finally, this thesis proposes a new stretchable conductive film based implantable capacitive sensor for IOP measurements, by investigating the characteristic of suitable materials and structures. This capacitive sensor uses a planar structure and can be easily miniaturised further. Using a conductive film with excellent biocompatibility and as a drug-release component provides for the future use of automatic drug-release attached to IOP detection devices. A mathematical model of the structural mechanics and capacitance of the proposed sensor is presented, and simulations are carried out. A prototype has been built, and the simulation results are experimentally verified, including testing and analysing the reproducibility and consistency of the sensor. Suggested future research areas are identified."]},{"key":"dc:title","label":"Title","values":["Smart Ocular Implant for Monitoring IOP in Glaucoma Patients"]}]}],"canonical_facts":{"dc:contributor.advisor":["Thrimawithana, Duleepa"],"dc:creator":["Xu, Qing"],"dc:date.accessioned":["2024-07-24T20:02:09Z"],"dc:date.available":["2024-07-24T20:02:09Z"],"dc:date.issued":["2024"],"dc:description.abstract":["Glaucoma is often called the ’thief of sight’ or the ’silent blinding eye disease’. As the world’s second most blinding eye disease and the number one irreversible eye disease, numerous studies have shown that pathological IOP is a significant risk factor. A single clinical examination of vision cannot detect an insidious increase in IOP. Therefore, long-term, uninterrupted IOP measurement is of great importance for the early diagnosis of glaucoma and individual monitoring and IOP control of glaucoma patients. Implantable IOP testing devices have been developed to perform long-term IOP measurement tasks effectively. Today’s implantable IOP devices mainly use capacitive IOP sensors as the primary operating device for remote excitation and data acquisition. Most of the research has focused on developing sensors, mainly using metal layers as the conductive plates of a capacitive sensor. Large stationary devices such as network analysers are typically used for data acquisition. The overall system lacks the original purpose of mobility and simplicity. This thesis presents an outline for an implantable IOP detection device, for which the various subsystems are designed and analysed to simplify the system for long-term IOP measurement. Firstly, a remote excitation coil system is designed and analysed. A three-dimensional transmitter coil that can be attached to the frame of a spectacle is proposed. This transmitter coil is designed to maximise the magnetic coupling with a corresponding implanted sensor coil. A simple half-bridge inverter module is developed to drive the transmitter coil through a compensation network, thereby exciting the sensor coil. The design is optimised using simulations, and experimental results are provided to validate operation for various misalignment cases. Next, a novel receiver coil system is developed to extract the IOP through magnetic coupling with the sensor coil. To simplify the design of the IOP readout, the strong magnetic coupling between the receiver and transmitter coils is decoupled using an inductor pair. Through mathematical modelling and simulations of the structure, the operation of the decoupled mutual inductor pair is determined.The experiments verify that the receiver circuit can resolve changes in the IOP sensor signal using a simple rectifier circuit, reducing the complexity of conventional readout circuits. Misalignment cases are also analysed and discussed. Finally, this thesis proposes a new stretchable conductive film based implantable capacitive sensor for IOP measurements, by investigating the characteristic of suitable materials and structures. This capacitive sensor uses a planar structure and can be easily miniaturised further. Using a conductive film with excellent biocompatibility and as a drug-release component provides for the future use of automatic drug-release attached to IOP detection devices. A mathematical model of the structural mechanics and capacitance of the proposed sensor is presented, and simulations are carried out. A prototype has been built, and the simulation results are experimentally verified, including testing and analysing the reproducibility and consistency of the sensor. Suggested future research areas are identified."],"dc:identifier.uri":["https://hdl.handle.net/2292/69319"],"dc:publisher":["ResearchSpace@Auckland"],"dc:rights":["Items in ResearchSpace are protected by copyright, with all rights reserved, unless otherwise indicated."],"dc:rights.uri":["https://researchspace.auckland.ac.nz/docs/uoa-docs/rights.htm"],"dc:title":["Smart Ocular Implant for Monitoring IOP in Glaucoma Patients"],"dc:type":["Thesis"],"thesis:degree_discipline":["Engineering"],"thesis:degree_level":["Doctoral"],"thesis:degree_name":["PhD"],"thesis:institution_name":["The University of Auckland"]},"updated_at":"2026-07-24T01:07:07Z"}