Kim, Yong Woo Kim, Mi Jeung Park, Ki Ho Jeoung, Jin Wook Kim, Seok Hwan Jang, Cheol In Lee, Soo Hyun Kim, Jae Hun Lee, Seok Kang, Ji Yoon 2024-01-20T05:32:30Z 2024-01-20T05:32:30Z 2021-09-03 2015-12 1442-6404 https://pubs.kist.re.kr/handle/201004/124703 Background: This study aims to validate the performance and biocompatibility of an implantable inductive-type sensor for continuous monitoring of intraocular pressure (IOP) Methods: The sensor is composed of a top layer integrated with an inductor and capacitor circuit, and a bottom layer integrated with ferrite. With IOP change, the sensor's bottom layer is mechanically deflected, which changes the distance between the bottom-layer ferrite and top-layer inductor, resulting in an alteration of inductance magnitude and the resonant frequency (RF). In-vitro measurement was conducted via air pressurization in a sealing jig (n = 3). Subsequently, the sensor was implanted into the anterior chamber of a rabbit eye. In-vivo measurement was performed while the IOP was elevated by infusion of balanced salt solution (BSS, 6 mu L/min). Smaller-sized sensors later were implanted into two rabbit eyes, which were microscopically examined at 2, 4 and 8 weeks post-implantation. The eyes were then immediately enucleated for histological examination. Results: The in-vitro measurement showed a significant RF shift as pressure in the jig was increased from 0 mmHg to 60 mmHg (average initial frequency: 10.86 MHz, average shift: 403 kHz). The in-vivo measurement also showed an RF decrease, from 12.80 MHz to 12.67 MHz, as the pressure was increased from 10 mmHg to 20 mmHg. Microscopic in-vivo evaluations and histological exams, performed at intervals up to 8 weeks post-implantation, showed no evidence of significant inflammation or deformity of the ocular-tissue structures. Conclusions: The implantable inductive-type IOP sensor demonstrated wireless pressure-sensing ability and favourable biocompatibility in the rabbit eye. English WILEY VISUAL-FIELD LOSS ADVANCED GLAUCOMA INTERVENTION OPEN-ANGLE GLAUCOMA RISK-FACTOR TELEMETRY PATTERN PROGRESSION POSITION EYE Preliminary study on implantable inductive-type sensor for continuous monitoring of intraocular pressure Article 10.1111/ceo.12573 1 CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY, v.43, no.9, pp.830 - 837 CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY 43 9 830 837 scie scopus 000368342700010 2-s2.0-84949317010 Ophthalmology Ophthalmology Article VISUAL-FIELD LOSS ADVANCED GLAUCOMA INTERVENTION OPEN-ANGLE GLAUCOMA RISK-FACTOR TELEMETRY PATTERN PROGRESSION POSITION EYE continuous monitoring glaucoma intraocular pressure implantable sensor