title: Implantation of a novel telemetric intraocular pressure sensor in patients with glaucoma (ARGOS study): 1-year results.
abstract: OBJECTIVE
  We investigated the safety of a telemetric IOP sensor and the accuracy of its IOP measurements in six patients with open-angle glaucoma and cataract.
  
  
  METHODS
  The study design was a prospective, single-center clinical trial. Here we present 1-year follow-up data. A ring-shaped telemetric IOP sensor was implanted in the ciliary sulcus after implantation of the intracapsular lens, during planned cataract surgery. The sensor is encapsulated in silicone rubber and consists of a miniature device with eight pressure-sensitive capacitors and a circular microcoil antenna. IOP measurements are performed with a reader unit held in front of the eye. IOP is calculated as the differences between the absolute pressure inside the eye (pressure sensor) and that outside the eye (reader unit).
  
  
  RESULTS
  The sensor was successfully implanted in all patients. Four patients developed sterile anterior chamber inflammation that resolved completely within 9 days after surgery with anti-inflammatory treatment. All patients showed mild to moderate pupillary distortion and pigment dispersion after surgery. Telemetric IOP measurement was performed in all patients at all visits, and the patients successfully performed self-tonometry at home after receiving instructions. Telemetric IOP values showed similar profiles compared to those of Goldmann applanation tonometry (GAT). Three patients showed a relevant IOP step during follow-up, and in one patient, negative values were obtained throughout the study.
  
  
  CONCLUSIONS
  Despite early postoperative anterior chamber inflammation, the IOP sensor was well tolerated by all patients. We describe the first prospective clinical study of a noncontact IOP sensor that potentially enables continuous IOP monitoring in patients with glaucoma. The sensor shape and size needs to be adapted to avoid pupillary distortion and to confirm that IOP measurements are accurately recorded in comparison to those of GAT. ( www.germanctr.de; number DRKS00003335.).
authors.affiliation: Department of Ophthalmology, RWTH Aachen University, Aachen, Germany.
authors.forename: Antonis
authors.initials: A
authors.lastname: Koutsonas
authors.affiliation: Department of Ophthalmology, RWTH Aachen University, Aachen, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Walter
authors.affiliation: Department of Ophthalmology, RWTH Aachen University, Aachen, Germany.
authors.forename: Gernot
authors.initials: G
authors.lastname: Roessler
authors.affiliation: Department of Ophthalmology, RWTH Aachen University, Aachen, Germany.
authors.forename: Niklas
authors.initials: N
authors.lastname: Plange
mesh_terms: D000368:Aged; D015374:Biosensing Techniques / Q000295:instrumentation*; D004567:Electrodes, Implanted; D004867:Equipment Design; D005260:Female; D005500:Follow-Up Studies; D005901:Glaucoma / Q000175:diagnosis / Q000503:physiopathology* / Q000601:surgery; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology*; D008297:Male; D011446:Prospective Studies; D015203:Reproducibility of Results; D013686:Telemetry / Q000295:instrumentation*; D013997:Time Factors; D014065:Tonometry, Ocular / Q000295:instrumentation*
keywords: glaucoma; intraocular pressure sensor; self tonometry