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Use of a novel telemetric sensor to study interactions of intraocular pressure and ganglion-cell function in glaucoma
  1. Khaldoon O Al-Nosairy1,
  2. Jacqueline J O N van den Bosch1,2,
  3. Vincenzo Pennisi1,
  4. Kaweh Mansouri3,4,
  5. Hagen Thieme1,
  6. Lars Choritz1,
  7. Michael B Hoffmann1,5
  1. 1 Department of Ophthalmology, Otto von Guericke University, Magdeburg, Germany
  2. 2 Department of Research and Development, Implandata Ophthalmic Products GmbH, Hannover, Germany
  3. 3 Glaucoma Research Centre, Montchoisi Clinic, Swiss Visio, Lausanne, Switzerland
  4. 4 Department of Ophthalmology, University of Colorado School of Medicine, Denver, Colorado, USA
  5. 5 Center for Behavioral Brain Sciences, Otto von Guericke University, Magdeburg, Germany
  1. Correspondence to Michael B Hoffmann, Visual Processing Laboratory, University Eye Clinic, Leipziger Str. 44, 39120 Magdeburg, Germany; michael.hoffmann{at}


Aims (1) To test the feasibility of simultaneous steady-state pattern electroretinogram (ssPERG) and intraocular pressure (IOP) measurements with an implanted IOP sensor. (2) To explore the scope of this approach for detecting PERG changes during IOP manipulation in a model of lateral decubitus positioning (LDP; lateral position).

Methods 15 healthy controls and 15 treated glaucoma patients participated in the study. 8 patients had an IOP sensor (Eyemate-IO, Implandata Ophthalmic Products GmbH) in the right eye (GLAIMP) and 7 had no sensor and with glaucoma in the left eye. (1) We compared PERGs with and without simultaneous IOP read-out in GLAIMP. (2) All participants were positioned in the following order: sitting1 (S1), right LDP (LDR), sitting2 (S2), left LDP (LDL) and sitting3 (S3). For each position, PERG amplitudes and IOP were determined with rebound tonometry (Icare TA01i) in all participants without the IOP sensor.

Results Electromagnetic intrusions of IOP sensor read-out onto ssPERG recordings had, due to different frequency ranges, no relevant effect on PERG amplitudes. IOP and PERG measures were affected by LDP, for example, IOP was increased during LDR versus S1 in the lower eyes of GLAIMP and controls (5.1±0.6 mmHg, P0.025=0.00004 and 1.6±0.6 mmHg, P0.025=0.02, respectively) and PERG amplitude was reversibly decreased (−25±10%, P0.025=0.02 and −17±5%, P0.025, respectively).

Conclusions During LDP, both IOP and PERG changed predominantly in the lower eye. IOP changes induced by LDP may be a model for studying the interaction of IOP and ganglion-cell function.

  • Glaucoma
  • Intraocular pressure
  • Physiology
  • Telemedicine
  • Electrophysiology

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  • Contributors MBH and LC obtained funding and supervised the study. MBH, LC and KOA contributed to study concept and design. KOA, JJONvdB and VP collected the data. KOA analysed the data. MBH and KOA drafted the manuscript. All authors critically discussed the results, commented on and revised the manuscript.

  • Funding This work was supported by European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement (No. 675033) to MBH and LC and by funding of the German research foundation to MBH (DFG; HO2002/20-1).

  • Competing interests JJONvdB is currently employed at Implandata as PhD student within EGRET+ supported by EU-funded postgraduate training programme under the Marie Sklodowska-Curie grant agreement (No. 675033). KM is currently working as consultant for Implandata.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Data sharing statement Data are available upon reasonable request.

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