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Novel positioning sensor with real-time feedback for improved postoperative positioning: pilot study in control subjects

Brodie, Frank L. and Ramirez, David A. and Pandian, Sundar and Woo, Kelly and Balakrishna, Ashwin and De Juan, Eugene and Choo, Hyuck and Grubbs, Robert H. (2017) Novel positioning sensor with real-time feedback for improved postoperative positioning: pilot study in control subjects. Clinical Ophthalmology, 11 . pp. 939-944. ISSN 1177-5483. PMCID PMC5449164.

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Introduction: Repair of retinal detachment frequently requires use of intraocular gas. Patients are instructed to position themselves postoperatively to appose the intraocular bubble to the retinal break(s). We developed a novel wearable wireless positioning sensor, which provides real-time audiovisual feedback on the accuracy of positioning. Methods: Eight healthy volunteers wore the wireless sensor for 3 hours while instructed to maintain their head tilted toward the 2 o’clock meridian with no audiovisual feedback. Positioning accuracy was recorded. The subjects repeated the experiment for 3 hours with the audiovisual feedback enabled. Results: With no audiovisual feedback, the percentage of time greater than 10° out of position varied from 8.9% to 93.9%. With audiovisual feedback enabled, these percentages ranged from 9.4% to 65%. Three subjects showed significant improvement in their time out of position (P<0.01, Fisher’s exact test). Four subjects demonstrated a nonsignificant improvement, and one subject had a significant increase in time out of position with feedback (P<0.01). When pooled, all subjects demonstrated a statistically significant decrease in degrees out of position (P<0.001, Wilcoxon test) and a statistically significant improvement in total time out of position (P<0.001). Conclusion: The novel positioning sensor showed improved positioning compliance in half of the healthy volunteers during our short pilot study. Other subjects derived little benefit from the feedback. The causes for this observation are unclear. However, given the significant improvement as a group, this new technology could be beneficial to patients who struggle with postoperative positioning.

Item Type:Article
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URLURL TypeDescription CentralArticle
Choo, Hyuck0000-0002-8903-7939
Grubbs, Robert H.0000-0002-0057-7817
Additional Information:© 2017 The Authors. This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. Received 19 February 2017; Accepted for publication 13 April 2017; Published 19 May 2017. Support from That Man May See, Research to Prevent Blindness and Chartrand Foundation. The authors acknowledge the University of California, San Francisco Open Access Publishing Fund. Intellectual property has been filed by California Institute of Technology on behalf of the authors. Disclosure: The authors report no conflicts of interest in this work.
Funding AgencyGrant Number
That Man May See FoundationUNSPECIFIED
Research to Prevent BlindnessUNSPECIFIED
Chartrand FoundationUNSPECIFIED
University of California, San FranciscoUNSPECIFIED
Subject Keywords:retinal detachment, pneumatic retinopexy, intraocular gas, device, postoperative positioning, vitrectomy, macular hole
PubMed Central ID:PMC5449164
Record Number:CaltechAUTHORS:20170612-093023568
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:78093
Deposited By: Tony Diaz
Deposited On:12 Jun 2017 18:26
Last Modified:03 Oct 2019 18:05

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