TY - JOUR
T1 - Intraocular Pressure Measurement with Pneumatonometry and a Tonometer Tip Cover
AU - Ferguson, Tanner J.
AU - Knier, Catherine G.
AU - Chowdhury, Uttio Roy
AU - Monson, Kjerseten J.
AU - Greenwood, Michael
AU - Swan, Russell J.
AU - Gorham, Richard
AU - Berdahl, John P.
AU - Fautsch, Michael P.
N1 - Funding Information:
The study and the rapid service fee for this publication were funded by Equinox Ophthalmic, Inc. There were no other funding sources.
Funding Information:
We thank the operators who performed the tasks described in this study to generate the data and study results. The study and the rapid service fee for this publication were funded by Equinox Ophthalmic, Inc. There were no other funding sources. All named authors meet the International Committee of Medical Journal Editors (ICMJE) criteria for authorship for this article, take responsibility for the integrity of the work as a whole, and have given their approval for this version to be published. Drs. Tanner J. Ferguson, Russell J. Swan and Michael Greenwood are consultants for Equinox Ophthalmic, Inc. Dr. John P. Berdahl is the founder and CEO of Equinox Ophthalmic, Inc. Mr. Richard Gorham, Ms. Catherine G. Knier, Ms. Kjerseten J. Monson, Dr Uttio Roy Chowdhury and Dr Michael P. Fautsch have no relevant financial disclosures. All procedures conducted were in accordance with the Aspire IRB and the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. Human eyes were obtained from the Minnesota Lion’s Eye Bank. For eyes obtained through the eye bank, Minnesota Lion’s Eye Bank received written consent from family to use eyes for research purposes. The data set collected and analyzed for this present study is available from the corresponding author per reasonable request.
Publisher Copyright:
© 2020, The Author(s).
PY - 2020/3/1
Y1 - 2020/3/1
N2 - Purpose: To investigate the precision and accuracy of IOP measurements using a pneumatonometer and a tonometer tip cover (Tono-Pen® tip cover) acting as a membrane between a cadaver eye model and pneumatonometer probe. Methods: A total of 480 paired IOP measurements, with and without a Tono-Pen cover, were collected across 4 pressure levels of 7, 10, 20 and 30 mmHg. IOP measurements were obtained by three different pneumatonometer units paired with three different masked operators (three configurations). Four eyes were sampled for each eye pressure level. The sequence of eye pressure, configuration, and measurements with vs. without the Tono-Pen cover was randomized. Results: With the Tono-Pen cover in place, there was a negative bias with a mean IOP difference of − 1.18 mmHg for all 480 paired samples compared with the measurements absent the cover. Compared with the test pressure settings (i.e., 7, 10, 20, 30 mmHg), the overall mean bias was + 0.35 mmHg with the Tono-Pen cover present. With the Tono-Pen cover present, the overall repeatability %CV (percent coefficient of variation) was 3.4% and the reproducibility %CV was 3.8% compared with a repeatability %CV of 3.2% and reproducibility %CV of 5.7% without the Tono-Pen cover. Conclusion: Measurement of IOP via pneumatonometry with a Tono-Pen cover in place, also known as the excursion test method, yields precise, accurate and reproducible results. This developed method of pressure measurement is an acceptable and reliable form of IOP measurement.
AB - Purpose: To investigate the precision and accuracy of IOP measurements using a pneumatonometer and a tonometer tip cover (Tono-Pen® tip cover) acting as a membrane between a cadaver eye model and pneumatonometer probe. Methods: A total of 480 paired IOP measurements, with and without a Tono-Pen cover, were collected across 4 pressure levels of 7, 10, 20 and 30 mmHg. IOP measurements were obtained by three different pneumatonometer units paired with three different masked operators (three configurations). Four eyes were sampled for each eye pressure level. The sequence of eye pressure, configuration, and measurements with vs. without the Tono-Pen cover was randomized. Results: With the Tono-Pen cover in place, there was a negative bias with a mean IOP difference of − 1.18 mmHg for all 480 paired samples compared with the measurements absent the cover. Compared with the test pressure settings (i.e., 7, 10, 20, 30 mmHg), the overall mean bias was + 0.35 mmHg with the Tono-Pen cover present. With the Tono-Pen cover present, the overall repeatability %CV (percent coefficient of variation) was 3.4% and the reproducibility %CV was 3.8% compared with a repeatability %CV of 3.2% and reproducibility %CV of 5.7% without the Tono-Pen cover. Conclusion: Measurement of IOP via pneumatonometry with a Tono-Pen cover in place, also known as the excursion test method, yields precise, accurate and reproducible results. This developed method of pressure measurement is an acceptable and reliable form of IOP measurement.
KW - Diagnostics
KW - Intraocular pressure
KW - Open-angle glaucoma
KW - Ophthalmic techniques
KW - Tonometry
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U2 - 10.1007/s40123-020-00235-z
DO - 10.1007/s40123-020-00235-z
M3 - Article
AN - SCOPUS:85080999050
SN - 2193-8245
VL - 9
SP - 127
EP - 137
JO - Ophthalmology and Therapy
JF - Ophthalmology and Therapy
IS - 1
ER -