Effect of Contact Lenses on Measurements by Non-Contact tonometry, Dynamic Contour Tonometry, and Tono-Pen

Effect of Contact Lenses on Measurements by Non-Contact tonometry, Dynamic Contour Tonometry, and Tono-Pen | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Effect of Contact Lenses on Measurements by Non-Contact tonometry, Dynamic Contour Tonometry, and Tono-Pen Cengiz Akarsu, Sertaç Öztürk, Esra Kızıldağ Özbay This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7972795/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Purpose: To investigate the effect of soft contact lens wear on intraocular pressure (IOP) measurements obtained using non-contact tonometry (NCT), Pascal dynamic contour tonometry (Pascal-DCT), and the Tono-Pen. Methods: Twenty-nine eyes of 29 healthy volunteers were included in the study. Following a routine ophthalmologic examination, central corneal thickness was measured using an ultrasonic pachymeter. Intraocular pressure (IOP) was measured before and after soft contact lens application using NCT, Pascal-DCT, and the Tono-Pen in random order. The differences between pre- and post–soft contact lens measurements were statistically analyzed using the paired t-test. Results: The mean age of the 29 healthy volunteers who participated in the study was 52.6 ± 15.4 years (range, 21–73 years). Corneal thickness measurements in all participants ranged from 506 µm to 610 µm (mean, 557.4 ± 31.6 µm). Before soft contact lens application, mean intraocular pressure (IOP) values obtained with Goldmann applanation tonometry (GAT), NCT, Pascal-DCT, and Tono-Pen were 16.1 ± 2.8 mmHg, 16.7 ± 3.8 mmHg, 17.7 ± 2.6 mmHg, and 17.2 ± 3.6 mmHg, respectively (P = 0.6). After soft contact lens application, IOP values measured with NCT, Pascal-DCT, and Tono-Pen were 14.4 ± 3.8 mmHg, 16.5 ± 2.8 mmHg, and 16.9 ± 3.8 mmHg, respectively. IOP values measured with NCT and Pascal-DCT were found to be significantly lower after lens application (P < 0.01 for both). Although IOP values measured with the Tono-Pen were also lower after lens application, the difference was not statistically significant (P = 0.33). Conclusion: In this study, we demonstrated that IOP can be reliably measured using the NCT, Tono-Pen, and Pascal-DCT in a limited number of participants. However, it should be kept in mind that lower IOP values are obtained when measurements are performed with the NCT and Pascal-DCT without removing the soft contact lens. Although the Tono-Pen also yields slightly lower readings in eyes wearing a soft contact lens, it should be noted that the Tono-Pen appears to be the most accurate device for measuring IOP without lens removal. Goldman applanation tonometry non-contact tonometry Pascal dynamic contour tonometry Tono-Pen Intraocular pressure soft contact lens INTRODUCTION Measurement of intraocular pressure (IOP) is a fundamental component of routine ophthalmic examinations. Close monitoring of IOP is particularly important in patients with glaucoma, suspected glaucoma, or individuals over the age of 40 years. Goldmann applanation tonometry (GAT) remains the most commonly used and widely accepted gold standard method for assessing IOP [ 1 ]. However, GAT readings can be influenced by several factors, including corneal thickness, curvature, biomechanical properties, and astigmatism [ 2 ]. Pascal dynamic contour tonometry (Pascal-DCT) is a contact method that simultaneously records IOP and ocular pulse amplitude. Recent studies have demonstrated that Pascal-DCT is less affected by central corneal thickness and corneal curvature [ 3 ]. The Tono-Pen, a portable electronic tonometer based on the MacKay-Marg principle, allows for convenient measurement in both clinical and bedside settings [ 4 ]. Non-contact tonometry (NCT), which determines IOP by directing a puff of air onto the corneal surface, is commonly used in busy outpatient clinics and screening programs due to its ease of use and non-invasive nature. The use of soft contact lenses has steadily increased in recent years, not only for cosmetic and refractive correction but also for therapeutic purposes. Soft contact lenses are frequently used to relieve pain in corneal disorders, promote epithelial healing, protect the cornea from mechanical stress, and maintain corneal hydration [ 5 ]. Additionally, they can improve visual quality in eyes with irregular corneal surfaces. Tonometry should not be overlooked in patients wearing contact lenses. Frequent removal of soft lenses can cause temporary IOP fluctuations and may adversely affect epithelial healing [ 6 ], while also increasing examination time in clinical practice. Although rigid gas-permeable contact lenses must be removed before IOP measurement, IOP can be measured through soft contact lenses using NCT, Pascal-DCT, or the Tono-Pen [ 7 – 11 ]. Therefore, the aim of this study was to determine which tonometry method provides the most accurate IOP measurements in eyes wearing soft contact lenses. MATERIALS AND METHODS This prospective study included 29 eyes of 29 healthy volunteers who presented to the outpatient clinic of the Department of Ophthalmology, Ufuk University, and had no known ocular pathology. If both eyes of a volunteer met the inclusion criteria, only one eye was randomly selected. Each participant underwent best-corrected visual acuity assessment, slit-lamp biomicroscopic examination, and dilated fundus evaluation. Inclusion criteria were: age over 18 years, absence of systemic disease, no ocular pathology, and no evidence of corneal degeneration or dystrophy. Exclusion criteria were: amblyopia, astigmatism greater than 2.0 diopters, glaucoma, corneal disease, ocular inflammation, history of ocular surgery or trauma, and prior contact lens wear. The study protocol was explained to all participants, and written informed consent was obtained. The study adhered to the tenets of the Declaration of Helsinki. Topical anesthesia (Alcaine) was administered to all participants, and central corneal thickness was measured using ultrasonic pachymetry. Intraocular pressure was then measured with the Goldmann applanation tonometer mounted on a slit lamp, a non-contact tonometer (Topcon CT-80A), the Tono-Pen XL (Medtronic), and Pascal dynamic contour tonometer (SMT Swiss Microtechnology AG, Port, Switzerland). All measurements were performed in random order by the same examiner, initially without a soft contact lens. Subsequently, a soft contact lens (Night & Day; CIBA Vision) was applied 30 minutes after the first set of measurements, and IOP was remeasured in random order using all devices except the GAT. Three readings were obtained with each device, and the mean value was used for statistical analysis. For Pascal-DCT, measurements were taken for at least 7 seconds, and only those with a quality score (Q value) below 3 were included. For the Tono-Pen, only readings with a standard deviation ≤ 5% were accepted. Statistical comparisons between pre– and post–soft contact lens measurements were performed using the paired t -test. A P value < 0.05 was considered statistically significant. RESULTS The study included 29 participants (13 males, 16 females) with a mean age of 52.2 ± 15.4 years (range, 21–73 years). Central corneal thickness ranged from 506 µm to 610 µm (mean, 557.4 ± 31.6 µm). Before soft contact lens application, mean intraocular pressure (IOP) values measured with GAT, NCT, Pascal-DCT, and Tono-Pen were 16.1 ± 2.8 mmHg, 16.7 ± 3.8 mmHg, 17.7 ± 2.6 mmHg, and 17.2 ± 3.6 mmHg, respectively. After soft contact lens application, IOP values measured with NCT, Pascal-DCT, and Tono-Pen were 14.4 ± 3.8 mmHg, 16.5 ± 2.8 mmHg, and 16.9 ± 3.8 mmHg, respectively. Comparison of IOP values before and after soft contact lens application revealed that measurements obtained using NCT and Pascal-DCT were significantly lower after lens application (P < 0.01 for both). Although IOP values measured with the Tono-Pen were also lower after lens application, the difference was not statistically significant (P = 0.33). Before contact lens application, IOP values obtained using various methods showed the lowest readings with GAT and the highest with Pascal-DCT. However, analysis of variance (ANOVA) indicated no statistically significant difference among pre–contact lens IOP values (P = 0.6). Pre– and post–contact lens IOP values obtained with NCT, Pascal-DCT, and Tono-Pen, along with the corresponding statistical comparisons, are summarized in Table 1 . Table 1 Intraocular pressure (IOP) values ​​determined before and after contact lens application Measurement Method Pre-Contact Lens IOP (mm Hg)* Post-Contact Lens IOP (mm Hg) P GAT 16.1 ± 2.8 mm Hg N/A NCT 16.7 ± 3.8 14.4 ± 3.8 < 0.01 Pascal-DCT 17.7 ± 2.6 16.5 ± 2.8 < 0.01 Tonopen 17.2 ± 3.6 16.9 ± 3.8 0.33 * Pre–contact lens IOP values were similar across measurement methods (one-way ANOVA, P = 0.6). Values are presented as mean ± standard deviation (SD). DISCUSSION In the presence of a pathological cornea, various challenges arise when measuring IOP using GAT. Accurate IOP measurement is particularly important in cases with glaucoma-associated corneal scarring, Axenfeld–Rieger syndrome, Peters anomaly, iridocorneal endothelial syndrome, corneal surface disorders, or in patients receiving long-term steroid therapy. In such conditions, silicone hydrogel contact lenses have recently been used more frequently for therapeutic purposes due to their high oxygen permeability [ 12 , 13 ]. Consequently, situations that require careful IOP monitoring while using contact lenses are commonly encountered. In our study, IOP was measured using various methods without removing the soft contact lens in eyes without pathological findings, and the accuracy of these measurements was evaluated. IOP measurements obtained without a soft contact lens were found to be similar across all tonometers. However, after the application of a soft contact lens, IOP values measured using NCT and Pascal-DCT were significantly lower. Although lower IOP values were also observed with the Tono-Pen after contact lens application, this difference was not statistically significant. GAT was not used after soft contact lens application in our study. Performing GAT measurements requires sodium fluorescein application or modification of the procedure. Fluorescein permanently stains the contact lens, altering its physical structure and central thickness. It has been reported that IOP values measured without fluorescein are approximately 2 mmHg lower, regardless of whether a soft contact lens is present [ 14 ]. For these reasons, GAT measurements were not performed after soft contact lens application in this study. IOP measurements obtained while wearing a soft contact lens are known to be influenced by the lens’s water content, central thickness, material, and refractive power [ 15 – 17 ]. Moreover, long-term use of soft contact lenses can also affect IOP measurement accuracy [ 11 ]. In our study, − 0.50 D lenses were used, and all were freshly opened. However, the effects of soft contact lenses with different powers and materials on IOP measurements should be investigated in larger study populations. Fırat et al. [ 18 ] investigated the effect of soft contact lenses on IOP measurements using GAT, NCT, and DCT. They reported that before contact lens application, the lowest IOP was measured with GAT, and that NCT and DCT measurements were statistically higher. Similarly, after contact lens application, both DCT and NCT showed lower IOP values, although only the reduction in NCT measurements was statistically insignificant. Patel et al. [ 16 ] concluded that NCT can provide sufficiently accurate measurements through a soft contact lens, provided that the lens central thickness does not exceed 0.30 mm and the power is ≤ + 3.00 D. In our study, we used − 0.50 D Night & Day soft contact lenses with a central thickness of 0.08 mm, which we believe did not negatively affect the tonometry readings. In our study, although the lowest IOP before contact lens application was recorded with GAT, no statistically significant differences were found between the measurement methods. After contact lens application, IOP values decreased, consistent with the findings of Fırat et al [ 18 ]. However, only theTono-Pen measurements remained statistically similar before and after contact lens application. Mark et al. [ 19 ] evaluated the accuracy of IOP measurements using a pneumotonometer and Tono-Pen through bandage contact lenses. They adjusted the IOP of nine cadaver eyes manometrically in 10 mmHg increments, ranging from 10 to 50 mmHg, and demonstrated that readings from both devices correlated with the manometric standard. Their study also showed that pneumotonometer readings were more accurate than those from the Tono-Pen. The study by Mark et al. [ 19 ] differs from ours in that it was conducted on cadaver eyes using a manometer. In conclusion, in this limited series of healthy eyes, IOP measurements obtained with NCT, Pascal-DCT, and Tono-Pen were all lower during soft contact lens wear. However, the pressure readings obtained with the Tono-Pen were statistically similar to those obtained without contact lenses, suggesting that Tono-Pen may be the most reliable method for IOP measurement without removing soft contact lenses. Declarations Ethical approval: All procedures involving human participants were conducted in accordance with the ethical standards of the Ufuk University Research Ethics Committee and the 1964 Declaration of Helsinki. Clinical trial number not applicable. Informed consent Informed consent was obtained from all individual participants included in the study. Conflict of interest: The authors have no commercial or proprietary interest in any of the equipment and medication mentioned in this study. Funding: No funds, grants, or other support was received. Author Contribution All authors (Cengiz Akarsu, Sertaç Öztürk, and Esra Kızıldağ Özbay) contributed to the study design. Material preparation, data collection, and analysis were performed by Cengiz Akarsu, Sertaç Öztürk, and Esra Kızıldağ Özbay. The manuscript was written by Cengiz Akarsu and Esra Kızıldağ Özbay. All authors reviewed and approved the final version of the manuscript. References Dielemans I, Vingerling JR, Hofman A, Grobbee DE, de Jong PT. Reliability of intraocular pressure measurement with the Goldmann applanation tonometer in epidemiological studies. Graefes Arch Clin Exp Ophthalmol. 1994;232:141–144. Whitacre MM, Stein R. Sources of error with use of Goldmann-type tonometers. Surv Ophthalmol. 1993;38:1–30. Kaufmann C, Bachmann LM, Thiel MA. Intraocular pressure measurements using dynamic contour tonometry after laser in situ keratomileusis. Invest Ophthalmol Vis Sci. 2003;44:3790–3794. Frenkel RP, Hong J, Shin DH. Comparison of the Tono-Pen to the Goldmann applanation tonometer. Arch Ophthalmol. 1988;106:750–753. Blackmore SJ. The use of contact lenses in the treatment of persistent epithelial defects. Cont Lens Anterior Eye. 2010;33:239–244. Khan JA, Graham CE. Effect of contact lens removal or displacement on intraocular pressure. Arch Ophthalmol. 1991;109:825–828. Rubenstein JB, Deutsch TA. Pneumatonometry through bandage contact lenses. Arch Ophthalmol. 1985;103:1660–1661. McMonnies CW. Noncontact tonometry through soft contact lenses. Am J Optom Physiol Opt. 1986;63:948–951. Insler MS, Robbins RG. Intraocular pressure by noncontact tonometry with and without soft contact lenses. Arch Ophthalmol. 1987;105:1358–1359. Panek WC, Boothe WA, Lee DA, Zemplenyi E, Pettit TH. Intraocular pressure measurement with the Tono-Pen through soft contact lenses. Am J Ophthalmol. 1990;109:62–65. Scibilia GD, Ehlers WH, Donshik PC. The effects of therapeutic contact lenses on intraocular pressure measurement. CLAO J. 1996;22:262–265. Lim L, Tan DT, Chan WK. Therapeutic use of Bausch & Lomb PureVision contact lenses. CLAO J. 2001;27(4):179–185. Montero J, Sparholt J, Mely R. Retrospective case series of therapeutic applications of a lotrafilcon A silicone hydrogel soft contact lens. Eye Contact Lens . 2003;29(Suppl 1):S54–S56; discussion S57–S59, S192–S194. Lim L, Ng TP, Tan DT. Accurate intraocular pressure measurement in contact lens wearers with normal pressures. CLAO J. 1997;23(2):130–133. McMonnies CW. Noncontact tonometry through soft contact lenses. Am J Optom Physiol Opt. 1986;63(12):948–951. Patel S, Illahi W. Non-contact tonometry over soft contact lenses: effect of contact lens power on the measurement of intraocular pressure. Cont Lens Anterior Eye. 2004;27(1):33–37. Insler MS, Robbins RG. Intraocular pressure by noncontact tonometry with and without soft contact lenses. Arch Ophthalmol. 1987;105(10):1358–1359. Fırat PG, Cankaya C, Doganay S, Cavdar M, Duman S, Ozsoy E, Koc B. The influence of soft contact lenses on intraocular pressure measurement. Eye (Lond) . 2012;26(2):278–282. Mark LK, Asbell PA, Torres MA, Failla SJ. Accuracy of intraocular pressure measurements with two different tonometers through bandage contact lenses. Cornea. 1992;11(4):277–281. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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pressure (IOP) is a fundamental component of routine ophthalmic examinations. Close monitoring of IOP is particularly important in patients with glaucoma, suspected glaucoma, or individuals over the age of 40 years. Goldmann applanation tonometry (GAT) remains the most commonly used and widely accepted gold standard method for assessing IOP [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. However, GAT readings can be influenced by several factors, including corneal thickness, curvature, biomechanical properties, and astigmatism [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e].\u003c/p\u003e\u003cp\u003ePascal dynamic contour tonometry (Pascal-DCT) is a contact method that simultaneously records IOP and ocular pulse amplitude. Recent studies have demonstrated that Pascal-DCT is less affected by central corneal thickness and corneal curvature [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. The Tono-Pen, a portable electronic tonometer based on the MacKay-Marg principle, allows for convenient measurement in both clinical and bedside settings [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Non-contact tonometry (NCT), which determines IOP by directing a puff of air onto the corneal surface, is commonly used in busy outpatient clinics and screening programs due to its ease of use and non-invasive nature.\u003c/p\u003e\u003cp\u003eThe use of soft contact lenses has steadily increased in recent years, not only for cosmetic and refractive correction but also for therapeutic purposes. Soft contact lenses are frequently used to relieve pain in corneal disorders, promote epithelial healing, protect the cornea from mechanical stress, and maintain corneal hydration [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Additionally, they can improve visual quality in eyes with irregular corneal surfaces.\u003c/p\u003e\u003cp\u003eTonometry should not be overlooked in patients wearing contact lenses. Frequent removal of soft lenses can cause temporary IOP fluctuations and may adversely affect epithelial healing [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e], while also increasing examination time in clinical practice. Although rigid gas-permeable contact lenses must be removed before IOP measurement, IOP can be measured through soft contact lenses using NCT, Pascal-DCT, or the Tono-Pen [\u003cspan additionalcitationids=\"CR8 CR9 CR10\" citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eTherefore, the aim of this study was to determine which tonometry method provides the most accurate IOP measurements in eyes wearing soft contact lenses.\u003c/p\u003e"},{"header":"MATERIALS AND METHODS","content":"\u003cp\u003eThis prospective study included 29 eyes of 29 healthy volunteers who presented to the outpatient clinic of the Department of Ophthalmology, Ufuk University, and had no known ocular pathology. If both eyes of a volunteer met the inclusion criteria, only one eye was randomly selected. Each participant underwent best-corrected visual acuity assessment, slit-lamp biomicroscopic examination, and dilated fundus evaluation.\u003c/p\u003e\u003cp\u003e\u003cb\u003eInclusion criteria\u003c/b\u003e were: age over 18 years, absence of systemic disease, no ocular pathology, and no evidence of corneal degeneration or dystrophy.\u003c/p\u003e\u003cp\u003e\u003cb\u003eExclusion criteria\u003c/b\u003e were: amblyopia, astigmatism greater than 2.0 diopters, glaucoma, corneal disease, ocular inflammation, history of ocular surgery or trauma, and prior contact lens wear.\u003c/p\u003e\u003cp\u003e The study protocol was explained to all participants, and written informed consent was obtained. The study adhered to the tenets of the Declaration of Helsinki.\u003c/p\u003e\u003cp\u003eTopical anesthesia (Alcaine) was administered to all participants, and central corneal thickness was measured using ultrasonic pachymetry. Intraocular pressure was then measured with the Goldmann applanation tonometer mounted on a slit lamp, a non-contact tonometer (Topcon CT-80A), the Tono-Pen XL (Medtronic), and Pascal dynamic contour tonometer (SMT Swiss Microtechnology AG, Port, Switzerland). All measurements were performed in random order by the same examiner, initially without a soft contact lens.\u003c/p\u003e\u003cp\u003eSubsequently, a soft contact lens (Night \u0026amp; Day; CIBA Vision) was applied 30 minutes after the first set of measurements, and IOP was remeasured in random order using all devices except the GAT. Three readings were obtained with each device, and the mean value was used for statistical analysis. For Pascal-DCT, measurements were taken for at least 7 seconds, and only those with a quality score (Q value) below 3 were included. For the Tono-Pen, only readings with a standard deviation\u0026thinsp;\u0026le;\u0026thinsp;5% were accepted.\u003c/p\u003e\u003cp\u003eStatistical comparisons between pre\u0026ndash; and post\u0026ndash;soft contact lens measurements were performed using the paired \u003cem\u003et\u003c/em\u003e-test. A \u003cem\u003eP\u003c/em\u003e value\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistically significant.\u003c/p\u003e"},{"header":"RESULTS","content":"\u003cp\u003eThe study included 29 participants (13 males, 16 females) with a mean age of 52.2\u0026thinsp;\u0026plusmn;\u0026thinsp;15.4 years (range, 21\u0026ndash;73 years). Central corneal thickness ranged from 506 \u0026micro;m to 610 \u0026micro;m (mean, 557.4\u0026thinsp;\u0026plusmn;\u0026thinsp;31.6 \u0026micro;m).\u003c/p\u003e\u003cp\u003eBefore soft contact lens application, mean intraocular pressure (IOP) values measured with GAT, NCT, Pascal-DCT, and Tono-Pen were 16.1\u0026thinsp;\u0026plusmn;\u0026thinsp;2.8 mmHg, 16.7\u0026thinsp;\u0026plusmn;\u0026thinsp;3.8 mmHg, 17.7\u0026thinsp;\u0026plusmn;\u0026thinsp;2.6 mmHg, and 17.2\u0026thinsp;\u0026plusmn;\u0026thinsp;3.6 mmHg, respectively. After soft contact lens application, IOP values measured with NCT, Pascal-DCT, and Tono-Pen were 14.4\u0026thinsp;\u0026plusmn;\u0026thinsp;3.8 mmHg, 16.5\u0026thinsp;\u0026plusmn;\u0026thinsp;2.8 mmHg, and 16.9\u0026thinsp;\u0026plusmn;\u0026thinsp;3.8 mmHg, respectively.\u003c/p\u003e\u003cp\u003eComparison of IOP values before and after soft contact lens application revealed that measurements obtained using NCT and Pascal-DCT were significantly lower after lens application (P\u0026thinsp;\u0026lt;\u0026thinsp;0.01 for both). Although IOP values measured with the Tono-Pen were also lower after lens application, the difference was not statistically significant (P\u0026thinsp;=\u0026thinsp;0.33).\u003c/p\u003e\u003cp\u003eBefore contact lens application, IOP values obtained using various methods showed the lowest readings with GAT and the highest with Pascal-DCT. However, analysis of variance (ANOVA) indicated no statistically significant difference among pre\u0026ndash;contact lens IOP values (P\u0026thinsp;=\u0026thinsp;0.6).\u003c/p\u003e\u003cp\u003ePre\u0026ndash; and post\u0026ndash;contact lens IOP values obtained with NCT, Pascal-DCT, and Tono-Pen, along with the corresponding statistical comparisons, are summarized in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eIntraocular pressure (IOP) values ​​determined before and after contact lens application\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"4\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMeasurement Method\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePre-Contact Lens IOP\u003c/p\u003e\u003cp\u003e(mm Hg)*\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003ePost-Contact Lens IOP (mm Hg)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eP\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eGAT\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e16.1\u0026thinsp;\u0026plusmn;\u0026thinsp;2.8 mm Hg\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eN/A\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eNCT\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e16.7\u0026thinsp;\u0026plusmn;\u0026thinsp;3.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e14.4\u0026thinsp;\u0026plusmn;\u0026thinsp;3.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.01\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePascal-DCT\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e17.7\u0026thinsp;\u0026plusmn;\u0026thinsp;2.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e16.5\u0026thinsp;\u0026plusmn;\u0026thinsp;2.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.01\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eTonopen\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e17.2\u0026thinsp;\u0026plusmn;\u0026thinsp;3.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e16.9\u0026thinsp;\u0026plusmn;\u0026thinsp;3.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.33\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e* Pre\u0026ndash;contact lens IOP values were similar across measurement methods (one-way ANOVA, P\u0026thinsp;=\u0026thinsp;0.6).\u003c/p\u003e\u003cp\u003eValues are presented as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation (SD).\u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eIn the presence of a pathological cornea, various challenges arise when measuring IOP using GAT. Accurate IOP measurement is particularly important in cases with glaucoma-associated corneal scarring, Axenfeld\u0026ndash;Rieger syndrome, Peters anomaly, iridocorneal endothelial syndrome, corneal surface disorders, or in patients receiving long-term steroid therapy. In such conditions, silicone hydrogel contact lenses have recently been used more frequently for therapeutic purposes due to their high oxygen permeability [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Consequently, situations that require careful IOP monitoring while using contact lenses are commonly encountered.\u003c/p\u003e\u003cp\u003eIn our study, IOP was measured using various methods without removing the soft contact lens in eyes without pathological findings, and the accuracy of these measurements was evaluated. IOP measurements obtained without a soft contact lens were found to be similar across all tonometers. However, after the application of a soft contact lens, IOP values measured using NCT and Pascal-DCT were significantly lower. Although lower IOP values were also observed with the Tono-Pen after contact lens application, this difference was not statistically significant.\u003c/p\u003e\u003cp\u003eGAT was not used after soft contact lens application in our study. Performing GAT measurements requires sodium fluorescein application or modification of the procedure. Fluorescein permanently stains the contact lens, altering its physical structure and central thickness. It has been reported that IOP values measured without fluorescein are approximately 2 mmHg lower, regardless of whether a soft contact lens is present [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. For these reasons, GAT measurements were not performed after soft contact lens application in this study.\u003c/p\u003e\u003cp\u003eIOP measurements obtained while wearing a soft contact lens are known to be influenced by the lens\u0026rsquo;s water content, central thickness, material, and refractive power [\u003cspan additionalcitationids=\"CR16\" citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. Moreover, long-term use of soft contact lenses can also affect IOP measurement accuracy [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. In our study, \u0026minus;\u0026thinsp;0.50 D lenses were used, and all were freshly opened. However, the effects of soft contact lenses with different powers and materials on IOP measurements should be investigated in larger study populations.\u003c/p\u003e\u003cp\u003eFırat et al. [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e] investigated the effect of soft contact lenses on IOP measurements using GAT, NCT, and DCT. They reported that before contact lens application, the lowest IOP was measured with GAT, and that NCT and DCT measurements were statistically higher. Similarly, after contact lens application, both DCT and NCT showed lower IOP values, although only the reduction in NCT measurements was statistically insignificant. Patel et al. [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e] concluded that NCT can provide sufficiently accurate measurements through a soft contact lens, provided that the lens central thickness does not exceed 0.30 mm and the power is \u0026le;\u0026thinsp;+\u0026thinsp;3.00 D. In our study, we used \u0026minus;\u0026thinsp;0.50 D Night \u0026amp; Day soft contact lenses with a central thickness of 0.08 mm, which we believe did not negatively affect the tonometry readings.\u003c/p\u003e\u003cp\u003eIn our study, although the lowest IOP before contact lens application was recorded with GAT, no statistically significant differences were found between the measurement methods. After contact lens application, IOP values decreased, consistent with the findings of Fırat et al [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. However, only theTono-Pen measurements remained statistically similar before and after contact lens application.\u003c/p\u003e\u003cp\u003eMark et al. [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e] evaluated the accuracy of IOP measurements using a pneumotonometer and Tono-Pen through bandage contact lenses. They adjusted the IOP of nine cadaver eyes manometrically in 10 mmHg increments, ranging from 10 to 50 mmHg, and demonstrated that readings from both devices correlated with the manometric standard. Their study also showed that pneumotonometer readings were more accurate than those from the Tono-Pen. The study by Mark et al. [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e] differs from ours in that it was conducted on cadaver eyes using a manometer.\u003c/p\u003e\u003cp\u003eIn conclusion, in this limited series of healthy eyes, IOP measurements obtained with NCT, Pascal-DCT, and Tono-Pen were all lower during soft contact lens wear. However, the pressure readings obtained with the Tono-Pen were statistically similar to those obtained without contact lenses, suggesting that Tono-Pen may be the most reliable method for IOP measurement without removing soft contact lenses.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eEthical approval:\u003c/h2\u003e\n\u003cp\u003eAll procedures involving human participants were conducted in accordance with the ethical standards of the Ufuk University Research Ethics Committee and the 1964 Declaration of Helsinki.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eClinical trial number\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003enot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eInformed consent\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eInformed consent was obtained from all individual participants included in the study.\u003c/p\u003e\n\u003ch2\u003eConflict of interest:\u003c/h2\u003e\n\u003cp\u003eThe authors have no commercial or proprietary interest in any of the equipment and medication mentioned in this study.\u003c/p\u003e\n\u003ch2\u003eFunding:\u003c/h2\u003e\n\u003cp\u003eNo funds, grants, or other support was received.\u003c/p\u003e\n\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\n\u003cp\u003eAll authors (Cengiz Akarsu, Serta\u0026ccedil; \u0026Ouml;zt\u0026uuml;rk, and Esra Kızıldağ \u0026Ouml;zbay) contributed to the study design. Material preparation, data collection, and analysis were performed by Cengiz Akarsu, Serta\u0026ccedil; \u0026Ouml;zt\u0026uuml;rk, and Esra Kızıldağ \u0026Ouml;zbay. The manuscript was written by Cengiz Akarsu and Esra Kızıldağ \u0026Ouml;zbay. All authors reviewed and approved the final version of the manuscript.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eDielemans I, Vingerling JR, Hofman A, Grobbee DE, de Jong PT. Reliability of intraocular pressure measurement with the Goldmann applanation tonometer in epidemiological studies. \u003cem\u003eGraefes Arch Clin Exp Ophthalmol.\u003c/em\u003e 1994;232:141\u0026ndash;144.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eWhitacre MM, Stein R. Sources of error with use of Goldmann-type tonometers. \u003cem\u003eSurv Ophthalmol.\u003c/em\u003e 1993;38:1\u0026ndash;30.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKaufmann C, Bachmann LM, Thiel MA. Intraocular pressure measurements using dynamic contour tonometry after laser in situ keratomileusis. \u003cem\u003eInvest Ophthalmol Vis Sci.\u003c/em\u003e 2003;44:3790\u0026ndash;3794.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eFrenkel RP, Hong J, Shin DH. Comparison of the Tono-Pen to the Goldmann applanation tonometer. \u003cem\u003eArch Ophthalmol.\u003c/em\u003e 1988;106:750\u0026ndash;753.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBlackmore SJ. The use of contact lenses in the treatment of persistent epithelial defects. \u003cem\u003eCont Lens Anterior Eye.\u003c/em\u003e 2010;33:239\u0026ndash;244.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKhan JA, Graham CE. Effect of contact lens removal or displacement on intraocular pressure. \u003cem\u003eArch Ophthalmol.\u003c/em\u003e 1991;109:825\u0026ndash;828.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRubenstein JB, Deutsch TA. Pneumatonometry through bandage contact lenses. \u003cem\u003eArch Ophthalmol.\u003c/em\u003e 1985;103:1660\u0026ndash;1661.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMcMonnies CW. Noncontact tonometry through soft contact lenses. \u003cem\u003eAm J Optom Physiol Opt.\u003c/em\u003e 1986;63:948\u0026ndash;951.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eInsler MS, Robbins RG. Intraocular pressure by noncontact tonometry with and without soft contact lenses. \u003cem\u003eArch Ophthalmol.\u003c/em\u003e 1987;105:1358\u0026ndash;1359.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePanek WC, Boothe WA, Lee DA, Zemplenyi E, Pettit TH. Intraocular pressure measurement with the Tono-Pen through soft contact lenses. \u003cem\u003eAm J Ophthalmol.\u003c/em\u003e 1990;109:62\u0026ndash;65.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eScibilia GD, Ehlers WH, Donshik PC. The effects of therapeutic contact lenses on intraocular pressure measurement. \u003cem\u003eCLAO J.\u003c/em\u003e 1996;22:262\u0026ndash;265.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLim L, Tan DT, Chan WK. Therapeutic use of Bausch \u0026amp; Lomb PureVision contact lenses. \u003cem\u003eCLAO J.\u003c/em\u003e 2001;27(4):179\u0026ndash;185.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMontero J, Sparholt J, Mely R. Retrospective case series of therapeutic applications of a lotrafilcon A silicone hydrogel soft contact lens. \u003cem\u003eEye Contact Lens\u003c/em\u003e. 2003;29(Suppl 1):S54\u0026ndash;S56; discussion S57\u0026ndash;S59, S192\u0026ndash;S194.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLim L, Ng TP, Tan DT. Accurate intraocular pressure measurement in contact lens wearers with normal pressures. \u003cem\u003eCLAO J.\u003c/em\u003e 1997;23(2):130\u0026ndash;133.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMcMonnies CW. Noncontact tonometry through soft contact lenses. \u003cem\u003eAm J Optom Physiol Opt.\u003c/em\u003e 1986;63(12):948\u0026ndash;951.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePatel S, Illahi W. Non-contact tonometry over soft contact lenses: effect of contact lens power on the measurement of intraocular pressure. \u003cem\u003eCont Lens Anterior Eye.\u003c/em\u003e 2004;27(1):33\u0026ndash;37.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eInsler MS, Robbins RG. Intraocular pressure by noncontact tonometry with and without soft contact lenses. \u003cem\u003eArch Ophthalmol.\u003c/em\u003e 1987;105(10):1358\u0026ndash;1359.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eFırat PG, Cankaya C, Doganay S, Cavdar M, Duman S, Ozsoy E, Koc B. The influence of soft contact lenses on intraocular pressure measurement. \u003cem\u003eEye (Lond)\u003c/em\u003e. 2012;26(2):278\u0026ndash;282.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMark LK, Asbell PA, Torres MA, Failla SJ. Accuracy of intraocular pressure measurements with two different tonometers through bandage contact lenses. \u003cem\u003eCornea.\u003c/em\u003e 1992;11(4):277\u0026ndash;281.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Goldman applanation tonometry, non-contact tonometry, Pascal dynamic contour tonometry, Tono-Pen, Intraocular pressure, soft contact lens","lastPublishedDoi":"10.21203/rs.3.rs-7972795/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7972795/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003ePurpose: \u003c/strong\u003eTo investigate the effect of soft contact lens wear on intraocular pressure (IOP) measurements obtained using non-contact tonometry (NCT), Pascal dynamic contour tonometry (Pascal-DCT), and the Tono-Pen.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e Twenty-nine eyes of 29 healthy volunteers were included in the study. Following a routine ophthalmologic examination, central corneal thickness was measured using an ultrasonic pachymeter. Intraocular pressure (IOP) was measured before and after soft contact lens application using NCT, Pascal-DCT, and the Tono-Pen in random order. The differences between pre- and post–soft contact lens measurements were statistically analyzed using the paired t-test.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e The mean age of the 29 healthy volunteers who participated in the study was 52.6 ± 15.4 years (range, 21–73 years). Corneal thickness measurements in all participants ranged from 506 µm to 610 µm (mean, 557.4 ± 31.6 µm). Before soft contact lens application, mean intraocular pressure (IOP) values obtained with Goldmann applanation tonometry (GAT), NCT, Pascal-DCT, and Tono-Pen were 16.1 ± 2.8 mmHg, 16.7 ± 3.8 mmHg, 17.7 ± 2.6 mmHg, and 17.2 ± 3.6 mmHg, respectively (P = 0.6). After soft contact lens application, IOP values measured with NCT, Pascal-DCT, and Tono-Pen were 14.4 ± 3.8 mmHg, 16.5 ± 2.8 mmHg, and 16.9 ± 3.8 mmHg, respectively. IOP values measured with NCT and Pascal-DCT were found to be significantly lower after lens application (P \u0026lt; 0.01 for both). Although IOP values measured with the Tono-Pen were also lower after lens application, the difference was not statistically significant (P = 0.33).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion:\u003c/strong\u003e In this study, we demonstrated that IOP can be reliably measured using the NCT, Tono-Pen, and Pascal-DCT in a limited number of participants. However, it should be kept in mind that lower IOP values are obtained when measurements are performed with the NCT and Pascal-DCT without removing the soft contact lens. Although the Tono-Pen also yields slightly lower readings in eyes wearing a soft contact lens, it should be noted that the Tono-Pen appears to be the most accurate device for measuring IOP without lens removal.\u003c/p\u003e","manuscriptTitle":"Effect of Contact Lenses on Measurements by Non-Contact tonometry, Dynamic Contour Tonometry, and Tono-Pen","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-30 08:53:54","doi":"10.21203/rs.3.rs-7972795/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"509e6da3-e7c4-45a3-8a4c-0c5981698e84","owner":[],"postedDate":"October 30th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-10-30T08:54:05+00:00","versionOfRecord":[],"versionCreatedAt":"2025-10-30 08:53:54","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7972795","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7972795","identity":"rs-7972795","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}