A New, Specular Reflection-based, Precorneal Tear Film Stability Measurement Technique in a Rabbit Model: Viscoelastic Increases Tear Film Stability

Overview

Journal Invest Ophthalmol Vis Sci

Specialty Ophthalmology

Date 2014 Jun 21

PMID 24948606

Citations 2

Authors

Derek Nankivil

Alex Gonzalez

Esdras Arrieta

Cornelis Rowaan

Mariela C Aguilar

Krystal Sotolongo

Florence A Cabot

Sonia H Yoo

Jean-Marie A Parel

Affiliations

Soon will be listed here.

Abstract

Purpose: To develop a safe, noninvasive, noncontact, continuous in vivo method to measure the dehydration rate of the precorneal tear film and to compare the effectiveness of a viscoelastic agent in maintaining the precorneal tear film to that of a balanced salt solution.

Methods: Software was designed to analyze the corneal reflection produced by the operating microscope's coaxial illumination. The software characterized the shape of the reflection, which became distorted as the precorneal tear film evaporated; characterization was accomplished by fitting an ellipse to the reflection and measuring its projected surface area. Balanced salt solution Plus (BSS+) and a 2% hydroxypropylmethylcellulose viscoelastic were used as the test agents. The tear film evaporation rate was characterized and compared over a period of 20 minutes in 20 eyes from 10 New Zealand white rabbits.

Results: The ellipse axes ratio and surface area were found to decrease initially after each application of either viscoelastic or BSS+ and then to increase linearly as the tear film began to evaporate (P < 0.001) for eyes treated with BSS+ only. Eyes treated with BSS+ required 7.5 ± 2.7 applications to maintain sufficient corneal hydration during the 20-minute test period, whereas eyes treated with viscoelastic required 1.4 ± 0.5 applications. The rates of evaporation differed significantly (P < 0.043) between viscoelastic and BSS+.

Conclusions: The shape and surface area of the corneal reflection are strongly correlated with the state of the tear film. Rabbits' corneas treated with viscoelastic remained hydrated significantly longer than corneas treated with BSS+.

Citing Articles

A Multicenter Prospective Randomized Controlled Study of a New Corneal Wetting Agent During Ophthalmologic Surgery.

Chen S, Zhang J, Tian J, Zhao C, Liu C, Sun X Ophthalmol Ther. 2023; 12(6):3211-3218.

PMID: 37768528 PMC: 10640533. DOI: 10.1007/s40123-023-00818-6.

Tripolymeric Corneal Coating Gel Versus Balanced Salt Solution Irrigation During Cataract Surgery: A Retrospective Analysis.

Giardini P, Hauranieh N, Gatto C, Tothova J Cornea. 2018; 37(4):431-435.

PMID: 29300265 PMC: 5844581. DOI: 10.1097/ICO.0000000000001480.

References

Montes-Mico R . Role of the tear film in the optical quality of the human eye. J Cataract Refract Surg. 2007; 33(9):1631-5. DOI: 10.1016/j.jcrs.2007.06.019. View

Li J, Akiyama R, Kuang K, Fischbarg J . Effects of BSS and BSS+ irrigation solutions on rabbit corneal transendothelial electrical potential difference. Cornea. 1993; 12(3):199-203. DOI: 10.1097/00003226-199305000-00003. View

Asensio I, Rahhal S, Alonso L, Palanca-Sanfrancisco J, Sanchis-Gimeno J . Corneal thickness values before and after oxybuprocaine 0.4% eye drops. Cornea. 2003; 22(6):527-32. DOI: 10.1097/00003226-200308000-00008. View

Gao L, Fan H, Cheng A, Wang Z, Lam D . The effects of eye drops on corneal thickness in adult myopia. Cornea. 2006; 25(4):404-7. DOI: 10.1097/01.ico.0000214205.29823.f6. View

. Research in dry eye: report of the Research Subcommittee of the International Dry Eye WorkShop (2007). Ocul Surf. 2007; 5(2):179-93. DOI: 10.1016/s1542-0124(12)70086-1. View

Kalyanasundaram T, Hasan M . Corneal-wetting property of lignocaine 2% jelly. J Cataract Refract Surg. 2002; 28(8):1444-5. DOI: 10.1016/s0886-3350(02)01265-8. View

Wessels I, Debarge R, Wessels D . Salvaged viscoelastic reduces irrigation frequency during cataract surgery. Ophthalmic Surg Lasers. 1998; 29(8):688-91. View

de Souza I, de Souza A, DE QUEIROZ A, Figueiredo P, Jesus R, Kara-Jose N . Influence of temperature and humidity on laser in situ keratomileusis outcomes. J Refract Surg. 2001; 17(2 Suppl):S202-4. DOI: 10.3928/1081-597X-20010302-11. View

NORN M . Desiccation of the precorneal film. I. Corneal wetting-time. Acta Ophthalmol (Copenh). 1969; 47(4):865-80. DOI: 10.1111/j.1755-3768.1969.tb03711.x. View

10.

Hwang H, Kim H . Phototoxic effects of an operating microscope on the ocular surface and tear film. Cornea. 2013; 33(1):82-90. DOI: 10.1097/ICO.0000000000000001. View

11.

Edelhauser H, Hine J, Pederson H, VAN HORN D, Schultz R . The effect of phenylephrine on the cornea. Arch Ophthalmol. 1979; 97(5):937-47. DOI: 10.1001/archopht.1979.01020010495025. View

12.

Emre S, Akkin C, Afrashi F, Yagci A . Effect of corneal wetting solutions on corneal thickness during ophthalmic surgery. J Cataract Refract Surg. 2002; 28(1):149-51. DOI: 10.1016/s0886-3350(01)01029-x. View

13.

Edelhauser H, VAN HORN D, Hyndiuk R, Schultz R . Intraocular irrigating solutions. Their effect on the corneal endothelium. Arch Ophthalmol. 1975; 93(8):648-57. DOI: 10.1001/archopht.1975.01010020614011. View

14.

Arshinoff S, Khoury E . HsS versus a balanced salt solution as a corneal wetting agent during routine cataract extraction and lens implantation. J Cataract Refract Surg. 1997; 23(8):1221-5. DOI: 10.1016/s0886-3350(97)80320-3. View

15.

Ohashi Y, Dogru M, Tsubota K . Laboratory findings in tear fluid analysis. Clin Chim Acta. 2006; 369(1):17-28. DOI: 10.1016/j.cca.2005.12.035. View

16.

Chen Y, Hirnschall N, Findl O . Comparison of corneal wetting properties of viscous eye lubricant and balanced salt solution to maintain optical clarity during cataract surgery. J Cataract Refract Surg. 2011; 37(10):1806-8. DOI: 10.1016/j.jcrs.2011.07.001. View