The Adsorption of Major Tear Film Lipids In Vitro to Various Silicone Hydrogels over Time

Carney, Fiona; Nash, Walter L.; Sentell, Karen B.

doi:10.1167/iovs.07-0376

Cited by 92 publications

(81 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The observations from the in vitro and ex vivo experimentation in our study are consistent with the in vitro results reported by Carney et al 37 and Iwata et al, 38 who also found that considerably more cholesterol was associated with galyfilcon A lenses than with lotrafilcon B lenses. Carney et al labeled cholesterol with NBD (7-nitrobenz-2-oxa-2,3-diazol-4-yl), and incubated various lens materials for 14 hours in 1.75 g/mL, after which it was read with a fluorescence counter.…”

Section: Discussionsupporting

confidence: 93%

“…When comparing the in vitro data from all three studies at about the same time point (2.5-3 days), our method recovered 1.58 g/lens of cholesterol oleate from lotrafilcon B after incubation in a 5.7 g/mL cholesterol oleate solution, whereas Carney et al 37 measured approximately 0.75 g/lens of cholesterol on the lens after incubation in 1.75 g/mL of cholesterol solution. Iwata et al 38 recovered less than 0.2 g/lens of cholesterol palmitate (cholesterol ester) from lotrafilcon B lenses soaked in 30 g/mL solution.…”

Section: Discussionmentioning

confidence: 83%

“…Indeed, others have attempted to examine cholesterol deposited on contact lenses by using different methods. 24,34,35,37 However, this attempt may be the first to quantify the total amount of cholesterol and cholesterol esters extracted from contact lenses via an enzymatic reaction assay, although the method can be applied to the quantification of cholesterol from tears and/or meibum, as well.…”

Section: Discussionmentioning

confidence: 99%

See 2 more Smart Citations

Enzymatic Quantification of Cholesterol and Cholesterol Esters from Silicone Hydrogel Contact Lenses

Pucker¹,

Thangavelu²,

Nichols³

2010

Invest. Ophthalmol. Vis. Sci.

View full text Add to dashboard Cite

PURPOSE. The purpose of this work was to develop an enzymatic method of quantification of cholesterol and cholesterol esters derived from contact lenses, both in vitro and ex vivo. METHODS. Lotrafilcon B (O2 Optix; CIBA Vision, Inc., Duluth, GA) and galyfilcon A (Acuvue Advance; Vistakon, Inc., Jacksonville, FL) silicone hydrogel contact lenses were independently incubated in cholesterol oleate solutions varying in concentrations. After incubation, the lenses were removed and underwent two separate 2:1 chloroform-methanol extractions. After in vitro studies, 10 human subjects wore both lotrafilcon B and galyfilcon A contact lenses for 7 days. The lenses also underwent two separate 2:1 chloroform-methanol extractions. All in vitro and ex vivo samples were quantified with a cholesterol esterase enzymatic reaction. RESULTS. Calibration curves from quantifications of in vitro contact lens samples soaked in successively decreasing concentrations of cholesterol oleate yielded coefficients of determination (R 2 ) of 0.99 (lotrafilcon B) and 0.97 (galyfilcon A). For in vitro contact lens samples, galyfilcon A was associated with an average cholesterol oleate extraction of 39.85 Ϯ 48.65 g/lens, whereas lotrafilcon B was associated with 5.86 Ϯ 3.36 g/lens (P ϭ 0.05) across both extractions and all incubation concentrations. For ex vivo contact lens samples, there was significantly more cholesterol and cholesterol esters deposited on galyfilcon A (5.77 Ϯ 1.87 g/lens) than on lotrafilcon B (2.03 Ϯ 1.62 g/lens; P ϭ 0.0005). CONCLUSIONS. This is an efficient and simple method of quantifying total cholesterol extracted from silicone hydrogel contact lenses and, potentially, the meibum and/or tear film. Certain silicone hydrogel materials demonstrate more affinity for cholesterol and its esters than do others. (Invest Ophthalmol Vis Sci.

show abstract

Section: Discussionsupporting

confidence: 93%

Section: Discussionmentioning

confidence: 83%

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Enzymatic Quantification of Cholesterol and Cholesterol Esters from Silicone Hydrogel Contact Lenses

Pucker¹,

Thangavelu²,

Nichols³

2010

Invest. Ophthalmol. Vis. Sci.

View full text Add to dashboard Cite

show abstract

“…44 There were no differences in the TSQ after seven days of lens wear compared with the first day of wear, neither for the hydrogel nor for the silicone hydrogel lenses. This was in spite of the fact that group-4 hydrogels (high water content ionic materials) are known to significantly accumulate lysozyme deposits [45][46][47][48] and silicone hydrogel lenses are prone to lipid accumulation [48][49][50][51] over contact lens wearing time. One of the more interesting findings of this study was a slight, but statistically significant improvement in TSQ during the first day of silicone hydrogel lens wear.…”

Section: Discussionmentioning

confidence: 99%

Tear Film Surface Quality with Soft Contact Lenses Using Dynamic Videokeratoscopy

Kopf

Iskander

et al. 2008

Journal of Optometry

View full text Add to dashboard Cite

PURPOSE:To investigate changes in tear film surface quality after commencing soft contact lens wear. METHODS: Tear film surface quality (TSQ) was assessed during the interblink period using dynamic videokeratoscopy at 25 Hz. A quantitative value of TSQ is derived for each raw Placido ring image. Eleven young subjects with normal tear characteristics participated in the study. Dynamic videokeratoscopy was taken three times per day; in the morning, at lunchtime, and in the afternoon. This was done on two baseline days (bare eye) and on the first and seventh days of lens wear for a conventional hydrogel lens and following a week of no lens wear, for a further week of silicone hydrogel lens wear. Additionally clinical tests to assess TSQ were conducted and subjects were also asked to rate the subjective dryness of their eyes. RESULTS: All lens wear measurements showed a significant worsening of TSQ compared to bare eye measurements (repeated measures ANOVA, P<0.01). A significant diurnal change was found on the first day of silicone hydrogel contact lens wear, where TSQ improved during the day (P=0.045). However, no diurnal changes were found in TSQ for the other lens wearing days or for the bare eye condition (P>0.05). The subjective rating of dryness correlated with TSQ values (Pearson's r=0.62, P<0.05) for the bare eye condition, but not during contact lens wear. TSQ derived from the right and left bare eyes of the same individuals showed a significant correlation (Pearson's r=0.61, P<0.05). CONCLUSIONS: The measurement of TSQ using dynamic videokeratoscopy differentiates between bare eye and lens wearing conditions. It also shows a small systematic improvement in tear surface quality during the first day of silicone hydrogel lens wear and a significant association with subjective dryness for the bare eye condition. (J Optom 2008;1:14-21 ©2008 Spanish Council of Optometrists) KEY WORDS: high speed videokeratoscopy; tear film; dry eye; contact lens. RESUMEN OBJETIVO:Investigar los cambios en la calidad de la superficie de la película lagrimal tras empezar a utilizar lentes de contacto blandas. MÉTODOS: Se evaluó la calidad de la superficie de la película lagrimal (CSPL) durante el periodo comprendido entre dos parpadeos consecutivos utilizando videoqueratoscopia (topografía corneal estándar) dinámica a 25 Hz. Para cada imagen registrada de los anillos de Plácido se derivó un valor cuantitativo de la CSPL. En el estudio participaron once sujetos jóvenes cuya lágrima presentaba características normales. Se realizaron medidas de videoqueratoscopia dinámica tres veces al día: por la mañana, a la hora de comer y por la tarde. Estas medidas se llevaron a cabo primero, en dos días distintos, para recabar datos de referencia (ojo desnudo, sin lente de contacto); posteriormente, el primer y el séptimo día de uso de una lente de contacto convencional de hidrogel y finalmente, y tras una semana sin utilizar lentes, se realizaron medidas el primer y el séptimo día de uso de una lente de hidrogel de silicona. De maner...

show abstract

“…Research on conventional poly-HEMA-based lens materials has shown that the deposition of lysozyme and albumin depends upon the polymer's composition (Bohnert et al, 1988), charge (Garrett et al, 2000;Soltys-Robitaille et al, 2001) and water content (Garrett et al, 1999). Silicone-hydrogel materials give rise to different deposition profiles to those associated with the use of conventional poly-HEMA hydrogel lenses in that they induce less protein deposition and more lipid deposition (Jones et al, 2003;Subbaraman et al, 2006;Carney et al, 2008). Surface roughness also need to be considered since deposits are more likely to form on imperfections of the lens surface (Hosaka et al, 1983).…”

Section: Introductionmentioning

confidence: 99%

Hydrogel Contact Lenses Surface Roughness and Bacterial Adhesion

Giráldez¹,

Yebra‐Pimentel²

2012

Ocular Diseases

View full text Add to dashboard Cite

The Adsorption of Major Tear Film Lipids In Vitro to Various Silicone Hydrogels over Time

Cited by 92 publications

References 31 publications

Enzymatic Quantification of Cholesterol and Cholesterol Esters from Silicone Hydrogel Contact Lenses

Enzymatic Quantification of Cholesterol and Cholesterol Esters from Silicone Hydrogel Contact Lenses

Tear Film Surface Quality with Soft Contact Lenses Using Dynamic Videokeratoscopy

Hydrogel Contact Lenses Surface Roughness and Bacterial Adhesion

Contact Info

Product

Resources

About