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A novel technique of contrast-enhanced optical coherence tomography imaging in evaluation of clearance of lipids in human tears.

Napoli PE, Coronella F, Satta GM, Fossarello M - PLoS ONE (2014)

Bottom Line: The differences in the clearance of lipids among the four groups as well as the correlations between symptom questionnaire score, standardized visual scale test, fluorescein break-up time, ocular surface fluorescein staining score, Schirmer I test scores were found to be statistically significant.This new technique of contrast-enhanced OCT imaging of the tear film following lipid-based tracer instillation provides a measure of the clearance of lipids.An improvement of the clinician's ability in the diagnosis and understanding of abnormalities of the ocular surface may be achieved by this simple approach.

View Article: PubMed Central - PubMed

Affiliation: Department of Surgical Sciences, Eye Clinic, University of Cagliari, Cagliari, Italy.

ABSTRACT

Purpose: The aim of this work was to gather preliminary data in different conditions of healthy eyes, aqueous tear deficient dry eyes, obstructive meibomian gland disease (MGD) and non-obvious obstructive MGD (NOMGD) individuals, using a new, contrast-enhanced optical coherence tomography (OCT) imaging method to evaluate the clearance of lipids in human tears.

Methods: Eighty-two adult patients presenting with complaints of ocular irritation were studied for abnormalities of the ocular surface and classified as healthy (n = 21), aqueous tear deficient dry eyes (n = 20), obstructive MGD (n = 15) and NOMGD (n = 26) individuals. A lipid-based tracer, containing an oil-in-water emulsion, was used to obtain an enhanced OCT imaging of the lower tear meniscus. After instillation, a dramatic initial increase of reflectivity of the lower tear meniscus was detected by OCT, followed by a decay back to baseline values over time. Based on this finding, the clearance of lipids was measured in real-time by Fourier-domain anterior segment OCT.

Results: The differences in the clearance of lipids among the four groups as well as the correlations between symptom questionnaire score, standardized visual scale test, fluorescein break-up time, ocular surface fluorescein staining score, Schirmer I test scores were found to be statistically significant. The individual areas under the curve of the clearance of lipids calculated by the receiver operating characteristic curve technique ranged from 0.66 to 0.98, suggesting reliable sensitivity and specificity of lipid-enhanced OCT imaging.

Conclusions: This new technique of contrast-enhanced OCT imaging of the tear film following lipid-based tracer instillation provides a measure of the clearance of lipids. The quantitative values found are in agreement with other methods of evaluation of the lacrimal system. An improvement of the clinician's ability in the diagnosis and understanding of abnormalities of the ocular surface may be achieved by this simple approach.

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Related in: MedlinePlus

Association between OCT reflectivity and amount of lipids.Vertical, 3-mm OCT scans of the lower tear meniscus. The lipid-based tracer containing different concentrations of castor oil (0.5%, 0.25%, 0.125%, and 0.06%) or saline solution were instilled in five subjects (A, B, C, D, and E, respectively). OCT imaging revealed a positive correlation between the signal intensity detected by OCT and lipids concentration. At baseline (F), the reflectivity in the lower tear meniscus was nearly undetectable.
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pone-0109843-g001: Association between OCT reflectivity and amount of lipids.Vertical, 3-mm OCT scans of the lower tear meniscus. The lipid-based tracer containing different concentrations of castor oil (0.5%, 0.25%, 0.125%, and 0.06%) or saline solution were instilled in five subjects (A, B, C, D, and E, respectively). OCT imaging revealed a positive correlation between the signal intensity detected by OCT and lipids concentration. At baseline (F), the reflectivity in the lower tear meniscus was nearly undetectable.

Mentions: A preliminary experiment was performed to test the association between OCT reflectivity and the amount of lipids. Immediately after instillation of 35 µl of tracer containing various concentrations of castor oil (0.5%, 0.25%, 0.125%, 0.06%) or saline solution (35 µl, Blu Sal, Sooft, Italy) into five subjects' eyes was performed OCT imaging. Thus, a positive correlation between OCT reflectivity and lipids concentration was revealed (fig 1). Castor oil concentration of 0.50% offered the greatest clarity of details and, therefore, was used as tracer. Accordingly, the tracer (castor oil 0.5%) was detected by OCT as a dramatic initial increase of reflectivity in the lower tear meniscus, followed by a decay back to baseline values over time (fig 2). In this way, we obtained a lipid-enhanced OCT imaging. No signs of inflammation or damage were detected either immediately or after 24h.


A novel technique of contrast-enhanced optical coherence tomography imaging in evaluation of clearance of lipids in human tears.

Napoli PE, Coronella F, Satta GM, Fossarello M - PLoS ONE (2014)

Association between OCT reflectivity and amount of lipids.Vertical, 3-mm OCT scans of the lower tear meniscus. The lipid-based tracer containing different concentrations of castor oil (0.5%, 0.25%, 0.125%, and 0.06%) or saline solution were instilled in five subjects (A, B, C, D, and E, respectively). OCT imaging revealed a positive correlation between the signal intensity detected by OCT and lipids concentration. At baseline (F), the reflectivity in the lower tear meniscus was nearly undetectable.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4219675&req=5

pone-0109843-g001: Association between OCT reflectivity and amount of lipids.Vertical, 3-mm OCT scans of the lower tear meniscus. The lipid-based tracer containing different concentrations of castor oil (0.5%, 0.25%, 0.125%, and 0.06%) or saline solution were instilled in five subjects (A, B, C, D, and E, respectively). OCT imaging revealed a positive correlation between the signal intensity detected by OCT and lipids concentration. At baseline (F), the reflectivity in the lower tear meniscus was nearly undetectable.
Mentions: A preliminary experiment was performed to test the association between OCT reflectivity and the amount of lipids. Immediately after instillation of 35 µl of tracer containing various concentrations of castor oil (0.5%, 0.25%, 0.125%, 0.06%) or saline solution (35 µl, Blu Sal, Sooft, Italy) into five subjects' eyes was performed OCT imaging. Thus, a positive correlation between OCT reflectivity and lipids concentration was revealed (fig 1). Castor oil concentration of 0.50% offered the greatest clarity of details and, therefore, was used as tracer. Accordingly, the tracer (castor oil 0.5%) was detected by OCT as a dramatic initial increase of reflectivity in the lower tear meniscus, followed by a decay back to baseline values over time (fig 2). In this way, we obtained a lipid-enhanced OCT imaging. No signs of inflammation or damage were detected either immediately or after 24h.

Bottom Line: The differences in the clearance of lipids among the four groups as well as the correlations between symptom questionnaire score, standardized visual scale test, fluorescein break-up time, ocular surface fluorescein staining score, Schirmer I test scores were found to be statistically significant.This new technique of contrast-enhanced OCT imaging of the tear film following lipid-based tracer instillation provides a measure of the clearance of lipids.An improvement of the clinician's ability in the diagnosis and understanding of abnormalities of the ocular surface may be achieved by this simple approach.

View Article: PubMed Central - PubMed

Affiliation: Department of Surgical Sciences, Eye Clinic, University of Cagliari, Cagliari, Italy.

ABSTRACT

Purpose: The aim of this work was to gather preliminary data in different conditions of healthy eyes, aqueous tear deficient dry eyes, obstructive meibomian gland disease (MGD) and non-obvious obstructive MGD (NOMGD) individuals, using a new, contrast-enhanced optical coherence tomography (OCT) imaging method to evaluate the clearance of lipids in human tears.

Methods: Eighty-two adult patients presenting with complaints of ocular irritation were studied for abnormalities of the ocular surface and classified as healthy (n = 21), aqueous tear deficient dry eyes (n = 20), obstructive MGD (n = 15) and NOMGD (n = 26) individuals. A lipid-based tracer, containing an oil-in-water emulsion, was used to obtain an enhanced OCT imaging of the lower tear meniscus. After instillation, a dramatic initial increase of reflectivity of the lower tear meniscus was detected by OCT, followed by a decay back to baseline values over time. Based on this finding, the clearance of lipids was measured in real-time by Fourier-domain anterior segment OCT.

Results: The differences in the clearance of lipids among the four groups as well as the correlations between symptom questionnaire score, standardized visual scale test, fluorescein break-up time, ocular surface fluorescein staining score, Schirmer I test scores were found to be statistically significant. The individual areas under the curve of the clearance of lipids calculated by the receiver operating characteristic curve technique ranged from 0.66 to 0.98, suggesting reliable sensitivity and specificity of lipid-enhanced OCT imaging.

Conclusions: This new technique of contrast-enhanced OCT imaging of the tear film following lipid-based tracer instillation provides a measure of the clearance of lipids. The quantitative values found are in agreement with other methods of evaluation of the lacrimal system. An improvement of the clinician's ability in the diagnosis and understanding of abnormalities of the ocular surface may be achieved by this simple approach.

Show MeSH
Related in: MedlinePlus