scholarly journals Repeatability and Reliability of Different Diagnostic Platforms in Normal Tear Film Evaluation

2021 ◽  
Author(s):  
Swati Singh ◽  
Zarin Modiwala ◽  
Ashik Mohamed ◽  
Sayan Basu
Keyword(s):  
Interobserver Variability ◽  
Objective Assessment ◽  
Tear Film ◽  
Likelihood Estimation ◽  
Mean Difference ◽  
Healthy Individuals ◽  
Altman Analysis ◽  
Lipid Layer ◽  
Non Invasive ◽  
Tear Meniscus Height

Abstract Purpose To assess the repeatability and reliability of different commercially available diagnostic platforms in the objective assessment of normal tear film parameters. Methods Thirty healthy individuals (N = 60 eyes) had their tear film parameters (Lipid layer thickness (LLT), Tear meniscus height (TMH), Non-invasive tear break up time (NIBUT)) assessed by two observers on different occasions. The three instruments that were used are- LipiView® II, IDRA ocular surface analyzer and Oculus keratograph 5M. Bland-Altman analysis and mixed effects model with maximum likelihood estimation were used to calculate intra- and interobserver variability between the instruments. Results There were no significant intraobserver differences noted in LLT values measured with Lipiview, NIBUT using Oculus & IDRA, and Oculus TMH values. Between two observers, there were significant differences in LLT measurements (mean difference of 6.60; p = 0.002) and TMH measurements (mean difference of 0.03; p = 0.0001), obtained using IDRA but not for Oculus or Lipiview. Between instruments, all the measurements (LLT, NIBUT and TMH) were significantly different (p < 0.0001 for LLT; p = 0.002 for TMH; p < 0.0001 for NIBUT). Conclusion No two dry eye diagnostic platforms can be used interchangeably for the evaluation of the normal tear film. The NIBUT and LLT measurements using Oculus and Lipiview are more reliable than IDRA, and Oculus is more reliable than IDRA for TMH assessment.

scholarly journals Ocular Surface Cooling Rate Associated With Tear Film Characteristics and the Maximum Interblink Period

2021 ◽  
Author(s):  
Jennifer Ding ◽  
Young Hyun Kim ◽  
Sarah M Yi ◽  
Andrew D Graham ◽  
Wing Li ◽  
...  
Keyword(s):  
Ocular Surface ◽  
Tear Film ◽  
Test Strip ◽  
Surface Cooling ◽  
Non Invasive ◽  
Film Evaporation ◽  
Ocular Discomfort ◽  
Tear Meniscus Height ◽  
Film Characteristics ◽  
Breakup Time

Abstract The surface of the human eye is covered with a protective tear film that refreshes with each blink. Natural blinking occurs involuntarily, but one can also voluntarily blink or refrain from blinking. The maximum time one can refrain from blinking until the onset of discomfort is the maximum inter-blink period (MIBP). In between blinks the tear film thins and evaporates from the ocular surface. Tear film evaporation can be measured with various instruments. Infrared thermography provides a non-invasive measure of the ocular surface temperature (OST). Due to evaporation, ocular surface cooling (OSC) generally occurs when the eyes are open and exposed to the environment. The purpose of our study was to investigate the effect of OSC on the MIBP, and to investigate the association of the MIBP with tear film characteristics in subjects who do and do not exhibit OSC. The MIBP was measured simultaneously with OST over time. Non-invasive tear breakup time, tear meniscus height, tear lipid layer thickness, and Schirmer I test strip wetted lengths were measured on a day prior to the thermography visit. Subjects were divided into cooling and non-cooling groups based on OSC rate, and demographic and tear film characteristics were tested for inter-group differences. A faster rate of OSC was associated with an exponentially shorter duration of the MIBP overall and within the cooling group alone. Faster non-invasive tear breakup time was significantly associated with a shorter MIBP in both groups. These results suggest that tear film evaporation initiates a pathway that results in the onset of ocular discomfort and the stimulus to blinking. The presence of a subset of subjects with no or minimal OSC who nevertheless have a short MIBP indicates that evaporative cooling is not the only mechanism responsible for the onset of ocular discomfort.

scholarly journals An investigation of non-invasive tear break up time and tear meniscus height of keratoconic versus non-keratoconic individuals

2016 ◽  
Vol 75 (1) ◽  
Author(s):  
Deanne L. Nicholas ◽  
Wayne D.H. Gillan
Keyword(s):  
Dry Eye ◽  
Tear Film ◽  
Dry Eye Disease ◽  
Eye Disease ◽  
Non Invasive ◽  
Control Subjects ◽  
Tear Meniscus ◽  
Break Up ◽  
Tear Meniscus Height ◽  
And Control

Keratoconus is a debilitating condition where the cornea develops a conical shape rather than the characteristic round shape due to various physiological and structural changes taking place within the layers of the cornea. As a result of the pathogenesis of keratoconus, there are numerous changes that may occur within the tears of these patients. Research has shown changes in the tear metabolome, the presence of degradation products as well as loss of goblet cells into the tears. Could the changes occurring within the tear structure of these patients affect the results of various tear quantity and quality tests? Non-invasive tear break up time (NTBUT) is a diagnostic test used to determine the quality of the tear film and has been used extensively when diagnosing dry eye disease. This test is utilised in order to determine the time taken for the tear film to begin breaking apart, signalling thinning of the tears. Shorter break up times are therefore indicative of instability or changes occurring within the tear film which could be diagnostic of dry eye disease. Tear meniscus height (TMH) measurements have also been utilised in clinical practice, where these measurements provide an indication of the volume of tears contained within the upper and lower menisci. Lower tear volumes have been shown to be present in cases of dry eye disease where either tear production or tear drainage may be affected. Changes in the quality and quantity of the tear film in subjects with dry eye disease have been thoroughly investigated; however, the same cannot be said for subjects with keratoconus. Could the same findings be possible in subjects with keratoconus? Is it possible that the changes occurring within the tears of keratoconic subjects could lead to abnormal NTBUT and TMH measurements when compared to those of control subjects? Could the results of the NTBUT and TMH tests be related to one another? This study compares the NTBUT and TMH measurements of both keratoconic and control subjects by making use of a single type of instrumentation, namely the Oculus Keratograph 4 (OK4). The results of this study reveal that the values obtained for each of the two subject groups are not shown to be statistically significantly different and that there is no significant correlation between the NTBUT and TMH measurements when comparing keratoconic and control subjects.

scholarly journals Changes in Ocular Surface Disease Evaluated after Nonpenetrating Deep Sclerectomy

2021 ◽  
Author(s):  
Carlota Fuente-García ◽  
Francisco José Muñoz-Negrete ◽  
Elisabet de Dompablo-Ventura ◽  
Javier Moreno-Montañés ◽  
Gema Rebolleda
Keyword(s):  
Ocular Surface ◽  
Anterior Segment ◽  
Tear Film ◽  
Ocular Surface Disease ◽  
Control Group ◽  
Deep Sclerectomy ◽  
Ocular Surface Disease Index ◽  
Non Invasive ◽  
Group A ◽  
Tear Meniscus Height

Abstract Objective: To analyse the ocular surface changes in eyes after the withdraw of anti-glaucomatous drugs when non-penetrating deep sclerectomy (NPDS) is performed.Methods: 31 patients (33 eyes) diagnosed of glaucoma that underwent NPDS, were included in this prospective study. Control group included 33 eyes of 33 age and sex-matched volunteers. Five variables were studied with Keratograph 5M (K5M): ocular hyperaemia (OH), non-invasive tear film break-up time (NI-BUT), lower tear meniscus height (LTMH) and meibography. LTMH was also measured using the anterior segment module of Spectralis Fourier-Domain Optical Coherence Tomography (FD-OCT). Also, an evaluation of corneal and conjunctival staining was performed.In addition, patients were asked to answer two questionnaires: Ocular Surface Disease Index (OSDI) and National Eye Institute Visual Functioning Questionnaire (NEI VFQ-25) before and 6-months after surgery.Results: Before NPDS, treated eyes, showed worse objective data than healthy controls (p ≤0.049). In this group, a significant improvement was observed in the questionnaires (p< 0.001), LTMH FD-OCT (p=0.037) and LTMH K5M (p=0.025), K5M OH (p=0.003), NI-BUT (=0.022) and conjunctival and corneal staining (p<0.001). No significant differences were observed between groups in FD-OCT and K5M LTMH, NI-BUT, corneal-conjunctival staining and in the most OH sector values at 6 months(p ≥0.62).Conclusion: A significant improvement in the ocular surface was observed 6 months after NPDS, suggesting that the withdrawn of the topical anti-glaucomatous treatment has a beneficial effect.

scholarly journals Lipid composition of human meibum

2013 ◽  
Vol 72 (2) ◽  
Author(s):  
R. Schnetler ◽  
W. D. H. Gillan ◽  
G. Koorsen
Keyword(s):  
Lipid Analysis ◽  
Tear Film ◽  
Meibomian Gland ◽  
Cholesteryl Esters ◽  
Ocular Diseases ◽  
Healthy Individuals ◽  
Lipid Layer ◽  
Mucin Layer ◽  
Aqueous Layer ◽  
And Function

The structure and function of meibomian gland lipids in the tear film are highly complex. Evidence shows that the precorneal tear film consists of discrete layers: the inner mucin layer, the middle aqueous layer and the outer lipid layer. In this review we focus on the outer, biphasic lipid layer of the tear film which consists of a ‘thick’ outer, non-polar layer  and a ‘thin’ inner, polar layer. We discuss the main composition of the polar and non-polar lipids within meibum (wax esters, cholesteryl esters, mono-, di- and tri-acylglycerols, ceramides, phospholipids  et cetera). We address the composition of meibomian lipids in subjects suffering from various ocular diseases in comparison with the composition in healthy individuals. Further analysis is needed to determine whether a correlation exists between the etiology of various ocular diseases and the fluctuation on the lipids as well as to establish whether or not tear lipid analysis can be used as a diagnostic tool.

Reliability and interobserver variability of non-invasive tear film parameters

2009 ◽  
Vol 87 ◽  
pp. 0-0
Author(s):  
K KOSINA-HAGYO ◽  
A VERES ◽  
E FODOR ◽  
ZS LANG ◽  
B CSAKANY ◽  
...  
Keyword(s):  
Interobserver Variability ◽  
Tear Film ◽  
Non Invasive

scholarly journals Short Term Effect of Virtual Reality on Tear Film Stability and Ocular Discomfort

2020 ◽  
Vol 4 (1) ◽  
pp. 40-46
Author(s):  
Mohd Zulfaezal Che Azemin ◽  
Keyword(s):  
Virtual Reality ◽  
Tear Film ◽  
Film Stability ◽  
The Public ◽  
Non Invasive ◽  
Significant Difference ◽  
Ocular Discomfort ◽  
Tear Film Stability ◽  
Before And After ◽  
Tear Meniscus Height

Virtual reality (VR) has been integrated and used with smartphones as one of the digital entertainments such as in gaming and movie streaming. With emergent of various VR brands in the market, it concerns the public on the possible side effects of VR on the ocular performance specifically on tear film stability and ocular discomfort. The purpose of this study was to compare the change on non-invasive keratograph tear break-up time (NIKBUT), tear meniscus height (TMH) before and after the use of VR for 30 minutes, and to measure the ocular discomfort after the use of VR quantitatively. Thirty-two subjects were recruited in this study and all the subjects were divided randomly into two groups; VR and laptop (used as a control) groups. Each subject needed to watch a movie for 30 minutes using the respective devices. The changes of tear film stability and ocular discomfort before and after the use of the devices were then compared and the results showed that there was no significant difference (p>0.05) after 30 minutes of the use. Comparison of the ocular parameters between the devices on post-watching activities was also not significant (p>0.05). Use of VR did not give any signs of dryness to the eyes and it can be used without any discomfort even after 30 minutes usage of the devices.

scholarly journals Ocular surface cooling rate associated with tear film characteristics and the maximum interblink period

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jennifer E. Ding ◽  
Young Hyun Kim ◽  
Sarah M. Yi ◽  
Andrew D. Graham ◽  
Wing Li ◽  
...  
Keyword(s):  
Ocular Surface ◽  
Tear Film ◽  
Test Strip ◽  
Group Differences ◽  
Surface Cooling ◽  
Non Invasive ◽  
Ocular Discomfort ◽  
Tear Meniscus Height ◽  
Film Characteristics ◽  
Breakup Time

AbstractThe surface of the human eye is covered with a protective tear film that refreshes with each blink. Natural blinking occurs involuntarily, but one can also voluntarily blink or refrain from blinking. The maximum time one can refrain from blinking until the onset of discomfort is the maximum interblink period (MIBP). During the interblink period the tear film evaporates and thins from the ocular surface. Infrared thermography provides a non-invasive measure of the ocular surface temperature (OST). Due to evaporation, ocular surface cooling (OSC) generally occurs when the eyes are open and exposed to the environment. The purpose of our study was to investigate the effect of OSC rate on the MIBP, and to investigate the association of the MIBP with tear film characteristics in subjects who do and do not exhibit OSC. The MIBP was measured simultaneously with OST over time. Non-invasive tear breakup time, tear meniscus height, tear lipid layer thickness, and Schirmer I test strip wetted lengths were measured on a day prior to the thermography visit. Subjects were divided into cooling and non-cooling groups based on OSC rate, and demographic and tear film characteristics were tested for inter-group differences. A faster OSC rate was associated with an exponentially shorter duration of the MIBP overall and within the cooling group alone. Faster non-invasive tear breakup time was significantly associated with a shorter MIBP in both groups. These results suggest that tear film evaporation initiates a pathway that results in the onset of ocular discomfort and the stimulus to blinking. The presence of a subset of subjects with no or minimal OSC who nevertheless have a short MIBP indicates that evaporative cooling is not the only mechanism responsible for the onset of ocular discomfort.

A Single-Center Trial to Evaluate the Efficacy and Tolerability of Four Microneedling Treatments on Fine Lines and Wrinkles of Facial and Neck Skin in Subjects With Fitzpatrick Skin Types I-IV: An Objective Assessment Using Non-Invasive Devices and 0.33mm Microbiopsies

2021 ◽  
Author(s):  
Christine E Wamsley ◽  
Mikaela Kislevitz ◽  
Jennifer Barillas ◽  
Deniz Basci ◽  
Vishal Kandagatla ◽  
...  
Keyword(s):  
Gene Expression ◽  
Objective Assessment ◽  
Standard Of Care ◽  
Transepidermal Water Loss ◽  
Post Treatment ◽  
Non Invasive ◽  
Muscle Formation ◽  
The Face ◽  
High Resolution Ultrasonography ◽  
Elastin Gene

Abstract Background While ablative techniques have been standard of care for the treatment of fine lines and wrinkles, microneedling is a minimally invasive alternative. Objectives The purpose of this study was to assess the efficacy of microneedling on facial and neck fine lines and wrinkles. Methods 35 subjects between 44 and 65 years old with Fitzpatrick skin types I-IV received four monthly microneedling treatments over the face and neck. Subjects returned one and three months post-treatment. At every visit, high-resolution ultrasonography, optical coherence tomography, transepidermal water loss and BTC-2000 were performed. 0.33mm microbiopsies were collected pre-treatment, before the fourth treatment and three months post-treatment. Results 32 subjects (93.75% female, 6.25% male) completed all seven visits. Facial dermal and epidermal density increased 101.86% and 19.28%, respectively from baseline at three months post-treatment. Facial elasticity increased 28.2% from baseline three months post-treatment. Facial attenuation coefficient increased 15.65% and 17.33% one and three months post-treatment. At study completion, blood flow 300µm deep decreased 25.8% in the face and 42.3% in the neck. Relative collagen type III and elastin gene expression was statistically higher three months post-treatment. However, total elastin protein levels unchanged compared to baseline. 58% of biopsies extracted three months post-treatment showed dermal muscle formation, compared to baseline 15.3%. Conclusions The results illustrate the effects of microneedling treatments. Non-invasive measurements and biopsy data showed changes in skin architecture and collagen/elastin gene expression suggesting skin rejuvenation, with new extracellular matrix production and muscle formation.

scholarly journals Increased Serum Levels of Activated Caspases in Murine and Human Biliary Atresia

2021 ◽  
Vol 10 (12) ◽  
pp. 2718
Author(s):  
Omid Madadi-Sanjani ◽  
Gunnar Bohlen ◽  
Fabian Wehrmann ◽  
Julia Andruszkow ◽  
Karim Khelif ◽  
...  
Keyword(s):  
Liver Injury ◽  
Biliary Atresia ◽  
Caspase 3 ◽  
Serum Levels ◽  
Healthy Individuals ◽  
Serological Detection ◽  
Caspase Activation ◽  
Hepatocyte Apoptosis ◽  
Non Invasive ◽  
Cholestatic Diseases

In biliary atresia (BA), apoptosis is part of the pathomechanism, which results in progressive liver fibrosis. There is increasing evidence suggesting that apoptotic liver injury can be non-invasively detected by measuring the caspase activity in the serum. The purpose of this study was to investigate whether serological detection of caspase activation mirrors apoptotic liver injury in the infective murine BA-model and represents a suitable biomarker for BA in humans. Analysis showed increased caspase-3 activity and apoptosis in the livers of cholestatic BALB/c mice, which correlated significantly with caspase activation in the serum. We then investigated caspase activation and apoptosis in liver tissues and sera from 26 BA patients, 23 age-matched healthy and 11 cholestatic newborns, due to other hepatopathies. Compared to healthy individuals, increased caspase activation in the liver samples of BA patients was present. Moreover, caspase-3 activity was significantly higher in sera from BA infants compared to patients with other cholestatic diseases (sensitivity 85%, specificity 91%). In conclusion, caspase activation and hepatocyte apoptosis play an important role in experimental and human BA. We demonstrated that serological detection of caspase activation represents a reliable non-invasive biomarker for monitoring disease activity in neonatal cholestatic liver diseases including BA.

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