Tear Film Classification in Interferometry Eye Images Using Phylogenetic Diversity Indexes and Ripley's K Function.

Dry eye syndrome is one of the most frequently reported eye diseases in ophthalmological practice. The diagnosis of this disease is a challenging task due to its multifactorial etiology. One of the most applied tests is the manual classification of tear film images captured with the Doane interferometer. The interference phenomena in these images can be characterized as texture patterns, which can be automatically classified into one of the following categories: strong fringes, coalescing strong fringes, fine fringes, coalescing fine fringes, and debris. This work presents a method for classifying tear film images based on texture analysis using phylogenetic diversity indexes and Ripley's K function. The proposed method consists of six main steps: acquisition of the image dataset; segmentation of the region of interest; feature extraction using phylogenetic diversity indexes and Ripley's K function; feature selection using Greedy Stepwise; classification using the algorithms Support Vector Machine (SVM), Random Forest (RF), Naive Bayes (NB), Multilayer Perceptron (MLP), Random Tree (RT) and Radial Basis Function Network (RBFNet); and (6) validation of results. The best result, using the RF classifier, we obtained classification rates higher than 99% of accuracy with 0.843% of standard deviation, 0.999 of the area under the Receiver Operating Characteristics (ROC) curve, 0.995 of Kappa and 0.996 of F-Measure. The experimental results demonstrate that the proposed method is promising and can potentially be used by experts to accurately diagnose dry eye syndrome in tear film images.

Real dynamic assessment of tear film optical quality for monitoring and early prevention of dry eye.

To evaluate real dynamic assessment of tear film optical quality for monitoring and prevention of dry eye.Right eyes of 62 normal and 39 dry eye subjects were included. Dynamic measurement of objective scatter index (OSI) was performed by using the Optical Quality Analysis System II (OQAS II), correlation coefficient between OSI and time (CCOT) was calculated. According to whether the CCOT was significantly ascending, normal and dry eye groups were further subdivided for comparison. By using Scheimpflug-Placido topographer, non-invasive tear break-up time (NITBUT) was recorded, and a 2-dimensional precorneal tear film map was reconstructed and divided into central, middle, and peripheral corneal zones, distribution of tear break-up spots in the 3 corneal zones were analyzed.The numbers of tear break-up spots were higher in all the 3 corneal zones of the dry eye subjects (P < .01), when compared with the normal subjects. The Dry Eye subjects with ascending CCOT had the shortest NITBUT (P < .001-.034) and the most tear break-up spots over the whole cornea (P < .001-.044). Between the dry eye subjects with non-ascending CCOT and those with ascending CCOT, difference of tear break-up spots was found significant only in the peripheral corneal zone (P < .01).Non-ascending and ascending CCOT of dry eye patients reflect different stability of tear film. Real dynamic assessment of tear film optical quality is potential for monitoring and early prevention of dry eye.

Parameter Estimation for Evaporation-Driven Tear Film Thinning.

Many parameters affect tear film thickness and fluorescent intensity distributions over time; exact values or ranges for some are not well known. We conduct parameter estimation by fitting to fluorescent intensity data recorded from normal subjects' tear films. The fitting is done with thin film fluid dynamics models that are nonlinear partial differential equation models for the thickness, osmolarity and fluorescein concentration of the tear film for circular (spot) or linear (streak) tear film breakup. The corresponding fluorescent intensity is computed from the tear film thickness and fluorescein concentration. The least squares error between computed and experimental fluorescent intensity determines the parameters. The results vary across subjects and trials. The optimal values for variables that cannot be measured in vivo within tear film breakup often fall within accepted experimental ranges for related tear film dynamics; however, some instances suggest that a wider range of parameter values may be acceptable.

Label-Free Surface-Enhanced Raman Spectroscopy Biosensor for On-Site Breast Cancer Detection Using Human Tears.

Surface-enhanced Raman scattering (SERS) is an ultrasensitive molecular screening technique with greatly enhanced Raman scattering signals from trace amounts of analytes near plasmonic nanostructures. However, research on the development of a sensor that balances signal enhancement, reproducibility, and uniformity has not yet been proposed for practical applications. In this study, we demonstrate the potential of the practical application for detecting or predicting asymptomatic breast cancer from human tears using a portable Raman spectrometer with an identification algorithm based on multivariate statistics. This potentiality was realized through the fabrication of a plasmonic SERS substrate equipped with a well-aligned, gold-decorated, hexagonal-close-packed polystyrene (Au/HCP-PS) nanosphere monolayer that provided femtomole-scale detection, giga-scale enhancement, and <5% relative standard deviation for reliability and reproducibility, regardless of the measuring site. Our results can provide a first step toward developing a noninvasive, real-time screening technology for detecting asymptomatic tumors and preventing tumor recurrence.

Dynamic assessment of the tear film muco-aqueous and lipid layers using a novel tear film imager (TFI).

PURPOSE: The objective of the study was to assess a new technology, the tear film imager (TFI), which can dynamically image the muco-aqueous and lipid layers. METHODS: Prospective pilot case series of individuals with and without dry eye (DE). Two sequential images were obtained with the TFI. Measurements were assessed for reproducibility and compared with clinically derived DE metrics. Individuals were grouped into DE categories based on signs of DE. RESULTS: 49 patients participated in the study with a mean age of 58.8 years (SD 15.9) and a female majority (69%). Reproducibility of the muco-aqueous layer thickness (MALT) was excellent (r=0.88). MALT measurements significantly correlated with the Schirmer score (r=0.31). Lipid break up time (LBUT) as measured by the TFI significantly correlated with the clinical measure of tear break up time (TBUT) (r=0.73). MALT and LBUT were significantly thinner and shorter, respectively, in the DE groups (mild-moderate and severe) compared with the control group. When comparing TFI parameters to clinically assessed signs, sensitivity of the device was 87% and specificity was 88%. CONCLUSION: The TFI is the first machine capable of reproducibly measuring muco-aqueous thickness in human subjects which correlates with Schirmer score. In parallel, it assesses other important aspects of tear film function which correlate with clinician assessed DE metrics.

NONINVASIVE TEAR FILM BREAK-UP TIME ASSESSMENT USING HANDHELD LIPID LAYER EXAMINATION INSTRUMENT.

The aim was to determine feasibility and reliability of noninvasive tear break-up time (NIBUT) assessment using handheld lipid layer examination instrument, and to compare it with standard tear break-up time (TBUT) test. Fifty patients were enrolled, 31 with and 19 without dry eye symptoms. Schein questionnaire was used to assess dry eye symptoms. During examination, three NIBUT measurements were performed on each eye using handheld instrument, followed by three TBUT measurements. Receiver operating characteristic curves, sensitivity, specificity and logistic regression analysis were generated. Median NIBUT values were significantly shorter in dry eye symptom group than in control group in all three measurements (9, 8 and 8 s vs. 21, 22 and 21 s; p<0.001). TBUT values showed no significant difference between the groups in the first measurement (p=0.053), but the values were significantly shorter in dry eye symptom group in second and third measurements (p=0.020). The cutoff value to distinguish patients with symptoms of dry eye from control group was 12 seconds for NIBUT and 8 seconds for TBUT, with NIBUT having significantly higher sensitivity, specificity, area under the receiver operating characteristic curve and positive predictive value. NIBUT, measured by handheld lipid layer examination instrument, was superior to TBUT in detecting dry eye.

TMIS: a new image-based software application for the measurement of tear meniscus height.

PURPOSE: To present a new automated image recognition software for the measurement of tear meniscus height (TMH) and investigate its correlation and efficacy compared with an open-source software (NIH ImageJ) and manual evaluation. METHODS: A total of 520 slit lamp photographs, among which 276 were in ×16 magnification and 244 were ×40 magnified, captured from 138 eyes of 69 healthy subjects were assessed for TMH by the new automated Tear Meniscus Identification Software (TMIS), ImageJ and human graders. Images processing of TMIS included filtration, recognition and measurement of slit lamp photographs under certain algorithm, which output two measurement patterns, TMISM ax and TMISM ean . TMH measured by ImageJ software, considered as the reference value, was conducted by a masked observer while four masked ophthalmologists performed the manual evaluation. RESULTS: In both magnifications, TMH measured by TMISM ean showed similar values with ImageJ while manual evaluation demonstrated underestimated results, and a strong correlation was detected between TMIS and ImageJ. In ×16 magnified photographs, manually obtained TMH revealed a higher correlation with ImageJ, whereas a notably stronger correlation of TMIS with ImageJ was observed in ×40 photographs. Correspondingly, the accuracy for both TMISM ax and TMISM ean appeared to be lower than most doctors in ×16 slit lamp images, in contrast to a better precision of TMISM ean in ×40 ones. CONCLUSION: The new software displayed high accuracy and efficacy in ×40 magnification and TMISM ean pattern, suggesting the possibility of this automated TMH measurement platform to be a valid tool in dry eye screening and follow-up practice.

Unified approach to tear film surface analysis with high-speed videokeratoscopy.

Placido disk videokeratoscopy, when used in a dynamic acquisition mode, can be utilized for noninvasive assessment of tear film quality. The different commercially available videokeratoscopes that incorporate an automatic option to evaluate tear film do not provide consistent measurements due to differences in their designs as well as differences in the algorithms used to analyze the images. Here, a standardized algorithm that can be applied to different instruments is developed. Results show that, by applying the proposed methodology in two different videokeratoscopes, the agreement among the estimated tear film parameters considerably improves. This represents a step forward in the normalization of tear film assessment.

Tear film stability assessment by corneal reflex image degradation.

Tear film stability assessment is one of the main tests in dry eye diagnosis. However, to date, no test methodology has been adopted as the gold standard due to several reasons, such as the methods being invasive, subjective, or unfeasible for the clinical environment. In this paper, a method that overcomes the above-mentioned limitations for tear film stability measurements is presented, and is based on the degradation of corneal reflex images caused by breakups. The experimental setup, which is based on recording the corneal reflex image or the first Purkinje image, is described, as well as the method used to determine tear film stability by means of the associated breakup time (BUT) using corneal reflex image degradation. Images obtained through simulations of the experimental setup are also shown. Moreover, BUT measurements performed using both the conventional fluorescein method and the proposed method in nine healthy adults are presented. Both the experimental and simulation images show corneal reflex image degradation due to the appearance of breakups in the tear film, highlighting the potential of the method to assess tear film stability. We have shown that the corneal reflex image degrades when the tear film breaks up and, thus, the proposed method can be used to assess tear film stability.

The Bull's Eye Pattern of the Tear Film in Humans during Visual Fixation on En-Face Optical Coherence Tomography.

The aim of the study was to define and characterize the optical behavior of the tear film during visual fixation in humans on en-face optical coherence tomography (OCT). We included 20 healthy participants, 60% female, aged from 25 to 42 years (33.05 ± 4.97 [mean ± SD]) and ten patients with severe dry eye, 50% female, aged from 26 to 42 years (33.7 ± 5.31). To perform high-resolution tear film imaging, participants were asked to gaze at the internal fixation point in the spectral-domain anterior segment OCT device, and meanwhile scanning session was executed at the following time-points after blinking: at the 2nd, 3rd, 4th, 5th, and 6th second. After one hour, OCT imaging was repeated (second session) by a different operator masked to the study to verify the reliability of results. During each measuring session, a pulse oximetry was used for continuously measuring the heart rate and oxygen saturation (SpO2%). A preliminary experiment was also performed to test the absence of geometric patterns from the anterior surface of a motionless artificial eye. OCT imaging showed a motionless, stable anterior surface of the artificial eye and in dry eye patients. Conversely, in the healthy participants of the study, a bull's eye pattern of the tear film was detected by OCT at the 2nd, 3rd, 4th, 5th, and 6th second after blinking, respectively, in 45%, 60%, 45%, 60%, and 40% of OCT scans during the first session, and in 35%, 65%, 65%, 60%, and 35% of cases in the second session. Overall, a total of 200 OCT scans were performed in normal human population. A significant correlation was found between the novel tear film pattern and heart rate during the first and the second session (p < 0.01) in healthy eyes. Conversely, no correlation was revealed with SpO2%. Intraclass correlation (ICC) analysis for OCT imaging of the tear film revealed a statistically significant reproducibility of the results (ICC = 0.838; p < 0.01), indicating the high level of reliability of the method, independently of heart rate and SpO2% variables. There exists a novel, geometric pattern of the tear film during visual fixation detectable by en-face OCT, which is mainly evident as heart rate increases. Its discovery implies in turn the presence of a specific vibration (or imperceptible motion) of the tear film that, at present, is not recognized and corrected by the OCT software (in image postprocessing) unlike other eyeball movements.

Tear film analysis and evaluation of optical quality: A review of the literature.

Dry eye is a complex multifactorial disease of the ocular surface and tears. It is associated with ocular surface symptoms and is one of the most common causes for ophthalmologic consultation. Despite their frequent use in clinical practice, the usual tests to evaluate dry eye and ocular surface disease-history of symptoms, tear break-up time (TBUT), Meibomian gland evaluation, corneal fluorescein staining, Schirmer test-have shown low reproducibility and reliability. In addition, subjective symptoms are often weakly or poorly correlated with objective signs. Since the tear film is the first system through which light must pass, the optical quality of the eye is highly dependent on the homogeneity of the tear film. Various investigative methods have been developed to evaluate both the structural and functional quality of the tear film, such as corneal topography, interferometry, tear meniscus measurement, evaporation rate, tear osmolarity and even aberrometry. Some are easily accessible to clinicians, while others remain in the field of clinical research. All of these tests provide a better understanding of the pathophysiology of the tear film. This review hopes to provide an overview of the existing tests and their role in evaluating the significance of the tear film in visual function.

Effect of superior blepharoplasty on tear film: objective evaluation with the Keratograph 5M - a pilot study / Efeito da blefaroplastia superior no filme lacrimal - avaliação objetiva com ceratógrafo 5M - estudo piloto

ABSTRACT Purpose: To evaluate the effect of superior blepharoplasty on the tear film using the corneal topographer Keratograph 5M. Methods: A prospective study was performed of 27 eyes of 14 patients with superior dermatochalasis who underwent superior blepharoplasty between May and June 2016. Conservative upper eyelid blepharoplasty was performed by an en bloc resection of anterior lamellar tissue that included skin, subcutaneous tissue, and the orbicularis oculi muscle. All the eyes were imaged using the noninvasive tear breakup time tools of the Keratograph 5M. The following parameters were recorded in each patient before and 6 weeks after surgery: first noninvasive Keratograph 5M tear breakup time (the time at which the first breakup of tears occurs) and average noninvasive Keratograph 5M tear breakup time (the average time of all breakup incidents). The exclusion criteria were ophthalmological pathology, previous eyelid surgery, use of eye drops, systemic pathology, and medication that interferes with lacrimal tears. Results: The mean age of the patients was 65.1 years (range, 51-84); 86% were female. Student's t-test was used to compare the values of first and average noninvasive Keratograph 5M tear breakup times before and after surgery. The values for first noninvasive Keratograph 5M tear breakup time evaluated before and after surgery were not significantly different (9.04 and 8.71, respectively; p=0.926). The values for average noninvasive Keratograph 5M tear breakup time evaluated before and after surgery were also not significantly different (13.01 seconds and 13.14 seconds, respectively; p=0.835). Conclusions: The results of this pilot study suggest that upper blepharoplasty does not affect tear breakup time according to the objective evaluation of breakup time with the Keratograph 5M.

RESUMO Objetivos: Avaliar o efeito da blefaroplastia superior no filme lacrimal, utilizando o topógrafo de córnea Keratograph 5M. Métodos: Foi realizado estudo prospectivo de 27 olhos de 14 pacientes com dermatocálase superior submetidos à blefaroplastia superior entre maio e junho de 2016. A blefaroplastia palpebral superior conservadora foi realizada por ressecção em bloco de tecido lamelar anterior que incluiu pele, tecido subcutâneo e músculo orbicular do olho. Todos os olhos foram fotografados usando as ferramentas não-invasivas de tempo de ruptura do lacrimal do Keratograph 5M. Os seguintes parâmetros foram registrados em cada paciente antes e 6 semanas após a cirurgia: primeiro tempo não-invasivo de ruptura lacrimal de Keratograph 5M (o tempo em que ocorre o primeiro rompimento dos rasgos) e média não-invasiva do tempo de ruptura lacrimal (tempo médio de todos os incidentes de ruptura). Os critérios de exclusão foram: patologia oftalmológica, cirurgia anterior das pálpebras, uso de colírio, patologia sistêmica e medicação que interfere na ruptura lacrimal. Resultados: A idade média de idade dos pacientes foi de 65,1 anos (variação entre 51-84); 86% eram do sexo feminino. O teste t de Student foi usado para comparar os valores não-invasivos do tempo de ruptura lacrimal do Keratograph 5M e do tempo de ruptura lacrimal não invasivo do mesmo antes e após a cirurgia. Os valores não-invasivos do tempo de ruptura lacrimal do Keratograph 5M avaliados antes e após a cirurgia não foram significativamente diferentes (9,04 e 8,71, respectivamente; p=0,926). Os valores do tempo médio de ruptura lacrimal do Keratograph 5M avaliados antes e após a cirurgia, também não foram significativamente diferentes (13,01 e 13,14 segundos, respectivamente; p=0,835). Conclusão: Os resultados deste estudo piloto sugerem que a blefaroplastia superior não afeta o tempo de ruptura lacrimal de acordo com a avaliação objetiva do tempo de ruptura com o Keratograph 5M.

Effect of superior blepharoplasty on tear film: objective evaluation with the Keratograph 5M - a pilot study.

PURPOSE: To evaluate the effect of superior blepharoplasty on the tear film using the corneal topographer Keratograph 5M. METHODS: A prospective study was performed of 27 eyes of 14 patients with superior dermatochalasis who underwent superior blepharoplasty between May and June 2016. Conservative upper eyelid blepharoplasty was performed by an en bloc resection of anterior lamellar tissue that included skin, subcutaneous tissue, and the orbicularis oculi muscle. All the eyes were imaged using the noninvasive tear breakup time tools of the Keratograph 5M. The following parameters were recorded in each patient before and 6 weeks after surgery: first noninvasive Keratograph 5M tear breakup time (the time at which the first breakup of tears occurs) and average noninvasive Keratograph 5M tear breakup time (the average time of all breakup incidents). The exclusion criteria were ophthalmological pathology, previous eyelid surgery, use of eye drops, systemic pathology, and medication that interferes with lacrimal tears. RESULTS: The mean age of the patients was 65.1 years (range, 51-84); 86% were female. Student's t-test was used to compare the values of first and average noninvasive Keratograph 5M tear breakup times before and after surgery. The values for first noninvasive Keratograph 5M tear breakup time evaluated before and after surgery were not significantly different (9.04 and 8.71, respectively; p=0.926). The values for average noninvasive Keratograph 5M tear breakup time evaluated before and after surgery were also not significantly different (13.01 seconds and 13.14 seconds, respectively; p=0.835). CONCLUSIONS: The results of this pilot study suggest that upper blepharoplasty does not affect tear breakup time according to the objective evaluation of breakup time with the Keratograph 5M.

Vibration spectroscopy and body biofluids: Literature review for clinical applications.

Vibrational spectroscopy techniques such as Raman and IR (infrared) allow real-time, non-invasive and non-destructive analysis of organic compounds with a good limit-of-detection. This review aims to show the progress of clinical diagnosis and prognosis due to advances of vibrational spectroscopy techniques in biofluids through an extensive literature review. This review was performed by searching for studies using the keywords "biofluids or biological fluids" and "diagnostic techniques" in PubMed, Scopus and Google Scholar. We found 580 articles in the 1990s, 1171 articles in the 2000s and 1688 in the years from 2011. Also, a second search including "biofluids or biological fluids" and "vibrational spectroscopy" returned only one article in the 1990s, three papers in the 2000s and 18 in the years from 2011.This growth suggests a great potential of biofluid research using vibrational spectroscopy. Sample collection variations(quantity and contaminations due to contact with other body parts and their secretions) are important factors that influence sample composition. Once these factors are taken into account, spectroscopic analysis may provide the necessary information to identify a disease, lesion, tumor or infection. With the present review we aim to encourage the study of vibrational spectroscopy techniques for analysis of biofluids focusing in clinical applications. In the future, it will widely benefit clinicians, allowing new diagnostic approaches, and for patients to have early diagnosis for most every disease.

Assessment of non-invasive tear break-up time and tear meniscus height after instillation of three different formulations of anesthetic eye drops by Oculus Keratograph 5M / Avaliação do tempo de ruptura lacrimal não invasivo e da altura do menisco lacrimal após a instilação de três diferentes formulações de colírio anestésico por Oculus Keratograph 5M

Abstract Purpose: To assess the non-invasive tear break-up time (NITBUT) and tear meniscus height (TMH) after instilling the three different types of anesthetic eye drops by Oculus Keratograph 5M. Methods: In this prospective study, 85 healthy subjects (85 eyes) were randomly divided into three groups. The groups were randomly received lidocaine hydrochloride 2%, proparacaine hydrochloride 0.5%, and tetracaine hydrochloride 0.5%. The qualitative and quantitative parameters of tear film were assessed using NITBUT and TMH, respectively. In all groups, the quantity of tear film using TMH was measured in the right eye of subjects, while the quality of tear film using NITBUT was assessed in the left eye. The analysis of variance (ANOVA) was used to compare the difference between before and after the intervention. A P-value < 0.05 was considered significant. Results: Differences for TMH and NITBUT between before and after applying lidocaine hydrochloride 2% were not statistically significant (P > 0.05). The mean values of NITBUT and TMH after the instillation of proparacaine hydrochloride 0.5% showed a significant decrease than before the intervention (P < 0.05). Also, after the use of tetracaine hydrochloride 0.5%, the mean value of NITBUT was significantly increased (P < 0.05), but the mean value of TMH was significantly decreased than before the intervention (P < 0.05). Conclusion: Our study showed that lidocaine hydrochloride 2% as an anesthetic eye drops can be an appropriate choice for eye examinations due to a lack of significant effect on the quantity and quality of tear film.

Resumo Objetivo: Avaliar o tempo de ruptura lacrimal não invasivo (NITBUT) e a altura do menisco lacrimal (TMH) após instilar os três tipos diferentes de colírio anestésico pelo Oculus Keratograph 5M. Métodos: Neste estudo prospectivo, 85 indivíduos saudáveis (85 olhos) foram divididos aleatoriamente em três grupos. Os grupos receberam aleatoriamente cloridrato de lidocaína a 2%, cloridrato de proparacaína a 0.5% e cloridrato de tetracaína a 0.5%. Os parâmetros qualitativos e quantitativos do filme lacrimal foram avaliados utilizando NITBUT e TMH, respectivamente. Em todos os grupos, a quantidade de filme lacrimal utilizando TMH foi medida no olho direito dos sujeitos, enquanto a qualidade do filme lacrimal usando NITBUT foi avaliada no olho esquerdo. A análise de variância (ANOVA) foi utilizada para comparar a diferença entre antes e depois da intervenção. Um valor de P < 0.05 foi considerado significativo. Resultados: Diferenças para TMH e NITBUT entre antes e depois da aplicação de cloridrato de lidocaína a 2% não foram estatisticamente significantes (P > 0.05). Os valores médios de NITBUT e TMH após a instilação de cloridrato de proparacaína a 0.5% mostraram uma diminuição significativa do que antes da intervenção (P < 0.05). Além disso, após o uso de cloridrato de tetracaína a 0.5%, o valor médio de NITBUT foi significativamente aumentado (P < 0.05), mas o valor médio de TMH foi significativamente menor do que antes da intervenção (P < 0.05). Conclusão: Nosso estudo mostrou que o cloridrato de lidocaína a 2% como colírio anestésico pode ser uma escolha apropriada para exames oftalmológicos devido à falta de efeito significativo sobre a quantidade e a qualidade do filme lacrimal.

Partial mid-portion Achilles tear resulting in substantial improvement in pain and function in an amateur long-distance runner.

This case presents symptom resolution for a long-distance runner with chronic Achilles tendinopathy (AT), following a partial tear of his Achilles tendon. The patient reported a sudden pain during a morning run, with preserved function. Three hours postinjury, he was reviewed in a musculoskeletal clinic. An ultrasound scan confirmed a partial Achilles tear, associated with significant Doppler activity. His index of AT severity The Victorian Institute of Sports Assessment - Achilles Questionnaire (VISA-A) 4 hours postinjury was markedly higher compared with 2 weeks preinjury, indicating reduced symptom severity. A follow-up scan 4 weeks postinjury showed minimal mid-portion swelling and no signs of the tear. His VISA-A score showed continued symptom improvement. This case represents resolution of tendinopathic symptomatology post partial Achilles tear. While the natural histories of AT and Achilles tears remain unknown, this case may indicate that alongside the known role of loading, inflammation may be a secondary mediator central to the successful resolution of AT pain.

The role of "after washing imaging" in evaluation of tear drainage system by dacryoscintigraphy.

BACKGROUND: The aim of this study was to evaluate the efficacy of "after washing" imaging in interpretation of dacryoscintigraphy as a functional imaging technique used in evaluation of tearing problems. MATERIALS AND METHODS: 300 nasolacrimal systems were studied. 100 µCi of technetium-99m sodium pertechnetate as drops of activity (10 µL) were placed into the inferior fornix of each eye. Dynamic images were obtained for 15 minutes in the sitting position. "After washing" phase was done by placing a drop (10 µL) of normal saline in each eye and external ocular massage for an additional 10 minutes. The imaging patterns for each eye in the first dynamic phase and after washing phase were recorded, separately. RESULTS: First dynamic phase demonstrated a sensitivity of 97.4% and specificity of 22.6%. After washing phase showed a sensitivity of 91.2% and specificity 75.5%. After washing test, the obstruction pattern changed to "patent nasolacrimal duct" or "further progression" of the radiotracer to the nasolacrimal duct in the 25.1% and 24.4% of the nasolacrimal systems, respectively. CONCLUSIONS: After washing imaging is a useful method in dacryoscintigraphy which can improve the specificity of scan for diagnosis of lacrimal duct obstruction. It can also improve the localization of obstruction level in the lacrimal systems.

Tear film evaluation by scanning laser ophthalmoscopy during retinal imaging.

PURPOSE:: Herein, we describe a novel finding which appears as a reticular pattern on multicolor confocal scanning laser ophthalmoscopy image during routine imaging of retina and we aim to show whether there is an association between this pattern and dry eye findings. MATERIALS AND METHODS:: A total of 162 eyes of 81 patients that were scheduled for a routine retinal imaging by scanning laser ophthalmoscopy at a vitreoretinal practice underwent dry eye evaluation including corneal and conjunctival lissamine green staining, fluorescein staining, tear break-up time, and tear meniscus height measurement before acquiring any images. Then, multicolor images were taken and graded for the severity of reticular pattern. RESULTS:: Among 150 eyes of 81 patients with gradable multicolor imaging, 45 eyes (30%) had some reticular pattern on multicolor image. Severity of reticular pattern on multicolor imaging was significantly correlated with total lissamine score (rho = 0.378, p = 0.007) and tear meniscus height (rho = -0.408, p = 0.011). Furthermore, they were found to be the best set of predictors for the severity pattern on multicolor imaging (odds ratio = 1.30, 95% confidence interval = 1.01-1.37, p = 0.027 and odds ratio = 0.25, 95% confidence interval = 0.128-0.342, p < 0.001, respectively). CONCLUSION:: Reticular pattern seen on multicolor image while acquiring retinal images using scanning laser ophthalmoscopy may be related to tear film instability. Further modulations of the scanning laser ophthalmoscopy instrument will likely improve this indicator of dry eye syndrome.

Usability and reproducibility of tear meniscus values generated via swept-source optical coherence tomography and the slit lamp with a graticule method.

PURPOSE: To investigate the usability and the reproducibility of the tear meniscus values via swept-source optical coherence tomography (SS-OCT) and the conventional slit lamp microscope method with a graticule. METHODS: The right eye was examined in 90 healthy adult subjects who were grouped according to age (group 1: 20-39 years; group 2: 40-59 years; group 3: ≥60 years). The tear meniscus height (TMH) and tear meniscus area were measured using SS-OCT and TMH by the slit lamp microscope method. The reproducibility of each method was calculated using intraclass correlation coefficients (ICCs) in additionally enrolled 30 healthy young subjects. We also evaluated TMH at 3 mm from the corneal center in both temporal and nasal directions using SS-OCT. RESULTS: The mean of the TMH values measured by SS-OCT was significantly higher than those measured by the slit lamp method (328 vs. 212 µm, P < 0.001, respectively). High reproducibility was observed for each method (ICC > 0.75 for both). No statistically significant differences were found in TMH among the age groups using both SS-OCT and slit lamp methods (P = 0.985, 0.380, respectively). TMH values at both sides of the corneal center were significantly smaller than those at the corneal center (P < 0.0001). CONCLUSIONS: TMH values obtained by the slit lamp method were lower than those obtained by SS-OCT. However, both methods yielded highly reproducible TMH measurements, suggesting that they are clinically useful. Tear meniscus values did not vary by age but by measurement points in our cohort.

Application of CASIA SS-1000 Optical Coherence Tomography Tear Meniscus Imaging in Testing the Efficacy of New Strip Meniscometry in Dry Eye Diagnosis.

PURPOSE: To investigate the applicability of CASIA SS-1000 anterior-segment optical coherence tomography (AS-OCT) imaging parameters in testing the efficacy of the new strip meniscometry (SM) namely "Strip Meniscometry Tube" (SMTube) in the diagnosis of dry eyes. METHODS: Forty-three eyes of 22 patients (4 men and 18 women) with definite dry eye disease (DED) and 49 eyes of 28 normal controls (6 men and 22 women) were studied. All subjects underwent symptom questionnaires, SMTube, the Schirmer-1 test, tear film break-up time measurement, vital staining examinations, as well as tear meniscus height (TMH) and TM area (TMA) measurements using an AS-OCT system. We evaluated the cutoff values for the diagnosis of DED, looked into the correlations between TMH, TMA, and SMTube scores and checked the sensitivity and specificity of these parameters in the diagnosis of DED. RESULTS: The mean values of TMH, TMA, and SMTube scores in the patient group were 0.138±0.102 mm, 0.013±0.015 mm and 1.4±2.3 mm, whereas those for the control group were 0.27±0.10 mm, 0.033±0.025 mm and 5.8±2.8 mm, respectively. The differences between both groups were significant (P<0.001). The cutoff values of TMH, TMA, and SMTube for DED were 0.197 mm, 0.020 mm and 3.8 mm, respectively. SMTube had significant correlations with TMH (r=0.82, P<0.001) and TMA (r=0.86, P<0.001). CONCLUSIONS: The SMTube was useful in DED diagnosis, the validity of which could be effectively evaluated by the CASIA SS-1000 AS-OCT TM parameters.