Electrohydrodynamic (EHD) printing has been recognized as a promising additive manufacturing technology with superior pattern resolution and economic viability. The shape of Taylor cone is deemed a ...pivotal element for the amplification of deposition efficiency, and the maintenance of consistent operational steadiness in EHD printing. The correlations between diverse operating parameters and the shape of Taylor cone are presently not well investigated. In this paper, modeling of relationships between operating parameters and the shape of Taylor cone was conducted with a backpropagation neural network (BPNN) and a genetic algorithm optimized backpropagation (GA-BP) neural network. Taylor cone semi-vertical angle and the meniscus height were employed as two indexes to characterize the shape of Taylor cone. The prediction accuracies of BPNN model and GA-BP model were 92.79 % and 95.46 %, respectively. The GA-BP model demonstrated higher precision in forecasting the shape of Taylor cone. A predictive framework for the shape of Taylor cone was proposed, which provided a practical tool for process optimization in EHD printing.
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•Two key parameters, Meniscus height and Taylor cone semi-vertical angle, were used.•BPNN and GA-BP Models were built to predict shape parameters of Taylor cone.•Both BPNN and GA-BP models had good prediction accuracy.
PurposeAccurate quantification measurement of tear meniscus is vital for the precise diagnosis of dry eye. In current clinical practice, the measurement of tear meniscus height (TMH) relies on ...doctors' manual operation. This study aims to propose a novel automatic artificial intelligence (AI) system to evaluate TMH. MethodsA total of 510 photographs obtained by the oculus camera were labeled. Three thousand and five hundred images were finally attained by data enhancement to train the neural network model parameters, and 60 were used to evaluate the model performance in segmenting the cornea and tear meniscus region. One hundred images were used to test generalization ability of the model. We modified a segmentation model of the cornea and the tear meniscus based on the UNet-like network. The output of the segmentation model is followed by a calculation module that calculates and reports the TMH. ResultsCompared with ground truth (GT) manually labeled by clinicians, our modified model achieved a Dice Similarity Coefficient (DSC) and Intersection over union (Iou) of 0.99/0.98 in the corneal segmentation task and 0.92/0.86 for the detection of tear meniscus on the validation set, respectively. On the test set, the TMH automatically measured by our AI system strongly correlates with the results manually calculated by the ophthalmologists. ConclusionsWe developed a fully automated and reliable AI system to obtain TMH. After large-scale clinical testing, our method could be used for dry eye screening in clinical practice.
Tear meniscus height (TMH) is an important clinical marker in dry eye diagnosis and management.
To evaluate the reproducibility and agreement of TMH measurements in non-clinical participants using ...the Oculus Keratograph 5 M, Medmont Meridia, and Spectral-domain optical coherence tomography (Spectralis SD-OCT).
Fifty-six participants (mean 43.8 ± 22.4 years) were recruited for this cross-sectional study. Image acquisitions were performed on the three devices, sequentially and randomized. The repeatability and reproducibility of inter-observer and inter-device analysis were performed. Repeated measures ANOVA and Bland-Altman Plots were used to evaluate the agreement between devices.
The mean TMH with the Oculus Keratograph 5 M, Medmont Meridia and Spectralis SD-OCT were 0.29 ± 0.16 mm, 0.24 ± 0.09 mm and 0.27 ± 0.16 mm, respectively. There were no significant inter-observer differences (paired t-tests,
< 0.001). All the devices exhibited good inter-observer reliability (ICC ≥ 0.877), and good repeatability (CV ≤ 16.53%). Inter-device reliability is moderate (ICC = 0.621,
< 0.001). Repeated measures ANOVA revealed that TMH measurements given by the Spectralis SD-OCT are not significantly different from the Oculus Keratograph 5 M (
= 0.19) and the Medmont Meridia (
= 0.38). TMH measurements from Oculus Keratograph 5 M were significantly higher than those from Medmont Meridia (
= 0.02). Correlations between the mean TMH and the difference in the TMH measurements were positive for Oculus Keratograph 5 M and Medmont Meridia (r
= 0.62,
< 0.001), negative for Medmont Meridia and Spectralis SD-OCT (r
= -0.59,
< 0.001), and not significant for Oculus Keratograph 5 M and Spectralis SD-OCT (r
= 0.05,
= 0.74). A strong correlation was found for TMH measured with all devices (r
= 0.55 to 0.81,
< 0.001).
The Oculus Keratograph 5 M, Medmont Meridia, and Spectralis SD-OCT provide reliable and reproducible inter-observer TMH measurements. Inter-device reliability is moderate, with a close correlation between Spectralis SD-OCT and the Oculus Keratograph 5 M. Oculus Keratograph 5 M and Medmont Meridia are repeatable devices appropriate for the measurement of TMH, but they are not interchangeable in clinical practice.
The current study investigated the normative data values and repeatability of non-invasive tear film tests using Oculus Keratograph 5M in rabbit eyes.
Triplicate analysis of tear film parameters tear ...meniscus height (TMH), non-invasive tear break up time (NIBUT), bulbar congestion, meibography of 38 healthy adults New Zealand white rabbits (mean age, 13 ± 4.7 months) was performed using Oculus keratograph 5M (K5M). Bland-Altman analysis was used for testing repeatability.
Thirty-eight rabbits (
= 76 eyes) weighing 2.5 ± 0.4 kg were studied. The mean NIBUT values of the right and left eye were 14.3 ± 5.8 and 12.3 ± 5.8 s, respectively. The mean central TMH values were 0.43 ± 0.23 and 0.33 ± 0.14 mm in the right and left eye, respectively. Meibography showed closely placed, wide meibomian glands running vertically with no distorted or gland loss areas. There were no differences between the eyes for the above parameters. Bland-Altman plot showed good repeatability for both NIBUT and TMH values.
The non-invasive tear film parameters show good repeatability using keratograph 5M and can be used as an objective parameter for rabbit ocular surface experiments.
Purpose: To evaluate changes of ocular surface dynamics using Keratograph 5M for 3 months after vitreoretinal surgery.Methods: Eighty-three patients were divided into three groups: ...phacoemulsification group, vitrectomy group, and combined group. Keratograph 5M was performed for all patients at 1 week, 1 month, and 3 months after the surgery. Ocular surface dynamics parameters measured by Keratograph 5M, including noninvasive keratograph first tear film breakup time (NifBUT), noninvasive keratograph average tear film breakup time (NiaBUT), and tear meniscus height (TMH) were compared among the three groups over time.Results: The mean age of all patients (46 men and 37 women) was 62.2 ± 8.4 years. NifBUT and NiaBUT were significantly decreased at 1 week after surgery compared to those at baseline in all three groups (all p < 0.001). NifBUT and NiaBUT in the phacoemulsification group almost recovered to the preoperative level, while those in the vitrectomy group and the combined group were still significantly less than those at baseline. NifBUT and NiaBUT in the phacoemulsification group were significantly longer than those in the vitrectomy group and the combined group at 3 months. After 1 week, TMHs were significantly higher in the vitrectomy group (p = 0.001) and the combined group (p = 0.022) than in the phacoemulsification group, while TMHs were significantly less in the vitrectomy group (p = 0.010) and the combined group (p < 0.001) than in the phacoemulsification group at 3 months after surgery.Conclusions: These results suggest that vitreoretinal surgery could induce alteration of ocular surface dynamics for 3 months. The vitrectomy group and the combined group showed tear film instability compared to the cataract surgery alone group. Patients who underwent vitreoretinal surgery experienced more severe dry eye syndrome symptoms than those who underwent cataract surgery. Thus, managing dry eye syndrome after vitreoretinal surgery should be considered important for patients.
This study aims to develop and assess an infrastructure using Python-based deep learning code for future diagnostic and management purposes related to dry eye disease (DED) utilizing smartphone ...images.
Cross-sectional study using data which was gathered in Vision Health Research Clinic.
One thousand twenty-one eye images from 734 patients were included in this article that categorizes into 70% females and 30% males, with no sex and age limit.
One specialist captured eye images using Samsung A71 (601 images) and iPhone 11 (420 images) cell phones with the flashlight on and direct gaze to the camera. These images include the area of only 1 eye (left/right).
First, our specialist did 3 different segmentations for every eye image separately for 80% of the training data. This part contains eye, lower eyelid, and iris segmentation. In 20% of test data after automated cropping of the lower eyelid margin and upscaling by 8×, the appropriate tear meniscus height segmentation will be chosen and measured using a deep learning algorithm.
The model was trained on 80% of the data and 20% of the data used for validation from both phones with different resolutions. The dice coefficient of the trained model for validation data is 98.68%, and the accuracy of the overall model is 95.39%.
It appears that this algorithm holds the potential to herald an evolution in the future of diagnosis and management of DED by homecare devices solely through smartphones.
The author(s) have no proprietary or commercial interest in any materials discussed in this article.
We aimed to elicit strong blinks among healthy video display terminal (VDT) users by periorbital transcutaneous electric nerve stimulation (TENS) and evaluate its impact on the tear fluid and visual ...task. Appropriate TENS conditions were evaluated to evoke strong blinks under minimum discomfort. Seventeen healthy VDT users with noninvasive Keratograph first breakup time (NIKf-BUT) 5-15 s and Ocular Surface Disease Index (OSDI) scores < 15 were recruited in this study. Before the trial, noninvasive Keratograph average breakup time (NIKa-BUT), tear meniscus height (TMH) and OSDI scores were evaluated. Before each TENS session, the volunteers played
Tetris
while the corresponding blink rate and
Tetris
scores were recorded. Then, the participants underwent 30 minutes of TENS, which evoked blinking of their right eye 20 times per minute.
Tetris
scores were evaluated again during TENS. The
Tetris
scores and corresponding blink rate were assessed after each TENS session while NIKa-BUT, TMH and OSDI scores were recorded after the third and sixth TENS sessions. We found that OSDI scores declined significantly after the sixth TENS (
P
= .003). The NIKa-BUT of the right eye was promoted after the sixth TENS (
P
= .02), and the TMH was higher after the third and sixth TENS in both eyes (
P
= .03,
P
= .03 for right eyes respectively,
P
= .01,
P
= .01 for left eyes respectively). There was no significant difference between the adjusted
Tetris
scores before and during TENS (
P
= .12). The blink rate before and after TENS were unaffected after 6 sessions (
P
= .61). The results indicated that periorbital TENS effectively ameliorated ocular irritation and improved tear secretion and tear film stability by eliciting strong blinks in healthy VDT users without disturbing the visual task.
The quantification of the tear meniscus height can be helpful in the diagnosis of Dry Eyes Disease. This paper presents a method for automatic quantitation of lower tear meniscus height (TMH) with ...fully convolutional neural networks (FCNN) and investigate its performance and efficacy compared to manual measurements. A total of 485 images from 217 subjects were acquired with a mainstream corneal topographer and then divided these images into the development and testing set respectively. The development set was used to train the FCNN models, while the testing set to evaluate the performance of the models. TMH of each image was assessed by the proposed method based on the corresponding segmentation mask of tear meniscus and compared against the manual results. The tear meniscus of each image in the testing set was segmented by the FCNN. Five-fold cross validation revealed an overall average intersection of Union (IoU) of 82.5 %, a F1-score of 90.1 % for tear meniscus segmentation. The algorithm results of TMH had a higher correlation (r = 0.965, p < 0.001) with the ground-truth compared with the manual obtained results (r = 0.898, p < 0.001). The curve of TMH was plotted to reveal the spatial variation along the lower eyelid from nasal and temporal. Higher TMH were found at nasal (median: 0.26 mm) and temporal (0.27 mm) canthi compared with the locations right under the pupil center (0.19 mm). On the experimental data, the proposed method provided reliable TMH results with a higher consistency and efficacy. It was expected to form an assistive tool in TMH quantitation and subsequently and screening on Dry Eyes Disease.
Purpose
The aim of our research was to investigate the reliability and clinical applicability of a modern tear film imaging tool by comparing the inter- and intragrader difference. The further goal ...was to compare the non-invasive tear break-up time (NIBUT) measured with the LacryDiag® device with traditional tear film break-up time (TBUT).
Methods
Comprehensive ophthalmological examination was performed, including LacryDiag® (Quantel Medical, France) (lower tear meniscus height measuring (LTMH), superior and inferior eyelid meibography (MeibS MeibI), interferometry (INT), NIBUT), slit lamp examination, and TBUT. Two independent, well-trained graders selected and analyzed the LTMH, MeibI, MeibS, and INT. The second grader reanalyzed the data 1 month later. Intra- and inter-examiner reliabilities were evaluated using intraclass correlation coefficients (ICC), while for categorical variable, Cohen’s kappa statistics were provided. The Bland-Altman plot was used for visualization of the agreement between measurements.
Results
Fifty healthy volunteers were examined. For LTMH both the inter- and intragrader variabilities were excellent. Between two graders, the ICC of MeibI was poor; however, between two graders, the ICC of MeibS was good, and the intragrader variability in MeibI and MeibS was excellent. For the INT, both intra- and intergrading were in fair and moderate agreement, although the intragrader agreement was higher. Comparing the NIBUT and TBUT, the agreement was slight.
Conclusion
Based on our results, examination of a patient during follow-up should be performed by the same examiner, because of the slight agreement. The LacryDiag® is a non-invasive, easy-to-use device, which can examine the tear film and save the recordings for easier follow-up.
To compare the effect of single-drop administration of two different ophthalmic solutions on tear meniscus and tear osmolarity in patients with mild to moderate dry eye disease.
This prospective ...study comprised of 122 patients with mild to moderate dry eye disease. These patients received a single dose of either unpreserved trehalose 3%, hyaluronic acid 0.15%, carbomer 0.25% (THHA, Thealoz Duo Gel) (Group 1) or hyaluronic acid 0.3% (HA) (Group 2) gel-based lubricants. Tear meniscus (height and depth) were measured using anterior segment optic coherence tomography (AS−OCT) at baseline and 10, 60, 120, and 240 min. after instillation. Tear osmolarity, Schirmer I test, tear break-up time (TBUT), gel properties, and patient comfort were evaluated 240 min. after instillation.
Tear meniscus height (TMH) and tear meniscus depth (TMD) showed a significant increase with both lubricants compared to the baseline (p < 0.001). This effect remained significant for up to 60 min. and 120 min. for the THHA and HA 0.3% solutions, respectively (p < 0.05, for both). Mean comfort duration was 115.1 ± 20.1 min. in Group 1 and 148.3 ± 49.0 min in Group 2 (p < 0.001). Tear osmolarity, Schirmer I test, and TBUT were similar between the baseline and 240 min. for each group.
The results of this study demonstrate that 0.3% HA remains on the ocular surface for longer than TH-HA. The longer ocular residency time also seems to correlate with a longer patient comfort duration.
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