Development of a new grading scale for tear ferning

The final publication is available at Elsevier via https://dx.doi.org/10.1016/j.clae.2013.09.011" © 2014. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/Purpose: This paper reports on the development of a new tear ferning (TF) subjective grading scale, and compares it with the Rolando scale. Method: TF patterns obtained from tear film samples collected from normal and dry eye subjects in previous studies were collated into a large image library. From this library, 60 images were selected to represent the full range of possible TF patterns, and a further sub-set of 15 images was chosen for analysis. Twenty-five optometrists were asked to rank the images in increasing order between extreme anchors on a scale of TF patterns. Interim statistical analysis of this ranking found 7 homogeneous sub-sets, where the image rankings overlapped for a group of images. A representative image (typically the mean) from each group was then adopted as the grade standard. Using this new 7-point grading scale, 25 optometrists were asked to grade the entire 60 image library at two sessions: once using the 4-point Rolando scale and once using the new 7-point scale, applying 0.25 grade unit interpolation. Results: Statistical analysis found that for the larger image set, the Rolando scale produced 3 homogeneous sub-sets, and the 7-point scale produced 5 homogeneous sub-sets. With this refinement, a new 5-point TF scale (Grades 0–4) was obtained. Conclusions: The Rolando grading scale lacks discrimination between its Type I and II grades, reducing its reliability. The new 5-point grading scale is able to differentiate between TF patterns, and may provide additional support for the use of TF for both researcher and clinician

The tear ferning test: a simple clinical technique to evaluate the ocular tear film

This is the peer reviewed version of the following article: Masmali, A. M., Purslow, C., & Murphy, P. J. (2014). The tear ferning test: a simple clinical technique to evaluate the ocular tear film: The tear ferning test. Clinical and Experimental Optometry, 97(5), 399–406., which has been published in final form at https://doi.org/10.1111/cxo.12160. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.A healthy tear film is very important for many major functions of the ocular surface. Dry eye disease is a significant clinical problem that needs to be solved but the poor correlation between clinical signs and reported symptoms makes it difficult for the clinician to apply a scientific basis to his clinical management. The problem is compounded by the difficulties of evaluating the tear film due to its transparency, small volume and complex composition. Practical insight into tear film composition would be very useful to the clinician for patient diagnosis and treatment but detailed analysis is restricted to expensive, laboratory-based systems. There is a pressing need for a simple test. The tear ferning test is a laboratory test but it has the potential to be applied in the clinic setting to investigate the tear film in a simple way. Drying a small sample of tear fluid onto a clean, glass microscope slide produces a characteristic crystallisation pattern, described as a ‘tear fern’. This test is currently not widely used because of some limitations that need to be overcome but several studies have demonstrated its potential. Such limitations need to be resolved so that tear ferning could be used in the clinic setting to assess the tear film

A computer-based image analysis for tear ferning featuring

The present work focuses on the development of a novel computer-based approach for tear ferning (TF) featuring. The original TF images of the recently developed five-point grading scale have been used to assign a grade for any TF image automatically. A vector characteristic (VC) representing each grade was built using the reference images. A weighted combination between features selected from textures analysis using gray level co-occurrence matrix (GLCM), power spectrum (PS) analysis and linear specificity of the image were used to build the VC of each grade. A total of 14 features from texture analysis were used. PS at different frequency points and number of line segments in each image were also used. Five features from GLCM have shown significant differences between the recently developed grading scale images which are: angular second moment at 0° and 45°, contrast, and correlation at 0° and 45° these five features were all included in the characteristic vector. Three specific power frequencies were used in the VC because of the discrimination power. Number of line segments was also chosen because of dissimilarities between images. A VC for each grade of TF reference images was constructed and was found to be significantly different from each other's. This is a basic and fundamental step toward an automatic grading for computer-based diagnosis for dry eye

Application of a new grading scale for tear ferning in non-dry eye and dry eye subjects

The final publication is available at Elsevier via http://dx.doi.org/10.1016/j.clae.2014.09.007 © 2014. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/Purpose: To apply the Masmali tear ferning (TF) grading scale on non-dry eye (NDE) and dry eye (DE) subjects to test the validity of the grading scale in practice, and to describe the grading scale range for NDE and DE. Method: Forty NDE subjects (20 males, 20 females) and 40 DE subjects (23 males, 17 females) ranging in age from 19 to 53 years (mean ± SD: 25.3 ± 5.5) with no other ocular disease, no contact lens wear, and not pregnant or breastfeeding were recruited. McMonnies scores were used for subject grouping. Phenol red thread (PRT) and slit-lamp test were used. A tear sample was collected from right eye, which was then dried to produce a ferning pattern, that was observed using a digital microscope, and graded. Results: Mean McMonnies, PRT and TF grade in NDE subjects were 7.1 ± 3.8, 27.4 ± 4.3 mm and 0.78 ± 0.40, respectively. Median McMonnies, PRT and TF grade in DE subjects were 16.5 ± 3.0, 9.0 ± 2.0 mm and 2.3 ± 1.48, respectively. In NDE subjects, grades 0.0–1.8 were observed (82.5% Grade 0.0–1.00). Grades 2.0–4.0 were observed in DE subjects (72.5% Grades 2.0–3.0). For all subjects, there were large correlations between TF grade and PRT (r = −0.79), PRT and McMonnies (r = −0.60), and TF and McMonnies (r = 0.73). Conclusions: The Masmali TF grading scale showed good validity in describing the TF patterns. Grades ≥2 can be classified as abnormal patterns. The TF test has the potential to be used in the clinic

Repeatability and Diurnal Variation of Tear Ferning Test

This is a non-final version of an article published in final form in: Masmali, A. M., Al-Bahlal, J. M., El-Hiti, G. A., Akhtar, S., Purslow, C., Murphy, P. J., & Almubrad, T. (2015). Repeatability and Diurnal Variation of Tear Ferning Test: Eye & Contact Lens: Science & Clinical Practice, 41(5), 262–267. https://doi.org/10.1097/ICL.0000000000000116Objectives: To investigate tear ferning (TF) test repeatability between sessions by observing changes in the tear fern pattern during the day. Methods: Twenty-three healthy young adults (15 men and 8 women), ranging in age from 20 to 32 years (mean±SD: 22.9±3.3 years) without signs or symptoms of dry eye disease, ocular disease, or contact lens wear were enrolled in the study. Schirmer I, tear break-up time (TBUT) test, and McMonnies questionnaire were used to screen volunteers. Schirmer I and TBUT tests were applied to both eyes in each subject. Four samples of tear fluid were collected from the right eye of each subject using glass capillaries at set intervals during a single day (9 AM, 11 AM, 2 PM, and 4 PM). The TF patterns obtained from samples were classified according to the Masmali TF grading scale to increments of 0.1. Results: The median values obtained from the McMonnies, Schirmer, and TBUT tests were 4.0±2.0, 30.0±7.0 mm (OD), and 16.0±10.0 sec (OD), respectively. There were no statistically significant differences between the TF grades for tear samples collected at different times of the day (Wilks' Lambda, P=0.351). The majority (84.8%) of TF grades was between 0.0 and 1.5; the remaining 15.2% of subjects had TF between grades 1.6 and 1.9. The overall mean grade for the TF was 1.1±0.3. There were small insignificant correlations between TF grades and the McMonnies questionnaire (r=0.1.30) and TBUT (r=0.248) and a negligible correlation with Schirmer test (r=−0.046). Conclusions: The results found no significant differences within the TF for tear samples collected at different times of the day, suggesting that there is little diurnal variation evident.The authors extend their appreciation to the College of Applied Medical Sciences Research Center and the Deanship of Scientific Research at King Saud University for its funding of this research

Crystal structure of 3-tert-butyl-7-azadioxindole, C11H14N2O2

C11H14N2O2, orthorhombic, P212121 (no. 19), a = 7.3227(3) Å, b = 10.9955(4) Å, c = 26.3709(9) Å, V = 2123.30(14) Å3, Z = 8, Rgt(F) = 0.0372, wRref(F2) = 0.0907, T = 150 K

Analysis of basal and reflex human tear osmolarity in normal subjects: assessment of tear osmolarity

Purpose: The aim of this study is to evaluate the difference between reflex and basal tear osmolarity among healthy normal subjects. Method: The right eyes of 20 healthy normal male subjects aged 20 to 40 years were recruited for this study. The inclusion criteria for the subjects were the Ocular Surface Disease Index questionnaire score of less than 12 and wetting length of the phenol red thread of more than 10 mm. Tear film osmolarity was assessed using TearLab osmometer. Basic tear osmolarity was measured normally without inducing any irritation to the eye. In order to stimulate reflex tear, subjects were asked to open their eye as long as they can till they feel ocular surface irritation (minimum 20 s). Results: The mean score on the Ocular Surface Disease Index questionnaire was 5.5 ± 3. The mean value obtained from the phenol red thread was 21 ± 4.5 mm. There were no statistically significant differences between the osmolarity readings of basal and reflex tear osmolarity ( p > 0.05). The mean value was 308 ± 12 and 306 ± 9 mOsm/l for basic and reflex tear osmolarity, respectively. Conclusion: This study found that the osmolarity of the basal and reflex tears fell within the same range. The values found in this study are in agreement with published results for normal subjects

Crystal structure of 2-tert-butyl-1,3-thia- zolo[4,5-b]pyridine

The title compound, C 10 H 12 N 2 S, does not contain any strong hydrogen-bond donors but two long C-HÁ Á ÁN contacts are observed in the crystal structure, with the most linear interaction linking molecules along [010]. The ellipsoids of the tert-butyl group indicate large librational motion

(E)-3-(4-Bromo-5-methylthiophen-2-yl)acrylonitrile

In the title structure, C8H6BrNS, the molecules are planar with the exception of the methyl H atoms. In the crystal, molecules are linked by intermolecular C—H...N interactions to form ribbons parallel to the b axis. Groups of ribbons are arranged in a herringbone pattern to form a layered structure parallel to the ab plane