Topographic and specular microscopic evaluation of cornea and meibomian gland morphology in children with isolated growth hormone deficiency.

PURPOSE: To evaluate whether the anterior segment topographic measurements, meibomian gland (MG), and non-invasive tear film break-up time (NITFBUT) differ between healthy children and children with isolated growth hormone deficiency (GHD). METHODS: A total of 74 eyes of 37 children with GHD and 84 eyes of 42 age- and sex-matched healthy children were included in the study. The spherical equivalence (SE), mean keratometry (Km), corneal thickness, corneal volume (CV), anterior chamber depth (ACD), topographic NITFBUT, qualitative and quantitative MG measurements, corneal endothelial cell density (CD), and proportion of hexagonal cells (HG) were analysed. RESULTS: The mean SE level of GHD group was similar between groups (p = 0.017). Back Km values were insignificantly steep in children with GHD (p = 0.004, with Bonferroni correction). Specular microscopy analysis was not different between groups. MG loss of GHD group were higher than control group (p < 0.001). The MG morphology analysis and distortion grade were not different between groups (p > 0.05). CONCLUSIONS: Our results showed that the growth hormone (GH) may have an important role on the anterior segment parameters; however, it is not clear that this misregulation leads to a clinical scenario in childhood. Future studies investigating GHD and/or GH therapy on the ocular surface system are required to clearly demonstrate basic mechanism of GH action.

Repeatability of non-invasive break-up time measures with a new automated dry eye platform in healthy eyes.

PURPOSE: To evaluate the intrasession repeatability for non-invasive break-up time (NIBUT) and tear meniscus height (TMH) measurements provided by a new multi-diagnostic platform, and to assess the interobserver reproducibility of TMH measures. METHODS: Twenty-one healthy eyes of 21 patients (age, 23-65 years) were enrolled. A complete eye examination was performed in all cases with the VX120+ device (Visionix-Luneau Technologies), including an analysis with the new Dry Eye module, performing three consecutive measurements. The within-subject standard deviation (Sw) and Bland-Altman plots were used to assess intersession repeatability. Differences between examiners for TMH were also analysed. RESULTS: No statistically significant differences were found between repeated measures of NIBUT (time associated with the first break) and TMH (p > 0.05). However, significant differences were found for NIBUT50% (time associated with half of breaks of the tear film) (p < 0.05). Mean Sw was 0.9 s, 1.4 s and 0.05 mm for NIBUT, NIBUT50% and TMH, respectively. Ranges of agreement between consecutive measures were below 3.5 s and 4.5 s for NIBUT and NIBUT50%, respectively, and below 0.16 mm for TMH. Furthermore, no significant differences were found between examiners in TMH measure, with an inter-examiner range of agreement of 0.12 mm. CONCLUSIONS: The new dry eye platform of the VX120+ platform evaluated provides objective automated measures of NIBUT and TMH, with acceptable level of intrasession repeatability for clinical screening purposes.

Tear film measurements in four different ethnic groups: Malay, Chinese, Indian and Nigerian / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To compare the non-invasive tear film break-up time(NIBUT), tear break up time(TBUT), basal tear secretion(BTS)and blink rate in four ethnic groups: Malay, Chinese, Indian and Nigerian.<p>METHODS: Totally 120 healthy(61 males and 59 females)subjects(without dry eye symptoms and ocular surface disorder)with the age 20 to 39 years were recruited; 30 were Malays, 30 were Chinese, 31 were Indians and 29 were Nigerians. Based on McMonnies questionnaire and clinical examination, normal subjects were selected. NIBUT, TBUT, BTS were assessed in only one eye(right)of each subject and blink rate was also assessed.<p>RESULTS: There was significant difference in the NIBUT, TBUT, BTS and blink rate among 4 different ethnic groups(<i>P</i>=0.018),(<i>P</i>=0.001),(<i>P</i>=0.011), and(<i>P</i>=0.004)respectively. No statistically significant difference of NIBUT, TBUT, BTS and blink rate was found between the genders among different ethnic groups. Indian had higher median for NIBUT(10±6s), TBUT(7±5s)and BTS(20±20 mm)than others races. Chinese had lower median for NIBUT(7.5±4s)and TBUT(4±2s)while Malay had low BTS(9.5±16 mm)among the groups. There was no significant correlation of blink rate with NIBUT, TBUT and BTS(<i>r</i>= -0.119, <i>P</i>=0.195),(<i>r</i>=-0.086, <i>P</i>=0.352),(<i>r</i>= -0.123, <i>P</i>=0.180)respectively.<p>CONCLUSION: This study showed the variability in tear-film measurements values in four ethnic groups.

Noninvasive evaluation of anterior segment and tear film parameters and morphology of meibomian glands in a pediatric population with hypogonadism.

PURPOSE: To compare the meibomian gland (MG), non-invasive tear film break-up time (NITFBUT), anterior segment measurements between healthy children and children with hypogonadism. METHODS: A total of 80 eyes of 40 children with hypogonadism and 86 eyes of 43 age- and sex-matched healthy subjects were included in the study. The mean keratometry (Km), maximum keratometry (Kmax), central (CCT), thinnest (TCT) and apical (ACT) corneal thicknesses, corneal volume (CV), anterior chamber depth (ACD), irido-corneal angle (ICA), first and average non-invasive NITFBUT, MG loss, morphology of MGs, and MG distortion grade, specular endothelial cell density (CD), coefficient of variation (CoV), and percentage of hexagonal cells (HG) were analysed. RESULTS: The mean CCT and TCT values were approximately 20 µm lower on average in patients with hypogonadism (p < 0.05). MG loss was present 56.1% of the healthy children, the ratio increased to 81.3% in children with hypogonadism (p < 0.001). The morphology and distortion grade did not show any significant differences between groups (p > 0.05). The mean NITFBUT value were similar between groups (p > 0.05). The mean CD value did not show any significant difference between groups, however it decreased in the hormone replacement therapy (HRT) group (p = 0.005). CONCLUSIONS: MG loss is a physiological process that is prominent in the condition of sex steroid deficiency, but does not cause tear film alterations in children. Future studies investigating sex and gender effect on the ocular surface system in an age-based fashion are required to clearly communicate influences in the arenas of ocular surface research.

Dry eye features of keratoconus at different stages using Keratograph and its clinical values / 眼科新进展

Objective To compare the dry-eye features of normal cornea and keratoconus at different stages using non-invasive dry-eye integrated analyzer (Keratograph) and it clinical significance.Methods A case-control study was conducted in 35 patients (44 eyes) with keratoconus who were treated in our hospital from May 2015 to December 2016 as keratoconus group and 45 patients (45 eyes) who received laser corneal refractive surgery as normal cornea group;and subjects in the keratoconus group were subgrouped into mild group (19 eyes),moderate group (15 eyes) and severe group (10 eyes) according to Amsler-Krumeich grading method.The first tear break-up time (first BUT),mean BUT,tear meniscus height (TMH) and conjunctival hyperemia scoring (CHS) of the both eyes in all groups were measured by Keratograph,and the diagnostic values of these variables for keratoconus at different stages were analyzed by ROC curve.Results The levels of horizontal central curvature,vertical center curvature,surface variation index,keratoconus index,posterior corneal surface height and CHS of the keratoconus group were higher than those of the normal cornea,and the difference were statistically significant (all P ＜ 0.05).The non-invasive first BUT,mean BUT and TMH in the keratoconus group were significantly lower than those of the normal cornea group,approaching significant difference (all P ＜ 0.05).The differences in horizontal central curvature,vertical center curvature,surface variation index,keratoconus index,posterior corneal surface height,first BUT and mean BUT among subgroups of keratoconus patients had statistically significance (all P ＜ 0.05).The first BUT and mean BUT in the moderate and severe group were lower than those in the mild group,the difference was statistically significant (all P ＜ 0.05),but there was no significant difference between the moderate and severe group (all P ＞ 0.05).In addition,the mean BUT was negatively correlated with horizontal central curvature,vertical center curvature,surface variation index,keratoconus index and posterior corneal surface height,but had no significant correlation with TMH and CHS (all P ＞ 0.05).ROC curve analysis showed that keratoconus index had the highest diagnostic value for keratoconus than other variables (AUC =0.790,95％ CI:0.689-0.892;P ＜ 0.001).Conclusion The Keratograph dry-eye analyzer can effectively measure the dry-eye parameters of the cornea and the mean BUT in the measurement parameters is the most valuable for the diagnosis of keratoconus,and it is more meaningful for the diagnosis of mild keratoconus.

Reliability of a New Non-invasive Tear Film Break-up Time Measurement Using a Keratograph

PURPOSE: To evaluate the repeatability of non-invasive tear film break-up time and identify its relationships with dry eye parameters. METHODS: A total of 100 participants (50 with dry eye, and 50 in the control group) were enrolled prospectively. Non-invasive keratograph first (NIKf-BUT) and average (NIKav-BUT) break-up times were evaluated 2 times using Keratograph 4 (Oculus, Wetzler, Germany), and then tear film break-up time with fluorescein (FBUT) was measured. The correlation analyses were performed between non-invasive parameters (NIKf-BUT and NIKav-BUT) and FBUT. Intra-observer agreements of NIKf-BUT and NIKav-BUT were assessed using intraclass correlation coefficients (ICC). The receiver operating characteristic (ROC) curve technique was used to evaluate the non-invasive method in the diagnosis of dry eye. RESULTS: The correlation analyses revealed positive correlation between NIKav-BUT and FBUT in both groups (dry eye; r = 0.66, p < 0.001 and control group; r = 0.77, p < 0.001). The ICCs of NIKf-BUT and NIKav-BUT were 0.72 and 0.94 in the dry eye, respectively, and 0.70 and 0.91 in the control group. NIKav-BUT was not different from FBUT in either group. The areas under the ROC curves of NIKf-BUT and NIKav-BUT were 0.917 and 0.980, respectively. CONCLUSIONS: The high ICCs verified the repeatability of NIKf-BUT and NIKav-BUT. NIKav-BUT showed no difference from FBUT and positive correlation with FBUT. NIK-BUT showed high diagnostic power and can be considered a new parameter to evaluate dry eye syndrome.