On the Use of NIH Image J for Objective Assessment of Conjunctival Cell and Nucleus Dimensions of Impression Cytology Samples

Experimental Research into the Uniaxial Compressive Strength of Low-Density Reef Limestone Based on Image Recognition

Low-density reef limestone is widely distributed in tropical oceans; exploring its mechanical properties is of significance to practices in marine foundation engineering. In this research, laboratory experiments on low-density reef limestones with two different types of porous structures were conducted using image recognition methods to study the special mechanical properties of low-reef limestone. S¯ was defined as the parameter quantifying the pore geometry, and the calculation method of S¯ was optimized based on image recognition data. Finally, the influencing factors of uniaxial compressive strength (UCS) of low-density reef limestone were analyzed, and a modified formula considering pore structure was proposed. The results indicate the following: Image recognition methods were used to determine feasibility and convenience of capturing 2D pore geometric information of specimens. The optimization method of S¯ is conducive to improving automatic image recognition accuracy. Low-density reef limestones with different porous structures show small difference in porosity and density, while they exhibit large differences in pore sizes and UCS. The UCS of low-density reef limestone is found to be jointly influenced by pore structure and density (it increases with the decrease in parameter S¯ and increase in density). The results may provide help for those investigating the mechanical properties of reef limestone and practices in marine foundation engineering.

Assessment of goblet cell size and density in relation to epithelial cell (multi)layering on conjunctival impression cytology samples

PURPOSE

To assess goblet cell size and numbers in relation to the extent of multilayering of conjunctival impression cytology (CIC) samples as a basis for reducing variability in image selection for goblet cell density (GCD) estimates.

METHODS

CIC was undertaken immediately postmortem off the superior bulbar conjunctiva of healthy young adult rabbits onto Millicell-CM Biopore filter units. After fixation with buffered glutaraldehyde and Giemsa staining, two × 200 images were selected from each sample representative of either slight multilayering or substantial multilayering, projected at × 1000, an overlay of the outlines of the goblet cells was made, and their dimensions and areas were measured.

RESULTS

From measures of 4918 goblet cells, the average value (+/- SD) for the longest dimension was 17.7 ± 6.4 μm and 14.6 ± 5.3 μm for the shortest dimension. The GCD values ranged from 210 to 2069/mm², with a mean of 1074 ± 601/mm², but was lower for slightly multilayered images (at 537 ± 239 cells/mm ) compared with multilayered regions (at 1612 ± 601 cells/mm²; p < 0.001). The measured areas ranged from 72 to 491 μm², with average values from any particular image ranging from 110 to 370 μm², which were inversely correlated with the estimated GCD (Spearman's rho = - 0.722, p < 0.05).

CONCLUSIONS

Larger goblet cells but in fewer numbers were predictably found across the filter surface where there were fewer layers of cells and vice versa. This difference could be considered in selection of images for counts of goblet cells from CIC specimens.

Assessment of Consistency in Assignment of Severe (Grade 3) Squamous Metaplasia to Human Bulbar Conjunctiva Impression Cytology Cell Samples

Nucleus-to-cytoplasm (N:C) characteristics of published images of human bulbar conjunctival cells designated as showing severe (grade 3) squamous metaplasia were retrospectively assessed. From publications over a 40-year period, measurements were made from images of cell and nucleus size (based on areas and dimensions) and four different calculations were made for nucleo-cytoplasmic (N:C) ratios. From 54 published images, the mean nucleus-to-cytoplasm area ratio (NU/CYT AREA ratio) was 0.145 +/- 0.077 (range 0.052 to 0.346), compared to two different reference set values of 0.069 +/- 0.017 and 0.080 +/- 0.021. Similarly, a nucleus-to-cytoplasm length ratio (as LNLONG) was 0.308 +/- 0.080 (range 0.191 to 0.475) compared to reference values of 0.226 +/- 0.032 and 0.236 +/- 0.034. Similar differences in reference values were obtained using two other N:C ratio calculations. A wide range of values was found for morphometric N:C indices from published images, especially those without a scale bar, indicating a high incidence of inconsistent grading assignments. Overall, only about 30% of the published images showed morphological features consistent with severe squamous metaplasia (i.e., with the rest neither enlarged nor showing substantially changed N:C ratios) with no substantial pictorial evidence indicating that cells from the human bulbar conjunctiva have pyknotic nuclei. Current evidence indicates that grade 3 squamous metaplasia cells should be substantially enlarged.

Contact lens wear and the goblet cells of the human conjunctiva-A review

PURPOSE

To review the reported effects of contact lens wear on the goblet cells of the human conjunctiva.

METHODS

A literature search was undertaken to identify reports on the conjunctival health after contact lens wear, principally as assessed using the conjunctival impression cytology (CIC) technique in which cells are examined ex vivo, after fixation and staining. Details of technique, data on duration of contact lens wear and then CIC outcome in terms of goblet cell density (GCD) were extracted.

RESULTS

Of 24 reports identified, 22 examined the bulbar conjunctiva and 2 examined the tarsal conjunctiva. A decrease in GCD was considered, directly or indirectly, to be a consequence of contact lens wear in 18 of the studies, but there was no obvious overall relationship between duration of lens wear and the GCD changes. Conversely, four reports indicated an increase in GCD or goblet cell-related mucins. Two reports concluded that there was no change in goblet cells or their mucin, a result however that is consistent with a recent conclusion that no statistically significant change in GCD was detectable in contact lens wearers assessed by in vivo imaging of the human conjunctiva by confocal microscopy.

CONCLUSIONS

The majority of published studies have concluded that contact lens wear results in a decrease in goblet cells in the conjunctiva. While there are reports that draw a very different conclusion, it should be noted that there has been limited consistency in technique or the method of reporting the results across the various studies.