Multiple count sampling of goblet cells in microscope high-power fields using conjunctival impression cytology

Area of Science:

• Ocular surface disease research
• Cell biology and histology

Background:

• Conjunctival impression cytology for goblet cell density assessment yields inconsistent results.
• The sources of this variability in goblet cell counts are not well understood.
• Systematic analysis is needed to identify and mitigate variability in goblet cell density measurements.

Purpose of the Study:

• To investigate the sources of variability in goblet cell density assessments using conjunctival impression cytology.
• To determine the optimal number of high-power fields for reliable goblet cell counting.
• To provide recommendations for improving the consistency of goblet cell density measurements.

Main Methods:

• Conjunctival impression cytology specimens were collected from 20 healthy adults.
• Filter units were applied to the superior bulbar conjunctiva.
• Goblet cells were counted in 10 random, non-overlapping high-power fields per specimen using Giemsa staining.

Main Results:

• Goblet cell counts varied widely (0-74 cells/high-power field), with a mean of 11.6 ± 14.8.
• Averaging counts across multiple fields progressively decreased the mean goblet cell number.
• Relative variability (coefficient of variation) remained high, exceeding 100% even with increased counts.

Conclusions:

• Multiple goblet cell counts per specimen enhance measurement reliability.
• Utilizing more than five to seven high-power fields does not significantly improve the precision of goblet cell density assessment.
• Standardized counting protocols are essential for consistent goblet cell density evaluation.