Table 1.

Cell Densities in Five Layers of 15 Normal Corneas Determined by Automatic and Manual Methods in the Same ConfoScan 4 Images

Stromal Layer	Automatic	Manual	Difference
Anterior 10%	31,644 ± 5,279	32,062 ± 5,230	−418 ± 4,309
10%–33%	26,021 ± 2,506	25,289 ± 3,564	732 ± 2,840
33%–66%	24,164 ± 4,177	24,400 ± 3,506	−236 ± 2,546
66%–90%	24,687 ± 4,489	24,766 ± 3,419	−79 ± 3,336
90%–100%	24,504 ± 4,594	25,054 ± 3,071	−549 ± 3,852
Unweighted mean n = 75 layers	26,204 ± 5,046	26,314 ± 4,729	−110 ± 3,374

Cell density is expressed as mean cells per cubic millimeter ± SD. These densities were used to determine selection parameters for the cell-counting program. Differences between the automatic and manual methods were not significant (P > 0.3).