TABLE 2.

KERATOCYTE DENSITY AND NUMBER OF KERATOCYTES IN NORMAL CORNEAS, CLEAR GRAFTS, AND GRAFTS WITH LATE ENDOTHELIAL FAILURE (MEAN ± STANDARD DEVIATION)

	NORMAL (UNOPERATED) CORNEAS (n=63)	CLEAR PENETRATING GRAFTS (n=99)	LATE ENDOTHELIAL FAILURE (n=12) (MDD)*
Full-thickness keratocyte density (cells/mm3, weighted mean)	26,610 ± 3,683	22,101 ± 3,799†	21,268 ± 3,298† [3,250]
KERATOCYTE DENSITY BY PERCENT DEPTH OF STROMA (CELLS/MM3)
Anterior 0–10%	42,513 ± 8544	33,598 ± 7,967†	34,586 ± 7,791‡ [6,900]
11%–33%	28,093 ± 4,918	24,855 ± 5,289†	26,170 ± 5,883§ [4,650]
34%–66%	23,614 ± 4,744	21,441 ± 5,129‡	19,215 ± 5,618‡ [4,500]
67%–90%	23,943 ± 4,561	17,281 ± 5,580†	15,372 ± 4,187† [4,750]
Posterior 91%–100%	24,141 ± 4,704	17,654 ± 6,089†	17,985 ± 6,966† [5,350]
No. of keratocytes in full- thickness central stroma with frontal area of 1 mm2 (cells)	11,466 ± 1,503	10,325 ± 1,708†	10,778 ± 1,760§ [1,490]

^*MDD, minimum detectable difference between clear grafts and grafts with late endothelial failure because no significant differences existed for any variable (α = 0.05, β = 0.20).

^†P< .001 vs normal (unpaired t tests).

^‡P< .01 vs normal (unpaired t tests).

^§P> .05 vs normal (unpaired t tests). The minimum detectable difference for keratocyte density in the 11%–33% region of stroma was 4,550 cells/mm², and for the number of keratocytes was 1,400 cells (α = 0.05, β = 0.20 for both analyses).