Confocal microscopy and stereology: Estimating volume, number, surface area and length by virtual test probes applied to three-dimensional images

The opportunities of confocal microscopy applied to morphometry of microsco pical structures are presented and demonstrated on stereological methods ba sed on evaluation of optical sections within a thick slice and using comput er-generated virtual test probes. Such methods, allowing arbitrary orientat ion of the thick slice, can be used for estimating volume, number, surface area, and length. The methods using spatial grid of points, disector, fakir , and slicer probes are described and illustrated by different examples usi ng our freeware 3DTOOLS software and their variance and applicability are d iscussed. It is shown that shifted triple or quadruple spatial grids of lin es are very efficient for the surface area and volume estimation by the fak ir method. Microsc. Res. Tech. 53:425-435, 2001. (C) 2001 Wiley-Liss, Inc.