Tiled views of confocal reflection and fluorescence of the normal mouse BM. Confocal reflection 3D image (A) displays the bone structure (white): the outer shell as well as several internal bone spikes and trabecullae can be identified (using a 633-nm laser light reflected on the imaging detector). In the corresponding confocal fluorescence 3D image (B), cells (DAPI, blue) and vascular structures and extracellular matrix (collagen type IV, green) are shown; several tissue discontinuities appear like “holes.” The merged image (C) clearly demonstrates the overlap of the bone structures over these discontinuities. Tiled z-stacks of images were collected over large volume (2.6 × 1.2 mm × 150 μm) of the mouse BM tissue and computationally stitched. A large tile over entire bone fossae is depicted in panels (D) (bone reflection) and E (merged with the fluorescence of CD34 in red, collagen type IV in green, DAPI in blue) respectively, to illustrate very good tissue preservation. Related images appear in supplemental Video 3).