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The compromise between lateral resolution and usable imaging depth range is a bottleneck for optical coherence tomography (OCT). Existing solutions for optical coherence microscopy (OCM) suffer from either large data size and long acquisition time or a nonideal point spread function. We present volumetric OCM of mouse brain ex vivo with a large depth coverage by leveraging computational adaptive optics (CAO) to significantly reduce the number of OCM volumes that need to be acquired with a Gaussian beam focused at different depths. We demonstrate volumetric reconstruction of ex-vivo mouse brain with lateral resolution of 2.2  μm, axial resolution of 4.7  μm, and depth range of ∼1.2  mm optical path length, using only 11 OCT data volumes acquired on a spectral-domain OCM system. Compared to focus scanning with step size equal to the Rayleigh length of the beam, this is a factor of 4 fewer datasets required for volumetric imaging. Coregistered two-photon microscopy confirmed that CAO-OCM reconstructions can visualize various tissue microstructures in the brain. Our results also highlight the limitations of CAO in highly scattering media, particularly when attempting to reconstruct far from the focal plane or when imaging deep within the sample.

Three-dimensional optical coherence tomography (3D-OCT) is used to evaluate the structure and pathology of regenerating mouse skeletal muscle autografts for the first time. The death of myofibers with associated inflammation and subsequent new muscle formation in this graft model represents key features of necrosis and inflammation in the human disease Duchenne muscular dystrophy. We perform 3D-OCT imaging of excised autografts and compare OCT images with coregistered histology. The OCT images readily distinguish the necrotic and inflammatory tissue of the graft from the intact healthy muscle fibers in the underlying host tissue. These preliminary findings suggest that, with further development, 3D-OCT could be used as a tool for the evaluation of small-animal muscle morphology and pathology, in particular, for analysis of mouse models of muscular dystrophy.