A computer-implemented method (300, 500, 600) of correcting motion from medical images by processing medical image data (200A - 200C), the method comprising: receiving (302, 502, 602) a first set of data (906, 914) from an imaging acquisition session representing a first three-dimensional medical image produced by a medical imaging instrument; receiving (304, 502, 602) a second set of data (908, 916) from the imaging acquisition session representing a second three-dimensional medical image produced by the medical imaging instrument; generating (306, 502, 602) a first two-dimensional medical image by projecting the first set of data (906, 914) onto a first plane; generating (308, 502, 602) a second two-dimensional medical image by projecting the second set of data (908, 916) onto the first plane; calculating (310, 502, 602) a spatial registration that exists between the first two-dimensional medical image and the second two-dimensional medical image in the first plane; generating (312, 516, 602) a correction vector based on the spatial registration; modifying (314, 518, 602) the second set of data by applying the correction vector to one or more of the datum in the second set of data; generating (316, 518, 624) a combined set of data (922, 918) representing a processed three-dimensional medical image by combining the first set of data and the modified second set of data; receiving (304, 502, 602) a third set of data from the imaging acquisition session representing a third three-dimensional medical image produced by the medical imaging instrument; generating (308, 502, 602) a third two-dimensional medical image (400A - 400D, T z, T y, T x, 902) by projecting the third set of data onto the first plane; generating (306, 502, 602) a fourth two-dimensional medical image (400A - 400C, T z, T y, T x) by projecting the combined set of data onto the first plane; calculating (310, 502, 602) a second spatial registration that exists between the third two-dimensional medical image and the fourth two-dimensional medical image in the first plane; generating (312, 516, 602) a second correction vector based on the second spatial registration; modifying (314, 518, 602) the combined set of data by applying the second correction vector to one or more of the datum in the combined set of data; and generating (316, 518, 624) a second combined set of data representing a second processed three-dimensional medical image by combining the third set of data and the modified combined set of data. receiving (302, 502, 602) a first set of data (906, 914) from an imaging acquisition session representing a first three-dimensional medical image produced by a medical imaging instrument; receiving (304, 502, 602) a second set of data (908, 916) from the imaging acquisition session representing a second three-dimensional medical image produced by the medical imaging instrument; generating (306, 502, 602) a first two-dimensional medical image by projecting the first set of data (906, 914) onto a first plane; generating (308, 502, 602) a second two-dimensional medical image by projecting the second set of data (908, 916) onto the first plane; calculating (310, 502, 602) a spatial registration that exists between the first two-dimensional medical image and the second two-dimensional medical image in the first plane; generating (312, 516, 602) a correction vector based on the spatial registration; modifying (314, 518, 602) the second set of data by applying the correction vector to one or more of the datum in the second set of data; generating (316, 518, 624) a combined set of data (922, 918) representing a processed three-dimensional medical image by combining the first set of data and the modified second set of data; receiving (304, 502, 602) a third set of data from the imaging acquisition session representing a third three-dimensional medical image produced by the medical imaging instrument; generating (308, 502, 602) a third two-dimensional medical image (400A - 400D, T z, T y, T x, 902) by projecting the third set of data onto the first plane; generating (306, 502, 602) a fourth two-dimensional medical image (400A - 400C, T z, T y, T x) by projecting the combined set of data onto the first plane; calculating (310, 502, 602) a second spatial registration that exists between the third two-dimensional medical image and the fourth two-dimensional medical image in the first plane; generating (312, 516, 602) a second correction vector based on the second spatial registration; modifying (314, 518, 602) the combined set of data by applying the second correction vector to one or more of the datum in the combined set of data; and generating (316, 518, 624) a second combined set of data representing a second processed three-dimensional medical image by combining the third set of data and the modified combined set of data.