Three-dimensional (3-D) computed tomography is a widely used technology that visualizes an object’s external and internal structure by assembling a series of two-dimensional images taken sequentially across or around it. However, as anyone who has had a medical magnetic resonance imaging scan will recall, this type of 3-D reconstruction requires the subject to be motionless throughout the capture process, which can take minutes. Capturing a 3-D structure that changes or deforms over time is much more difficult, and existing approaches often yield reconstructions marred by image artifacts and partial surfaces.