Technological advances in computer image analysis have made possible three-dimensional (3D) surface reformations of anatomic structures from contiguous axial CT slices. We have recently utilized this new imaging technique in six patients with primary, isolated craniosynostosis. In each case 3D CT demonstrated the exact extent of synostosis, and in five cases 3D CT images facilitated surgical planning by precisely localizing the proper site for craniectomy. Three-dimensional CT may be a useful adjunct to imaging and surgical planning in this condition.